JPH0529391A - Manufacture of thick film circuit board - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing a thick film circuit board having excellent features, which has a simple line structure and a small facility investment amount, and can suppress dispersion of exhibiting resistance value of a formed resistor to a small value. CONSTITUTION:First, thick film resistor paste is printed on an alumina board 1, dried, then thick film Ag/Pt paste is printed, dried as it is without baking, both dried films are simultaneously baked to form electrodes, wirings for connecting a semiconductor chip, component lands 2 and a resistor 3 at the same time, then thick film overcoating glass is printed, dried and baked to form a circuit protecting overcoating glass 4. Thus, large effects can be realized at the points of a line structure, a facility investment amount, dispersing degree of exhibiting resistance value of the resistor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thick film circuit board for mounting electronic components, which can be used when a semiconductor chip is mounted by solder connection in a face-down method.

[0002]

2. Description of the Related Art In recent years, as a method for manufacturing a thick film circuit board, in response to an increasing need for mounting a semiconductor chip by solder connection in a face-down method, it has excellent solder wettability and solder resistance as a conductor material. In addition, a method of using a thick film Ag / Pt paste, which is advantageous in terms of cost, is often used.

A conventional method for manufacturing a thick film circuit board will be described below. FIG. 2 shows a cross-sectional view of a thick film circuit board using a conventional manufacturing method. In FIG. 2, 1 is an alumina substrate, 2 is a semiconductor chip connecting electrode, wiring, and component land, 3 is a resistor, and 4 is a circuit protection overcoat glass.

A method of manufacturing the thick film circuit board having the above structure will be described below in detail. First, a thick film Ag / Pt paste is printed and dried on the alumina substrate 1 and baked to form electrodes for semiconductor chip connection, wiring, and component lands 2. Subsequently, the thick film resistor paste is printed and dried, and then fired to form the resistor 3. Further, the thick film glass paste is printed and dried, and then fired to form the circuit protection overcoat glass 4.

[0005]

However, in the method of manufacturing a thick film circuit board having the above-mentioned structure, since there are as many as three baking steps in the manufacturing process, the manufacturing line is redundant and the capital investment is large. Since the thick film resistor paste is printed on a film surface having a problem and having a very large undulation after the electrodes for connecting the semiconductor chip, the wiring, and the component land are formed, the dispersion of the resistance value appears very much. It also had the problem of becoming larger.

The present invention solves the above-mentioned conventional problems, and has a simple line structure, a small amount of capital investment, and a small dispersion of the resistance value of the formed resistor. An object is to provide a method for manufacturing a circuit board.

[0007]

In order to achieve this object, a thick film circuit board manufactured by the method of the present invention is as follows. / Pt paste is printed and dried, and both dried films are simultaneously fired to form electrodes for semiconductor chip connection, wiring, component lands, and resistors all at once, and then thick film overcoat glass is dried by printing and fired. It has a structure of forming an overcoat glass for circuit protection.

[0008]

In the method of manufacturing the thick film circuit board having this structure,
Since there are only two firing processes in the manufacturing process, the line configuration is simple and the capital investment can be reduced.
Further, since the thick film resistor paste is printed directly on the alumina substrate with less undulation before the semiconductor chip connecting electrodes, wirings, and component lands are formed, it is possible to suppress the dispersion of the appearing resistance value.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is an alumina substrate,
Reference numeral 2 is a semiconductor chip connecting electrode, wiring, and component land, 3 is a resistor, and 4 is a circuit protection overcoat glass.

A method of manufacturing the thick film circuit board having the above-described structure will be described below in detail. First, the thick film resistor paste is printed and dried on the alumina substrate 1 and then the thick film Ag / Pt paste is directly printed and dried without firing, and both dried films are fired at the same time to form electrodes for semiconductor chip connection, wiring, and component land. 2 and the resistor 3 are formed all at once, and then the thick film overcoat glass is printed, dried, and fired to form the circuit protection overcoat glass 4.

The characteristics of the method for manufacturing the thick film circuit board according to this embodiment and the characteristics of the conventional method for manufacturing the thick film circuit board are shown in Table 1 below.
It shows in comparison with.

[0013]

[Table 1]

As is clear from (Table 1), the method for manufacturing the thick film circuit board according to this embodiment has excellent effects in terms of the line configuration, the amount of equipment investment, and the degree of dispersion of the resistance values of the resistors. can get.

As described above, according to the present embodiment, first, the thick film resistor paste is printed and dried on the alumina substrate 1 and then the thick film Ag / Pt paste is directly printed and dried without firing, and both dried films are formed. Simultaneously baking to form electrodes for semiconductor chip connection, wiring, component land 2 and resistor 3 all at once,
After that, the thick film overcoat glass is printed and dried, and then baked to form the circuit protection overcoat glass 4,
Since the firing process only exists once during the manufacturing process, the line structure is simple and the capital investment can be reduced, and furthermore, there is little undulation before forming electrodes for semiconductor chip connection, wiring, and component lands. Since the thick film resistor paste is printed directly on the substrate, it is possible to suppress the dispersion of the appearing resistance value to be small.

[0016]

As described above, according to the present invention, the thick film resistor paste is first printed and dried on the alumina substrate, and then the thick film Ag / Pt paste is directly printed and dried without firing. Both dry films are simultaneously fired to form electrodes for semiconductor chip connection, wiring, component lands and resistors all at once, and then the thick film overcoat glass is printed and dried and then fired to form the circuit protection overcoat glass. As a result, it is possible to provide an excellent method for manufacturing a thick film circuit board, which has a simple line configuration, requires a small amount of capital investment, and can suppress the dispersion of the resistance values of the formed resistors.

[Brief description of drawings]

FIG. 1 is a sectional view showing a method of manufacturing a thick film circuit board according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional method for manufacturing a thick film circuit board.

[Explanation of symbols]

 1 Alumina substrate 2 Semiconductor chip connection electrodes, wiring, component land 3 Resistor 4 Circuit protection overcoat glass

Claims (1)

Claim: What is claimed is: 1. A thick film for forming at least one of a semiconductor chip connecting electrode, a wiring and a component land after printing and drying a thick film resistor paste for forming a resistor. A method of manufacturing a thick film circuit board, comprising at least a step of printing and drying an Ag / Pt paste and simultaneously firing both the dried film and the dried film.