JPH11112206A - Dielectric filter and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To provide a dielectric filter capable of absorbing a printing shift, a stacking shift, a cut shift and the like in a manufacturing process and improving a yield, and a method of manufacturing the same. An internal ground electrode is provided on a dielectric layer, a capacitor forming internal electrode and an internal ground electrode surrounding the internal electrode are provided on a dielectric layer, and a resonance electrode is provided on the dielectric layer. And an internal ground electrode 230 surrounding the dielectric layer 10
13, a resonance electrode 110 and an internal ground electrode 220 surrounding it are provided on the dielectric layer 1012, and a capacitance forming internal electrode 82 and the internal ground electrode 21 surrounding it are provided on the dielectric layer 1012.
0, and an internal ground electrode 1 on the dielectric layer 1011.
20 are provided. Internal ground electrodes 210, 220, 2
Printing shifts, stacking shifts, cut shifts, and the like in the manufacturing process can be absorbed by the steps 30 and 240, and the characteristics become constant, thereby improving the yield.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric filter and a method of manufacturing the same, and more particularly, to a laminated strip line filter used in a mobile communication device such as a cellular phone and a method of manufacturing the same.

[0002]

2. Description of the Related Art Hitherto, a laminated strip line filter using a distributed constant circuit as an internal electrode instead of a coaxial resonator has been known in addition to a filter using a dielectric coaxial resonator. The latter have a number of advantages over the former. The former is composed of components such as coaxial resonators and capacitive coupling capacitors, but the latter is formed by laminating dielectric sheets and firing them together, or by laminating dielectric blocks, etc. It is lighter in weight and easier to manufacture. Further, the distributed constant circuit, which is the internal electrode of the laminated strip line filter, can have various configurations as needed, so that it is possible to support the same size and different frequencies.

[0003] For the above reasons, as a substitute for a filter using a dielectric coaxial resonator, a multilayer strip line filter having a variety of internal electrode patterns has been proposed so far.

[0004]

However, when a laminated strip line filter is manufactured, a printing displacement lamination displacement or cut displacement may occur. As a result, in a conventional laminated strip line filter, there is a problem. Filter characteristics cannot be obtained, which adversely affects the yield.

Accordingly, an object of the present invention is to provide a dielectric filter, such as a laminated strip line filter, which can suppress the effects of printing displacement, lamination displacement, cut displacement, and the like in the manufacturing stage and can improve the yield, and a dielectric filter thereof. It is to provide a manufacturing method.

[0006]

In order to solve the above-mentioned problems, the present inventors provide a ground electrode at a position corresponding to the outer edge of the element in advance, and electromagnetically form a boundary surface there. It has been found that stable characteristics can be obtained without depending on printing accuracy, lamination accuracy and the like, and that the yield can be improved.

Such a method of intentionally forming an electromagnetic boundary surface inside the element itself can be applied to a device in which a distributed constant circuit such as a single-plate type resonance electrode is exposed, or a laminated type. The range of application is wide.

The element can be cut in a raw sheet state or a cut after firing, and the cutting method can be performed using a conventional high-precision raw cutting machine or a dicing saw as well as a wire saw or a normal peripheral cutting machine. Therefore, there is no need to invest in new facilities, which greatly contributes to the cost.

For example, on the dielectric layer or the dielectric substrate having the electrode for internal resonance, the width of the dielectric layer is set based on the maximum value of the deviation that can occur in each of the manufacturing processes of printing, lamination, and cutting. Alternatively, if an internal ground electrode is installed on the outer edge of the dielectric substrate, the distance between the internal resonance electrode and the ground electrode and the length of the internal resonance electrode on the same plane are kept constant even when printing, lamination, or cut misalignment occurs. Dripping. As a result, variations in filter characteristics can be reduced, which can help improve yield.

[0010] The present invention is based on this finding,
According to claim 1, a dielectric filter comprising: a dielectric; a first plate-like resonance electrode provided in or on the dielectric; and a first ground electrode, A dielectric or a part of the dielectric is sandwiched between the first resonance electrode and the first ground electrode, and a direction from the first resonance electrode toward the first ground electrode is provided. When the dielectric filter is arranged in such a way that substantially the whole of the first resonance electrode overlaps with the first ground electrode when the dielectric filter is viewed in a plan view, A second plane substantially parallel to the first plane including the resonance electrode and having substantially the same height as the first plane intersects an outer surface of the dielectric; The first internal ground electrode inside the body The first internal ground electrode includes first and second sub internal ground electrodes facing each other, and the first resonance electrode is disposed between the first and second sub internal ground electrodes. One end of the first resonance electrode is connected or opposed to the first sub-internal ground electrode, and the other end of the first resonance electrode is connected or opposed to the second sub-internal ground electrode. A dielectric filter is provided.

According to the second aspect, a second flat plate-like resonance electrode is further provided in the dielectric between the first resonance electrode and the first ground electrode. When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, substantially the entire second resonance electrode overlaps with the first ground electrode. A fourth plane that is disposed and that is substantially parallel to a third plane that includes the plate-shaped second resonance electrode and that is substantially the same height as the third plane is an outer surface of the dielectric. A second internal ground electrode is provided inside the dielectric in the vicinity of a second intersection line intersecting, and the second internal ground electrode includes third and fourth sub internal ground electrodes facing each other, The second resonance electrode is connected to the third electrode. And one end of the second resonance electrode is connected or opposed to the third sub internal ground electrode, and the other end of the resonance electrode is connected to the fourth sub internal ground electrode. The dielectric filter according to claim 1, wherein the dielectric filter is connected to or opposed to the sub internal ground electrode.

[0012] By adopting such a structure as described in claim 1 or 2, the first and second sub-electrodes can be formed in the process of manufacturing the dielectric filter, such as electrode formation displacement such as printing displacement, cut displacement and lamination displacement. Internal ground electrode,
Alternatively, it can be absorbed by the first to fourth sub-internal ground electrodes, and as a result, the distance between one end (open end or short-circuit end) of the resonance electrode and the ground,
The distance between the other end (open end or short-circuited end) of the resonance electrode and the ground, and when the resonance electrode is one-side short-circuit type or both-side short-circuit type, the length of the resonance electrode is determined by forming an electrode such as printing deviation. This makes it possible to keep the difference constant regardless of the deviation, the cut deviation, etc., so that the variation in the filter characteristics can be reduced, and as a result, the yield can be improved.

According to another aspect of the present invention, in the case where the dielectric filter includes the first resonance electrode and the first internal ground electrode, the first filter includes a first resonance electrode and a first internal ground electrode. Is a one-sided short-circuit type resonance electrode, and the short-circuited end of the first resonance electrode is
Is provided in connection with the sub internal ground electrode of
The open end of the resonance electrode is provided so as to face the second sub-internal ground electrode, and the dielectric filter comprises:
When the first and second resonance electrodes and the first and second internal ground electrodes are provided, the first and second resonance electrodes are single-sided short-circuited resonance electrodes; A short-circuit end of the first resonance electrode is provided to be connected to the first sub-internal ground electrode, and an open end of the first resonance electrode is provided to face the second sub-internal ground electrode. A short-circuit end of the second resonance electrode is provided to be connected to the third sub-internal ground electrode, and an open end of the second resonance electrode faces the fourth sub-internal ground electrode. There is provided a dielectric filter provided.

According to the third aspect of the present invention, the dielectric member and the first plate-shaped first member provided on the dielectric member or on the dielectric member.
A dielectric filter comprising: a resonance electrode, a first ground electrode, and an input / output terminal electrode, wherein the dielectric material or a part of the dielectric material includes the first resonance electrode and the first Between the first ground electrode and the first ground electrode.
When the dielectric filter is viewed in a plan view along the direction from the resonance electrode to the first ground electrode, substantially the whole of the first resonance electrode is disposed so as to overlap with the first ground electrode. In the obtained dielectric filter,
A first plane, which is substantially parallel to a first plane including the first plate-shaped resonance electrode and has substantially the same height as the first plane, intersects an outer surface of the dielectric. A first internal ground electrode is provided on the inner side of the dielectric near the intersection of the first and second electrodes, over substantially the entire periphery of the dielectric except for a region where the input / output terminal electrode is provided and the vicinity thereof; A first resonance electrode is disposed so as to be surrounded by the first internal ground electrode; one end of the first resonance electrode is connected to or opposed to the first internal ground electrode; A dielectric filter is provided, wherein the other end of the electrode for use is connected to or opposed to the first internal ground electrode.

According to a fourth aspect of the present invention, a second flat plate-like resonance electrode is further provided in the dielectric between the first resonance electrode and the first ground electrode. When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, substantially the entire second resonance electrode overlaps with the first ground electrode. A fourth plane that is disposed and that is substantially parallel to a third plane that includes the plate-shaped second resonance electrode and that is substantially the same height as the third plane is an outer surface of the dielectric. A second internal ground electrode is provided inside the dielectric in the vicinity of the second intersection line, and substantially all around the dielectric except for the area where the input / output terminal electrode is provided and the vicinity thereof. And the second resonance electrode is One end of the second resonance electrode is connected or opposed to the second internal ground electrode, and the other end of the second resonance electrode is connected to the second internal ground electrode. 4. The dielectric filter according to claim 3, wherein said dielectric filter is connected to or opposed to said internal ground electrode.

According to the structure of the third or fourth aspect of the present invention, electrode formation displacement such as printing displacement, cut displacement, lamination displacement and the like in the process of manufacturing the dielectric filter can be reduced by the first internal ground electrode or the second internal ground electrode. 1st and 2nd
As a result, the distance between one end (open end or short-circuit end) of the resonance electrode and the ground, the other end (open end or short-circuit end) of the resonance electrode and the ground Distance, and when the resonance electrode is one-sided short-circuit type or both-side short-circuited type, the length of the resonance electrode can be constant regardless of electrode formation deviation such as printing deviation, cut deviation, and the like. In addition, the electromagnetic field around the resonance electrode can be made substantially constant regardless of printing deviation, cut deviation, and the like, and variations in filter characteristics can be reduced.
As a result, the yield can be improved.

According to another aspect of the present invention, in the case where the dielectric filter includes the first resonance electrode and the first internal ground electrode, the first filter includes a first resonance electrode and a first internal ground electrode. The resonance electrode is a one-sided short-circuit type resonance electrode, a short-circuited end of the first resonance electrode is provided to be connected to the first internal ground electrode, and an open end of the first resonance electrode is provided. When the dielectric filter is provided so as to face the first internal ground electrode, and the dielectric filter includes the first and second resonance electrodes and the first and second internal ground electrodes, The first and second resonance electrodes are one-side short-circuit type resonance electrodes, and a short-circuited end of the first resonance electrode is provided so as to be connected to the first internal ground electrode. The open end of the resonance electrode is A short-circuit end of the second resonance electrode is provided so as to be connected to the second internal ground electrode, and an open end of the second resonance electrode is connected to the second ground electrode. There is provided a dielectric filter which is provided to face an internal ground electrode.

According to a fifth aspect, when the dielectric filter includes the first resonance electrode, the first resonance electrode is a one-side short-circuit type resonance electrode, and When the body filter includes the first and second resonance electrodes, the first and second resonance electrodes are single-sided short-circuiting resonance electrodes, and the first capacitance forming one end is grounded. When the first internal electrode is provided in the dielectric or on the dielectric, and the dielectric filter includes the first resonance electrode, the first resonance electrode is connected to the first resonance electrode.
When the dielectric filter is viewed in a plan view along the direction toward the ground electrode, the other end of the first capacitor forming internal electrode overlaps the open end of the first resonance electrode, and the dielectric When the body filter includes the first and second resonance electrodes, the dielectric filter is viewed in a plan view along a direction from the first resonance electrode to the first ground electrode. A fifth plane in which the other end side of the first capacitance forming internal electrode overlaps with the open end side of the first or second resonance electrode and includes the first capacitance forming internal electrode. The input / output terminal electrode is provided inside the dielectric near a third intersection line where a sixth plane substantially parallel to and at the same height as the fifth plane intersects the outer surface of the dielectric. The invitation excluding the area provided and its vicinity A third internal ground electrode is provided over substantially the entire circumference of the body, and the first capacitance forming internal electrode is disposed so as to be surrounded by the third internal ground electrode, and the first capacitance forming internal electrode is provided. The dielectric filter according to any one of claims 1 to 4, wherein the one end of the electrode is connected to the third internal ground electrode.

According to the present invention, the first and second resonance electrodes are one-side short-circuit type resonance electrodes, and the short-circuited end of the first resonance electrode is connected to the first internal ground. An open end of the first resonance electrode is provided to face the first internal ground electrode, and a short-circuit end of the second resonance electrode is connected to the second internal ground electrode. A first capacitance forming internal electrode provided in connection with an electrode, an open end of the second resonance electrode is provided to face the second internal ground electrode, and one end is grounded; When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, the other end overlaps with the open end of the first resonance electrode. A first capacitance forming internal electrode is the first resonance electrode; Provided on the opposite side of the dielectric or the dielectric on the first ground electrode for,
A third plane, which is substantially parallel to a fifth plane including the first capacitance forming internal electrode and has substantially the same height as the fifth plane, intersects the outer surface of the dielectric. A third internal ground electrode is provided on the inner side of the dielectric near the intersection line and substantially all around the dielectric except for the area where the input / output terminal electrode is provided and the vicinity thereof, The first internal electrode for forming a capacitance is the third electrode
A second capacitance forming internal electrode, one end of which is connected to the third internal ground electrode and one end of which is grounded. When the dielectric filter is viewed in a plan view along a direction from the first resonance electrode to the first ground electrode, the other end side is the open end side of the second resonance electrode. The overlapping second capacitance forming internal electrode is provided in the dielectric between the second resonance electrode and the first ground electrode, and includes the second capacitance forming internal electrode. An eighth plane substantially parallel to the seventh plane and at substantially the same height as the seventh plane intersects with the outer surface of the dielectric and is provided inside the dielectric near a fourth intersection line. Where the terminal electrode is provided and its vicinity A fourth internal ground electrode is provided over substantially the entire periphery of the removed dielectric, and the second capacitance forming internal electrode is disposed so as to be surrounded by the fourth internal ground electrode. The other end of the capacitance forming internal electrode is connected to the fourth internal ground electrode, and the other end of the capacitance forming internal electrode is grounded. The first resonance electrode is connected to the first ground electrode. When the dielectric filter is viewed in a plan view along the direction toward, the other capacitance forming internal electrode whose other end overlaps at least one open end of the first and second resonance electrodes is provided. 5. The dielectric filter according to claim 2, wherein the dielectric filter is not provided in the dielectric between the first resonance electrode and the second resonance electrode.

According to the fifth aspect of the present invention, by providing the first capacitance forming internal electrode, a capacitance is formed between the first capacitance forming internal electrode and the first or second resonance electrode, Further, by providing the first and second capacitance forming internal electrodes as in claim 6 above, between the first capacitance forming internal electrode and the first resonance electrode and the second capacitance formation. Since the capacitance is formed between the internal electrode for use and the second resonance electrode, the center frequency of the filter can be easily changed by changing these capacitances.
Filters having various frequency characteristics can be obtained without changing the outer shape of the dielectric filter. As a result, it is possible to provide filters of the same size and different frequencies, standardize the size, and support a new frequency without changing the design in mounting.

According to a fifth aspect of the present invention, a third internal ground electrode is provided so as to surround the first capacitance forming internal electrode. In a sixth aspect, the first and second capacitance forming internal electrodes are respectively provided. Since the third and fourth internal ground electrodes are provided so as to surround, the electromagnetic field around the capacitance forming internal electrode can be made substantially constant irrespective of printing displacement, cut displacement, and the like.
Variations in filter characteristics can be reduced.

When such an internal electrode for forming a capacitor is provided between the electrodes for resonance, the coupling between the electrodes for resonance greatly changes, and spurious noise occurs in the pass band.
Since desired characteristics may not be obtained, it is preferable that the capacitance forming internal electrode is not provided between the resonance electrodes.

According to a seventh aspect of the present invention, when the dielectric is a ceramic dielectric and the dielectric filter includes the dielectric, the first resonance electrode, and the first internal ground electrode, Is the dielectric, the first
The resonance electrode and the first internal ground electrode are formed by simultaneous firing, and the dielectric filter forms the dielectric, the first and second resonance electrodes, and the first and second internal ground electrodes. If provided, the dielectric, the first and second resonance electrodes, and the first and second internal ground electrodes are formed by simultaneous firing, and the dielectric filter is formed of the dielectric, the first and second internal ground electrodes. A resonance electrode, the first internal ground electrode, the first capacitance forming internal electrode, and the third
When the internal ground electrode is provided, the dielectric,
The first resonance electrode, the first internal ground electrode, the first capacitance forming internal electrode, and the third internal ground electrode are formed by simultaneous firing, and the dielectric filter includes the dielectric, First and second resonance electrodes, the first and second internal ground electrodes,
In the case of including the first capacitance forming internal electrode and the third internal ground electrode, the dielectric, the first and second resonance electrodes, the first and second internal ground electrodes, A first capacitor forming internal electrode and the third internal ground electrode are formed by simultaneous firing, and the dielectric filter comprises the dielectric, the first
And a second resonance electrode, the first and second internal ground electrodes, the first and second capacitance forming internal electrodes, and the third and fourth internal ground electrodes. A body, the first and second electrodes for resonance, the first and second internal ground electrodes,
7. The dielectric filter according to claim 1, wherein the first and second capacitance forming internal electrodes and the third and fourth internal ground electrodes are formed by simultaneous firing. Is provided.

According to claim 8, the dielectric filter further includes an external ground electrode provided on the outer surface of the dielectric, and the dielectric filter includes the first internal ground electrode. When the first internal ground electrode is connected to the external ground electrode at or near the first intersection line, and the dielectric filter includes the first and second internal ground electrodes, First and second internal ground electrodes are connected to the external ground electrode at or near the first and second intersections, respectively, and the dielectric filter includes the first and third internal ground electrodes. In the case, the first and third internal ground electrodes are connected to the external ground electrode by the first and third intersection lines or their intersections. When the dielectric filter includes the first to third internal ground electrodes, the first to third internal ground electrodes are connected to the external ground electrode, respectively. In the case where the dielectric filter includes the first to fourth internal ground electrodes, the first to fourth internal ground electrodes are connected to or near the intersection lines, respectively, and the first to fourth internal ground electrodes are connected to the external ground electrode. 8. The dielectric filter according to claim 1, wherein the dielectric filters are connected at or near the first to fourth intersection lines.

According to a ninth aspect, when the dielectric filter further includes a second ground electrode, and when the dielectric filter includes the first resonance electrode, the first resonance electrode is provided. An electrode is provided in the dielectric so as to be sandwiched between the first and second ground electrodes, and the dielectric filter is arranged in a plan view along a direction from the first resonance electrode toward the first ground electrode. In the case where the first resonance electrode is substantially entirely overlapped with the first and second ground electrodes, and the dielectric filter includes the first and second resonance electrodes, ,
The first and second resonance electrodes are connected to the first and second electrodes.
Provided in the dielectric body between the ground electrodes,
When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, substantially all of the first and second resonance electrodes are the first and second resonance electrodes. When the dielectric filter includes the first resonance electrode and the first capacitance forming internal electrode, the first resonance electrode and the first resonance electrode are arranged so as to overlap the second ground electrode. Is provided in the dielectric so as to be sandwiched between the first and second ground electrodes, and the dielectric is formed along a direction from the first resonance electrode toward the first ground electrode. When the filter is viewed in a plan view, substantially the whole of the first resonance electrode is disposed so as to overlap the first and second ground electrodes, and the dielectric filter is provided with the first and second resonance electrodes. What And when the first capacitance forming internal electrode is provided, the first and second resonance electrodes and the first capacitance forming internal electrode are sandwiched between the first and second ground electrodes. When the dielectric filter is provided in the dielectric and viewed in a plan view of the dielectric filter along a direction from the first resonance electrode to the first ground electrode, the first and second resonance electrodes When substantially the whole is arranged so as to overlap with the first and second ground electrodes, and the dielectric filter includes the first and second resonance electrodes and the first and second capacitance forming internal electrodes. Wherein the first and second resonance electrodes and the first and second capacitance forming internal electrodes are provided in the dielectric so as to be sandwiched between the first and second ground electrodes; resonance Wherein the electrode first
When the dielectric filter is viewed in a plan view along the direction toward the ground electrode, substantially all of the first and second resonance electrodes are arranged so as to overlap with the first and second ground electrodes. 2. The method according to claim 1, wherein
9. A dielectric filter according to any one of claims 1 to 8.

According to a tenth aspect of the present invention, a plurality of resonance electrodes and both ends of each of the plurality of resonance electrodes are provided on the first dielectric or on the first raw sheet containing the dielectric material. First and second ground electrodes respectively disposed on the sides, wherein the first ground electrode to which one end of each of the plurality of resonance electrodes is connected or opposed, and each of the plurality of resonance electrodes The second end, the other end of which is connected or opposed
Forming a ground electrode, and then firing the first dielectric, the first green sheet, a laminate of the first green sheet and another green sheet, and firing the first green sheet A fired body or a fired laminate obtained by firing the laminate,
Cutting along the first and second ground electrodes. A method for manufacturing a dielectric filter is provided.

According to the eleventh aspect, the plurality of resonance electrodes and each of the plurality of resonance electrodes are placed on the first dielectric or on the first raw sheet containing the dielectric material. Except for the area where the output terminal electrode is provided and its vicinity,
Forming a third ground electrode substantially surrounding each of the first and second dielectric sheets, the first dielectric sheet, the first green sheet, a laminate of the first green sheet and another green sheet, Cutting the fired body obtained by firing the first green sheet or the fired laminate obtained by firing the laminate along the third ground electrode. Provided.

According to the manufacturing method of the tenth or eleventh aspect, it is possible to reduce the displacement of the electrode such as the printing displacement, the cut displacement, the lamination displacement, etc. in the process of manufacturing the dielectric filter.
It becomes possible to absorb by the first and second internal ground electrodes or the third internal ground electrode. As a result, the distance between one end (open end or short-circuit end) of the resonance electrode and the ground, the resonance The distance between the other end (open end or short-circuit end) of the electrode and the ground, and when the resonance electrode is a one-sided short-circuit type or a two-sided short-circuit type, the length of the resonance electrode is determined by an electrode formation deviation such as printing deviation, This makes it possible to maintain a constant value regardless of the cut deviation and the like, so that variations in filter characteristics can be reduced, and as a result, the yield can be improved.

According to the twelfth aspect, a plurality of resonance electrodes and both ends of each of the plurality of resonance electrodes are provided on the first dielectric or on the first raw sheet containing the dielectric material. First and second ground electrodes respectively disposed on the sides, wherein the first ground electrode to which one end of each of the plurality of resonance electrodes is connected or opposed, and each of the plurality of resonance electrodes The second end, the other end of which is connected or opposed
A plurality of resonance electrodes and each of the plurality of resonance electrodes are input / output on a first dielectric or on a first raw sheet containing a dielectric material. Forming a third ground electrode substantially surrounding the region except for the region where the terminal electrode is provided and the vicinity thereof, and forming the third ground electrode on the second dielectric or the second raw sheet containing the dielectric material. A plurality of capacitance forming internal electrodes, and a fourth ground electrode substantially surrounding each of the plurality of capacitance forming internal electrodes except for a region where an input / output terminal electrode is provided and its vicinity. Forming a fourth ground electrode to which one end of each of the plurality of capacitance forming internal electrodes is connected, and then laminating the first dielectric and the second dielectric. Or Said the serial first raw sheet second
The first sheet is stacked along a direction from each of the plurality of resonance electrodes to each of the plurality of capacitance forming internal electrodes respectively corresponding to each of the plurality of resonance electrodes. When a first laminated body in which a dielectric and the second dielectric are laminated, or a second laminated body in which the first raw sheet and the second raw sheet are laminated, the plurality of resonances are generated. A step in which each open end of each of the plurality of electrodes overlaps with the other end of each of the plurality of capacitance forming internal electrodes respectively corresponding to each of the plurality of resonance electrodes, and thereafter, the first dielectric And a second dielectric, or a dielectric laminate in which the first dielectric, the second dielectric and another dielectric are laminated, the first raw sheet and the second green Laminating sheets or the first raw sheet and the second raw sheet And a raw sheet laminate obtained by laminating the green sheet with another raw sheet, or a fired laminate obtained by firing the raw sheet laminate, is cut along the first, second, and fourth ground electrodes, or 4) cutting along the ground electrode.

As described above, by providing the capacitance forming internal electrode, the center frequency of the filter can be easily changed, and filters having various frequency characteristics can be obtained without changing the outer shape of the dielectric filter. Since the fourth internal ground electrode is provided so as to surround the capacitance forming internal electrode, the electromagnetic field around the capacitance forming internal electrode can be made substantially constant irrespective of printing displacement, cut displacement and the like. As a result, variations in filter characteristics can be reduced.

According to another aspect of the present invention, the plurality of resonance electrodes are one-side short-circuit type resonance electrodes, and each of the plurality of resonance electrodes has a short-circuited end. Is connected to the first ground electrode, each open end of the plurality of resonance electrodes faces the second ground electrode, or each short-circuit end of the plurality of resonance electrodes is connected to the third ground electrode. A dielectric filter connected to a first region of a ground electrode, wherein an open end of each of the plurality of resonance electrodes is disposed to face a second region of the second ground electrode. Is provided.

[0032]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view for explaining one embodiment of the present invention and a laminated strip line filter for comparison, and FIG. 2 is a laminated strip line of one embodiment of the present invention. FIG. 3 is an exploded perspective view for explaining the filter, and FIG. 3 is a plan view for explaining a screen plate making pattern of a resonance electrode and an input / output extraction electrode of the laminated strip line filter according to one embodiment of the present invention. FIG. 4 is a plan view for explaining a screen plate-making pattern of an internal electrode for forming a capacitance of a laminated strip line filter according to an embodiment of the present invention, and FIG.
FIG. 6 is a plan view for explaining a screen plate making pattern of an internal ground electrode of an embodiment of the present invention and a laminated strip line filter for comparison, FIG.
FIG. 7 is an exploded perspective view illustrating a laminated strip line filter for comparison, and FIG. 7 is a diagram illustrating a screen plate pattern of a resonance electrode and an input / output extraction electrode of the laminated strip line filter for comparison. FIG. 8 is a plan view for explaining a screen plate making pattern of a capacity forming internal electrode of a laminated strip line filter for comparison, and FIG. 9 is an embodiment of the present invention. FIG. 10 is a cross-sectional view for explaining an arrangement relationship among a resonance electrode, an input / output extraction electrode, a capacitance forming internal electrode, and an internal ground electrode of the multilayer strip line filter of FIG. FIG. 11 is a cross-sectional view for explaining an arrangement relationship among a resonance electrode, an input / output extraction electrode, and a capacitance forming internal electrode of the line filter. Is a diagram showing the filter characteristic of the multilayer stripline filter for comparison with the filter characteristic of the multilayer stripline filter according to an embodiment of the invention.

Referring to FIGS. 1 and 2, a laminated strip line filter 100 according to the present embodiment
And input / output terminal electrodes 30 and 40 provided outside thereof
And the external ground terminal electrodes 50 and 60 and the dielectric 1
0, internal ground electrodes 120 and 17 provided inside
0, resonance electrodes 110 and 130, input / output extraction electrodes 115 and 135, capacitance forming internal electrodes 82 and 84,
Internal ground electrodes 210, 220, 230 and 240 are provided. The laminated strip line filter 100 is for surface mounting.

The dielectric 10 has a substantially rectangular parallelepiped shape.
1, a bottom surface 12, opposing side surfaces 13 and 14, and opposing side surfaces 15 and 16.
The width of the dielectric 10, that is, the distance between the side surfaces 15 and 16 is W10.

The external ground electrode 50 includes an external ground side surface electrode 51 and external ground folded electrodes 52 to 5.
And 5. External ground side electrode 51
Is provided on almost the entire side surface 13, the external ground return electrode 52 is provided on the upper surface 11 and near the side surface 13, and the external ground return electrode 53 is provided on the bottom surface 12 and near the side surface 13. The folded back 54 is provided on the side surface 15 and near the side surface 13,
The external ground turn-up 55 is provided on the side surface 16 and near the side surface 13.

The external ground electrode 60 includes an external ground side surface electrode 61 and external ground folded electrodes 62 to 6.
And 5. External ground side electrode 61
Is provided on substantially the entire side surface 14, the external ground return electrode 62 is provided on the upper surface 11 and near the side surface 14, and the external ground return electrode 63 is provided on the bottom surface 12 and near the side surface 14. The folded electrode 64 is provided on the side surface 15 and near the side surface 14, and the external ground folded electrode 65 is provided on the side surface 16 and near the side surface 14.

The input / output electrode 30 comprises an input / output folded terminal electrode 31, an input / output side terminal electrode 32, and an input / output folded terminal electrode 33. The input / output side terminal electrode 32 includes an external ground folded electrode 54,
64, on the center of the side surface 15, the side surface 1
5 over the entire height. The input / output folded terminal electrode 31 is provided on the upper surface 11 and near the side surface 15 in a state of being separated from the external ground folded electrodes 52 and 62, and has a left end on the input / output side terminal electrode 32.
Connected to the upper end of Input / output folded terminal electrode 33
Is provided on the bottom surface 12 and near the side surface 15 in a state of being separated from the external ground folded electrodes 53 and 63,
The left end is connected to the lower end of the input / output side terminal electrode 32.

The input / output electrode 40 includes an input / output folded terminal electrode 41, an input / output side terminal electrode 42, and an input / output folded terminal electrode 43. The input / output side terminal electrode 42 includes an external ground folded electrode 55,
65 at a distance from the center of the side 16,
6 are provided over the entire height. The input / output folded terminal electrode 41 is provided on the upper surface 11 and in the vicinity of the side surface 16 so as to be separated from the external ground folded electrodes 52 and 62, and the right end thereof is provided at the input / output side terminal electrode 42.
Connected to the upper end of Folded terminal electrode 43 for input / output
Is provided on the bottom surface 12 and near the side surface 16 in a state of being separated from the external ground folded electrodes 53 and 63,
The right end is connected to the lower end of the input / output side terminal electrode 42.

The electrode pattern formed on the upper surface 11 and the electrode pattern formed on the bottom surface 12 are the same.

Next, the laminated strip line filter 1
The internal structure of 00 will be described by disassembling the laminated strip line filter 100 into seven filter components 2001 to 2007.

Referring to FIG. 2, the laminated strip line filter 100 includes seven filter components 2001 to 2001.
2007. Filter component 200
1 to 2007 are provided with dielectric layers 1010 to 1016, respectively.

The lower surface of the dielectric layer 1016 is the bottom surface 12 of the dielectric 10, and the input / output folded terminal electrodes 33, 43
In addition, external ground return electrodes 53 and 63 are provided.

On the upper surface of the dielectric layer 1016, an internal ground electrode 170 is provided on almost the entire surface except for the input / output side terminal electrode 32 and its vicinity and the input / output side terminal electrode 42 and its vicinity. I have. The internal ground electrode 170 is connected to the external ground side electrode 51 at the side surface 13, connected to the external ground side electrode 61 at the side surface 14, connected to the external ground turnover electrodes 54 and 64 at the side surface 15, and connected to the external ground turnover at the side surface 16. The electrodes 55 and 65 are connected.

On the upper surface of the dielectric layer 1015, an internal electrode 84 for capacitance formation and an internal ground electrode 240 are provided.

The internal ground electrode 240 extends over substantially the entire periphery of the dielectric 10 except for the input / output side terminal electrode 32 and its vicinity and the input / output side terminal electrode 42 and its vicinity, and Section. The capacitance forming internal electrode 84 is surrounded by the internal ground electrode 240. The internal ground electrodes 240 are sub internal ground electrodes 242, 244, 2
46 and 248. The sub internal ground electrode 242 is connected on the side surface 14 to the external ground side surface electrode 61, and the sub internal ground electrode 244 is connected on the side surface 13 to the external ground side surface electrode 51. The sub internal ground electrode 246 is connected to the external ground folded electrodes 54 and 64 on the side surface 15,
The sub internal ground electrode 248 is connected to the external ground folded electrodes 55 and 65 on the side surface 16.
The sub internal ground electrode 246 is not provided on the input / output side terminal electrode 32 and its vicinity, and the sub internal ground electrode 248 is not provided on the input / output side terminal electrode 42 and its vicinity.

One end of the capacitance forming internal electrode 84 on the side surface 13 side is connected to the sub internal ground side electrode 244 and is provided to extend inward by a predetermined distance therefrom. It has become. Further, in the width direction, they are provided separately from the sub internal ground electrodes 246 and 248, respectively.

On the upper surface of the dielectric layer 1014, a resonance electrode 130, an input / output extraction electrode 135, and an internal ground electrode 230 are provided.

The internal ground electrode 230 extends over substantially the entire periphery of the dielectric 10 except for the input / output side terminal electrode 32 and its vicinity and the input / output side terminal electrode 42, the input / output extraction electrode 135, and the vicinity thereof. It is provided on the edge of the upper surface of the body layer 1014. Resonance electrode 1
Reference numeral 30 is surrounded by an internal ground electrode 230. The internal ground electrode 230 includes sub internal ground electrodes 232, 234, 236 and 238. The sub internal ground electrode 232 is connected to the external ground side electrode 61 on the side surface 14, and the sub internal ground electrode 234 is connected to the external ground side electrode 51 on the side surface 13. Sub internal ground electrode 23
6 is an external ground folded electrode 5 on the side surface 15.
4 and 64, and the sub internal ground electrode 238 is
On the side surface 16, the external ground folded electrodes 55, 6
5 is connected. The sub internal ground electrode 23
6 is not provided on the input / output side terminal electrode 32 and its vicinity, and the sub internal ground electrode 238 is not provided on the input / output side terminal electrode 42, the input / output extraction electrode 135 and their vicinity.

The resonance electrode 130 includes a short-circuit-end resonance electrode 132 on the far side and an open-end resonance electrode 134 on the front side. The short-circuit-side resonance electrode 132 and the open-end resonance electrode 134 are each substantially rectangular in plan view. End 136 on the back side of the short-circuit end side resonance electrode 132
Are connected to the sub internal ground electrode 232. An end 138 on the near side of the open-end resonance electrode 134 is separated from the sub internal ground electrode 234 by a predetermined distance, and is an open end. One end of the input / output extraction electrode 135 is directly connected to the resonance electrode 130, and the other end of the input / output extraction electrode 135 is directly connected to the input / output side terminal electrode 42 on the side surface 16. The length of the short-circuit end side resonance electrode 132 is L31, and the width is W31. The length of the open-end resonance electrode 134 is L32, and the width is W32.

On the upper surface of the dielectric layer 1013, a resonance electrode 110, an input / output extraction electrode 115, and an internal ground electrode 220 are provided.

The internal ground electrode 220 extends over substantially the entire periphery of the dielectric 10 except for the input / output side terminal electrode 32, the input / output extraction electrode 115 and the vicinity thereof, and the input / output side terminal electrode 42 and the vicinity thereof. It is provided on the edge of the upper surface of the body layer 1013. Resonance electrode 1
10 is surrounded by an internal ground electrode 220. The internal ground electrode 220 includes sub internal ground electrodes 222, 224, 226 and 228. The sub internal ground electrode 222 is connected at the side surface 14 to the external ground side surface electrode 61, and the sub internal ground electrode 224 is connected at the side surface 13 to the external ground side surface electrode 51. Sub internal ground electrode 22
6 is an external ground folded electrode 5 on the side surface 15.
4 and 64, and the sub internal ground electrode 228 is
On the side surface 16, the external ground folded electrodes 55, 6
5 is connected. The sub internal ground electrode 22
6 is an input / output side terminal electrode 32, an input / output extraction electrode 115
The sub internal ground electrode 228 is not provided near the input / output side terminal electrode 42 and the vicinity thereof.

The resonance electrode 110 includes a short-circuit-end resonance electrode 112 on the back side and an open-end resonance electrode 114 on the front side. The short-end resonance electrode 112 and the open-end resonance electrode 114 are substantially rectangular in plan view. The rear end 116 of the short-circuit end side resonance electrode 112 is connected to the sub internal ground electrode 222. The front end 118 of the open-end resonance electrode 114 is separated from the internal ground electrode 224 by a predetermined distance, and is an open end. The input / output extraction electrode 11
5 is directly connected, and the other end of the input / output extraction electrode 115 is directly connected to the input / output side terminal electrode 32 on the side surface 15. The length of the short-circuit end side resonance electrode 132 is L1
1, and the width is W11. Open end side resonance electrode 13
4 has a length of L12 and a width of W12.

On the upper surface of the dielectric layer 1012, a capacitance forming internal electrode 82 and an internal ground electrode 210 are provided.

The internal ground electrode 210 extends over substantially the entire periphery of the dielectric 10 except for the input / output side terminal electrode 32 and its vicinity and the input / output side terminal electrode 42 and its vicinity. Section. The capacitance forming internal electrode 82 is surrounded by the internal ground electrode 210. The internal ground electrodes 210 are sub internal ground electrodes 212, 214, 2
16 and 218. The sub internal ground electrode 212 is connected on the side surface 14 to the external ground side electrode 61, and the sub internal ground electrode 214 is connected on the side surface 13 to the external ground side electrode 51. The sub internal ground electrode 216 is connected to the external ground folded electrodes 54 and 64 on the side surface 15,
The sub internal ground electrode 218 is connected to the external ground folded electrodes 55 and 65 on the side surface 16.
The sub internal ground electrode 216 is not provided on the input / output side terminal electrode 32 and its vicinity, and the sub internal ground electrode 218 is not provided on the input / output side terminal electrode 42 and its vicinity.

One end of the capacitor forming internal electrode 82 on the side surface 13 side is connected to the sub internal ground side electrode 214 and is provided to extend inward by a predetermined distance therefrom. It has become. Further, in the width direction, they are provided separately from the sub internal ground electrodes 216 and 218, respectively.

On the upper surface of the dielectric layer 1011, an internal ground electrode 120 is provided on almost the entire surface except for the input / output side terminal electrode 32 and its vicinity and the input / output side terminal electrode 42 and its vicinity. I have. The internal ground electrode 120 is connected on the side surface 13 to the external ground side surface electrode 51, is connected on the side surface 14 to the external ground side surface electrode 61, is connected on the side surface 15 to the external ground return electrodes 54 and 64, and is connected on the side surface 16 to the external ground return side electrode. The electrodes 55 and 65 are connected.

The upper surface of the dielectric layer 1010 is the upper surface 11 of the dielectric 10, and the input / output folded terminal electrodes 31, 4
1 and external ground return electrodes 52 and 62 are provided.

There is no electrode on the lower surface of each of the dielectric layers 1010 to 1015.

Next, a laminated strip line filter 200 for comparison will be described with reference to FIG. In the laminated strip line filter 100 according to the embodiment, the internal ground electrodes 210, 220, 230, and 240 are provided on the upper surfaces of the dielectric layers 1011 to 1015, respectively. The filter 200 does not include these internal ground electrodes 210, 220, 230, 240.
00, but otherwise the same.

To manufacture such laminated strip line filters 100 and 200, a rectangular raw sheet made of a dielectric material is used.

In one embodiment of the present invention, a screen printing pattern 5 shown in FIG.
10, the resonance electrode 110 on the raw sheet 510,
130, the input / output extraction electrodes 115 and 135 and the internal ground electrodes 220 and 230 are printed by screen engraving, and the capacity forming internal electrodes 82 and 84 are formed on the raw sheet 320 as in a screen engraving pattern 520 shown in FIG.
The internal ground electrodes 210 and 240 are printed by screen engraving, and the internal ground electrodes 120 and 170 are printed on the raw sheet 330 by screen engraving like a screen engraving pattern 530 shown in FIG.

The raw sheets on which the electrode patterns are printed are the raw sheets 310 and 32 on which the electrode patterns are printed.
Raw sheets necessary to adjust the thickness of the sheets 0, 330 are appropriately stacked between them, laminated as shown in FIG. After being cut into pieces, they are integrally fired. After firing, the input / output terminal electrodes 30, 4
0, the external ground electrodes 50 and 60 are printed and baked by screen stencil or the like to obtain the laminated strip line filter 100 of the present embodiment.

The screen plate making pattern 51 shown in FIG.
0, the internal ground electrode 22 is located inside the cut reference line 314 on each of four sides of the portion 316 corresponding to one strip line filter.
0 and 230 are provided. Further, in the screen plate making pattern 520 shown in FIG. 4, the internal ground electrodes 210 and 240 are provided inside the cut reference line 324 on each of four sides of the portion 326 corresponding to one strip line filter. . The width of each of the internal ground electrodes 210, 220, 230, and 240 is determined based on the maximum value of a shift that can occur in each of the manufacturing steps of printing, laminating, and cutting. Therefore, the printing shift, the stacking shift and the cut shift are caused by the internal ground electrodes 220 and 230 and the internal ground electrodes 210 and 240.
Can be absorbed.

Therefore, in the laminated strip line filter 100 manufactured as described above, the length of the resonance electrode 110 (the short-circuit end side end 116 and the open end side end 1
18), the length of the resonance electrode 130 (the distance between the short-circuit end 136 and the open end 138), the open end 118 of the resonance electrode 110 and the ground (sub internal ground electrode). 224), the open end 138 of the resonance electrode 130 and the ground (the sub internal ground electrode 2).
34) can be kept constant irrespective of a printing shift, a stacking shift, and a cut shift. Further, the electromagnetic field around the resonance electrodes 110 and 130 can also be changed by the printing shift, the stacking shift,
It is possible to maintain a constant value regardless of the cut gap. Further, the electromagnetic field around the capacitance forming internal electrodes 82 and 84 can be kept constant irrespective of printing displacement, lamination displacement, and cut displacement. As a result, variations in filter characteristics can be reduced, and the yield can be improved.

As described above, the internal ground electrode 220 is formed around the inside of the multilayer strip line filter 100.
By providing the 230 and the internal ground electrodes 210 and 240, a boundary surface can be electromagnetically formed inside the multilayer strip line filter 100,
It is possible to obtain stable characteristics independent of printing accuracy, lamination accuracy, and cut dimensions. Therefore, it is not necessary to adjust the characteristics by trimming or the like after manufacturing the laminated strip line filter 100.

Further, as described above, the width of the internal ground electrodes 210, 220, 230, 240 is determined by printing, laminating,
Since it is determined on the basis of the maximum value of the deviation that can occur in each of the manufacturing processes of the cut, good characteristics can be obtained even when the cut is made to a certain degree at the time of the cut. Therefore, there is no error due to characteristic failure, and almost 100
% Of non-defective products can be obtained. In addition, cutting can be performed with a wire saw or ordinary peripheral blade cutting machine in addition to a high-precision raw cutting machine or dicing saw. .

In order to fabricate a laminated strip line filter 200 for comparison, as shown in FIG.
The resonance electrodes 110 and 130 and the input / output extraction electrodes 115 and 135 are printed on the raw sheet 610 by screen engraving. As shown in FIG. Print and
As shown in FIG. 5, the internal ground electrodes 120 and 170 are printed on the raw sheet 330 by screen engraving. Subsequent steps are the same as those of the laminated strip line filter 100 according to the embodiment of the present invention. In FIGS. 5, 7, and 8, reference numerals 334, 414, and 424 are cut reference lines.

In the laminated strip line filter 200 for this comparison, as in the embodiment of the present invention, the internal ground electrodes 210, 220, 230, 2
When the printing misalignment, the laminating misalignment, and the cut misalignment occur, the length of the resonance electrode 110 (the distance between the short-circuit end 116 and the open end 118) and the length of the resonance electrode 130 are not provided. (The distance between the short-circuit end 136 and the open end 138), the open end 1 of the resonance electrode 110
The distance between the ground electrode 18 and the ground (external ground side electrode 51), the distance between the open end 138 of the resonance electrode 130 and the ground (external ground side electrode 51) are different from the design values. Electrodes 110, 13
The electromagnetic field around 0 also differs from the design value. Further, the electromagnetic field around the capacitance forming internal electrodes 82 and 84 also differs from the design value. As a result, a frequency shift and a variation in filter characteristics occur, which leads to a decrease in yield and an increase in cost. In order to prevent this, for example, it is necessary to concentrate on the nerve near the limit of the cutting accuracy of the dicer. It is necessary to perform an adjustment to make the product acceptable, and to prevent the yield from lowering.

Next, in the manufacturing process of the multilayer strip line filter 200 for comparison with the multilayer strip line filter 100 according to the embodiment of the present invention, the characteristics of each of the filters 100 and 200 in the case where a cut shift occurs will be described. Compare.

As shown in FIGS. 9 and 10, the resonance electrode 1
Let us consider a case where a cut shift of 50 μm occurs on the short-circuit end sides 10 and 130. In the laminated strip line filter 100 according to the embodiment of the present invention, as shown in FIG. 9, the sub internal ground electrode 222 (23
Since 2) is provided in advance, even if a cut deviation of 50 μm occurs on the short-circuit end side of the resonance electrodes 110 and 130, the cut deviation is reduced by the sub internal ground electrode 222.
(232). Therefore, the resonance electrode 1
10 (the short end 116 and the open end 118
) And the length of the resonance electrode 130 (the distance between the short-circuit end 136 and the open end 138), and the electromagnetic force around the resonance electrodes 110 and 130 is not changed. The electromagnetic field around the field and the capacitance forming internal electrodes 82 and 84 does not change. As a result, as shown in FIG. 11, there is almost no shift of the center frequency, and other filter characteristics hardly change. Also, for example, even if a cut deviation of 50 μm occurs on the open ends of the resonance electrodes 110 and 130,
The cut misalignment is caused by the sub internal ground electrode 224 (23
4), the length of the resonance electrode 110 and the length of the resonance electrode 130 do not change, and the electromagnetic fields around the resonance electrodes 110 and 130 and the capacitance forming internal electrodes 82 and 84 The surrounding electromagnetic field does not change. As a result, as shown in FIG. 11, there is almost no shift of the center frequency, and other filter characteristics hardly change. In FIG. 11, the solid line is 50 μm on the short-circuit end side in the laminated strip line filter 200 for comparison.
The broken line indicates the case where there is no cut-off in the laminated strip line filter 200 for comparison, and the dashed line indicates the case where there is a cut-off in the laminated strip line filter 200 of this embodiment.
The graph shows the filter characteristics when there is a cut shift of m.

In the laminated strip line filter 200 for comparison, as shown in FIG.
Occurs on the short-circuit end side of the resonance electrodes 110 and 130, the length of the resonance electrodes 110 and 130 is shortened accordingly. As a result, as shown by the solid line in FIG. 11, the center frequency shifts to a high frequency side of about 50 MHz. Also,
When a cut gap of 50 μm occurs on the open ends of the resonance electrodes 110 and 130, the center frequency is shifted by about 30 to 50 MHz to the lower frequency side, though not shown.

Next, the resonance electrode 1 according to the present embodiment will be described.
10, 130 and their resonance electrodes 110, 130
The relationship between the capacitance-forming internal electrodes 82 and 84 will be described.

In this embodiment, the width W12 of the open-end resonance electrode 114, the width W32 of the open-end resonance electrode 134, the width W11 of the short-end resonance electrode 112, and the short-end resonance electrode 132 Adopts a broad side strip line structure with a wide width W31.
12, W32, W11 and W31 are the width W1 of the dielectric 10
It is preferably 40% to 80% of 0. Alternatively, the wavelength is preferably in the range of λ / 32 to λ / 4 (where λ is a wavelength at the center frequency to be used).

The resonance electrode 1 on the short-circuit end side of the resonance electrode 110
Numeral 12 is shifted to the left in the width direction of the dielectric 10 to the left, and the short-circuit end side resonance electrode 132 of the resonance electrode 130 is shifted to the right in the width direction of the dielectric 10. Are shifted left and right in the width direction (that is, adopt an offset broadside coupled stripline structure).

The open end side resonance electrode 1 of the resonance electrode 110
14 is disposed at the center of the dielectric 10, and the open end side resonance electrode 134 of the resonance electrode 130 is disposed at the center of the dielectric 10, when both are viewed from above the dielectric 10. (That is, a broadside coupled stripline structure is adopted).

As in the present embodiment, the overlapping area between the open-end-side resonance electrode 114 and the open-end-side resonance electrode 134 is reduced by the short-circuit end-side resonance electrode 112 and the short-circuit end-side resonance electrode 1.
By making the area larger than the overlap area of 32, a notch (attenuation pole) is present, and accordingly, the pass bandwidth is narrowed, and excellent characteristics are obtained.

The capacitance forming internal electrode 82 is formed on the dielectric layer 10.
12 overlaps with the open end side resonance electrode 114 of the resonance electrode 110 by a predetermined area, and a capacitance C1 is provided between the capacitance forming internal electrode 82 and the open end side resonance electrode 114. Is formed.

The capacitance forming internal electrode 84 is
4 with the open end side resonance electrode 134 of the resonance electrode 130 having a predetermined area, and a capacitance C2 between the capacitance forming internal electrode 84 and the open end side resonance electrode 134. Is formed.

The resonance electrodes 110 and 130 are formed so as to be line-symmetric with respect to the center line in the width direction of the dielectric 10 in the left and right directions.

In this embodiment, the capacitance forming internal electrode 8
The center of the filter is changed by changing the capacitance C1 formed between the second electrode 2 and the open-end resonance electrode 114 and the capacitance C2 formed between the capacitance-forming internal electrode 84 and the open-end resonance electrode 134. Frequency can be changed easily,
Filters having various frequency characteristics can be obtained without changing the outer shape of the laminated strip line filter 100. As a result, filters of the same size and different frequencies can be provided, and the size can be standardized. as a result,
A new frequency can be handled without any design change in mounting. The capacitance C1 can be easily changed by changing the distance and the amount of overlap between the capacitance forming internal electrode 82 and the open end side resonance electrode 114.
2 is a capacitance forming internal electrode 84 and an open end side resonance electrode 1
It can be easily changed by changing the distance and the amount of overlap between them.

It is preferable that the capacitance forming internal electrodes such as the capacitance forming internal electrodes 82 and 84 are not provided between the resonance electrodes 110 and 130. If the resonance electrode 11
When provided between 0 and 130, the coupling between the resonance electrodes 110 and 130 changes greatly, and desired characteristics such as spurious generation in the pass band cannot be obtained.

In this embodiment, the capacitance forming internal electrode 8
2 and the capacitor C2 formed between the capacitance-forming internal electrode 84 and the open-end resonance electrode 134, the capacitance C1 formed between the open-end resonance electrode 114 and the open-end resonance electrode 114 is different. The width W12 of the side resonance electrode 114, the width W32 of the open end side resonance electrode 134 (W12 = W32), the width W11 of the short end side resonance electrode 112, and the width W31 of the short end end resonance electrode 132 (W11 = W31). ), Open end side offset length, short end end side offset length, open end side resonance electrode length L12, L32 (L12 = L32), short end resonance electrode length L11, L31 (L11 = L31), open end side resonance Can be designed with eight parameters, ie, the electrode stacking direction interval and the short-circuit end side resonance electrode stacking direction interval, making it easier to design the filter characteristics and widening the design range. It becomes flexible to be able to correspond to the specification.

The internal ground electrodes 120, 1
Since 70 is provided inside the dielectric 10 by integral firing, it is protected by the dielectric layers 1010 and 1016, respectively. The adverse effect on the filter characteristics is prevented. Further, since it is formed by integral firing as described above, the internal ground electrode 12
It is easy to form 0 and 170 inside the dielectric 10.

In the above embodiment, the most preferable configuration is provided with the capacitance forming internal electrodes 82 and 84. However, the present invention is applicable to a filter having no such capacitance forming internal electrode. it can. In this case, the center frequency of the filter varies due to the capacitance between the open-end-side resonance electrode 114 and the external ground side electrode 51 and the capacitance between the open-end-side resonance electrode 134 and the external ground side electrode 51. As described in the present invention, by providing the internal ground electrodes 220 and 230, and particularly, by providing the sub internal ground electrodes 224 and 234 provided opposite to the open end portions 118 and 138, as in the present invention, the printing deviation, Even if cut displacement or lamination displacement occurs, the capacitance between the open end side resonance electrode 114 and the external ground side surface electrode 51 and the capacitance between the open end side resonance electrode 134 and the external ground side surface electrode 51 are hardly affected. And the center frequency hardly shifts.

Further, in the above-described embodiment, as a most preferable form, a laminate of the raw sheets on which the electrode patterns are printed is cut. However, according to the present invention, the element is cut in the raw sheet state. It can be cut or cut after firing. Therefore, for example, the raw sheet may be cut first and then laminated, or the laminated raw sheet may be fired and then cut.

Although the laminated strip line filter 100 of the above embodiment is manufactured by integral firing as a more preferable manufacturing method, the present invention can also be applied to a strip line filter having a structure in which dielectric blocks are bonded. Also in this case, the element can be cut before and after lamination.

In the above-described embodiment, the most preferable configuration is a stacked strip line filter structure. However, as described above, the present invention provides an electromagnetic boundary surface formed by the ground electrode inside the device itself. Since it is made intentionally, it can be applied to a single plate type resonance electrode or the like having an exposed distributed constant circuit, and its application range is wide.

In the above-described embodiment, as the most preferable form, the resonance electrodes 110 and 130 have an offset broadside coupled stripline structure at the short-circuited end and a broadside coupled stripline structure at the open end. However, it is also preferable for a stripline filter in which the resonance electrodes 110 and 130 have a structure in which the open ends have an offset broadside coupled stripline structure and the short ends have a broadside coupled stripline structure. The present invention can be applied to a strip line filter in which both the open end side and the short-circuit end side overlap in a plan view, and both the open-end side and the short-circuit end side have a broadside coupled strip line structure. Further, the present invention can be applied to a stripline filter having various types of resonance electrodes other than the broadside stripline structure.

[0090]

According to the present invention, a dielectric filter such as a laminated strip line filter can be manufactured at a high yield and can be provided at low cost. Further, it can contribute to cost reduction of mobile communication equipment using a dielectric filter such as a laminated strip line filter.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an embodiment of the present invention and a laminated strip line filter for comparison.

FIG. 2 is an exploded perspective view illustrating a laminated strip line filter according to an embodiment of the present invention.

FIG. 3 is a plan view for explaining a screen plate making pattern of a resonance electrode and an input / output extraction electrode of the laminated strip line filter according to one embodiment of the present invention.

FIG. 4 is a plan view for explaining a screen plate making pattern of an internal electrode for forming a capacitance of the laminated strip line filter according to one embodiment of the present invention.

FIG. 5 is a plan view for explaining a screen plate making pattern of an internal ground electrode of a laminated strip line filter according to an embodiment of the present invention and a comparative example.

FIG. 6 is an exploded perspective view illustrating a laminated strip line filter for comparison.

FIG. 7 is a plan view for explaining a screen plate making pattern of a resonance electrode and an input / output extraction electrode of a laminated strip line filter for comparison.

FIG. 8 is a plan view for explaining a screen plate making pattern of a capacity forming internal electrode of a laminated strip line filter for comparison.

FIG. 9 is a cross-sectional view for explaining an arrangement relationship among a resonance electrode, an input / output extraction electrode, an internal electrode for forming a capacitor, and an internal ground electrode of the laminated strip line filter according to one embodiment of the present invention.

FIG. 10 is a cross-sectional view for describing an arrangement relationship among a resonance electrode, an input / output extraction electrode, and a capacitance forming internal electrode of a laminated strip line filter for comparison.

FIG. 11 is a diagram showing filter characteristics of the multilayer strip line filter according to the embodiment of the present invention and filter characteristics of the multilayer strip line filter for comparison.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Dielectric 1010-1016 ... Dielectric layer 30, 40 ... Input / output terminal electrode 31, 33, 41, 43 ... Input / output folded terminal electrode 32, 42 ... Input / output side terminal electrode 50, 60 ... External Ground electrodes 52 to 55, 62 to 65: External ground folded electrodes 51, 61: External ground side electrodes 82, 84 ... Internal electrodes for forming capacitance 100, 200 ... Laminated strip line filters 110, 130 ... Resonant electrodes 112, 132 ... Short-circuit end side resonance electrodes 114, 134 ... Open end side resonance electrodes 115, 135 ... I / O extraction electrodes 120, 170 ... Internal ground electrodes 210, 220, 230, 240 ... Internal ground electrodes 212, 214, 216, 218 , 222, 223, 2
24, 228, 232, 234, 236, 238, 24
2, 244, 246, 248 ... sub-internal ground electrodes 310, 320, 330, 410, 420 ... raw sheet 312, 322, 332 ... internal ground electrodes 314, 324, 334, 414, 424 ... cutting reference lines 316, 326 336, 416, 426: One strip line filter area 318, 328: Design outer circumference 510, 520, 530, 610, 620: Screen plate making pattern

Claims (12)

[Claims] 1. A dielectric filter comprising: a dielectric; a first plate-like resonance electrode provided on or on said dielectric; and a first ground electrode, said dielectric filter comprising: Alternatively, a part of the dielectric is sandwiched between the first resonance electrode and the first ground electrode, and extends in a direction from the first resonance electrode to the first ground electrode. In a dielectric filter in which substantially the entire first resonance electrode overlaps with the first ground electrode when the dielectric filter is viewed in a plan view, A second plane substantially parallel to the first plane containing the electrodes and having substantially the same height as the first plane intersects with the outer surface of the dielectric. On the inside, a first internal ground electrode is provided. The first internal ground electrode includes first and second sub internal ground electrodes facing each other, and the first resonance electrode is disposed between the first and second sub internal ground electrodes. And one end of the first resonance electrode is connected or opposed to the first sub-internal ground electrode, and the other end of the first resonance electrode is connected or opposed to the second sub-internal ground electrode. A dielectric filter, characterized in that: 2. A second plate-like resonance electrode is further provided in the dielectric between the first resonance electrode and the first ground electrode, and When the dielectric filter is viewed in a plan view along the direction toward the first ground electrode, substantially the entire second resonance electrode is disposed so as to overlap with the first ground electrode, and In the vicinity of a second intersection line where a fourth plane substantially parallel to the third plane including the second resonance electrode and having substantially the same height as the third plane intersects the outer surface of the dielectric. Wherein a second internal ground electrode is provided inside the dielectric material, and wherein the second internal ground electrode comprises third and fourth sub internal ground electrodes facing each other, and wherein the second resonance electrode is , The third and fourth sub-internal grouts One end of the second resonance electrode is connected to or opposed to the third sub internal ground electrode, and the other end of the resonance electrode is connected to the fourth sub internal ground electrode. 2. The dielectric filter according to claim 1, wherein the dielectric filter faces each other. 3. A dielectric filter comprising: a dielectric; a first plate-shaped resonance electrode provided in or on the dielectric; a first ground electrode; and an input / output terminal electrode. Wherein the dielectric or a part of the dielectric is sandwiched between the first resonance electrode and the first ground electrode, and the first resonance electrode is
When the dielectric filter is viewed in a plan view along the direction toward the ground electrode, substantially the entirety of the first resonance electrode overlaps with the first ground electrode. A first plane substantially parallel to the first plane including the first plate-like resonance electrode and having substantially the same height as the first plane intersects the outer surface of the dielectric. A first internal ground electrode is provided on the inner side of the dielectric near the intersection line, over substantially the entire periphery of the dielectric except for a region where the input / output terminal electrode is provided and the vicinity thereof, One resonance electrode is disposed so as to be surrounded by the first internal ground electrode; one end of the first resonance electrode is connected to or opposed to the first internal ground electrode; The other end of the electrode is in front Dielectric filter characterized in that it is connected or facing the first internal ground electrode. 4. A second plate-like resonance electrode is further provided in the dielectric between the first resonance electrode and the first ground electrode, and the second resonance electrode is formed from the first resonance electrode. When the dielectric filter is viewed in a plan view along the direction toward the first ground electrode, substantially the entirety of the second resonance electrode is disposed so as to overlap with the first ground electrode. Near a second intersection line at which a fourth plane substantially parallel to the third plane including the second resonance electrode and having substantially the same height as the third plane intersects the outer surface of the dielectric. A second internal ground electrode is provided inside substantially the entire periphery of the dielectric except for a region where the input / output terminal electrode is provided and the vicinity thereof, inside the dielectric, Electrode for the second internal ground One end of the second resonance electrode is connected or opposed to the second internal ground electrode, and the other end of the second resonance electrode is connected to the second internal ground electrode. 4. The dielectric filter according to claim 3, wherein the dielectric filter is connected or opposed. 5. When the dielectric filter includes the first resonance electrode, the first resonance electrode is a one-side short-circuit type resonance electrode, and the dielectric filter is the first and second resonance electrodes. When the second resonance electrode is provided, the first and second resonance electrodes are single-sided short-circuiting resonance electrodes, and the first capacitance forming internal electrode, one end of which is grounded, is formed of the dielectric material. Alternatively, when the dielectric filter is provided on the dielectric, and the dielectric filter includes the first resonance electrode, the dielectric filter extends along a direction from the first resonance electrode to the first ground electrode. When the filter is viewed in a plan view, the other end of the first capacitance forming internal electrode overlaps with the open end of the first resonance electrode, and the dielectric filter is connected to the first and second resonance electrodes. The first resonance, From the first electrode
When the dielectric filter is viewed in plan along the direction toward the ground electrode, the other end of the first capacitor forming internal electrode is connected to the open end of the first or second resonance electrode. A sixth plane substantially parallel to the fifth plane including the first capacitance forming internal electrode and having substantially the same height as the fifth plane intersects the outer surface of the dielectric; A third internal ground electrode is provided on the inside of the dielectric near the intersection of 3 and around substantially the entire periphery of the dielectric except for a region where the input / output terminal electrode is provided and the vicinity thereof; The first capacitance forming internal electrode is disposed so as to be surrounded by the third internal ground electrode, and the one end of the first capacitance forming internal electrode is connected to the third internal ground electrode. 2. The method according to claim 1, wherein The dielectric filter according to any one of Itaru 4. 6. The first and second resonance electrodes are one-side short-circuit type resonance electrodes, and a short-circuited end of the first resonance electrode is provided so as to be connected to the first internal ground electrode. An open end of the first resonance electrode is provided to face the first internal ground electrode, and a short-circuit end of the second resonance electrode is provided to be connected to the second internal ground electrode. An open end of the second resonance electrode is provided to face the second internal ground electrode, and a first capacitance forming internal electrode having one end grounded,
When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, the other end overlaps the open end of the first resonance electrode. A first capacitance forming internal electrode provided on the dielectric or on the dielectric opposite to the first ground electrode with respect to the first resonance electrode; The inside of the dielectric near a third intersection line where a sixth plane substantially parallel to the fifth plane and having substantially the same height as the fifth plane intersects the outer surface of the dielectric. A third internal ground electrode is provided over substantially the entire periphery of the dielectric except for a region where the input / output terminal electrode is provided and the vicinity thereof, and the first capacitance forming internal electrode comprises: Surrounded by the third internal ground electrode Is disposed, said one end of the first capacitor forming the internal electrode is connected to the third internal ground electrode, a second capacitor forming the internal electrode one end of which is grounded,
When the dielectric filter is viewed in a plan view along the direction from the first resonance electrode to the first ground electrode, the other end overlaps with the open end of the second resonance electrode. A second capacitor forming internal electrode is provided in the dielectric between the second resonance electrode and the first ground electrode, and a seventh capacitor including the second capacitor forming internal electrode is provided. The input / output terminal is located inside the dielectric near a fourth intersection line where an eighth plane that is substantially parallel to the plane of the above and that is substantially the same height as the seventh plane intersects the outer surface of the dielectric. A fourth internal ground electrode is provided over substantially the entire periphery of the dielectric except for a region where the electrode is provided and the vicinity thereof, and the second capacitor forming internal electrode is provided with the fourth internal ground electrode. Is arranged around the first The other end of the volume forming internal electrode is connected to the fourth internal ground electrode, and the other end is grounded to another capacitance forming internal electrode, the first resonance electrode being connected to the first ground electrode. When the dielectric filter is viewed in a plan view along the direction toward, the other capacitance forming internal electrode whose other end overlaps at least one open end of the first and second resonance electrodes is provided. 5. The dielectric filter according to claim 2, wherein the dielectric filter is not provided in the dielectric between the first resonance electrode and the second resonance electrode. 7. When the dielectric is a ceramic dielectric, and when the dielectric filter includes the dielectric, the first resonance electrode, and the first internal ground electrode, the dielectric filter includes: A first resonance electrode and the first internal ground electrode are formed by simultaneous firing; and the dielectric filter is formed of the dielectric, the first and second electrodes.
The resonance electrode and the first and second internal ground electrodes, the dielectric, the first and second resonance electrodes, and the first and second internal ground electrodes are simultaneously fired. When the dielectric filter includes the dielectric, the first resonance electrode, the first internal ground electrode, the first capacitance forming internal electrode, and the third internal ground electrode, , The dielectric, the first resonance electrode,
The first internal ground electrode, the first capacitance forming internal electrode and the third internal ground electrode are formed by simultaneous firing, and the dielectric filter is formed of the dielectric, the first and the second.
In the case where the device includes the resonance electrode, the first and second internal ground electrodes, the first capacitance forming internal electrode, and the third internal ground electrode, the dielectric, the first and second internal ground electrodes, The resonance electrode, the first and second internal ground electrodes, the first capacitance forming internal electrode and the third internal ground electrode are formed by simultaneous firing, and the dielectric filter includes the dielectric, the dielectric, In the case of including first and second resonance electrodes, the first and second internal ground electrodes, the first and second capacitance forming internal electrodes, and the third and fourth internal ground electrodes, The dielectric, the first and second resonance electrodes, the first and second internal ground electrodes, the first and second capacitance forming internal electrodes, and the third and second electrodes. 7. The dielectric filter according to claim 1, wherein said internal ground electrode is formed by simultaneous firing. 8. The first filter according to claim 1, wherein said dielectric filter further comprises an external ground electrode provided on said outer surface of said dielectric, and wherein said dielectric filter comprises said first internal ground electrode. When a ground electrode is connected to the external ground electrode at or near the first intersection line, and the dielectric filter includes the first and second internal ground electrodes, the first and second internal When a ground electrode is connected to the external ground electrode at or near the first and second intersection lines, respectively, and the dielectric filter includes the first and third internal ground electrodes, the first And a third internal ground electrode connected to the external ground electrode at or near the first and third intersections, respectively. When the dielectric filter includes the first to third internal ground electrodes, the first to third internal ground electrodes are connected to the external ground electrode at the first to third intersections or in the vicinity thereof. When the dielectric filter includes the first to fourth internal ground electrodes, the first to fourth internal ground electrodes are connected to the external ground electrode by the first to fourth interchanges. The dielectric filter according to any one of claims 1 to 7, wherein the dielectric filter is connected at or near a line. 9. When the dielectric filter further includes a second ground electrode, and when the dielectric filter includes the first resonance electrode, the first resonance electrode includes the first and second resonance electrodes. The first filter is provided between the first ground electrode and the first resonance electrode in a direction from the first resonance electrode to the first ground electrode. When the dielectric filter is provided with the first and second resonance electrodes, substantially the entirety of the resonance electrode is disposed so as to overlap the first and second ground electrodes. Is provided in the dielectric so as to be sandwiched between the first and second ground electrodes.
When the dielectric filter is viewed in a plan view along the direction toward the ground electrode, substantially the entirety of the first and second resonance electrodes are arranged so as to overlap with the first and second ground electrodes, In the case where the dielectric filter includes the first resonance electrode and the first capacitance forming internal electrode, the first
And the first capacitance forming internal electrode are provided in the dielectric so as to be sandwiched between the first and second ground electrodes, and the first resonance electrode is connected to the first ground electrode. When the dielectric filter is viewed in a plan view along a direction toward the first electrode, substantially the entire first resonance electrode is disposed so as to overlap the first and second ground electrodes. When the first and second resonance electrodes and the first capacitance forming internal electrode are provided, the first and second resonance electrodes and the first
Is provided in the dielectric so as to be sandwiched between the first and second ground electrodes, and the dielectric is formed along a direction from the first resonance electrode toward the first ground electrode. When the filter is viewed in a plan view, substantially all of the first and second resonance electrodes are arranged so as to overlap the first and second ground electrodes, and the dielectric filter is provided in the first and second resonance electrodes. When a resonance electrode and the first and second capacitance-forming internal electrodes are provided, the first and second resonance electrodes and the first and second capacitance-forming internal electrodes are the first and second capacitance-forming internal electrodes.
And provided in the dielectric material between the second ground electrode and the dielectric filter when viewed in a plan view along the direction from the first resonance electrode to the first ground electrode. 9. The dielectric filter according to claim 1, wherein substantially all of the first and second resonance electrodes are arranged so as to overlap with the first and second ground electrodes. 10. A plurality of resonance electrodes and a plurality of resonance electrodes disposed on both ends of each of the plurality of resonance electrodes on a first dielectric or on a first raw sheet containing a dielectric material. 1
And a second ground electrode, wherein one end of each of the plurality of resonance electrodes is connected or opposed to the first ground electrode, and the other end of each of the plurality of resonance electrodes is connected or opposed to each other. Forming a second ground electrode; and thereafter, the first dielectric, the first raw sheet, a laminate of the first raw sheet and another raw sheet, the first raw sheet Cutting a fired body obtained by firing the above or a fired laminated body obtained by firing the laminate along the first and second ground electrodes. 11. A plurality of resonance electrodes and an input / output terminal electrode for each of the plurality of resonance electrodes are provided on a first dielectric or on a first raw sheet containing a dielectric material. Forming a third ground electrode substantially surrounding each other except for the region and the vicinity thereof; and thereafter, forming the first dielectric, the first raw sheet, the first raw sheet and other Cutting a laminate with a raw sheet, a fired body obtained by firing the first raw sheet, or a fired laminate obtained by firing the laminate along the third ground electrode. Of manufacturing a dielectric filter. 12. A plurality of resonance electrodes and a plurality of resonance electrodes disposed on both ends of each of the plurality of resonance electrodes on a first dielectric or on a first raw sheet containing a dielectric material. 1
And a second ground electrode, wherein one end of each of the plurality of resonance electrodes is connected or opposed to the first ground electrode, and the other end of each of the plurality of resonance electrodes is connected or opposed to each other. Forming a second ground electrode, or on a first dielectric or on a first raw sheet containing a dielectric material, a plurality of resonance electrodes and each of the plurality of resonance electrodes, Forming a third ground electrode substantially surrounding the region except for the region where the input / output terminal electrode is provided and the vicinity thereof; and a second raw sheet including a second dielectric material or a dielectric material. A plurality of capacitance forming internal electrodes, and a fourth ground electrode substantially surrounding each of the plurality of capacitance forming internal electrodes except for a region where input / output terminal electrodes are provided and the vicinity thereof, There, the fourth one end of each of the plurality of capacitance forming internal electrodes are connected
Forming a ground electrode, and then laminating the first dielectric and the second dielectric, or laminating the first raw sheet and the second raw sheet, The first dielectric and the second dielectric along a direction from each of the plurality of resonance electrodes toward each of the plurality of capacitance forming internal electrodes respectively corresponding to each of the plurality of resonance electrodes; When a first laminate obtained by laminating the first and second laminates obtained by laminating the first raw sheet and the second raw sheet is viewed, the open end of each of the plurality of resonance electrodes is A step of overlapping the other end of each of the plurality of capacitance forming internal electrodes respectively corresponding to each of the plurality of resonance electrodes; and thereafter, the first dielectric and the second dielectric are Lamination or the first dielectric and the second dielectric And a dielectric laminate in which the first raw sheet and the second raw sheet are laminated, or the first raw sheet, the second raw sheet, and another raw sheet are laminated. Or a fired laminate obtained by firing the raw sheet laminate is cut along the first, second, and fourth ground electrodes, or cut along the third and fourth ground electrodes. And cutting the substrate by a method of producing a dielectric filter.