JPS599915A - Forming method for transparent-film pattern - Google Patents

Abstract

PURPOSE:To shorten processes largely while reducing cost by setting up a laser light reflecting mirror on the reverse side to the laser-light incident side of a light-transmitting substrate and cutting a transparent film by the power of incident light and reflected light when a light-transmitting film formed onto the substrate is cut by laser lights and changed into the pattern. CONSTITUTION:A transparent electrode 3 is formed onto the light-transparent substrate 2 such as glass, and laser beams 4 are irradiated to the electrode 3 to change the electrode into the pattern. The laser light reflecting mirror 1 is set up previously in parallel with the electrode 3 on the reverse side to the incident side of laser beams 4 at that time, laser beams 4 are projected rectangularly to the electrode 3, and the pattern is formed to the electrode 3 by both power of incident light and reflected light. Accordingly, the time required may be kept within one min, and washing is also simplified and waste fluid also need not be treated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of cutting a transparent film, such as a transparent film formed on a transparent substrate, with laser light to form a pattern.

Conventionally, for example, in integrated amorphous silicon solar cells,
Photo-etching is widely used to form patterns for manufacturing multiple solar cells on transparent electrodes formed on transparent substrates due to its good pattern accuracy. The process is very long,
In addition, the process of cleaning and removing the resist film and the process of cleaning and removing the etching solution consisting of acids and alkalis takes time, and if these processes are incomplete, the yield decreases, and it takes a considerable amount of time to dispose of the etching solution waste. In addition, there were other inconveniences such as the production of pinholes in the transparent electrode due to the influence of dust in the working environment and a decrease in yield.

The present invention aims to provide a method for forming a transparent film pattern using a laser beam, which can eliminate such inconveniences and shorten the pattern processing time. It is bound.

Machining using laser light is currently commonly used for trimming resistive films, but since resistive films are usually black or gray, they absorb laser light well over a wide wavelength range and can be easily separated.

However, for example, the thickness of the transparent electrode film of a solar cell (5000A
), the transmittance is high; for example, in the case of a tin oxide film, about 80% of the laser light passes through it as shown in the first figure, and it cannot be cut efficiently like a resistive film.

In order to solve this problem (when laser light is used), the present invention provides a laser light reflecting mirror on the side opposite to the laser light incident side of the transparent substrate, so that the laser incident light and the laser reflected light can be reflected. The transparent film is cut by a power of .

Now, if the cutting efficiency is A, there is a relationship as follows: ■ A = - K: Proportionality constant ■: Cutting speed (cm/sec) P: Laser power (W) According to the present invention, processing using normal laser light is possible. The cutting efficiency A can be improved by 10-50%, and the cutting speed V can be improved by 10-50% with the same laser power.
0% faster, and if the same cutting speed is sufficient, the transparent film can be cut even if the laser light power is lowered by 10 to 50%.

The laser beams used in the present invention include YAG laser (wavelength 1.06μ), ruby laser (wavelength -0, 6945μ)
or argon laser (0.5145μ or 0.4880μ
), 00 laser (10μ), etc. can be used.

Example 1 A 13 cm thick tin oxide film with a film thickness of 500X was deposited on one surface.
Two square glass plates were prepared, and a pattern of transparent conductive film for manufacturing 16 calculator batteries (5-element series type) was formed thereon using a YAG laser. As shown in the second figure, a laser beam reflecting mirror (1) is arranged parallel to a transparent electrode (3) on the side opposite to the laser beam incident side of a transparent substrate (2), and the laser beam ( 4) was incident on the transparent electrode (3) at right angles to cut it. The remaining one is a transparent substrate (2) as shown in the third figure for comparison with the present invention.
A laser beam (4) was incident on the transparent electrode (3) in a direction perpendicular to the transparent electrode (3) to cut it.

The laser power for both was IW and the laser beam diameter was 25 μm. The maximum cutting speed in this case is 15 cm/se
c, and when no reflector is used, 100m/SeC
Therefore, the cutting speed could be increased by 1.5 times using the same laser beam. Therefore, the processing time for a 16 cm square substrate was approximately 40 seconds, which was significantly shorter than the approximately 1 minute required without a reflecting mirror.

Example 2 Cutting power was measured under the same conditions as in Example 1.

The cutting speed of the method according to the present invention and the method not using a reflecting mirror was constant at 10 r, m/Sec, and the laser beam diameter was 25 μm.

The cutting power of the present invention at this time is 0.7W, which is at least 1
Compared to a method that does not use a reflecting mirror that requires W, it can be made smaller, and the cost can therefore be reduced by about 30%.

In this way, according to the present invention, a laser beam reflecting mirror is disposed on the side opposite to the laser beam incident side of the transparent substrate, and the laser beam is made incident on the transparent film on the transparent substrate, and the incident light and Since the transparent film was cut by the power of the reflected light,
Compared to the conventional pattern forming method using photoetching, the process can be significantly shortened and costs can be reduced, the cleaning process is simple, there is no need for waste liquid treatment, and there is no need to use reflected laser light. It has the effect of being able to process with lower power and faster cutting speed.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the transmittance characteristics of glass and transparent electrodes with respect to the wavelength of light, FIG. 2 is a detailed explanatory diagram of the present invention, and FIG. 3 is an explanatory diagram of a knot-turn forming method that does not utilize reflected light. tl)...Laser light reflecting mirror (2)...Transparent substrate (3)...Transparent electrode (4)...2 people outside the laser beam

Claims (1)

[Claims] In a method of forming a pattern by cutting a transparent film formed on a transparent substrate with a laser beam, a laser beam reflecting mirror is disposed on the side opposite to the laser beam incident side of the transparent substrate, and the laser beam is and a transparent film pattern forming method, characterized in that the transparent film is cut by the power of laser reflected light.