JPH0971488A - Production of ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the warpage and deformation caused in baking ceramic substrates at a high temperature by stacking the ceramic substrates having break grooves cut on either of surfaces so as to alternately direct the surfaces having the break grooves upward and downward and baking the stack. SOLUTION: Plural ceramic substrates 1 having break grooves 3 cut on either of surfaces in a state of green sheets are stacked so as to direct each surface with the break grooves 3 of the odd-numbered ceramic substrates 1 counted from the bottom upward and, on the other hand, each surface with the break grooves 3 of the even-numbered ceramic substrates 1 counted from the bottom downward. The resultant stack is then heated at 100-500 deg.C, degreased and further baked at 1,500-1,550 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip resistor formed by forming a resistive film on the surface of a ceramic substrate piece, or
In a thermal print head in which a heating resistor for printing is formed on the surface of a ceramic substrate piece, or in a hybrid integrated circuit in which various electronic parts are mounted on the surface of a ceramic substrate piece, the ceramic substrate The present invention relates to a method for manufacturing a ceramic substrate used for manufacturing a piece.

[0002]

2. Description of the Related Art Conventionally, a ceramic substrate used for manufacturing a ceramic substrate piece for a chip resistor or the like is
It is manufactured by the method as described below. That is, first, as shown in FIG. 5, a break groove 3 is formed on the surface of the ceramic substrate 1 so as to break the ceramic substrate 1 into a large number of substrate pieces 2 in the state of a soft green sheet. Then, in order to improve productivity, a plurality of ceramic substrates 1 are shown in FIG. 6 with their surfaces having the break grooves 3 aligned in the upward direction or in the downward direction. As described above, they are stacked and placed in a heating and firing furnace in this state, for example, about 100 to 5
It is manufactured by heating to a temperature of 00 ° C. for degreasing treatment, and then firing at a high temperature of about 1500 to 1550 ° C., for example.

[0003]

By the way, when firing the ceramic substrate 1 after engraving the break groove 3 in the state of the green sheet at a high temperature, the break groove 3 is engraved on both surfaces of the ceramic substrate. There is a shrinkage difference between the two surfaces so that the surface on the opposite side tends to shrink more than the surface on the opposite side where the break groove 3 is not engraved.

Therefore, as described above, a plurality of ceramic substrates 1 on which the break grooves 3 have been engraved in the state of the green sheets are laminated so that the surfaces with the break grooves 3 are aligned in the same upward or downward direction. In the method of stacking and firing in this stacked state, each ceramic substrate 1 is
Due to the difference in contraction between the two surfaces during the firing, as shown by the chain double-dashed line in FIG. 6, the surfaces provided with the break grooves 3 are simultaneously warped and deformed in a curved direction. Become.

Therefore, conventionally, a ceramic substrate that has been fired at a high temperature has a warp extended flat by placing a weight on the ceramic substrate, and the temperature is slightly lower than the firing temperature (about 1300 ° C.). ), The warp deformation is corrected for all the ceramic substrates, but in the conventional method described above, since the warp in each ceramic substrate is in the same direction, Since the warp deformation is large, in addition to requiring a long heating time to correct the warp deformation described above, when the warp of each ceramic substrate is extended in a flat shape, the ceramic substrate follows a break groove on its surface. Since there is a high frequency of cracking, and therefore the rate of defective products is high, there is a problem that the manufacturing cost is considerably increased.

When the break groove for the ceramic substrate is formed on both the front and back surfaces of the ceramic substrate, the break groove on one surface may be deep and the break groove on the other surface may be shallow. In general, even in this case, conventionally, a plurality of ceramic substrates are stacked in a layered manner with the surfaces having the deep break grooves facing upward or downward,
The stack is fired at a high temperature, but during the high temperature firing, the surface of the ceramic substrate with deep break grooves shrinks more than the surface with shallow break grooves, so that each ceramic A similar problem exists because the substrate warps significantly toward the surface with deep break grooves.

It is a technical object of the present invention to provide a method for manufacturing a ceramic substrate which can reduce the warp deformation that occurs during the firing at the high temperature.

[0008]

In order to achieve this technical object, "Claim 1" of the present invention states that "a plurality of ceramic substrates having a break groove formed on one surface in the state of a green sheet, It is characterized in that the surfaces provided with break grooves are alternately stacked upward and downward so as to be stacked, and in this stacked state, firing is performed at a high temperature. "

In addition, the "claim 2" of the present invention is that "a plurality of ceramic substrates each having a deep break groove on one surface and a shallow break groove on the other surface in the state of a green sheet are deep-breaked. It is characterized in that the surfaces provided with grooves are stacked in a laminated manner so that the surfaces are alternately turned upward and downward, and in this stacked state, firing is carried out at a high temperature. "

[0010]

[Operation] As described in "Claim 1", a plurality of ceramic substrates having break grooves engraved on one surface thereof are laminated so that the surfaces having break grooves are alternately turned upward and downward. By stacking in a stack and firing at a high temperature in this stacked state, the warp deformations that occur in each of the ceramic substrates during firing at a high temperature become opposite to each other between adjacent ceramic substrates, and Since it works to suppress warp deformation, make warp deformation in each ceramic substrate smaller than when stacking multiple breakers in each ceramic substrate with their break grooves aligned upward or downward as in the conventional case. Can be done.

When a deep break groove is formed on one surface of the ceramic substrate and a shallow break groove is formed on the other surface of the ceramic substrate, the surfaces having the deep break grooves are alternately arranged as in "Claim 2". By stacking in a laminated manner so that it faces upward and downward, and firing in this stacked state at high temperature, the warp deformation that occurs in each ceramic substrate during firing at high temperature is Since they are in opposite directions to each other and work to suppress the warp deformation, the warp deformation of each ceramic substrate is increased as in the conventional case, and the deep break groove faces upward. Alternatively, the size can be made smaller than in the case of stacking in a downward alignment.

[0012]

As described above, according to the present invention, the warp deformation generated when the ceramic substrate with break grooves is fired at a high temperature can be reduced, so that the heating time required to correct the warp deformation after firing can be shortened. In addition to this, there are few cracks that occur during correction of warp deformation, and the incidence of defective products can be reduced, which has the effect of significantly reducing the manufacturing cost of the ceramic substrate.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment, which is a case where a break groove is formed only on one surface of a ceramic substrate. That is, when stacking a plurality of ceramic substrates 1 in which the break grooves 3 are engraved only on one surface in the state of a green sheet in a stacked manner, an odd-numbered ceramic substrate 1 among the ceramic substrates 1 is counted from the bottom. So that the surface with the break groove 3 faces upward, while the even-numbered ceramic substrates 1 are turned upside down so that the surface with the break groove 3 faces downward. A plurality of substrates 1 are stacked in a laminated manner such that the surfaces having the break grooves 3 are alternately facing upward and downward, and in this stacked state, a degreasing treatment of heating to a temperature of about 100 to 500 ° C. is performed. After that, about 1500-15
It is fired at a high temperature of 50 ° C.

Then, during the firing at the high temperature, the warp deformations generated in the respective ceramic substrates 1 are opposite to each other between the adjacent ceramic substrates 1.
Since they act to suppress the warp deformations of each other, the warp deformations of the respective ceramic substrates 1 are more likely to occur than in the conventional case where a plurality of ceramic substrates are stacked with their break grooves aligned upward or downward. It can be made smaller.

As described above, since the warp deformation generated in each ceramic substrate 1 is small, the ceramic substrate that has been fired at a high temperature is placed in a flat shape by placing a weight on the ceramic substrate, By heating to a temperature slightly lower than the firing temperature (about 1300 ° C.), the heating time can be shortened considerably when correcting the above warp deformation, and when the warp is extended to a flat surface. It is possible to reliably reduce cracking along the break groove 3.

The second embodiment shown in FIG. 4 is a ceramic substrate 1'in which a deep break groove 3'is engraved on one surface and a shallow break groove 3 "is engraved on the other surface in the state of a green sheet. That is, when stacking a plurality of the ceramic substrates 3'in a laminated form, an odd-numbered ceramic substrate 1'counted from the bottom of each ceramic substrate 1'is provided with a deep break groove 3 '. The upper surface is provided with a shallow break groove 3 ″ so that the surface faces downward, while the even-numbered ceramic substrate 1 ′
Are stacked upside down such that the surface with the deep break groove 3 ′ faces downward and the surface with the shallow break groove 3 ″ faces upward, so that a plurality of ceramic substrates 1 ′ are stacked. ′ Is stacked in such a manner that the surfaces are alternately turned upward and downward, and in this stacked state, a degreasing treatment of heating to a temperature of about 100 to 500 ° C. is performed, and then about 1500 to 1550 ° C. It is fired at the so-called high temperature.

Also in this case, the warp deformations generated in the respective ceramic substrates 1'during firing at a high temperature are opposite to each other between the adjacent ceramic substrates 1 ', and the warp deformations are mutually caused. Since it works to suppress, warp deformation in each ceramic substrate 'should be made smaller than in the case where a plurality of ceramic substrates are stacked with their deep break grooves aligned upward or downward as in the conventional case. Can be done.

[Brief description of drawings]

FIG. 1 is a perspective view of a ceramic substrate according to a method of a first embodiment of the present invention.

2 is a vertical front view of FIG. 1. FIG.

FIG. 3 is a vertical sectional front view showing a stacked state according to the method of the first embodiment of the present invention.

FIG. 4 is a vertical sectional front view showing a method of a second embodiment of the present invention.

FIG. 5 is a perspective view of a ceramic substrate according to a conventional method.

FIG. 6 is a vertical sectional front view showing a stacked state according to a conventional method.

[Explanation of symbols]

 1,1 'Ceramic substrate 2 Substrate piece 3 Break groove 3'Deep break groove 3 "Shallow break groove

Claims (2)

[Claims] 1. A plurality of ceramic substrates each having a break groove formed on one surface in a state of a green sheet are stacked in a laminated manner so that the surfaces having break grooves are alternately turned upward and downward. A method for manufacturing a ceramic substrate, which comprises firing in a stacked state at a high temperature. 2. A plurality of ceramic substrates each having a deep break groove formed on one surface and a shallow break groove formed on the other surface in a state of a green sheet, the surfaces having the deep break grooves alternately facing upward and downward. The method for producing a ceramic substrate is characterized in that the ceramic substrates are stacked in such a manner that