JP3076276B2 - Belt transport type belt for transporting CVD equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt transport type CV
The present invention relates to a belt for transporting a D apparatus, and more particularly, to a belt for transporting a CVD apparatus which transports a wafer to a film-forming place by placing the wafer on a mesh-shaped transport belt and forms a film.

[0002]

2. Description of the Related Art C used in a process of manufacturing a semiconductor device
In the VD apparatus, as shown in Japanese Patent Application Laid-Open No. 6-20954, first, it is necessary to transport a wafer on a transport belt that circulates to a deposition section where deposition is performed. FIG. 4 is a schematic view of a conventional CVD apparatus. In the figure, reference numeral 1 denotes a transport belt. Reference numeral 2 denotes a motor, which rotates the rotating part 3 and circulates the transport belt 1. Reference numeral 4 denotes a film forming unit. Reference numeral 5 denotes a processing chamber for cleaning a reaction product attached to the belt with an inorganic chemical vapor. 6 is a washing machine for washing the belt cleaned in 5 with pure water. FIG. 5 is FIG.
FIG. 4 is an enlarged schematic diagram of a film forming unit of FIG. Reference numeral 8 denotes a gas blowing unit, 9 denotes a wafer, and 10 denotes a transport belt. Reference numeral 11 denotes a reaction chamber floor of the film forming unit.

Next, the operation will be described. The motor 2 is driven. Then, the rotating portion 3 rotates and the conveyor belt 1 circulates in the direction of the arrow of the belt moving direction. When the wafer 9 is placed on the circulating transport belt 1, the wafer 9
Is transported to the film forming unit 4. In the film forming unit 4, a reactive gas is blown out from the reactive gas blowing unit 8 on the upper side, and a film is formed using heat on the surface of the wafer 9 as an energy source. In the conventional CVD apparatus as described above, a film is formed on the reaction chamber floor 11 immediately below the transport belt 10 through the stitches of the transport belt 10. The transport belt 10 is cleaned in the cleaning processing chamber 5 in a circulating process.
However, the film-forming components adhering to the reaction chamber floor 11 immediately below the transport belt 1 are accumulated with use of the apparatus and gradually become thicker. Excessive film formation on the reaction chamber floor 11 causes an obstacle in film formation characteristics, film quality, and wafer 9 transfer on the surface of the wafer 9. Therefore, after using the device for a certain period of time,
It is necessary to clean the reaction chamber floor 11. The cleaning of the reaction chamber floor 11 is performed by cleaning with the inorganic chemical liquid vapor similarly to the cleaning of the transport belt 10.
In the cleaning, the attachment and detachment of the conveyor belt 10,
Because it involves lowering and raising the temperature of the reaction chamber and removing the chemical solution residue,
Very time consuming. For this reason, the apparatus downtime is long, causing a reduction in the apparatus operating time, which hinders production.

[0004]

Conventionally, Japanese Patent Laid-Open No. 6-20 / 1994
A transfer belt used in a CVD apparatus as disclosed in Japanese Patent No. 954 is a circle or
An elliptical shape is used. The amount of the reaction product deposited on each part in the reaction chamber is proportional to the surface area of each part. Thus, as with the reaction chamber floor, reaction products adhere to the transport belt, but the amount of adhesion to the transport belt is extremely small, and most of the reaction products are deposited on the reaction chamber floor. Therefore, reaction products accumulate on the floor of the reaction chamber within a short time,
Periodic maintenance for cleaning in the apparatus is required. In other words, how to reduce the amount of reactive products deposited on the floor of the reaction chamber is the point of whether the regular maintenance frequency can be extended or prolonged. The problem to be solved by the present invention is to attach a large amount of excess reaction products generated in a film forming section to a transport belt that is sequentially cleaned in the apparatus in a CVD apparatus that transports a wafer by a transport belt. This is to extend the frequency of regular maintenance.

According to the present invention, in a CVD apparatus in which a wafer is placed on a transport belt circulating and transported to a film-forming place to form a film, reaction products generated therefrom are sequentially removed in the apparatus when the film is deposited. The purpose is to achieve a longer and longer periodic maintenance frequency of the CVD equipment by minimizing the amount of reaction products deposited on the floor of the reaction chamber by attaching a large amount to the conveyor belt to be cleaned. And a belt for transporting wafers.

[0006]

SUMMARY OF THE INVENTION The present invention is a transfer belt used in a CVD apparatus for transferring a wafer by a transfer belt. In order to solve the above-mentioned problems, by increasing the surface area of the transport belt, a large amount of reaction products generated therefrom adhere to the transport belt which is sequentially cleaned in the apparatus, and the reaction products deposited on the floor of the reaction chamber. It is a means to minimize the quantity of things.

[0007] increasing the surface area of the conveyor belt according to the present invention
To increase the diameter, use a wire with a small diameter,
Can be increased by braiding
desirable.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the means for increasing the surface area of the conveyor belt used in the present invention includes at least one of the following means (a), (b) and (c).

(A) Using a wire material having a small wire diameter,
Or a means to increase the surface area by braiding into a braid.

(B) Means for increasing the surface area by reducing the surface roughness by bead blasting or sand blasting the wire surface.

(C) Means for increasing the surface area by immersing the wire in an acid-based or alkali-based chemical solution to reduce the surface roughness.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment will be described.

As shown in FIG. 1, the surface area is increased by using a wire having a small diameter and knitting it into a spiral shape or a braid shape. The surface area is increased by about 33% by using and knitting a wire having a diameter of 1/3 of the conventional wire diameter.

Next, a second embodiment will be described.

As shown in FIG. 2, the surface area is increased by reducing the surface roughness by bead blasting or sand blasting the surface of the wire. In order to increase the surface area more efficiently, it is necessary to perform extremely fine blasting.

Next, a third embodiment will be described.

As shown in FIG. 3, the surface area is increased by immersing the wire in an acid-based or alkaline-based chemical solution to reduce the surface roughness. In order to carry out the present embodiment most effectively, as a wire, a wire having a larger diameter than before is prepared, and the wire is immersed in an erosive chemical solution.
It is effective to reduce the surface roughness. By using a slightly thicker wire in advance in consideration of erosion, an equivalent wire diameter can be obtained.

[0018]

As described above, the CVD according to the present invention is performed.
When the transfer belt is used, the surface area is increased to increase the amount of reaction product adhered, and on the other hand, the amount of adhered transfer product to the reaction chamber floor is reduced. Therefore, the frequency of the periodic maintenance for cleaning the reaction chamber floor can be extended.

[Brief description of the drawings]

FIG. 1 is a sectional view of a transport belt according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a transport belt according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a transport belt according to a third embodiment of the present invention.

FIG. 4 is a schematic view of a conventional CVD apparatus.

FIG. 5 is an enlarged schematic diagram of a film forming unit in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveyor belt 2 Motor 3 Rotating part 4 Film-forming part 5 Cleaning processing chamber 6 Washer 7 Belt moving direction 8 Reaction gas blowing part 9 Wafer 10 Conveyor belt 11 Reaction chamber floor

Claims (2)

(57) [Claims] 1. A belt transport type CVD apparatus transport belt for carrying a wafer on a transport belt circulating and transporting the wafer to a transport belt on a floor of a reaction chamber at a film forming place to deposit a reaction product. A belt for transporting a belt-transfer type CVD apparatus, characterized in that the amount of adhering to the conveyor belt is increased by means for increasing the surface of the belt, thereby reducing the deposition on the floor of the reaction chamber and extending the maintenance frequency of the apparatus. 2. The means for increasing the surface area of the conveyor belt uses a wire having a small diameter, and has a spiral shape or a braid shape.
The belt for conveying a belt-conveying type CVD apparatus according to claim 1, wherein the belt is increased by knitting in a shape .