JPS59997A - Method of producing ceramic substrate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Object of the Invention The present invention relates to a ceramic substrate manufacturing method that is optimal when manufacturing a multilayer ceramic substrate using a sheet lamination method, and particularly improves the accuracy of positioning work in the manufacturing process. The present invention relates to a ceramic substrate manufacturing method.

As a conventional method for manufacturing a multilayer ceramic substrate, there is a so-called sheet lamination method in which a large number of green sheets are laminated and bonded together by drilling holes in the green sheets, filling the holes with conductors, and printing wiring patterns. In order to manufacture a substrate with an ultra-high density wiring pattern using this method, the key point is to accurately perform various positionings in the manufacturing process.

Conventionally, this positioning has been performed by abutting the end surface of the green sheet against a positioning block, or by inserting a guide hole punched in the green sheet into a guide bin of a positioning table for each process. FIG. 1 shows a method for manufacturing a multilayer ceramic substrate using the latter positioning method.

First, guide holes 2 are punched in a green sheet 1 as shown in FIG. 1(a). Next, as shown in FIG. 1(b), the guide holes 2 of the sheet 1 are inserted into the guide bins 4 of the lower mold 3 of the pier hole punching die for positioning, and pier holes 5 are punched at predetermined positions of the sheet 1. *In addition to punching with a mold, the pier hole can be formed using a well-known method of drilling a hole in a predetermined position using an NC drilling machine, and the positioning method is the same as in this example.

Next, the above-mentioned peer hole is filled with conductive paste. The conductive paste used is a paste obtained by adding an organic binder and a solvent to Mo or W powder. Filling with the conductive paste is performed using a well-known method such as screen printing or vacuum suction.

To explain the screen printing method as an example, Figure 1 (C
), insert the guide hole 2 of the sheet 1 into the guide bin 7 of the positioning table 6 of the conductor filling device, position it, and match the position of the pier hole to be filled with conductor paste into the opening of the screen (not shown). The conductive paste 8 was filled with the conductive paste 8.

Next, as shown in FIG. 1(d), a wiring pattern 9 is printed using the screen printing method as in the case of filling the conductor.

Next, as shown in FIG. 1(6), a predetermined number of sheets with wiring patterns printed thereon are laminated and then heated and pressed to bond and integrate them. At this time, in order to position each sheet,
This is done by inserting the guide hole 2 of the sheet 1 into the guide bin 11 of the lamination jig 10.

Next, as shown in FIG. 1(f), the guide hole 13 of the sheet 12 integrated by adhesive is inserted into the guide bin 16 of the lower leg 15 of the product punching die, and the product part 1 whose outer shape is indicated by the dotted line 17
Punch out 8. Thereafter, sintering is performed using a well-known method, and the front and back conductors are plated with Ni, Au, etc., to complete the board.

As described above with reference to FIG. 1, in the conventional manufacturing method, guide holes punched in a green sheet are inserted into guide bins of a positioning table in each process to perform positioning. However, as is well known, green sheets are made by supplying ceramic raw material powder such as alumina with an organic binder and forming it into a sheet shape, so it is easily deformed during the process, and the guide holes are not connected to the guide bins. By repeating insertion and removal, the guide hole also loses its shape.

For this reason, the positioning accuracy is limited to approximately ±0.1, and this poor positioning accuracy has been an obstacle in manufacturing large multilayer substrates with ultra-high density. For example, in a pier-hole conductor filling process using a screen printing method, if a misalignment occurs between the opening of the screen and the pier-hole position of the sheet, the conductor paste will not be completely filled. That is, as shown in FIG. 2, when the guide hole 2 of the sheet 1 is deformed 19 and the sheet 1 is set with a positional deviation with respect to the positioning table 3 of the hole filling device, the screen 20 A positional shift occurs between the opening 21 of the sheet 1 and the pier hole 5 of the sheet 1. If the conductive paste 8 is discharged into the pier holes 5 of the sheet 1 through the opening 21 of the screen 20 by moving the squeegee 22 in this state, a sufficient discharge amount will not be obtained and the conductive paste will stop midway through the pier holes. It is clear that such an incompletely filled conductor paste 23 causes an open failure of the substrate after lamination bonding and sintering.

Next, FIG. 3 shows an example of a case where a problem occurs due to positional deviation between sheets in the lamination bonding process.

In other words, due to the misalignment between the seat 1 and the seat 1-IA, conductivity cannot be established between the pier hole 24 of the seat 1 and the pier hole 24A of the seat IA, resulting in an open defect (defective location 25). . Also, due to the misalignment between sheet IA and sheet IB, the pier hole 2 of sheet IB
4B Between the wiring line 26A of the sheet IA and
A defect (defect location 27) has occurred.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a ceramic substrate manufacturing method that can manufacture the positions of green sheets in the steps of filling conductors in peer holes, wiring batten printing, and laminating bonding processes of multilayer ceramic substrates using a lamination method.

In the ceramic substrate manufacturing method of the present invention, images of reference marks provided at at least two locations on a sheet mounted on a table at a positioning position are projected on a monitor television;
After finely adjusting the table so that it is in the specified position of the TV, it is fixed, and then the table is moved to the working position to perform various tasks such as filling conductors into the seat pier holes, printing wiring buttons, and laminating and bonding. It is designed to accurately position the seat at the time of use.

Examples of the invention Examples of the present invention are shown in FIGS. 4-10.

FIG. 4 shows the green sheet 1 with completed pier holes. The holes are made using a punching die, an NC drilling machine, or the like. Hole position accuracy can be suppressed to within ±0.01 mm. At this time, holes that will serve as reference holes for positioning in the next process are also drilled at the same time. In the example, an NC drilling machine is used to form a pier hole 5 with a diameter of 0.2 cage, and reference holes 28A, 28B with a diameter of 0.21111 as reference marks.
28C and 28D were simultaneously perforated in the four corners of a 0.3 mm thick green sheet. Position accuracy between holes is ±0.0111
It is 11.

next! FIG. 5 shows the main parts of an apparatus for carrying out the method of filling conductor paste into a pier hole according to an embodiment of the present invention, in which a positioning table 29 has a sheet mounted on its top surface, It can be moved in each direction for fine adjustments, and can be fixed after adjustment. For this purpose, for example, the table base 129 on which the table 29 is placed and the table 29 can be configured to have fine adjustment relative movement performance. Note that the table 29 is designed so that a sheet can be suctioned and fixed to the top surface of the table using a vacuum suction device (not shown) (in FIG. 5, a dummy sheet 30 is placed on the table 29).
is fixed by suction).

Further, the table base 129 is guided by a guide rail 31 whose axis is horizontal, and is movable rightward from the positioning position (a) shown in FIG. 5 to the working position (b). In this working position (b), the screen 32 is placed directly below the screen 32 which is moved up and down, and the screen 32 is lowered into close contact so that the opening 132 matches the peer hole of the sheet.
The conductive paste 33 fills the opening 32 with the lateral movement of the squeegee 34.
It is designed to be pushed through and into the seat's pier hole.

The opening 132 of the screen 32 is the pier hole 5 in FIG.
and the same pattern as the reference holes 28A to 28D.

Above the table 29 at the positioning position, four image pickup tubes 35A to 35D are arranged so as to be able to move slightly in the X and Y directions so as to project the reference mark of the sheet on the table 29 onto the cathode ray tube of the monitor television 36. On the cathode ray tube, the images from the four image pickup tubes 35A to 35D are divided into four parts and projected respectively. On the four divided cathode ray tubes 37A to 37D, two cursor lines 39 can be moved separately in the horizontal and vertical directions.

Next, a method for filling conductive paste into a pier hole according to an embodiment of the present invention will be explained using FIG. 5. First, a method for detecting the screen position will be described. Positioning table 29 stopped at seat positioning position 1a)
A dummy sheet 30 for detecting the position of the screen 32 is mounted on the holder and fixed to the table 29 by vacuum suction.

Next, the table 29 is sent to the working position (b) # along the guide rail 31 of the conductor filling device. Next, squeegee 3
4, print the conductive paste 33 on the dummy sheet 30 through the opening 132 of the screen 32,
Return the table 29 to the positioning position (a) again.

Next, a positioning reference hole 28A which is a reference mark.

28B, 28C, 28D Above the corresponding print patterns 34A, 34B, 34C, 34D, there are image pickup tubes 35A, 35B for position detection.

Make sure that 35C and 35D come. Image pickup tubes 35A, 35
Print pattern 34A imaged in B, 35C, 35D,
Each image 38A of 34B, 34C, 34D,
38B, 38C, and 38D are the corridors 7AasA, 3sB, and a divided into four on the cathode ray tube of the monitor television 36.
Adjust and lock the positions of sc' and 3sp individually in the XY directions. Next, each area 37A, 37B on the cathode ray tube
, 37C, 37D, two horizontal cursors and two vertical cursors I! lli! 39 to surround the print pattern images 38A, 38B, 38C, and 38D from the top, bottom, left, and right. In this embodiment, one image magnified 100 times is displayed on a 12-inch cathode ray tube. Since the scanning line p interval is about 0.6 mm on a cathode ray tube, the solution + y degrees is 0.6 mm.
006 interval aLr), 10, 01m+11 (7) aJ! [
'J quasi-hole (/,) The position of the print pattern can be fixed on the CRT with a cursor line.

Next, we will describe the procedure for filling a product sheet with pier holes with a conductor. Using the end face of the product sheet or a guide hole (not shown), place the product sheet on the positioning table 29 at the positioning position i8) in FIG.
After rough positioning, mount it and fix it using vacuum suction. At this time, the reference holes 28A and 28 were projected on the cathode ray tube.
B.

The images of 28C and 28D are 4QA, as shown in FIG.
40B.

40C and 40D, and the corresponding cursor line 3
It is shifted from the center position of 9. In order to correct this deviation, images 40A and 40 of the reference holes are placed on the cathode ray tube.
While looking at B, 40C, and 40D, find the corresponding force・-
Move the table 29 slightly so that it is in the center of the vine line,
Blocks when positioning is completed. FIG. 7 shows an image of the state in which positioning is completed.

Next, the table 29 is transported to the conductor filling work position (b), stopped at a fixed position, and conductor filling is performed. Subsequently, the table 29 is again conveyed to the positioning position (al), and the sheet with completed conductor filling is taken out.In this way, by adopting the positioning method of the present invention, the feeding accuracy of the table 29 is kept within the range of 0.01 mm. This made it possible to align the screen and sheet with an accuracy of ±0.01111.

Next, the wiring pattern is printed, but since the wiring pattern can be printed using exactly the same device as the conductor filling device (only the screen 32 has been changed), the wiring pattern can be printed at ±0 with respect to the standard position of the sheet. Printing was possible with a positioning accuracy of .0111.

This has made it possible to manufacture a multilayer ceramic substrate with an ultra-high density pattern in which the distance between the end faces of the peer hole conductor and the adjacent wiring line is 0.1 mm.

Next, an example of the lamination adhesion method will be described with reference to FIGS. 8 to 10. This laminating apparatus uses a positioning table 41 configured similarly to the conductor filling apparatus, and this table 41 is similarly movable along the guide rail 31 from the positioning position (a) to the laminating work position (b). There is. In this working position (b), the head section 44 is guided by four guide posts 43 erected on the base 42 and moves up and down vertically. The lower surface 45 of this head portion 44 can attract a sheet by vacuum suction.

Note that four image pickup tubes 35A to 35 are placed on the positioning position (a).
D is arranged and the state in which each is connected to a monitor television is the same as in each of the above embodiments.

Next, we will explain the lamination work using this lamination device.The principle of positioning is the same as that of the conductor filling device.
are fixed one by one on the table 41 at the positioning position, the reference holes 28A to 28η are imaged on the cathode ray tube, the table 41 is adjusted and locked so that the reference holes 28A to 28η are in the fixed position, and the stacking operation is started. It is transported to position (b) and laminated and bonded. To explain step by step, first, the first sheet 1 is roughly positioned and mounted on the positioning table 41 using its end surface or guide hole (not shown in FIG.
Fixed to. Similar to the conductor filling device, the reference hole 28 of sheet 1
Above A, 28B, 28C, and 28D, an image pickup tube 35A,
35B, 35C, and 35D, respectively, and place the reference holes 28 on the cathode ray tube (not shown) of the monitor TV.
A, 28B, 28C, 281) images are projected. Next, the image of each reference hole is fixed on the cathode ray tube using two cursor lines in the vertical direction and two in the horizontal direction. Next, the positioning table 41 is conveyed to the stacking work position (b) while the sheet 1 is vacuum-suctioned, and stopped at a fixed position as shown in FIG. Next, the head portion 44 of the laminating device is lowered along the guide post 43, and the head lower surface 45 is aligned with the sheet 1.
Stop with slight pressure on the top surface.

In this state, the vacuum suction by the table 41 is cut off, the head section 44 is brought into a vacuum suction state, and the sheet 1 is suctioned onto the lower surface 45 thereof. Subsequently, the head portion 44 is retreated upward, and the table 41 is retreated to the positioning position (a).

Next, the means for positioning and stacking the second sheet under the first sheet will be described. ``The second sheet is approximately positioned and fixed on the table 41 at the positioning position (a). Brush or spray adhesive for temporary bonding onto the four corners of the sheet, preferably outside the product area. Next, project the images of the four reference holes on the sheet onto the cathode ray tube, and move the X, Y, Finely adjust the table 41 in the 0 direction and lock it. Next, the table 41 is moved to the stacking work position (b) GC
The sheet is conveyed, the head 44 is lowered, and the lower surface of the first sheet sucked by the head lower surface 45 lightly presses the upper surface of the second sheet, and the sheet is stopped. In this state, table 4
When the vacuum suction of 1 is cut off and the head 44 is raised, 2
The second sheet is adhered to the lower surface of the first sheet and rises. Subsequently, the table 41 is conveyed to the positioning position (a), and the third, fourth, etc. sheets are successively laminated and bonded using the same means as described above until a predetermined number of sheets have been bonded.

In Figure 1θ, the first sheet IA and the second sheet IA
Finished gluing, 3t? Position the seam B of the eye (a
) is shown mounted on a table 41. As can be seen from the explanation below, according to the present invention, the positioning accuracy is determined by the positional accuracy of the reference hole, its resolution, the alignment accuracy with respect to the cursor line on the cathode ray tube, and the mechanical accuracy of the laminating device. Positional deviation error: ±0.01 to ±0
．． Limited to 0.021ml.

Controlled lamination adhesion is possible.

After the sheets have been laminated and bonded, the vacuum suction of the head section 44 is cut off, and the sheets are taken out from the lamination apparatus. In this state, the product is temporarily bonded with adhesive, so the product part is then cut out using the reference hole as a guide and sintered in a sintering furnace. Then Ni
The substrate is completed by performing surface treatment such as plating and Au plating.

In this way, in each example, the edge of the green sheet.

There is no need to abut the surface against the positioning block of the device or insert the guide hole of the green sheet into the guide bin of the device. Therefore, the positioning accuracy will not be deteriorated due to damage to the end face of the green shift or the guide hole.

In addition, since the image of the reference hole of the green sheet is always projected on the cathode ray tube and the position is confirmed during work, if the reference hole position is misaligned due to deformation of the sheet, etc.
It is possible to reject the product as a defective product before starting the work.

In addition, if the reference hole position deviates from within the allowable range due to economical shrinkage of the sheet,
By installing it in a corner and evenly distributing the deviation from the set position on the cathode ray tube in the upper, lower, left and right directions, positional deviation errors can be minimized. With the conventional guide hole and guide bin method, it was impossible to eliminate positional errors caused by parallel movement or rotation of the entire sheet in two directions, but with this method, positioning by parallel movement, rotation, etc. Errors can be minimized because the position is confirmed on the cathode ray tube.

Although the above embodiments have been explained in which the present invention is applied to filling conductors into peer holes, printing wiring stamps, and laminating adhesives, it is of course possible to apply the present invention to only any of the above operations. It is possible.

As described in detail, in the present invention, a table on which a sheet is mounted is movable from a positioning position to a working position, and at the positioning position, one image of reference marks provided at at least two places on the sheet is displayed on a monitor television, After finely adjusting the table so that it is in the specified position on the TV, fix it.
Next, it moves to the working position and performs work such as filling the conductor into the seat pier hole, which has the effect of greatly improving the positioning accuracy of these works and making it possible to obtain an ultra-high precision multilayer board9.

[Brief explanation of the drawing]

Figures 1(a) to 5) are perspective views showing the conventional manufacturing method of ceramic substrates, and Figure 2 is fclf showing the conventional conductor filling process.
Figure 3 is a sectional view showing the conventional lamination bonding process, Figure 4 is a cross-sectional view showing the conventional lamination bonding process.
The figure is a perspective view of a sheet used in an embodiment of the present invention, FIG. 5 is a schematic diagram showing a conductor filling method according to an embodiment of the present invention, and FIG.
The figure is an image of the sheet reference hole before positioning according to the embodiment of the present invention, and FIG. 7 is an image of the sheet reference hole after positioning is completed.
FIG. 8 is a perspective view showing the state in which the first sheet is mounted on a table using the lamination bonding method of the embodiment of the present invention, and FIG. 9 is a perspective view showing the state in which the first sheet is moved to the lamination work position. , FIG. 10 is a perspective view showing a state in which the adhesion of two sheets is completed and the third sheet is at the positioning position. 1...Green sheet 5...Pier hall 29...
・Positioning table 32...Screen 33...Conductor paste 35A to 351)...Imaging tube 36...Monitor television 37A to 37D...Cathode ray tube 39...Cursor line 41...Table 44・
・・Head section O-hat Cl7) 2nd mouth 2 3rd mouth O'7's error (α) O10 country 4

Claims (1)

[Claims] (The table on which the sheet is mounted can be moved from the positioning position to the working position, and at the positioning position, images of reference marks provided at at least two places on the sheet are projected on a monitor television, and the images of the reference marks provided in at least two places on the sheet are displayed on the television, and the table is moved to the specified position on the television. A method for manufacturing a ceramic substrate, which comprises finely adjusting a table, fixing it, then moving it to a working position, and performing work such as filling conductors into seat pier holes, printing wiring stamps, and laminating and adhering.