JPS60241202A - Method of producing film resistor - 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 [Technical Field of the Invention] The present invention relates to a method for manufacturing a film resistor, and more particularly to a method for facilitating the laser trimming process of a resistor formed on an insulating base thereof. .

[Technical background of the invention]

As is well known, in recent years, hybrid integrated circuits have been increasingly used in order to reduce the size and weight of electronic devices and the like. This hybrid integrated circuit is generally constructed by soldering chip type passive elements or active fr++ elements without lead wires to a thick film substrate made by printing a conductive material and a resistive material on an insulating substrate.

FIG. 1 is for explaining a conventional manufacturing method of such a thick film substrate. That is, as shown in FIG. 1(b), a pair of wiring conductor layers 12.degree. 12 are formed on an insulating substrate 1 made of a ceramic material such as alumina, as shown in FIG. 1(,). . This wiring conductor layer 12.
12Fi, for example, by printing and firing a conductive paste containing silver-noyaradium (Ag/Pd) powder using a screen printing method.

Then, as shown in FIG. 1(c), the pair of wiring conductor layers 12.1! In between, for example, ruthenium oxide (RuO2
) The resistor 13 is formed by printing and firing a resistance yeast (for example, modified nitrile film) containing powder and glass frit using a screen printing method.

Thereafter, as shown in FIG. 1(d), the wiring conductor layer 1
2. A YAG laser is irradiated to the overlapped portion 6 of the resistor 13 and the resistor 13, and the resistor 13 is carbonized to form the wiring conductor layer 1.
Connection portion 14.14 that connects 2.12 and resistor 13
〇In this case, in order to finally obtain the desired resistance value (hereinafter referred to as final resistance value) for the resistor 13, one stroke is used for the resistor having an appropriate sheet resistance value. The width (W) and length L) are designed and formed in advance so that the resistance value (hereinafter referred to as initial resistance value) is equal to or less than the final resistance value. And then, the first
As shown in FIG.
A high-power laser beam capable of scattering O2) powder is irradiated inward from the side of the resistor 13 in the shape of a loop to create a width (W')
A so-called trimming step is performed to reduce the width (W) of the resistor 13 and increase the resistance value to obtain the final resistance value.

In addition, FIG. 2 shows the cutting amount (W ratio (W/W [%] ”) and the rate of change in resistance value (W) with respect to the width (W) of the resistor 13.
It shows the relationship with P[%D], and it can be seen that as the width (W) of the resistor 13 decreases, the resistance value increases.

Here, FIG. 3 shows means for carrying out the above-mentioned trimming step. That is, as described above, the insulating substrate 11 on which a plurality of wiring conductor layers 12 and resistors 133 are formed is installed in the probe guard 15. Then, the end portions of the plurality of gloves 16 fixed to the glove guard 15 are brought into contact with each wiring conductor layer 12, and the resistance value is measured. Thereafter, while measuring the resistance value, the resistor 13 is irradiated with a laser beam 18 from the Radhe light source section 17 so that the resistance value matches the final resistance value, thereby performing laser trimming.

[Problems with background technology]

However, since the material of the globe 16 is generally a metal material such as beryllium copper or brass, the laser beam 18 is irradiated onto the resistor 13 in the shadow of the globe 16, as shown in FIG. This causes a problem in that laser trimming becomes impossible.

In addition, as the resistor 13 has become more densely packaged, especially in recent years, the glove 16 during radar trimming has become more difficult.
Although the number of globes 16 will naturally increase, the number of globes 16 that can be installed at one time in order to secure the optical path of the laser beam 18 will naturally be limited. For this reason, resistor 1
3 is mounted with high density, multiple probe guards 15 are prepared and the resistor 13 is laser trimmed in multiple steps, which makes the work complicated and unsuitable for mass production. Met.

[Purpose of the invention]

This invention was devised in consideration of the above circumstances, and makes it possible to freely take the optical path of the laser beam without being hindered by the probe, for example, when laser trimming a resistor, thereby effectively facilitating mass production. It is an object of the present invention to provide an extremely good method of manufacturing a film resistor that can accelerate the production of film resistors.

[Summary of the invention]

That is, the method for manufacturing a film resistor according to the present invention includes a first step of forming a wiring conductor layer on one surface of an insulating substrate having optical transparency, and a step of forming a wiring conductor layer on the wiring conductor layer after this first step. a second step of forming a resistor to be connected; and a third step of performing laser trimming by irradiating the resistor with laser light from the other side of the insulating substrate after the second step. With this, when trimming the resistor, for example, there will be no interference from gloves, etc.
This allows the optical path of the Rede light to be taken freely, thereby effectively promoting mass production.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. In FIG. 4, the same parts as in FIG. 1 are indicated by the same symbols, and only the different parts will be described here. That is, the insulating substrate 11 is formed of a material having high heat resistance and light transmittance, such as quartz glass, and each wiring conductor layer 12 and each resistor 13 of this insulating substrate 1 is formed. The difference from the conventional method is that the resistor 13 is irradiated with the radar light 18 from the surface opposite to the surface where the resistor 13 is exposed. According to such a configuration, the laser beam 18 can be transmitted through the insulating substrate 11 to trim the resistor 13.

Therefore, the optical path of the laser beam 18 is not obstructed by the Zorope 16, and the optical path can be freely planned, making it possible to easily mass-produce thick film substrates on which the resistors 13 are mounted at high density. .

Here, in the above embodiment, it has been described that laser trimming is performed in the direction of increasing the resistance value of the resistor 13, but the resistance value can also be decreased by using the means described below. That is, as shown in FIG. 5(b), a pair of wiring conductor layers are placed on an insulating substrate 1 made of a highly heat-resistant, light-transmitting material such as quartz glass as shown in FIG. 5(,). 12.12 is formed.

This wiring conductor layer 12.12 is made by printing a conductor yeast containing, for example, silver-iR oxide powder (Ag/Pd) using a screen printing method, and baking it for 10 minutes at a peak temperature of 850 [°C]. It is formed by

Then, as shown in FIG. 5(C), for example, ruthenium oxide (RuO2
) The resistor 13 is formed by printing a resistive coating (e.g. modified nitrile rubber) containing powder and glass frit using a screen printing method and firing it for 10 minutes at a peak temperature of 850 [°C]. do. After that, Fig. 5(d)
), the overlapping portion of the wiring conductor layer 12.12 and the resistor 13 is irradiated with a YAG laser to carbonize the resistor 13, thereby forming the wiring conductor layer 12.12 and the resistor 1.
A connecting portion 14° 14 is formed to provide electrical continuity between the two.

Here, as shown by hatching in FIG. 5(,), a low-power YAG laser is applied to the resistor 13 so as not to scatter its glass component and conductor particles, that is, ruthenium oxide (RuO2) particles. When the laser beam is irradiated back and forth between the wiring conductor layers 12 and 12, the resistance value (initial resistance value) of the resistor 13 can be reduced in accordance with the number of laser irradiations. The reason for this is that when the resistor 13, which has been sintered on the insulating substrate 11, is irradiated with the above-mentioned low-power YAG l/- laser, ruthenium oxide (RuO2) particles, which are conductive particles, and glass The components are separated,
This is because the conductor particles gather together and the conductor layer of the resistor 13 is promoted. In this case, as a YAG laser, for example, the output is 151 AI, the irradiation speed is
Experimentally, good results were obtained when the surface of the resistor 13 was irradiated under the condition of 30 [m/see] O.

Here, Figures 6 to 8 show the number of YAG laser irradiations and the resistance value (6) obtained experimentally, respectively.
It shows the relationship between In other words, Fig. 6 shows the case where a YAG laser is irradiated to a resistor with a sheet resistance value of 100 [Ω], and the resistance value, which was 120 [Ω] before laser irradiation, changes depending on the number of irradiations. The resistance decreased to 20 [Ω] after polishing five times. In addition, Figure 7d shows the case where a YAG laser is irradiated on a resistor with a sheet resistance value of 10 [kΩ], and the resistance value, which was 11 [kΩ] before laser irradiation, becomes 3 after 5 times of irradiation. It decreased to .5 [kΩ]. Furthermore, FIG. 8 shows that the sheet resistance value is 100
(kΩ) resistor, YAG laser 4
After irradiation, the resistance value decreased to Fi35 [kΩ].

Then, the resistor 1 is irradiated with the YAG laser as described above.
The resistance value reduction characteristic 3 can be changed as appropriate by changing the irradiation output and irradiation speed of the YAG laser, and the resistance value of the resistor 13 can be reduced over a wide range. be. Further, the resistance value can be reduced regardless of the film thickness of the resistor 13.

Therefore, by selectively using the process of reducing the resistance value of the resistor 13 by irradiating the resistor 13 with the low-power YAG laser as described above and the trimming process (that is, increasing the resistance value) described above, it is possible to reduce the resistance value of the insulating substrate 1. Regardless of whether the initial resistance value of the printed and fired resistor 13 is higher or lower than the final resistance value, the resistor 13
The resistance value of the resistor can be made to match the final resistance value. That is, as shown in FIG. 9, when the initial resistance value of the resistor 13 reaches a value (R1) higher than the final resistance value (Ro), the resistance value is decreased by low-power YAG laser irradiation and the final resistance value is reduced. If the initial resistance value of the resistor 13 is lower (R8) than the final resistance value (Ro), the resistance value is increased by the trimming process and the final resistance value is increased. If it is possible to approach the value (Ro), the control range for the initial resistance value of the resistor 13 can be made wider than in the past, and the yield V can be improved. For example, in order to obtain a desired initial resistance value, it is no longer necessary to strictly specify the width and length of the resistor 13 and print it, and all the resistors 13 on the scale can be printed in the same shape. This is because it can be stored away, making manufacturing extremely easy.

Further, in mass production, the conventional steps such as trial firing of the resistor 13 are no longer necessary, and mass production can be effectively promoted. Additionally, resistor 1
In order to improve the printing accuracy of the resistor 13, the resistor 13 can also be formed by printing at the beginning of the printing process. That is, even if the resistance value of the low antibody 13 increases due to the firing process of other parts after the resistor 13 is formed, the resistance value can be decreased later.

Here, the output of the above-mentioned YAG laser requires about 2 seconds for resistance value reduction and trimming process, but this can be done by switching the current value flowing through the pumping lamp of the YAG laser generator itself to achieve high output and low output. By controlling the number of irradiations, irradiation speed, irradiation distance, etc. of the high-output YAG laser for the trimming process, it is also possible to use it for reducing the resistance value. The YAG laser for primary and resistance value reduction is the 5th
As shown in the figure (@), the resistor 13 may be scanned not only in the horizontal direction in the figure, but also in the diagonal and vertical directions. It is also possible to scan in a grid pattern or crank pattern in combination with directional scanning, or to irradiate the entire surface of the resistor 13 at once.

It should be noted that the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist thereof.

〔Effect of the invention〕

Therefore, as detailed above, according to the present invention, when laser trimming a resistor, it is possible to freely take the optical path of the laser beam without being hindered by, for example, a probe, etc., thereby effectively facilitating mass production. It is possible to provide an extremely good method of manufacturing a film resistor that can be accelerated.

[Brief explanation of drawings]

FIG. 1 is a plan view for explaining a conventional film resistor manufacturing method, FIG. 2 is a characteristic curve diagram for explaining the trimming process of the conventional film resistor manufacturing method, and FIG. FIG. 4 is a perspective view showing an embodiment of the method for manufacturing a film resistor according to the present invention, and FIG. 5 is a perspective view showing a means for performing the conventional trimming process. FIG. A plan view for explaining the means, FIGS. 6 to 8 are characteristic curve diagrams showing the number of laser irradiations and changes in the resistance value of the resistor, respectively, and FIG. 9 is a diagram showing the resistance value of the same example. It is a figure for explaining a correction means. 11... Insulating substrate, 12... Wiring conductor layer, 13...
- Resistor, 14... Contact part, 15... Probe guard, 16... Probe, 17... Laser light source part, 1
8...Laser light. Applicant's agent Patent attorney Takehiko Suzue Figure 5 (a) (, b) Figure 6 Figure 7 Figure 9 L-Desho! 1 trimisig

Claims (1)

[Claims] A first step of forming a wiring conductor layer on one surface of an insulating substrate having light transparency, and forming a resistor connected to the wiring conductor layer after this first step. and a third step of performing laser trimming by irradiating the resistor with a laser beam from the other four sides of the insulating substrate after the second step. Characteristic method for manufacturing membrane resistors.