JPH0195594A - Method for vertically providing pin in ceramic substrate - Google Patents

Abstract

PURPOSE:To improve the bonding intensity of pins by filling the holes of the ceramic green sheet on a ceramic substrate for vertically providing pins with a filler containing a ceramic powder or a glass powder and a conductor, vertically providing the pins in the holes, and calcining the ceramic green sheet and the filler at a temperature lower than the calcination temperature of the substrate. CONSTITUTION:On a ceramic substrate 2, a ceramic green sheet 6 having a calcination temperature lower than that of the ceramic substrate 2 is provided which has throughholes 8 opened in the positions where pins 10 are to be vertically provided, then the throughholes 8 are filled with a filler 12 containing at least either a ceramic powder or a glass powder and a conductor 4 and vertically provided with the pins 10, and under this condition, the ceramic green sheet 6 and the filler 12 are calcinated at a temperature lower than the calcination temperature of the ceramic substrate 2. Accordingly, the pins 10 have their head buried in the ceramic sheet 6 and bonded with the ceramic and glass in the filler 12. With this, the bonding intensity of the pins can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for erecting pins on a ceramic substrate used, for example, in an IC package.

[Conventional technology]

Conventionally, this type of pin installation method is as follows: 1. Forming a conductor pad on the board and soldering or brazing the head of the pin with a flat head to the pad, or 2. Baking. A method has been adopted in which a hole is made on the previous board, the hole is filled with conductive paste, and the board is fired with a bar-shaped pin inserted.

(Problems to be Solved by the Invention) However, in method (2) above, the pad area is larger than the pin diameter, so the mounting density of the pins is limited, and even if the head is provided, the bonding area between the pin and the pad is limited. There are problems such as weak bonding strength of the pins due to the small amount of bonding.

In addition, the above method (■) has problems, such as shrinkage occurring when the board is fired, resulting in poor pin positioning accuracy, and poor bonding strength of the pins due to the difference in thermal expansion between the filled conductor and the board. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for erecting pins on a ceramic substrate that solves these problems.

[Means for solving problems]

In the bottle erecting method of the present invention, a fired ceramic substrate on which pins are to be erected is prepared, and a ceramic green sheet whose sintering temperature is lower than that of the ceramic substrate is placed on the ceramic substrate. A through-hole is provided in the position where the pin should be erected, and the through-hole of the ceramic green sheet is filled with a filler containing a conductor and at least one of ceramic powder and glass powder, and the pin is erected. The method is characterized in that the ceramic green sheet and the filler are sintered in this state at a temperature lower than the firing temperature of the ceramic substrate.

〔Example〕

FIG. 1 is a sectional view for explaining the pin erecting method according to the present invention.

First, a fired ceramic substrate 2 on which the pins 10 are to be erected is prepared. This ceramic substrate 2 is a multilayer ceramic substrate in the illustrated example, and has a conductor 4 for wiring inside, and a part of the conductor 4 has pins 1 on the surface.
0 is exposed at the position where it should be installed. However, this ceramic substrate 2 does not necessarily have to be a multilayer substrate.

As this ceramic substrate 2, for example, BaO3tow
A material made of Alz()+Bz()+thread material is used. Further, as the conductor 4, for example, Ag-Pd5C
Use u etc.

Next, on the ceramic substrate 2, a ceramic green sheet 6 whose sintering temperature is lower than that of the ceramic substrate 2 is penetrated at the position where the pin 10 is to be erected, that is, at the position of the exposed conductor 4 of the ceramic substrate 2. A hole 8 is provided in each case.

The ceramic green sheet 6 may be made of BaO and/or B, for example, rather than the material of the ceramic substrate 2.
20. Use one with a rich composition.

Next, in each through hole 8 of the ceramic green sheet 6,
A filler 12 containing a small amount of ceramic powder and glass powder (one of which is a conductor) is filled by, for example, screen printing.

As this ceramic powder, for example, the same material as the ceramic green sheet 6 is used. As the glass powder, for example, ZnOStow Btus type powder is used. As the conductor, for example, the same material as the conductor 4 is used. Further, the proportion of the conductor in the filler 12 is, for example, about 90 to 80%.

Next, one end of the rod-shaped pin 10 is inserted into each through-hole 8 filled with the filler 12 and made to stand. However, pin 1
The filler 12 may be filled after the 0 is set. In this case, if necessary, for example, a jig 14 for regulating the position of the pin 10 and a weight 16 for pressing the pin 10 may be used, as shown in the illustrated example.
You may also use If the next sintering step is performed using such a material, the positional accuracy of the pin 10 will be further increased because the positional deviation of the pin 10 will be prevented. Direct contact between the pin 10 and the conductor 4 is also improved.

Then, with pin 10 erected as described above,
Ceramic green sheets 6 and filler 12 are sintered at a temperature lower than the firing temperature of ceramic substrate 2. Therefore, the ceramic substrate 2 is not adversely affected by remelting, peeling, etc.

As a result, the ceramic green sheet 6 becomes a ceramic sheet and comes into close contact with the ceramic substrate 2, and the pins 10 are bonded to the ceramic sheet etc. by the filler 12 and mechanically fixed, and the pins 10 and the ceramic substrate 2 are bonded to each other. The surface conductor 4 is electrically connected directly and via the conductor in the filler 12.

〔Effect of the invention〕

As described above, according to the present invention, there is no need to provide the pin with a flat head, and the size of the through hole in the ceramic green sheet may be slightly larger than the diameter of the pin.
Pin mounting density can be increased.

In addition, the head of the pin is embedded in the ceramic sheet and bonded with the ceramic or glass in the filler, and the ceramic sheet and the filler are similar in material and there is a large thermal expansion difference between them. Since there is no adhesive, the adhesive strength of the pin is also increased.

Also, since the ceramic substrate itself is not fired,
Shrinkage of the ceramic substrate during sintering of ceramic green sheets and the like hardly occurs, and therefore pin position accuracy is improved.

Furthermore, since the filler contains a conductor, electrical connection between the conductor on the ceramic substrate and the pin is more reliably achieved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view for explaining the pin erecting method according to the present invention. 2... Ceramic substrate, 4... Conductor, 6... Ceramic green sheet, 8... Through hole, 10... Pin, 12... Filler.

Claims (1)

[Claims] (1) Prepare a fired ceramic substrate on which pins are to be erected, and erect pins on a ceramic green sheet whose sintering temperature is lower than that of the ceramic substrate. A through-hole is provided at the desired position, and the through-hole of the ceramic green sheet is filled with a filler containing a conductor and at least one of ceramic powder and glass powder, and a pin is set up, and in that state. A method for erecting pins on a ceramic substrate, characterized in that the ceramic green sheet and the filler are sintered at a temperature lower than the firing temperature of the ceramic substrate.