JPS61128518A - Production equipment for semiconductor - Google Patents

Abstract

PURPOSE:To improve the uniformity of film thickness, to inhibit the concentration and pressure change of a reaction gas and to manufacture a semiconductor having high performance efficiently at low cost by moving a substrate while closing a clearance formed between a table and the inner wall surface of a reaction chamber. CONSTITUTION:A moving table 19 is rocked and moved in the direction that reaction gases flow, and all of each section of the surface of a substrate 5 in the direction are exposed to the reaction gases having several concentration at respective position in said direction at every same time. Consequently, even when concentration distribution in the direction that the reactions gased flow is made unequal by the change of the concentration of the reaction gases due to the diffusion and the disturbance of flow of the reaction gases, a thin-film having uniform film thickness is formed. A clearance is shaped between the table 19 and the inner wall surface 1b of a reaction chamber with the movement of the table 19, but the clearance is closed by a peripheral closing member 25, and a reaction gas 4 hardly flows to the lower section 1a of the reaction chamber.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a method of projecting light onto a reaction gas to cause a photochemical reaction and forming a thin film on a substrate placed in the reaction gas.
The present invention relates to a semiconductor manufacturing apparatus that forms a thin film using a photo-excited CVD method (hereinafter referred to as photo-excited CVD method).

[Conventional technology]

The CVD method is an important technology for forming thin films in integrated circuit devices, but in the conventional CVD method, the reaction gas is mainly heated to cause a chemical reaction, which results in a high reaction temperature. The thin film formed by this method is easily damaged.

Therefore, recently, a photo-excited CVD method has been attracting attention as a low-temperature CVD technique. This photo-excited CVD method uses light as an energy source for CVD. According to this method, the reaction temperature can be lowered compared to conventional thermally-excited CVD methods, plasma CVD methods, etc., and there is no damage to thin films. little (can be)

Furthermore, it is generally known that in the photo-excited CVD method, the concentration of the reactant gas and the illuminance of light have a large effect on the thin film formation rate.

Figure 2 shows the basic configuration of a conventional thin film forming apparatus using such a photo-excited CVD method, and Figure 3 shows the configuration of ■-■ in Figure 2.
A line cross-sectional view is shown.

In both figures, 1 is a reaction chamber in which the pressure is reduced to a high vacuum during film formation, 2 is a light source consisting of a linear lamp, 3 is a heater for heating the substrate, 4 is a reaction gas, 5 is a substrate, and 6 is a light source. A light entrance window made of a transparent material, 7 a reaction gas supply port, 8 a gas discharge port for discharging the gas 4a after the reaction, and 9 a table on which the substrate 5 is placed.

In this conventional device, the reaction gas 4 is supplied from the supply lower to the reaction chamber 1.
When introduced into the reactor gas 4, the reaction gas 4 is excited and decomposed by the light beam projected from the entrance window 6. The resulting reaction products are deposited on the substrate 5 heated at a low temperature by the heater 3, and the gas 4a after the zero reaction in which a thin film is formed on the substrate 5 is discharged from the exhaust port 8.

[Problem that the invention seeks to solve]

In such a conventional thin film forming apparatus, a reaction gas supply lower is provided at one end of the reaction chamber 1, a gas exhaust port 8 is provided at the other end,
Although the reaction gas 4 is made to flow into the reaction chamber 1, it is extremely difficult to maintain a uniform concentration of the reaction gas 4 from the supply lower to the discharge port 8. That is, reaction gas 4
The reaction gas concentration on the substrate 5 along the flow direction of the reaction gas 4 is not constant (usually The reaction gas concentration is high near the reaction gas supply port (the reaction gas concentration decreases as it approaches the gas discharge port 8). Therefore, in the conventional device described above, the intensity of the light beam that causes the photochemical reaction, the substrate temperature, etc. Even if the concentration of the reactant gas 4 is kept constant, it varies on the substrate 5, making it difficult to efficiently produce a high-performance semiconductor with a uniform film thickness.

In addition, since the above conventional device uses a linear lamp as the light source 2, the illuminance distribution on the substrate 5 due to the linear lamp 2 is not uniform both in the axial direction of the lamp and in the direction perpendicular to the axis. It was difficult to form a thin film with uniform thickness.

Furthermore, in the conventional apparatus described above, the reaction gas 4 is supplied to the reaction chamber 1.
The reaction gas 4 also flows to the bottom of the reactor gas 4, which causes problems such as uneven concentration of the reaction gas 4 and pressure fluctuations.

This invention was made to solve these conventional problems, and can suppress non-uniformity in the concentration of the reaction gas and pressure fluctuations, and even if the concentration of the reaction gas on the substrate becomes non-uniform. It is an object of the present invention to provide a semiconductor manufacturing apparatus that can form a thin film of uniform thickness on a substrate even if the illuminance becomes non-uniform.

[Means for solving problems]

In the semiconductor manufacturing apparatus according to the present invention, a table moving mechanism for moving a table on which a substrate is placed is provided, and a peripheral closing member is provided on the table to close a gap formed between the table and the wall surface of the reaction chamber. It was formed.

[Effect]

In this invention, since the substrate is oscillated in the reaction chamber by a table moving mechanism, the amount of reactive gas and the amount of light energy that contribute to film formation on each part of the substrate are determined by the concentration distribution of the reactive gas over the movement range of the substrate.

The amount corresponds to the integral value of the illuminance distribution of light, so even if the respective distributions are non-uniform, the thickness of the thin film formed on the substrate will be uniform in the direction, and as the table moves, Since the gap formed between the table and the wall surface of the reaction chamber is closed by the peripheral closing member, the amount of reaction gas flowing to the lower part of the reaction chamber is reduced, and fluctuations in the concentration and pressure of the reaction gas are suppressed.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a semiconductor manufacturing apparatus according to an embodiment of the present invention. In the figure, 1 is a reaction chamber, 4 is a reaction gas, 1
2 is a light source in which a plurality of linear lamps are arranged in parallel at appropriate intervals in a direction perpendicular to the flow direction of the reaction gas 4; 3 is a heater for heating the substrate; 5 is a substrate; 6 is a light transmitting device. This is a light entrance window made of wood. Further, 7 is a reaction gas supply nozzle, and 8 is a gas discharge nozzle for discharging the gas 4a after the reaction, and the ends of both nozzles 7.8 on the reaction chamber side extend onto the moving table 19 for loading the substrate. There is.

Reference numeral 20 denotes a table moving mechanism that swings the moving table 19 along the flow direction of the reaction gas 4, and this mechanism includes a ball screw 23 screwed into a connector 19a fixed to the table 19, and a ball screw 23 that is driven to rotate. It is composed of a motor 24 that operates.

Further, a peripheral edge closing member 25 is attached to the periphery of the table 19, and is used to close a gap formed between the table 19 and the reaction chamber wall 1b as the table 19 moves. .

Next, the operation will be explained.

In the apparatus of this embodiment, similarly to the conventional apparatus described above, the reaction gas 4 introduced into the reaction chamber 1 causes a photochemical reaction by the light beam projected from the entrance window 6, and this causes the substrate 5 to be heated at a low temperature by the heater 3. A thin film is formed on the surface.

At this time, the moving table 19 is oscillated along the direction in which the reaction gas flows, and each part of the surface of the substrate 5 along the direction is exposed to the reaction gas at each concentration at each position along the direction for the same time. Therefore, the amount of reaction gas to which each part of the surface is exposed is the same as a result of integration. Therefore, even if the concentration distribution along the flow direction of the reactant gas is uneven due to changes in the concentration of the reactant gas due to diffusion of the reactant gas or disturbances in the flow, a thin film with a uniform thickness can be formed. Become.

Furthermore, in this embodiment, a plurality of linear lamps arranged in parallel in a direction perpendicular to the flow direction of the reaction gas 4 is used as the light source 12. Although the illuminance distribution on the substrate 5 along the direction becomes uniform, the illuminance distribution becomes uneven on the substrate 5 along the axial direction of the lamp, which is the flow direction of the gas, as described above. By swinging the substrate 5 in the axial direction, each part of the substrate surface in that direction is exposed to the same intensity of light for the same amount of time, and the film thickness distribution becomes uniform.

Further, in this embodiment, as the table 19 moves, a gap is created between the table 19 and the wall surface of the reaction chamber 1b, but this gap is closed by the peripheral edge closing member 25, so that the reaction gas 4 hardly flows into the lower part 1a of the reaction chamber.

In this way, in this apparatus, the speed of forming a thin film on the substrate 5 is not affected by changes in the intensity of the light beam or uneven concentration of the reactant gas, and a thin film with a uniform thickness can be efficiently formed over the entire surface of the substrate 5. In addition, the amount of reaction gas flowing to the lower part of the reaction chamber can be reduced, and changes in concentration and pressure of the reaction gas can be suppressed, and processing preparation time can be shortened by the amount of gas flowing to the lower part of the reaction chamber. As a result, high-performance semiconductors can be manufactured efficiently and at low cost.

〔Effect of the invention〕

As described above, according to the semiconductor manufacturing apparatus according to the present invention, since the substrate is moved and the gap between the table and the wall surface of the reaction chamber is closed, the uniformity of the film thickness can be improved, and the reaction gas This has the effect of suppressing changes in concentration and pressure, allowing high-performance semiconductors to be manufactured efficiently and at low cost.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of a semiconductor manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional side view of a conventional semiconductor manufacturing apparatus,
FIG. 3 is a cross-sectional view taken along the line II-II of FIG. 2. ■...Reaction chamber, 12...Light source, 4...-Reaction gas,
5... Board, 19... Table, 20... Table moving mechanism, 25... Peripheral closing member. In the drawings, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) In a semiconductor manufacturing apparatus that projects light from a light source onto a reaction gas in a reaction chamber to cause a photochemical reaction and form a thin film on a substrate placed in the reaction gas, a table on which the substrate is placed is used. Semiconductor manufacturing, characterized in that a table moving mechanism for moving the table is provided, and the table has a peripheral closing member that closes a gap formed between the table and the wall surface of the reaction chamber as the table moves. Device.