JPH04249312A - Proximity irradiation apparatus - Google Patents

Abstract

PURPOSE:To easily position and convey a substrate and to make the title apparatus compact by eliminating a need for a chamber for inert-gas filling use. CONSTITUTION:Many gas blowoff holes 7 are made in a stand 1 and an inert gas G is jetted from the gas blowoff holes 7 toward a large-sized mask 3. Thereby, the large-sized mask 3 is levitated from a substrate 2. The gas-blowoff holes 7 are tilted to the direction of a stopper 4 installed on the mounting face 1a of the stand 1. The large-sized mask 3 is pressed to the stopper 4 by the stream of the gas G and is positioned.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a proximity irradiation device used in optical processing of semiconductors.

0002

[Prior Art] In recent years, microfabrication processes using light energy have been put into practical use as semiconductor processing processes.
In particular, since excimer lasers were commercialized in the 1980s, laser processes that apply photochemical effects have been attracting attention. This laser process makes it possible to manufacture thin film semiconductors at a low temperature of 250° C. or lower, so it is possible to manufacture active matrix large-screen liquid crystal display devices using, for example, inexpensive substrates with low heat resistance. As an apparatus for performing such a laser process, for example, as shown in FIG. 4, an apparatus using a so-called proximity method is known, in which a laser beam L is irradiated with a large mask 20 in close proximity to a substrate 21. ing. In this apparatus, a large mask 2 is placed in a large chamber 22 in order to maintain a vacuum atmosphere near the substrate 21 or to fill an inert gas to prevent reaction with the atmosphere.
Further, a laser beam L is irradiated from a laser light source 24 to the substrate 21 through a transparent member 23 at the top of the chamber 22.

0003

However, in such a conventional example, since the large mask 20 and the substrate 21 are arranged in a sealable chamber, it is troublesome to position the mask 20. However, there has been a problem in that it is not possible to easily transport the material to the next process, and therefore it is not possible to improve the efficiency of the TFT (thin film transistor) manufacturing process. Furthermore, in the conventional example, as the substrate 21 becomes larger, the chamber 22 also becomes larger, so there is a problem that the device also becomes larger. By the way, the above-mentioned laser process involves a process (e.g. CVD, impurity doping, etc.) in which a vacuum atmosphere is created and then a necessary gas is introduced to irradiate the pattern (for example, CVD, doping with impurities, etc.), and creating a vacuum is not a necessary condition.
Processes that require pattern irradiation while preventing reactions with the atmosphere using inert gas, etc. (annealing, ablation, etc.)
There is. Therefore, in the latter process such as annealing, the chamber 22 is not necessarily required. In addition to the proximity method described above, a projection method is also known as a pattern irradiation method, in which the image of the mask is reduced and projected using a lens. The proximity method has better pattern matching accuracy and work efficiency.

[0004] The present invention has been made in view of the above-mentioned problems of the prior art, and its purpose is to facilitate the positioning and transportation of substrates by eliminating the need for a chamber for filling with inert gas. The object of the present invention is to provide a proximity irradiation device that can achieve compactness of the device.

[0005]

[Means for Solving the Problems] The present invention, as shown in FIG. In the proximity irradiation device that processes the substrate by irradiating the substrate surface with the inert gas G from the injection nozzle 7 directed from the substrate support 1 side toward the optical mask plate 3 side, The plate 3 is made to float above the substrate surface.

[0006]

[Operation] In the present invention having such a configuration, the inert gas G is jetted from the jet nozzle 7 directed from the substrate support stand 1 side toward the optical mask plate 3 side, so that the optical mask plate 3 can be attached to the substrate 2. Since it is made to float above the substrate surface, the inert gas G is always present between the substrate surface and the optical mask plate 3, and the thin film formed on the substrate surface is prevented from reacting with the atmosphere. Therefore, according to the present invention, there is no need for a chamber to be filled with gas in a process that does not require a vacuum atmosphere.

[0007]

Embodiments Hereinafter, embodiments of the proximity irradiation apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 shows the overall configuration of this embodiment. As shown in the figure, a flat base 1 is constituted by a placing part 1a and an air pocket forming plate 1b, and this placing part 1
The substrate 2 is placed approximately in the center of the area a. Then, the large mask 3 is floated above the substrate 2 by means to be described later, and its position is determined by a stopper 4 provided on the mounting portion 1a.

Furthermore, a laser light source 5 is arranged above the large mask 3, and a laser beam L is irradiated onto the substrate 2 through the large mask 3. In this case, the laser to be irradiated is an excimer laser (XeCl wavelength=308
nm). This is because the excimer laser can stably irradiate for a long time and is suitable for annealing thin silicon films. The large mask 3 is a quartz glass substrate 3a coated with a chromium film to form a predetermined pattern 3b.

The substrate 2 used in this embodiment is made of glass material and has a square shape with one side of 250 mm. That is, this substrate 2 is used as a TFT active matrix substrate for a liquid crystal large screen display device. Then, on the surface of the substrate 2, plasma C
An amorphous silicon film having a thickness of 0.6 to 0.8 μm is formed by VD.

The substrate 2 is placed on the mounting section 1a of the base 1 as described above, but the substrate 2 is placed on the top surface of the mounting section 1a.
In order to position and fix the substrate 2, a plurality of positioning pins 6 are embedded to match the size of the substrate 2.

A large number of gas ejection holes 7 are provided on the upper surface of the mounting portion 1a of the base 1. These gas ejection holes 7 are arranged so as to surround the substrate 2 on the mounting section 1a, as shown in FIG. 2, and in addition, as shown in FIG.
In order to inject the gas G toward a wall-shaped stopper 4 provided perpendicularly to one edge of a, the stopper 4 is formed to be slightly inclined from the vertical direction toward the stopper 4 .

On the other hand, a recessed portion is formed in the lower part of the mounting portion 1a so as to surround the substrate 2, and is connected to the above-mentioned gas ejection hole 7. Therefore, the air pocket 8 is formed within the base 1 by attaching the above-mentioned air pocket forming plate 1b to the lower part of the mounting portion 1a. Furthermore, this air pocket 8 is connected to a gas supply source (not shown) via a gas inflow joint 9 and an inflow pipe 10 provided on the lower surface of the air pocket forming plate 1b. In addition, the gas G used in this example
is nitrogen (N2), argon (Ar), helium (H
e) Inert gas such as

Next, a method of using this embodiment will be described below. First, the substrate 2 on which a pattern is to be formed is fixed at a predetermined position on the mounting portion 1a of the base 1, and the large mask 3 is placed on top of it. Next, gas G is supplied from a gas supply source (not shown),
Gas G is ejected from the gas ejection hole 7 via the gas inflow pipe 10 and the air pocket 8. Then, the large mask 3 floats up from the substrate 2 due to this gas injection, and a gap is created between the large mask 3 and the mounting portion 1a. Note that the substrate 2 may be fixed after the large mask 3 is floated by gas injection. This improves the efficiency of continuous work. In this case, since the gas ejection hole 7 is formed to be inclined toward the stopper 4 as described above, the gas G also flows toward the stopper 4, so that the large mask 3 abuts against the stopper 4. Therefore, in this embodiment, the large mask 3 can be positioned simply by ejecting the gas G. Note that the gap between the large mask 3 and the substrate 2 is 0.1~
The ejection speed of the gas G is adjusted in advance according to the type of the large mask 3 so that the ejection speed is about 0.3 mm. Incidentally, in this example, the flow rate is 20 ml/min.

Furthermore, a laser beam L is emitted from the laser light source 5.
The laser beam L is scanned and emitted, and the substrate 2 is irradiated with a pattern of the laser beam L through the large mask 3. Thereby, the amorphous silicon film on the substrate 2 is annealed and crystallized according to a predetermined pattern. In this case, since the inert gas G is always present between the substrate 2 and the large mask 3,
The amorphous silicon film on the substrate 2 is prevented from reacting with the atmosphere. Incidentally, annealing and crystallization of the amorphous silicon film are performed on a portion several hundred angstroms from the surface thereof.

As described above, according to this embodiment, since the conventionally used chamber is not required, the substrate 2
It is possible to easily position the parts and transport them when moving on to the next process, thereby improving work efficiency. Furthermore, since a large chamber is not required, there is also the effect that the apparatus can be configured compactly.

In the above embodiment, the surface of the substrate 2 is irradiated with the laser beam L to anneal the amorphous silicon film.
Although the process of crystallization has been described as an example, the present invention is not limited to this, and includes, for example, a dry etching method that uses laser beam energy to cleave molecular bonds and perform high-precision removal processing at low temperatures. It can also be applied to processes that do not require a vacuum atmosphere, such as ablation processes.

Further, in the above-mentioned embodiment, the gas jet hole 7 is tilted in the direction of the stopper 4, and the large mask 3 is positioned by abutting against the stopper 4 using the gas flow. The invention is not limited to this, but for example, as shown in FIG. 3, by forming all the gas ejection holes 7A toward the center of the substrate 2 and tilting the entire device so that the stopper 4 is at the bottom, a large mask 3 can be formed. A configuration in which it abuts against the stopper 4 may also be adopted.

Further, the positions and number of gas ejection holes 7, 7A can be arbitrarily selected as long as the large mask 3 is reliably positioned against the stopper.

[0020]

[Effects of the Invention] As described above, in the present invention, the optical mask plate is floated above the substrate surface by injecting inert gas from the injection nozzle directed from the substrate support side toward the optical mask plate side. This eliminates the need for a chamber filled with gas in processes that do not require a vacuum atmosphere. Therefore, the substrate can be easily positioned and transported when moving to the next process, and the efficiency of the TFT manufacturing process can be improved. Furthermore, since a large chamber is not required, there is also the effect that the apparatus can be made more compact.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional view showing the overall configuration of an embodiment of a proximity irradiation device according to the present invention.

FIG. 2 is a perspective view of a base for showing gas ejection holes of the same embodiment.

FIG. 3 is a partial vertical cross-sectional view showing the main part configuration of another embodiment of the present invention.

FIG. 4 is a schematic configuration diagram showing a conventional proximity irradiation device.

[Explanation of symbols]

1 Base 1a Placement section 2 Board 3. Large mask 4 Stopper 7 Gas blowout hole L Laser beam

Claims (1)

[Claims] 1. A proximity irradiation device that processes a substrate by irradiating the surface of the substrate with a light beam through an optical mask plate disposed close to the surface of the substrate installed on a substrate support, comprising: A proximity irradiation device characterized in that the optical mask plate is made to float above the substrate surface by injecting inert gas from an injection nozzle directed from the substrate support side toward the optical mask plate side.