JPS61111791A - Manufacture of amorphous silicon semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the generation of a flaw and to execute cutting at a high speed by forming an amorphous silicon thin film on a flexible substrate, and subsequently, cutting it to an optional size by a laser beam. CONSTITUTION:An (a)-Si tape 1 which forms an amorphous silicon thin film on a plastic flexible substrate is wound to a roller 2. The end of the tape 1 is fed out and its initial end 4 is pinched by fixing materials 3. Subsequently, an irradiating nozzle 5 of a laser beam is provided on the upper part of the tape 1, and moved in the horizontal direction by irradiating a laser beam 6 onto the tape 1. In this case, the cut line 7 of cutting is formed on the (a)-Si tape 1. By irradiating the laser beam 6, a large quantity of heat are generated locally, therefore, the (a)-Si tape 1 is cut instantaneously. Accordingly, a smooth cutting plane having no flaw is formed, and also the cutting can be executed at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION (7') Technical Field The present invention relates to a method of manufacturing an amorphous silicon semiconductor device.

Electrophotographic photoreceptors include inorganic photoreceptors and organic photoreceptors.

Inorganic photoreceptors include Ss, CdS, and Zn.
O1Ss-To, l5e-As, -7motrefussy
There are examples such as s:I-n (abbreviated as a-3i). these are,
It is an amorphous material that utilizes the photoconductive effect.

Examples of organic photoreceptors include PVK, pyrazoline, perylene, and phthalocyanine.

Inorganic 7Mo/L'fas materials such as Ss1Se-Te, 5e-As, and CdS are already widely used as electrophotographic photoreceptors and have a proven track record. However, these
Both are highly toxic. It is not possible to arbitrarily incinerate used photoreceptors.

Ss, CdS has previously been used in the form of a drum-wound material. This is because these do not have sufficient surface hardness. However, the drum-shaped electrophotographic photoreceptor is
There was little freedom in mechanical design and it was inconvenient to handle. Since it has to be in the form of a rigid drum, the cost is relatively high.

Among these, amorphous silicon has excellent features such as being non-toxic, having strong surface strength, and high sensitivity. It is expected that its use will increase more and more in the future.

Since amorphous silicon has strong surface strength, it is not necessarily necessary to form a film on the drum.

Amorphous silicon can be formed into a film on a flexible substrate.

Since the film can be formed on a flexible substrate, the degree of freedom in design is greater than in the case of a drum.

Maintenance becomes easier and costs can be reduced.

It is also easy to replace just the photoresist film.

Silicon is non-toxic, and used photoresists can be disposed of by incineration.

As described above, there are strong expectations for electrophotographic photoreceptors in which amorphous silicon is formed on a flexible substrate.

The device described above is one of the amorphous silicon devices that utilize photoconductive effects.

Amorphous silicon has a photoconductive effect fl! Plus, it has photovoltaic effects, thermoelectric effects, piezoelectric effects, and many other physical and industrial features. For this reason, amorphous silicon is beginning to be applied to various devices.

Octopus Conventional technology One of the outstanding features of amorphous silicon thin film is that
This means that it is possible to continuously deposit a wide thin film at a very fast speed.

The plastic substrates wound around a roll are unrolled one after another, and a thin film of 7-E/L'777 and SiJJ (a-3i) is formed on the substrates by, for example, plasma CVD (plasma chemical vapor deposition) method. I will do it.

The substrate material is flexible and in the form of a long tape. Since this is fed at a constant speed and a thin film is formed at a constant speed, an a-Si film with a uniform thickness can be obtained. The film that has been formed is sequentially wound up by a winding device. In this way, a photoreceptor having an a-3i film formed on the substrate is continuously produced in the form of a tape and held in the form of a roll.

Since it is a continuous photoreceptor material, the substrate must be cut to an appropriate length when used as an electrophotographic photoreceptor or other device.

Here, a continuum in which an a-3i film is formed on a substrate is
We will call it a-Si tape. To make a device, the continuous body is cut, and the cut pieces are called a-Si sheets.

Conventionally, a-Si tape has been cut using a cutter, knife, cutter, or the like. Often cut at right angles to the longitudinal direction.

If a-3i sheets cut in this way are repeatedly used for electrophotography, for example, the photosensitivity will deteriorate unexpectedly quickly.
There is a thing.

With repeated use, the quality of the copied images deteriorates rapidly.

It turned out that the cause of this was a scratch on the cut part. When a-3i tape is mechanically cut with a cutter or the like, countless minute scratches occur along the cutting line. There are many minute scratches, even if they are not visible to the naked eye.

The a-Si sheet is repeatedly wound around the roller or rewound. With repeated use, strong tensile stress appears and disappears in the a-3i film.

As compressive stress and tensile stress act repeatedly, minute scratches along the cutting line become seeds that gradually become larger racks, and macroscopic racks grow up to the center of the a-3i sheet. Since scratches and cracks increase in number in a dendritic manner and grow, when used as a photosensitive material, the photosensitive properties deteriorate.

Even though the a-3i film has excellent surface hardness, is it still sensitive to scratches? The reason for this can be considered as follows.

Amorphous silicon has large distortion B'A wor%
It is made on a board and is attached to the substrate while exerting internal stress on each other. It is a highly rigid membrane. It has almost no elasticity. The substrate is a flexible pouch tape. The coefficient of thermal expansion is also different.

a-3i mechanically with a cutter, knife, cutting machine, etc.
When the tape is cut, since the a-Si film has high rigidity, many minute scratches are generated near the cut portion. Stress is released at the scratched area, and the a-8i film contracts or expands. A-5i also expands and contracts at the scratched portion of the substrate due to temperature changes.

Furthermore, since the a-3i sheet is used by being repeatedly wound up and unwound on a roller, the stress also changes.

For this reason, once a small scratch occurs, it becomes a seed and a large crack develops.

Macroscopic defects include not only cracks but also peeling of the a-3i film from the edges. This is called peeling.

(T) Purpose Forming an amorphous silicon film L7M! It is an object of the present invention to prevent small scratches from occurring at the cut portion when cutting the i-board to a desired length. Since no cracks occur, the characteristics do not deteriorate even if used repeatedly as an a-3i semiconductor device.

B) Method of the Invention In the present invention, the a-Si tape is cut by irradiating it with laser light instead of mechanical cutting.

FIG. 1 is a perspective view showing how the a-3i tape 1 is cut with a laser beam.

An a-Si tape 1 is wound around a roller 2. This is a plastic J1 (with an a-3i thin film formed on the -1- of the plate), and the manufacturing method is well known.

In addition to the previously mentioned plasma CVD, silane SiH is produced using light.
4 Complete decomposition 't light CVD, thermal decomposition of SiH4-
j le CVD.

A-Si tapes can be made by reactive ion blasting, reactive vapor deposition, reactive sputtering, and the like.

a-3i Pay out the end of the tape 1 and attach the starting end 4 to the fixing member 3
Sandwich with.

A laser beam irradiation nozzle 5 is provided above the a-3i tape 1. From here, the laser beam 6 is irradiated onto the - side of the a-3i tape 1.

The laser beam 6 is made to move laterally on the a-3i tape 1. The a-3i tape 1 is cut by the laser beam 6. The cut lower runs on tape 1.

The laser +f is preferably a tV laser, a glass laser, a YAG laser, a CO□ laser, or the like. Laser output is several tens of W
~Hundreds of units are required.

The laser beam 6 must move on the tape 1,
The stiffness can be avoided by moving the tape 1 in parallel, or by moving the laser beam 6 in parallel.

The laser beam is directly emitted from the laser body and
You can apply it to the tape, or if you can use an infrared lens, you can use it to focus it.

If an optical fiber can transmit light of that wavelength with low loss, the laser main body and the laser beam irradiation nozzle 5 can be completely separated, and the two can be connected by the optical fiber.

Since there is no suitable optical fiber for a device such as a carbon dioxide laser that generates far-infrared light in a large output direction, the laser beam 6 can be moved by combining mirrors and rotating the mirrors.

When the laser beam is irradiated, a large amount of heat is locally generated in the irradiated area, and the a-3i film and substrate are melted and evaporated, so that the a-3i tape is instantly cut.

The fixing member 3 consists of an upper plate 9 and a lower plate 10, which sandwich the starting end 4. For example, the following mechanism can be considered as a mechanism for moving the starting end of the a-3i tape 1 from point B to point A. It will be done.

One is to provide a tape feeding device (not shown) that reciprocates between AB, which grips the tape starting end 4 and
-3i Tape 1 is fed out and pulled from position B to position A,
Place the starting end 4 on top of the fixing member 3. Next, the -1- plate 9 of the fixing member 3 descends to sandwich the starting end 4 together with the lower plate 10.

The other is to allow the fixing member 3 to reciprocate between AB. When the tape 1 is cut at the cut 7, the upper plate 9 rises and drops the sheet, and the upper and lower plates 9.10
moves forward and comes to position B.

After this, the engine moves back to position A after starting 4.

Then, the tape is cut using a laser beam.

There may be various other movements and functions of the fixing member 3.

The distance between AB is the length of the cut sheet.

) effect (1) Thermal cutting by laser beam irradiation.

A-3T tape is cut by melting and evaporating it. Furthermore, there is no need for any object to come into contact with the material; it is completely non-contact cutting.

Compared to using a tool, processing distortion is smaller, so a smooth cut surface without scratches can be obtained.

When cutting with a cutter, many scratches occur because the A-3I film is in a highly rigid state. Since the laser beam heats and melts the a-3i film, it has low rigidity and is in a flexible state.

Therefore, scratches are less likely to occur.

(2) It can cut at high speed. For example, several m/mi
It is easy to cut at a speed of n.

(If the thickness of the aha-st film is large, cutting with a cutter, knife, etc. will particularly damage the cut part and cause many scratches, but the present invention can You can learn how to cut without creating any scratches.The present invention is particularly effective when the film thickness is 1 μm or more.

Trout) Experimental Example The same test was conducted on a-3i sheets cut by the conventional cutting method and the cutting method of the present invention, and an experiment was conducted to compare the occurrence of cracks.

a-Si tape (width 8QcIn) made by a known method
was cut into a length of 60ffi using a cutter.

A 30 m x 60 m a-Si sheet was wound between two rollers 20, 21 with a diameter of 50 mm, as shown in FIG. Of course, both ends of the sheet are glued together to form an endless belt. Tension is applied to the roller 21 by a spring 23. The magnitude of the tension is 50 kQ. Then rotate the roller.

This test examines whether cracks occur and grow by frequently changing the curvature of the a-Si sheet. When in contact with the roller, the radius of curvature is 50 mm, but as it moves away from the roller, the radius of curvature increases to infinity.

The a-Si sheet cut by the cutter has approximately 100
It was found that after 0 rotations, a crack was generated and growing from the end in a direction perpendicular to the direction of travel. For example, when used as a photoreceptor for electrophotography, it can no longer be used as a photosensitive film.

A-3i tape made in the same way, output 100W
CO. Cutting was performed using a laser at a speed of 2 m/rrLin.

A sheet of 801 m x 60 ff is obtained. Glue both ends in the same way to make an endless belt. The same tension is applied to the test apparatus of FIG. 2, and the roller is rotated.

Even after 100,000 rotation tests, no scratches or cracks were observed. The properties as a photoreceptor for electrophotography were also good.

(Uses) The present invention can be widely used for manufacturing amorphous silicon semiconductor devices.

(1) Amorphous silicon photoreceptor (2) Amorphous silicon thick Flljt 71b (i31) Amorphous silicon image sensor (4) Other amorphous silicon applied devices

[Brief explanation of the drawing]

FIG. 1 shows the a-9i semiconductor device of the present invention! li',
! FIG. 3 is a schematic perspective view showing method a. FIG. 2 is a schematic diagram showing a testing apparatus for a-3i sheets. 1... a-9i tape 2... Roller 3...
...Fixing member 4 ...Tape starting end 5 ...Laser light irradiation nozzle 6 ...
・Laser beam 7... Cutoff date 9...Top plate 10...Bottom plate

Claims (3)

[Claims] (1) An amorphous silicon semiconductor device in which an amorphous silicon tape, which is an amorphous silicon thin film formed on a flexible substrate, is cut into a desired size by irradiating it with laser light to produce an amorphous silicon semiconductor device. Method of manufacturing the device. (2) The method for manufacturing an amorphous silicon semiconductor device according to claim (1), wherein the amorphous silicon semiconductor device is an amorphous silicon photoreceptor. (3) The method for manufacturing an amorphous silicon semiconductor device according to claim (1) or (2), wherein the amorphous silicon layer of the amorphous silicon semiconductor device has a thickness of 1 μm or more.