JPH0638404B2 - Semiconductor manufacturing equipment - Google Patents

Description

The present invention relates to a method for photochemically decomposing a reaction gas to form a thin film on a substrate (photo chemical vapor deposition).
n: hereinafter referred to as photo-excited CVD method) relates to a semiconductor manufacturing apparatus for forming a thin film.

[Conventional technology]

Although the CVD method is an important technique for forming a thin film in an integrated circuit device, the conventional CVD method mainly heats a reaction gas to cause a chemical reaction, which causes a high reaction temperature. The thin film formed by is susceptible to damage.

Therefore, recently, a photoexcited 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 as compared with the conventional thermal-excited CVD method, plasma CVD method, etc., and damage to the thin film can be prevented. Can be reduced.

In addition, it is generally known that, in the photo-excited CVD method, the intensity of light has a great influence on the formation rate of a thin film, and under conditions where the substrate temperature, the composition ratio of the reaction gas, and the pressure are kept constant, the thin film It is known that the formation rate of slag increases in proportion to the irradiation intensity of light.

FIG. 3 shows the basic structure of a conventional thin film forming apparatus using such a photo-excited CVD method. In the figure, 1 is a reaction chamber in which the pressure is reduced to a high vacuum during film formation, and 2 is a linear lamp. , 3 is a heater for heating a substrate, 4 is a reaction gas such as silane, 5 is a substrate on which a thin film is formed, 6 is a light incident window made of a light transmitting material, 7 is a reaction gas supply port, and 8 is after reaction Gas outlet for discharging the gas 4a of the
It is a fixed stand on which to mount.

The inside of the reaction chamber 1 is generally depressurized to a high vacuum state, and the wall of the reaction chamber 1 and the light entrance window 6 made of a light transmitting material are naturally constructed to have a structure and a plate thickness capable of withstanding this pressure.

In this apparatus, when the reaction gas 4 is introduced into the reaction chamber 1 from the supply port 7, the reaction gas 4 is excited and decomposed by the light beam projected from the incident window 6. Then, the reaction product generated thereby is deposited on the substrate 5 heated at a low temperature by the heater 3, and a thin film is formed on the substrate 5. Gas 4 after reaction
a is discharged from the discharge port 8.

[Problems to be solved by the invention]

In this conventional semiconductor manufacturing apparatus, the light incident window 6 is provided in the reaction chamber 1 and light is projected from the light source 2 provided outside the reaction chamber 1 as described above, but a thin film is formed on the substrate 5. In order to increase the speed, it is necessary to increase the irradiation of light on the substrate 5. For this purpose, a light source with a larger output is used, or the distance between the substrate 5 and the light source 2 is shortened to increase the illuminance on the substrate 5. There is a need to. However, it is currently difficult to find a practical light source having a long life and a large output, and it is also possible to shorten the distance between the substrate 5 and the light source 2 with the conventional structure by using a light transmitting material. It was very difficult because the light entrance window 6 had to be attached to the reaction chamber 1 with a structure capable of withstanding a high vacuum pressure.

Further, there is a problem that reaction products are deposited on the light incident window 6 to cause so-called clouding, and short-wave ultraviolet rays are difficult to pass through.

The present invention has been made to solve such problems, and to obtain a semiconductor manufacturing apparatus capable of increasing the illuminance of light on a substrate and further solving the problem of light shielding due to the deposition of reaction products. The purpose is.

[Means for solving problems]

The semiconductor manufacturing apparatus according to the present invention uses, as a light source, one in which a plurality of linear lamps are arranged in a quartz glass tube in a reaction chamber, and is set in a state of covering the substrate side portion of the outer peripheral surface of the quartz glass tube. A film drive device for moving the ultraviolet transparent film is provided.

[Operation] In the present invention, since the light source is provided in the reaction chamber, the light source approaches the substrate, the illuminance of light on the substrate increases, and the thin film is formed quickly. Further, since the film covering the lower part of the quartz glass tube is provided, the reaction product adheres to the film and the surface of the quartz glass tube is not fogged by winding the film.

〔Example〕

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

1 is a sectional side view of a semiconductor manufacturing apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line II-II of FIG. In both figures, 1 is a reaction chamber, 13 is a rotatable cylindrical quartz glass tube provided in the reaction chamber 1, and 12 is a plurality of linear lamps arranged along the inner wall of the quartz glass tube 13. , 16 is a motor for rotating the quartz glass tube 13, 1
Reference numeral 4 denotes an ultraviolet transparent film, which is provided on the outer peripheral surface of the cylindrical quartz glass tube 13 on the side of the substrate so as to cover it. Reference numeral 15 is a film driving device for moving the film 14 in the rotational direction of the cylindrical quartz glass tube 13 in synchronism with the quartz glass tube 13 to wind the film, and 15a and 15b are film supply rollers and take-up rollers of the driving device 15. Is. Further, 3 is a heater for heating a substrate, 4 is a reaction gas, 5 is a substrate, 7 is a reaction gas supply port, 8 is a gas discharge port for discharging the gas 4a after the reaction, and 19 is a substrate 5 mounted thereon. A moving table that moves in a direction perpendicular to the axis of the cylindrical quartz glass tube 13, and 20 is a table moving mechanism that drives the moving table 19. This is a ball screw 23 screwed to a connector 19a fixed to the table 19. And a motor 24 for rotating the same. Reference numeral 11 is a reaction gas supply nozzle provided at one end of the cylindrical quartz glass tube 13 on the curved surface side, and 21 is a gas discharge provided on the opposite side of the nozzle 11 so as to sandwich the cylindrical quartz glass tube 13 with the supply nozzle 11. It is a nozzle.

Next, the function and effect will be described.

In this apparatus, the reaction gas 4 is supplied from the supply port 7 to the reaction chamber 1
Light is projected from the cylindrical quartz glass tube 13 which is the light source 12, and the reaction gas 4 causes a photochemical reaction to form a thin film on the substrate 5 heated by the heater 3. In the apparatus, a cylindrical quartz glass tube 13 having a plurality of linear lamps arranged therein is used as a light source.
Since the light source 12 is provided in the reaction chamber 1, the light source 12 can be brought close to the substrate 5 by an arbitrary distance, and the illuminance of light on the substrate 5 can be increased. Therefore, the speed of forming the thin film on the substrate 5 can be increased without increasing the output of the light source more than necessary.

Further, in forming the thin film, the reaction product tends to adhere to the surface of the quartz glass tube 13, but this adheres to the film 14 provided on the surface, and the film 14 is sequentially wound up to form the quartz film. No reaction product adheres to the surface of the glass tube 13. Further, since the film 14 moves in synchronization with the rotation speed of the quartz glass tube 13, no dust is generated between the two.

Further, in this embodiment, since the reaction gas supply nozzle 11 and the gas discharge nozzle 21 are provided below the glass tube 13 with the cylindrical quartz glass tube 13 interposed therebetween, the reaction gas 4 is the cylindrical quartz glass tube 13 and the substrate 5. And the reaction gas 4 flows through a place where the illuminance of light on the substrate 5 is strongest.
It is possible to cause a photochemical reaction to occur rapidly. Further, by providing these nozzles 11 and 21, it is only necessary to flow the reaction gas 4 for a short distance, and therefore it is possible to prevent the reaction gas 4 from flowing to unnecessary portions in the reaction chamber 1. Further, since the reaction gas can be efficiently flowed over a short distance, the concentration of the reaction gas can be made uniform, and a sufficient amount of the reaction gas can be flown onto the substrate 5 in accordance with the photochemical reaction rate of the reaction gas. The formation rate of the thin film can be increased.

Further, since the linear lamps are arranged in the cylindrical quartz glass tube 13 along the inner wall of the glass tube 13 at appropriate intervals, the linear lamps are placed on the substrate 5 in the direction perpendicular to the axis of the glass tube 13. The illuminance distribution of light can be made uniform to some extent, and the moving table 19 is moved in that direction, so that the illuminance distribution of light in that direction can be made more uniform, so that a uniform thin film is continuously formed on the substrate 5. Can be formed.

Further, since the reaction gas supply nozzle 11 and the gas discharge nozzle 21 are provided with the cylindrical quartz glass tube 13 interposed therebetween, the reaction gas flows along the moving direction of the moving table 19, and the reaction gas flows along the flowing direction. It is possible to avoid the influence of a slight change in the concentration of the reaction gas on the change in film thickness on the thin film formed.

〔The invention's effect〕

As described above, according to the semiconductor manufacturing apparatus of the present invention, a plurality of linear lamps incorporated in a quartz glass tube is used as a light source, and the light source is provided in the reaction chamber.
The illuminance of light on the substrate can be increased to accelerate the thin film formation speed, and since the quartz glass tube surface film is provided and is moved and wound up, it is possible to prevent the surface from being fogged. effective.

[Brief description of drawings]

1 is a sectional side view of a semiconductor manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional side view of a conventional semiconductor manufacturing apparatus. 1 is a reaction chamber, 12 is a light source, 4 is a reaction gas, 5 is a substrate, 1
3 is a quartz glass tube, 14 is an ultraviolet transparent film, and 15 is a film winding device. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (2)

[Claims] 1. A semiconductor manufacturing apparatus for projecting light from a light source onto a reaction gas in a reaction chamber to cause a photochemical reaction to form a thin film on a substrate placed in the reaction gas, wherein the light source is the reaction chamber. A plurality of linear lamps are arranged in a quartz glass tube provided in the film driving device for moving the ultraviolet transparent film in a state of covering the substrate side portion of the outer peripheral surface of the quartz glass tube. A semiconductor manufacturing apparatus characterized in that 2. The quartz glass tube is rotatable, and the moving speed of the ultraviolet transparent film is the same as the peripheral speed of the quartz glass tube. Semiconductor manufacturing equipment.