JPH04142037A - Correction method of chipped-off part at conductor - Google Patents

Abstract

PURPOSE:To enhance a conductive property between conductors and to enhance a close contact property between a conductor for correction and a substrate by a method wherein the conductor for correction and an existing conductor as a film on the substrate are irradiated with a laser and they are melted in a short time and partially. CONSTITUTION:A substrate 10 where a chipped-off part 14 is caused at an Al conductor 12 formed as a film is coated with a photoresist 16; the substrate 10 is exposed to light and developed; an opening part is formed; the chipped-off part 14 is revealed. Then, an Al conductor 18 for correction is formed as a film on the revealed chipped-off part 14. The Al conductor 18 for correction use and the existing Al conductor 12 as the film on the substrate are irradiated with a laser and melted. After that, the inessential conductor for correction and the photoresist are removed. Thereby, an oxide film between the Al conductor 18 for correction and the Al conductor 12 is eliminated, and a good continuity state and a good contact force are obtained. Also a discontinuous face at a microslit is melted. As a result, the discontious Al conductor is obtained, and a close contact property with a substratum at the chipped-off part 14 not provided with the Al conductor 12 is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for repairing a defective portion of a conductor, and more particularly to a method for repairing a defective portion of a conductor, and particularly to a method for repairing a defective portion of a conductor, which has excellent conductivity between a conductor for repair and a conductor formed on an existing substrate.

[Prior Art] Conventionally, there has been a manufacturing method in which a circuit consisting of a thin film resistor, an A1 conductor, a protective film (oxidation resistant film, abrasion resistant film), etc. is formed on a large substrate to create, for example, a thermal head. Are known. In such a manufacturing method, defects in the circuit are unavoidable, and corrections are often required.

FIG. 3 is a process diagram showing a conventional method for correcting conductor defects.

FIG. 3(a) shows a cross-sectional view of the thermal head, with the substrate 1
Thin film resistor or AI on 0! A conductor such as a conductor, in this case an A1 conductor 12, is formed in a film pattern. AI!
The conductor 12 has a defect 14 as shown in the figure.

The repair process begins by coating the entire surface of the substrate with a photoresist 16, as shown in FIG. 3(b). Next, as shown in FIG. 3(C), exposure and development is performed to provide an opening in the photoresist 16 and expose the defective part 14. Subsequently, as shown in FIG. 3(d), a repair A1 conductor 18 is formed over the entire surface of the substrate. Then, the repairing Af conductor 18 on the photoresist 16 other than the defective portion 14 is peeled off (see FIG. 3(e)), and the photoresist 16 is also peeled off (see FIG. 3(f)). In this way, A1 conductor 1
2 deficiencies were corrected.

[Problem to be solved by the invention] However, according to the conventional method for repairing conductor defects,
There were some drawbacks as follows.

■Since an oxide film is naturally formed on the surface of the Af conductor 12 on the existing substrate after film formation, the A conductor 12 and the repair A, 12
The conductivity with the conductor 18 becomes poor, resulting in high lead resistance.

(2) The repairing Al conductor 18 has a limited upper limit of film forming temperature due to the characteristics of the photoresist 16, so it has poor adhesion to the substrate 10 or A) conductor 12 and is likely to peel off.

■A,! ! At the end of the conductor 12, the film of the repairing A1 conductor 18 does not wrap around well, and the AI conductor 12 and the repairing A1 conductor 1
A gap (micro slit) is generated between the conductors and the conductor, resulting in poor conductivity between the conductors.

The present invention has been made to solve the above problems, and its purpose is to provide a method for repairing a defective conductor portion with excellent conductivity, adhesion, and repairability.

[Means for Solving the Problems] In order to achieve the above object, a method for repairing a conductor defect according to the present invention includes a step of applying a photoresist on a substrate in which a defect occurs in a formed conductor; The steps include an exposure phenomenon step in which an opening is formed in the photoresist and a defective portion is exposed by performing an exposure phenomenon on the substrate, and a repair step in which a repair conductor is formed as a film on the exposed defective portion. In a method for repairing a defective part of a conductor that has been formed into a film, the repairing conductor and the existing film-formed conductor on the substrate are melted by laser irradiation, and after melting, the unnecessary repairing conductor is removed. and a removing step of removing the photoresist.

[Function] In the method for repairing a conductor defect of the present invention having the above-mentioned configuration, the repair conductor and the existing film-formed conductor on the substrate are melted briefly and partially by laser irradiation, thereby reducing the gap between the conductors. It has excellent conductivity and can improve the adhesion between the correction conductor and the substrate.

[Example] Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a process diagram showing an embodiment of a method for repairing a conductor defect according to the present invention. Note that the same parts as in FIG. 3 are given the same reference numerals.

First, as shown in Figure 1(a), a resistor, A1 conductor 1
After forming the second layer and forming the pattern, electrical properties (conductivity)
is measured, and the substrate 10 in which the conductor defective portion 14 has occurred is detected.

Next, as shown in FIG. 1(b), for example, a positive photoresist 16 is applied to the entire surface of the substrate 10.

Subsequently, as shown in FIG. 1(c), by exposing and developing the defective portion 14, A! The missing portion of the conductor 12 is exposed. At this time, the ends of the A conductor 12 to be connected are exposed on both sides by modification.

Next, as shown in FIG. 1(d), the exposed defect 1
A repair A1 conductor 18 is formed on the substrate including A1.

Subsequently, as shown in FIG. 1(e), the repair A, 12 conductor 18 and the A conductor 12 formed on the existing substrate are melted by laser irradiation. FIG. 2 is a plan view of the substrate showing the laser irradiated portion. As shown by diagonal lines in the figure, the laser irradiation portion 20 is formed by, for example, a slit with a spot diameter of 10 to 2 mm.
The width of the conductor 12 is approximately 1/3 of the width of the A1 conductor 12. By this laser irradiation, the portion where the repair A, 4 conductor 18 and the A1 conductor 12 overlap in two layers, the end of the A1 conductor 12 where micro-slits are likely to occur, and the repair AI conductor 18 that is in contact with the substrate 10. or it will definitely be melted.

For this reason, the correction A1 conductor 18 and the AJ! There is no oxide film between the layers of the conductor 12, resulting in good conduction and adhesion. Furthermore, since the discontinuous surfaces of the microslits are also melted, continuous A and f77 layers can be obtained. moreover,
Adhesion is also improved to the base of the defective portion 14 where the A conductor 12 was not present.

Note that the laser irradiation time is about μsec, and the power is set to such an extent that the A1 conductor is melted and not all of it is scattered.

Next, the excess correction A1 conductor 18 shown in FIG. 1(e) is removed using, for example, a peeling adhesive tape. Then, the photoresist 16 is removed using a stripping solution.

Note that the extra conductor for correction serves as a masking material for metal vapor during laser irradiation. In addition, since the A1 conductor 18 for repairing the defective part 14 is melted and in close contact with the base,
It will not peel off at the same time as the extra repair AI conductor.

Furthermore, depending on the laser irradiation conditions, it is also possible to cut off the excess A1 conductor for correction.

By the laser irradiation, the repairing A1 conductor 18 is melted and reliably connected to the A1 conductor 12, and a good electrical conduction state is obtained with respect to the AI conductor 12 which has no defects. Therefore, by monitoring the irradiation state during laser irradiation, it is possible to determine whether conduction is possible or not based on the appearance. From this, it is not necessary to check by the resistance value (conductivity) whether the correction has been made or not, and it can be passed on to the subsequent process as is.

The repair method of the present invention as described above is particularly effective for repairing circuit defects when manufacturing a thermal head, for example.

In the thermal head, it is preferable that, for example, the AJ conductor connected to the heating element has a low resistance value and a small drag. The resistance value change of this conductor, the resistance value characteristic of the thermal head,
In other words, it affects printing quality. Therefore, when high-quality printing is aimed at with a thermal head, it is natural that the variation in resistance value of the thermal head should be minimized to improve printing quality. Such variations in conductor resistance values can be reduced by using the modification method of the present invention, and the present invention is particularly effective in modifying circuits in which it is desired to reduce variations in resistance values.

In addition, in the embodiments described above, the case where the repair conductor is made of the same material as the existing film-formed conductor on the substrate (A, 12 in the embodiments) is illustrated, but the present invention is limited to the above embodiments. Instead, a correction conductor made of a different material may be used.

[Effects of the Invention] As explained above, according to the method for repairing a conductor defect according to the present invention, the conductor film formed on the substrate and the conductor for repair are melted by a laser to form a continuous conductor. Reliability equivalent to non-conductor conductors can be obtained, and lead resistance is also reduced.
An equivalent value can be obtained.

Furthermore, since laser treatment is performed before removing the excess correction conductor, there is no contamination by hot steam and no reduction in the adhesion of the protective film or the like.

Furthermore, since a reliable fusion connection can be made between the conductors, there is no need to check the surface oxidation state of the conductor or remove the oxide film before repair, and the film formation conditions for the repair conductor can be maintained to a certain degree with adhesion. The better, the film forming conditions will be simpler.

In addition, since defective conductors are reliably identified as non-defective products, repeated repairs and disposal are eliminated, improving repair efficiency.

[Brief explanation of the drawing]

FIGS. 1(a) to (f) are process diagrams showing one embodiment of the method for repairing conductor defects according to the present invention, FIG. 2 is a plan view of the substrate showing laser irradiation time, and FIG. 3(a) -(f) are process diagrams showing a conventional method for correcting conductor defects. Board AJ! A, +2 conductor laser irradiation area for photoresist repair of conductor defects

Claims (3)

[Claims] (1) A process of applying a photoresist onto a substrate in which a defect has occurred in the conductor that has been formed, and an exposure phenomenon process of exposing the defect by creating an opening in the photoresist by performing an exposure phenomenon on this substrate. and a repair process of depositing a repair conductor on the exposed defective part.
A method for repairing a defective part of a conductor formed on a substrate, comprising: a melting step of melting the repair conductor and the existing film-formed conductor on the substrate by laser irradiation; and after melting. A method for repairing a defective conductor, the method comprising: a removing step of removing an unnecessary repair conductor and photoresist. (2) A method for repairing a defective conductor portion according to claim (1), wherein the repair conductor and the existing film-formed conductor on the substrate are made of the same material. (3) A method for repairing a defective conductor portion according to claim (1), wherein the repair conductor and the existing film-formed conductor on the substrate are made of different materials.