JPH06325913A - Manufacture of chip resistor - Google Patents

Abstract

PURPOSE:To prevent the generation of a blur, a disappearance or the like of a marking by a method wherein a chip resistor is marked by a photolithography method and this marking is covered with a transparent or semitransparent resin protective layer. CONSTITUTION:A resistor layer 2 and an electrode layer 5 are provided on an insulative substrate 1 and after that, the layer 2 is trimmed by a laser or the like and while a trimming groove 7 is formed, the resistance value of the layer 2 is adjusted. Then, a photosensitive resin layer 6 is provided on the layer 2 in such a way that its film thickness is 1 to 10mum or thereabouts. Then, this layer 6 is exposed to light using a mask formed with a prescribed marking pattern, the layer 6 is developed with a prescribed developing solution to leave a marking pattern layer 3 and the layer 6 is removed. A transparent or semitransparent resin protective layer 4 is provided in such a way as to cover the layer 3 and the exposed part of the layer 2. Thereby, even a microscopic marking is made possible a sharp notation and a chip resistor, on which a blur, a disappearance or the like of the marking is never generated, can be manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a chip resistor, and more particularly to a chip-shaped thin film resistor and a method of manufacturing a thick film resistor.

[0002]

2. Description of the Related Art Generally, the surface of a chip resistor (thin film resistor and thick film resistor) is provided with a mark such as a character or mark for identifying a resistance value. Conventionally, the mark is provided by printing such as screen printing, transfer, etc. on a protective layer of glass covering the resistor layer provided on the insulating substrate.

[0003]

However, with the recent miniaturization of electronic components, the chip resistors have also been miniaturized, and the conventional mark forming methods such as printing and transfer cannot be used. Is coming.

For example, in a chip resistor having a shape dimension of 1.6 × 0.8 mm, the actual marking location is 1.0 × 0.6 m.
If the width is about m or less and the width is about 50 μm or more, the description becomes unclear. However, the printing or transfer is
It is unsuitable for fine markings, and blurring or blurring occurs when trying to form a fine line with a width of about 50 μm or less.

Further, since the mark is provided on the surface of the protective layer, the mark surface is exposed. Therefore, if the mark is fine by the thin line as described above, various kinds of marks are used in the process after the mark in the manufacturing process, for example, in the braking process or plating process or the like which is usually performed in the manufacturing process of the chip resistor. The mark may be faint or disappear due to contact or rubbing with a manufacturing device, a case, or the like, or rubbing between parts.

Further, since the mark is provided on the uppermost layer, the unevenness of the mark portion is generated on the surface of the chip resistor.
When the size of the chip resistor is reduced, the unevenness reduces the suction force of the suction collet at the time of mounting and causes mounting failure.

It is an object of the present invention to solve the above problems and to provide a method for manufacturing a chip resistor which enables sharp marking even with a fine marking and does not cause fading or disappearance of the marking. To do.

[0008]

The present inventor has conducted extensive studies in view of the above-mentioned state of the art, and as a result, the marking of the chip resistor is performed by a photolithography method, and the marking is made of a transparent or translucent resin. It has been found that when covered with a protective layer, the pattern of the mark is sharp and easy to read, the mark does not fade or disappear, and the surface of the chip resistor can be made smooth.

That is, the present invention relates to the following method of manufacturing a chip resistor.

(1) A photosensitive resin is applied on an insulating substrate having a resistor layer formed thereon, the photosensitive resin is exposed to light by a mask having a predetermined marking pattern formed thereon, and the mark is developed. A method of manufacturing a chip resistor, comprising forming a pattern, and providing a transparent or semitransparent resin protective layer so as to cover the resistor layer and the marking pattern.

(2) A step of forming a resistor layer on the insulating substrate, a step of trimming the resistor layer to adjust the resistance value, and a photosensitive resin on the insulating substrate including the resistor layer. And a step of forming a protective pattern and a mark pattern for covering the trimming groove formed by the trimming by exposing and developing the photosensitive resin with a mask on which a predetermined pattern is formed, Resistor layer,
And a step of providing a transparent or semi-transparent resin protective layer so as to cover the protective pattern and the marking pattern.

[0012]

[Function] Since the marking is performed by the photolithography method,
Even with a thin line having a width of the order of 1 μm, clear notation without blurring is possible.

By adjusting the photosensitive resin to have a low viscosity, the trimming groove can be surely filled at the same time when the mark is formed.

Since the transparent or semi-transparent resin protective layer is provided, the mark does not fade or disappear, and the surface can be made smooth.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments in which the manufacturing method of the present invention is applied to a chip-shaped thick film resistor will be described with reference to the drawings, but the present invention is not limited to these embodiments. .

1 to 3 are views showing an embodiment of the present invention, FIG. 1 shows a cross-sectional view of a thick film resistor obtained by the method of the present invention, and FIG. 2 explains the method of the present invention. FIG. In these figures, reference numeral 1 denotes an insulating substrate, and 2
Is a resistor layer, 3 is a marking pattern layer, 4 is a resin protective layer, 5 is an electrode layer, and 6 is a photosensitive resin layer.

In FIG. 1, the marking pattern layer 3 is provided on the resistor layer 2. Here, the marking pattern layer 3 is provided on the resistor layer 2, but it is also possible that a part or all of the marking pattern layer 3 is provided on the insulating substrate 1. The marking layer 3 is covered with the exposed portion of the resistor layer 2 and a transparent or semitransparent resin protective layer 4.

Next, this embodiment will be described more specifically with reference to FIGS. 2 (a) to 2 (d).

As shown in FIG. 2A, a resistor layer 2 and an electrode layer 5 are provided on an insulating substrate 1, and then the resistor layer 2 is trimmed by a laser or the like to form a trimming groove 7 and a resistor. The value is adjusted.

As shown in FIG. 2B, the photosensitive resin layer 6
On the resistor layer 2 provided as described above with a film thickness of 1 to
It is provided to have a thickness of about 10 μm. The photosensitive resin layer 6 is
For example, it can be provided by applying a photosensitive resin by spin coating, roll coating, or the like, and performing temporary drying. As the photosensitive resin, in addition to known negative and positive photoresists, resins that exhibit the same action as the negative and positive photoresists in the photoresist by light (including ultraviolet rays) are limited. Can be widely used without
More specifically, a photosensitive polyimide resin or the like can be exemplified.
Further, the photosensitive resin layer 6 is preferably colored with a pigment or the like so as to have a high contrast with the underlying layer.

Next, as shown in FIG. 2 (c), the photosensitive resin layer 6 is exposed to light using a mask having a predetermined marking pattern formed thereon, and a predetermined developing solution such as an alkaline organic solvent is used. And the like, and the photosensitive resin layer 6 is removed leaving a necessary portion (marking pattern layer 3). When the marking pattern layer 3 is not sufficiently cured by the above-mentioned photosensitizing process, the mark pattern layer 3 may be irradiated with light again after the developing process to further accelerate the curing.

In this embodiment, the photosensitive resin layer 6 on the trimming groove 7 is removed, but the photosensitive resin layer 6 is left so as to fill the trimming groove 7 as shown in FIG. The protective pattern layer 3a may be formed. At this time, the photosensitive resin layer 6 is preferably adjusted to have a low viscosity and applied. By doing so, the trimming groove 7 can be covered without a gap, and when the resin protective layer 4 is provided, the trimming groove is provided. Pinholes are created from the air in 7,
There will be no gap from the trimming groove 7 to the outside air, so that the resistance layer 2 can be more reliably filled with moisture or the like.
Can be prevented from being adversely affected.

Further, in FIG. 2C, the marking pattern layer 3 is provided so as to leave the photosensitive resin layer 6 of the marking portion,
It is also possible to remove only the mark portion and leave the photosensitive resin layer 6 around it.

Then, as shown in FIG. 2D, a transparent or display color of the marking pattern layer 3 is formed by screen printing or photolithography so as to cover the exposed portions of the marking pattern layer 3 and the resistor layer 2. A semitransparent resin protective layer 4 different from the above is provided.

Although the method of the present invention has been described with reference to a thick film resistor, the method of the present invention can be applied to the manufacture of a thin film resistor.

[0026]

The manufacturing method of the present invention has the following effects.

(1) The marking can be clearly performed even with a small chip component.

(2) The mark is not blurred, blurred, or lost.

(3) The resistor layer and the mark can be protected by the same protective layer.

(4) Since the surface of the chip resistor can be made smooth and the suction property by the suction collet can be improved, reliable mounting can be performed.

(5) The trimming groove can be surely filled in the same step as the marking, and a highly reliable chip resistor can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a chip resistor obtained according to an embodiment of the present invention.

FIG. 2 is a process drawing for explaining the embodiment of the present invention.

FIG. 3 is a cross-sectional view of a chip resistor obtained according to another embodiment of the present invention.

[Explanation of symbols]

 1 Insulating Substrate 2 Resistor Layer 3 Marking Pattern Layer 3a Protective Pattern Layer 4 Resin Protective Layer 5 Electrode Layer 6 Photosensitive Resin Layer 7 Trimming Groove

Claims (2)

[Claims] 1. A marking pattern formed by applying a photosensitive resin on an insulating substrate having a resistor layer formed thereon, exposing the photosensitive resin to light with a mask having a predetermined marking pattern, and developing the photosensitive resin. And a transparent or semi-transparent resin protective layer is provided so as to cover the resistor layer and the marking pattern. 2. A step of forming a resistor layer on an insulating substrate, a step of trimming the resistor layer to adjust a resistance value, and a photosensitive resin on the insulating substrate including the resistor layer. A step of applying, a step of exposing and developing the photosensitive resin with a mask having a predetermined pattern to form a protective pattern and a mark pattern for covering a trimming groove formed by the trimming, and the resistance. And a step of providing a transparent or translucent resin protective layer so as to cover the body layer, the protective pattern and the marking pattern.