JPH01302802A - Printed resistor - Google Patents

Abstract

PURPOSE:To grasp the start position of a trimming of a resistor more accurately than in the prior art and make it possible to improve workability by providing an insulator capable of discriminating between an irradiated portion and a non-irradiated portion, adjacent to a resistor through irradiation with laser beams. CONSTITUTION:This device includes a resistor 11 formed by printing, conductors 13, 14 which partially overlap the resistor 11 along the end thereof and provided facing each other, and an insulator 15 provided in a region between these conductors 13, 14 and capable of discriminating between an irradiated portion and nonirradiated portion through irradiation with laser beams. For example, the resistor 11 is formed by printing on a white insulation substrate 12 made of alumina, and on one end thereof are provided the two conductors 13, 14 which overlap the resistor 11 partially. Further, a brown insulation paste layer 15 as an insulator is formed in contact with the resistor 11 in a portion of the region between the conductors 13, 14 or in vicinity of the region.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to improvements in printed resistors used in hybrid integrated circuits and the like.

(Prior Art) Conventionally, a printed resistor having a structure shown in FIG. 3, for example, is known.

1 in the figure is a resistor formed on the insulating substrate 2 by printing. At one end of this resistor l, there are two conductors 3.
4 is provided to partially overlap the resistor l.

In a printed resistor having such a structure, when trimming the resistor l, first laser beam is applied to the substrate portion Q slightly outside the approximate center (starting position HP) of one end of the resistor 1 located between the conductors 3 and 4. After estimating the starting position by irradiating the beam, trimming is performed using a laser beam in the six directions of arrows from the starting position @P.

However, according to the prior art, when trimming,
Even if a portion of the substrate slightly outside the starting position P is irradiated with a laser beam, it is difficult to accurately grasp the irradiation starting position P because the irradiated portion of the substrate and the non-irradiated portion of the substrate are the same in color. Therefore, it takes a lot of time to search for the starting position P, reducing work efficiency. Moreover, there is a possibility that trimming may occur from another resistor part.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and it improves workability by accurately grasping the starting position of trimming of low-resistance elements compared to the conventional method. It is an object of the present invention to provide a printed resistor that can grasp the starting position more accurately than before and improve workability.

[Structure of the Invention (Means for Solving the Problems)] The present invention includes a resistor formed by printing, a resistor that partially overlaps the resistor along the end of the resistor, and faces each other. and an insulator which is provided in close proximity to the resistor in a region between these conductors and whose irradiated portions and non-irradiated portions can be distinguished by irradiation with a laser beam. The gist is:

In the present invention, the conductor may be formed close to the resistor, but it is more preferable to form the conductor in contact with the resistor because the trimming start position can be determined more accurately.

Furthermore, since insulating substrates are often made of alumina or the like, the color of the substrate tends to be white. Therefore, in this case, if the insulator is colored black or brown, it will be easy to accurately identify which part of the insulator is the part of the substrate exposed by laser beam irradiation. Note that if the insulator is not formed directly on the substrate but is formed via another insulating layer, and the power of the laser beam can be adjusted to expose the surface of the insulating layer, the insulator and A similar effect can be obtained by making the insulating layers symmetrical in color.

(Function) In the present invention, due to the presence of an insulator, the irradiated part burns and the surface of the underlying insulating substrate or other layer is exposed, and if the color of the substrate or underlying layer is different from that of the insulator. , the irradiated portion can be separated from the non-irradiated portion. therefore,
The starting position of resistor trimming can be grasped more accurately than before, and work efficiency can be improved.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to FIG.

11 in the figure is a white insulating substrate 1 made of alumina, for example.
2 is a resistor formed by printing. This resistor 1
At one end of 1, two conductors 13, 14 are connected to the resistor 11.
It is provided with a partial overlap. In a part of the region between the conductors 13 and 14 and in the vicinity of this region, an insulating paste layer 15 of, for example, brown color is formed as an insulator in contact with the resistor 11.

According to the printed resistor according to the above embodiment, the conductor 13.14
Since the structure is such that a brown insulating paste layer 15 as an insulator is formed in contact with the resistor 11 in a part of the region between and in the vicinity of this region, the laser beam is not directed to the insulating paste layer 15. When irradiated, the irradiated area burns, exposing the white insulating substrate. Therefore, the irradiation position of the laser beam can be accurately determined by distinguishing between the irradiated white substrate part and the non-irradiated part of the brown insulating paste layer 15, and the trimming start position of the resistor 11 can be determined more accurately than before. It is possible to improve work efficiency by understanding the

In addition, in the above embodiment, the case where the insulator is in contact with the resistor was described, but the case is not limited to this, for example,
As shown in FIG.
It may be close to the region between and close to one side of the resistor 11 having the trimming start position P.

Further, in the above embodiment, a case was described in which a brown insulating paste layer was formed as an insulator, but the color is not limited to this, and any color may be used as long as it can be distinguished from the substrate or its underlying layer.

[Effects of the Invention] As described in detail above, according to the present invention, the work efficiency is improved by accurately grasping the starting position of trimming of a resistor compared to the conventional method. It is possible to provide a highly reliable printed resistor that can be grasped more accurately and improves workability.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a printed resistor according to an embodiment of the present invention;
FIG. 2 is a plan view of a printed resistor according to another embodiment of the present invention, and FIG. 3 is a plan view of a conventional printed resistor. 11-resistor, 12-insulating substrate, 13.14--conductor, 15.16--insulating paste layer (insulator). Applicant's agent Patent attorney Takeshi Suzue Figure 2

Claims (1)

[Claims] A resistor formed by printing, a conductor partially overlapping the resistor along the end of the resistor and facing each other, and a region between these conductors with the resistor. 1. A printed resistor comprising an insulator which is provided in close proximity to the insulator and whose irradiated portion and non-irradiated portion can be distinguished by irradiation with a laser beam.