JPH0766019A - Trimming method for resistor film - Google Patents

Abstract

(57) [Summary] [Object] To provide a method for trimming a resistor film, which can be used for any purpose and which can perform rough adjustment and fine adjustment in a short time. [Constitution] According to the present invention, electrode pads 2 are provided on two opposite sides.
A method for trimming a rectangular resistor film 4 to which 3 are connected, wherein the resistance value of the resistor film 4 is a starting point 6a on one side 4a of the resistor film 4 and End point 6
forming a substantially U-shaped first trimming groove 6 having b,
Further, a second trimming groove 7 which partially overlaps the first trimming groove 6 and narrows the effective width of the resistor film is formed in the resistor film 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trimming method for a resistor film formed on an insulating substrate.

[0002]

2. Description of the Related Art Conventionally, chip resistors, multiple resistors,
For resistance networks, thick film circuit boards, etc., after a resistor film is formed on an insulating substrate, a part of the resistor film is trimmed by laser light or sandblasting in order to adjust the resistance variation of this resistor film. Had been removed.

As shown in the plan view of the chip resistor of FIG. 4, electrode pads 2 and 3 (corresponding to a circuit pattern in a thick film circuit board) are formed on an insulating substrate 1 and the electrode pads 2 and 3 are formed. After forming the rectangular resistor film 4 so as to straddle, and then forming the first insulating layer 51, the resistance value of the resistor film 4 is set to a predetermined value by trimming means, and then the second film is formed. Insulating layer 52 was formed.

The specific resistance value adjusting process of the resistor film 4 is as follows.
While measuring the resistance value by contacting a resistance value measuring probe with the electrode pads 2 and 3 located at both ends of the resistor film 4,
A substantially U-shaped first trimming groove 6 having a start point and an end point is formed on one side 4a of the two sides of the resistor film 4 to which the electrode pads 2 and 3 are not connected by trimming means such as laser beam irradiation. Form. As a result, the trimming area 6 surrounded by the one side 4a and the trimming groove 6 is formed.
c is separated from the main body of the resistor film 4, and the resistor film 4 is substantially separated.
The effective width of electricity was narrowed.

Further, a scanning cut 8 by a reciprocating laser is applied to a portion where the effective width of the resistor film 4 is substantially narrowed by forming the trimming region 6c to finely adjust the resistance value.

[0006]

However, in the above-mentioned trimming process, the trimming process for fine adjustment forms the scanning cut 8 by the reciprocal irradiation of the laser, which causes a problem that the trimming time is required.

When used as a surge-proof resistor, the folded portion of the reciprocating process of the scanning cut 8 acts substantially the same as the start point and end point of irradiation, so that a high voltage is applied to the resistor film 4. When the current flowed, sparks were sometimes generated.

The present invention has been devised in view of the above-mentioned problems, and can be used for any purpose, and further, a method for trimming a resistor film capable of performing rough adjustment and fine adjustment in a short time is provided. To provide.

[0009]

According to the present invention, there is provided a resistor film having a rectangular shape in which electrode pads are connected to two opposite sides, and the resistance value of the resistor film is ( a)
An outline U having a start point and an end point on one side of the two sides of the resistor film to which the electrode pads of the resistor film are not connected
A step of forming a first V-shaped trimming groove and performing rough adjustment; and (b) a part of the resistor film overlapping the first trimming groove and parallel to the side of the resistor film to which the electrode pad is connected. This is a method of trimming a resistor film that is trimmed to a predetermined resistance value by forming a second trimming groove that narrows the effective width in the direction and performing fine adjustment.

[0010]

According to the method of trimming a resistor of the present invention, the first trimming groove for coarse adjustment and the second trimming groove for fine adjustment are formed in the body of the resistor film so as to partially overlap each other. Therefore, basically, it is possible to adjust to a predetermined resistance value with two trimming grooves, and it is possible to achieve trimming in a short time.

Further, since the groove start point, end point and folding point of the trimming groove do not exist in the body of the resistor film, not only ordinary thick film circuit boards and chip resistors but also surge protection Unlike the resistor of No. 1, no spark is generated even when a high-voltage current flows, and the limitation due to the application is greatly eased.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of trimming a resistor according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a plan view of a chip resistor to which the present invention is applied, and FIG. 2 is a sectional view.

In the figure, 1 is an insulating substrate, 2 and 3 are electrode pads including terminal electrodes, 4 is a resistor film, 5 is an insulating protective film, 6 is a first trimming groove, and 7 is a second trimming groove. is there.

The insulating substrate 1 is made of a rectangular ceramic or the like, and has Ag-based conductor electrode pads 2 and 3 formed at both ends thereof. Specifically, it is formed by printing and baking an Ag-based conductor paste. Further, a rectangular resistor film 4 is formed between the two electrode pads 2 and 3 so as to overlap and connect to a part thereof. Specifically, it is formed by printing / baking a resistor paste such as ruthenium oxide.

Further, an insulating protective film 5 having a two-layer structure 51, 52 is formed so as to cover the resistor film 4. The insulating protective film 5 is formed by printing and baking an insulating glass paste.

In the above-mentioned resistor film 4, trimming grooves 6 and 7 are formed by a trimming means such as a laser beam or sand blast in a trimming process in order to set a characteristic such as a resistance value to a predetermined value. Specifically, after forming the resistor film 4 and further forming the first insulating layer 51 on the resistor film 4, trimming for coarse adjustment and trimming for fine adjustment are performed.

Although not shown in the figure, the above-described method for manufacturing the chip resistor has electrode pads 2, 3 on a large substrate on which vertical and horizontal dividing grooves are formed so that a large number of insulating substrates 1 can be extracted.
Is formed, a resistor film 4 is formed between the electrode pads 2 and 3, and a first insulating layer 51 is formed on the resistor film 4,
While measuring the probe contact resistance value of the resistance value measuring device on the electrode pads 2 and 3, at least two trimming grooves 6 are formed in a part of the resistor film 4 by a trimming means such as irradiation of a laser beam on the resistor film 4. 7 is formed and adjusted to a predetermined resistance value, a second insulating layer 52 is further formed so as to cover the resistance film 4 whose resistance value has been adjusted, and the large substrate is divided into individual pieces. Create a chip resistor for.

The trimming process described above includes a rough adjusting process for forming the first trimming groove 6 and the second trimming groove 7.
And a fine adjustment step of forming. Each of the trimming grooves 6 and 7 can be formed by a Teradyne trimming device at a laser power of 1.2 W and a scanning speed of 25.91 m / s.

In the step of roughly adjusting the resistance value of the resistor film 4, the start point 6a and the end point are set on one side 4a of the two sides of the resistor film 4 to which the electrode pads 2 and 3 are not connected. 6
This is performed by forming a first U-shaped first trimming groove 6 having b. Here, the region surrounded by the one side 4a and the trimming groove 6 is the first trimming region 6
That is, when the resistor film 4 is separated from the main body, the effective width of the current flowing through the resistor film 4 is narrowed, and the rough adjustment of the resistance value is achieved.

The fine adjustment of the resistance value of the resistor film 4 is performed with the first trimming groove 6 so as to further narrow the portion where the width of the resistor film 4 is substantially narrowed by the first trimming groove 6. This is performed by forming a second U-shaped second trimming groove 7 having overlapping portions.

In the figure, the irradiation start point 7d and the end point 7b for forming the second trimming groove 7 are formed so as to be located on one side 4a of the resistor film 4, respectively. That is,
The second trimming groove 7 traverses the first trimming region 6c from the irradiation start point 7d, and the intersection point with the first trimming groove 6 becomes a substantial groove starting point 7a. This starting point 7a
From the above, the U-shaped tip portion of the second trimming groove 7 is formed to extend to the main body portion of the resistor film 4, and the end point 7b thereof is formed to be one side 4a of the resistor film 4. ing.

Therefore, the first trimming region 6c formed by the first trimming groove 6 and the second trimming region 7c formed by the second trimming groove 7 are substantially effective in the resistor film 4. It is offset and overlaps each other to determine the width.

3 (a) to 3 (c) show another embodiment of the second trimming groove 7, in particular.

In FIG. 3A, the irradiation start point 7d of the second trimming groove 7 is within the first trimming area 6c formed by the first trimming groove 6, and the irradiation start point 7d of the second trimming groove 7 is formed. The starting point 7a is an intersection point with the first trimming groove 6, and the ending point 7b of the second trimming groove 7 is
It is one side 4 a of the resistor film 4.

In FIG. 3B, the irradiation starting point 7d of the second trimming groove 7 is one side 4a of the resistor film 4, and the starting point 7a of the second trimming groove 7 is the first trimming groove 6. And the end point 7b of the second trimming groove 7 overlaps with the end point 6b of the first trimming groove 6.

That is, the second trimming groove 7 is irradiated so that it crosses the first trimming region 6c from the irradiation start point 7d and further the resistor film 4 has a U-shaped tip,
Furthermore, from the portion where the first trimming groove 6 intersects,
It has the same locus as the trimming groove 6 and the end point.

In FIG. 3C, the laser beam starting point in FIG. 3A and the end point of the trimming groove 7 in FIG. 3C are combined.

In the present invention, the laser trimming process basically performed while the probe for measuring the resistance value is brought into contact with the electrode pads 2 and 3 is completed by forming the two trimming grooves 6 and 7. Trimming can be performed in a short time.

Further, each trimming groove 6, 7 does not have a turning point formed by reciprocating irradiation, and the starting point and the ending point of the groove 6, 7 do not exist in the resistor film 4. Therefore, even if it is used as a surge resistant resistor to which a high voltage is applied, sparks and the like do not occur around the trimming grooves 6 and 7, and a stable operation can be achieved.

In the above embodiment, the trimming groove 6,
The start points 6a, 7a and the end points 6b, 7b of 7 may be interchanged.

Although the chip resistor has been described, a predetermined resistor is formed after the resistor film is formed, such as a multiple resistor, a resistor network element, and a thick film circuit board in which the resistor film is formed on the circuit pattern of the insulating substrate. It can be widely applied to electronic parts that have been trimmed to have the characteristics.

[0033]

As described above, according to the present invention, a resistor film having a predetermined characteristic can be obtained by forming at least two trimming grooves, so that the trimming process can be performed in an extremely short time. .

Further, since the resistor film does not have a starting point portion, an end point portion, and a folded back and forth portion which are reciprocally processed, the trimming groove does not have a spark even when used for high voltage surge resistance. This is a method of trimming a resistor in which the use of the resistor is greatly alleviated and the use of the resistor is greatly eased.

[Brief description of drawings]

FIG. 1 is a plan view of a chip resistor according to the present invention.

FIG. 2 is a vertical cross-sectional view of a chip resistor according to the present invention.

3 (a) to 3 (c) are plan views of other embodiments of the present invention.

FIG. 4 is a plan view of a conventional chip resistor.

[Explanation of symbols]

 1 ... Insulating substrate 2, 3 ... Electrode pad 4 ... Resistor film 5 ... Insulating protective film 6 ... First trimming groove 6a .... Starting point of first trimming groove 6b ... Ending point of first trimming groove 6c ... First trimming area 7 ... Second trimming groove 7a ... ... Starting point of second trimming groove 7b ... Ending point of second trimming groove 7c ... Second trimming area

Claims (1)

[Claims] 1. A rectangular resistor film in which electrode pads are connected to two opposite sides, wherein the resistance value of the resistor film is obtained by the following steps (a) and (b): A method of trimming a resistor film, which is trimmed to a predetermined value. (A) A step of roughly adjusting a U-shaped first trimming groove having a start point and an end point on one side of the two sides of the resistor film to which the electrode pads of the resistor film are not connected . (B) Fine adjustment is performed by forming a second trimming groove that partially overlaps the first trimming groove in the resistor film and narrows the effective width in a direction parallel to the side of the resistor film to which the electrode pad is connected. Process.