JPH058672Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention provides a vapor phase growth apparatus suitable for cases where a large amount of decomposition products are generated as a result of the vapor phase growth reaction, such as in metal organic heat treatment (MOCVD). It is something to do.

[Conventional technology]

There are various conventional apparatuses for carrying out the above-mentioned vapor phase growth, and FIG. 2 will be explained by illustrating a central longitudinal sectional view of a vertical vapor phase growth apparatus as an example.

In the figure, 1 is a cylindrical reaction tube having an opening 1a at the bottom, 2 is a front chamber connected to the bottom opening 1a of the reaction tube 1, and the reaction tube 1 and the front chamber 2 are connected to the bottom of the front chamber 2. They are airtightly partitioned or communicated by a lid member 3 that passes through them and moves up and down. The reaction tube 1 performs vapor phase growth inside, and has a reaction gas introduction part 4 at the top.
It has a reaction gas discharge part 5 below, and an O ring 6.
The reactor tube 1 is formed so that it can be divided into upper and lower parts via an airtight connecting member, and is provided with a high frequency coil 7 wound around the outer periphery of the reaction tube 1 at appropriate intervals as one of the heating means. The front chamber 2 is a box having an entrance 8 for loading and unloading wafers 11 into the reaction tube 1, and a lid member 3 passing through the bottom of the front chamber 2 is located at the upper end of the hollow tube 3a. It has a flange 3b that can close the bottom opening 1a of the reaction tube 1. Reference numeral 9 denotes a shaft member that airtightly penetrates the lid member 3 and extends into the reaction tube 1 at one end and outside, and is movable up and down as well as rotatable, and a susceptor 10 is installed at the upper end. has been done.

The susceptor 10 is made of carbon and has a cylindrical shape, for example, and is heated by induction by the high frequency coil 7 to heat the wafer 11 placed on the upper surface by heat transfer.

A method of operating the conventional vapor phase growth apparatus configured as described above will be explained.

The shaft member 9 was moved down together with the lid member 3 to position the susceptor 10 near the entrance 8 of the front chamber 2, and then the processed wafer was picked up from above the susceptor 10, and the unprocessed wafer was placed on the susceptor 10. After that, the shaft member 9 is moved upward together with the lid member 3,
The bottom opening 1a of the reaction tube 1 is connected to the flange 3b of the lid member 3.
while airtightly closing the shaft member 9,
The susceptor 10 is set at a predetermined position within the reaction tube 1.

After purging the inside of the reaction tube 1 by introducing an inert gas such as nitrogen gas from the reaction gas introduction part 4 as shown by the arrow and discharging it from the reaction gas discharge part 5,
Gases necessary for vapor phase growth such as arsine and phosphine are introduced from the reaction gas introduction section 4, and the high frequency coil 7 is energized to heat the susceptor 10, thereby heating the wafer 11 to a predetermined temperature and performing vapor phase growth on the wafer 11. Do this. Note that during the vapor phase growth, the shaft member 9 is appropriately rotated so that a uniform film is formed on the wafer 11.

After completing the vapor phase growth process, the inside of the reaction tube 1 is again purged with an inert gas, and then the operation returns to the above.

Through the above operations, a vapor phase growth film can be formed on the wafer 11. In the above-mentioned vapor phase growth apparatus, the reaction gas introduced into the reaction tube 1 causes a thermal decomposition reaction on the top of the heated wafer 11, and decomposition products are deposited on the wafer 11, causing gaseous growth. When forming a phase-grown film, a part of the product adheres and accumulates on the inner wall surface of the reaction tube 1 other than the wafer, gradually increases in thickness and becomes easy to peel off, and the wafer 11
There is an inconvenience that the product falls and adheres to the surface of the vapor-phase grown film above, resulting in a defective product. For this reason, conventionally, the reaction tube 1 has been appropriately disassembled using the O-ring 6 portion to clean the inside.

[Problem that the invention attempts to solve]

However, not only is it necessary to frequently clean the inner wall surface of the reaction tube, but also it is time-consuming to disassemble and assemble the reaction tube. In addition, many of the decomposition products that adhere to the inner walls of reaction tubes are harmful to the human body, so special safety measures are required during disassembly, cleaning, and assembly. , moisture, etc., so even if purged with high-purity nitrogen, the quality of the grown film deteriorates during several vapor phase growths immediately after cleaning. The various inconveniences associated with such cleaning become a serious problem in reactions such as organometallic heat treatment, in which a large amount of decomposition products are produced as a result of the vapor growth reaction, as cleaning becomes more frequent.

[Structure of the idea]

In view of the above-mentioned disadvantages, the present invention has devised a vapor phase growth apparatus that can solve the above-mentioned disadvantages with a simple configuration using a shaft member that was conventionally used only for raising, lowering, and rotating the susceptor. The reason for this is that the end of the shaft member, the susceptor, and the brush for cleaning the inner wall surface of the reaction tube are attached and detached so that they can be replaced at the end of the shaft member, and the susceptor and brush are connected to the outside in the front chamber. The purpose is to provide an operation means that can be replaced while maintaining airtightness.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1, in which the same components as those in FIG. 2 are designated by the same reference numerals.

FIG. 1 is a longitudinal cross-sectional view of a vapor phase growth apparatus according to the present invention. The difference from FIG. 2 according to the conventional example is that a shaft member 9 is connected at an end to a susceptor 10 and a brush 20 for cleaning the inner wall surface of the reaction tube. The glove box 21 is provided in the front chamber 2 so that the glove box 2 can be replaced without being exposed to the atmosphere. The above-mentioned attachment/detachment structure will be described in detail. The brush 20 has a plurality of brushes on the surface of a hollow cylindrical body, for example, and a recess into which the end of the shaft member 9 can be fitted is formed at the bottom. A similar recess is also formed in the susceptor 10. Note that, in addition to the above-mentioned fitting structure, any conventionally known attachment/detachment structure such as a screwing structure can be used for the attachment/detachment structure between the end portion of the shaft member 9, the brush 20, and the susceptor 10. Further, the shape of the brush 20 is not limited to the above-mentioned shape, and may be arbitrary. Furthermore, a plurality of rod-shaped brushes may simply be attached to the end of the shaft member 9.

Next, the glove box 21 is a box connected to the front chamber 2 through an opening/closing door 22, and a glove 23 as an operating means for exchanging the susceptor 10 and the brush 20 is provided on the outer wall. Note that the glove box 21 can be formed as a part of the front chamber 2 without providing the opening/closing door 22, but the inside of the front chamber 2 may be evacuated for cleaning, and the brush 20 may be taken out to the outside. In some cases, it is preferable to provide an opening/closing door 22 so as not to affect the front chamber 2 to form a separate space. Note that 24 and 25 are an exhaust pipe and an exhaust valve, respectively, which are provided at the outer lower end of the lid member 3 in communication with an exhaust system (not shown).

Next, to clean the inner wall surface of the reaction tube 1 with the above-mentioned configuration, first, the treated wafer is picked up from the susceptor 10 by the above-mentioned method and carried out to the outside of the machine, and then the opening and closing door 22 is opened using the globe 23, the susceptor 10 is removed from the shaft member 9, and the brush 2 is used instead.
0 and close the opening and closing door 22.

The shaft member 9 is moved upward together with the lid member 3 to close the opening 1a of the reaction tube 1 with the lid member 3, and the brush 20 is set at an appropriate position within the reaction tube 1.

An inert gas is introduced into the reaction tube 1 as shown by the arrow from the reaction gas introduction section 4 and the reaction gas discharge section 5, and is exhausted through the exhaust valve 25 to purge the inside of the reaction tube 1. Move up and down while rotating 9.

In this way, the brush 20 is rotated up and down via the shaft member 9 to clean the inner wall surface of the reaction tube 1, and after forcibly peeling off the attached decomposition products, the exhaust system outside the machine is removed by a flow of nitrogen gas. to be discharged.

When cleaning is completed, both the lid member 3 and the shaft member 9 are moved down, the opening/closing door 22 is opened using the glove 23, the brush 20 is removed, the susceptor 10 is attached in its place, and the opening/closing door 22 is closed. Thereafter, the unprocessed wafer is placed on the susceptor 10 and vapor phase growth processing is performed in the same manner as in the conventional method.

The above-described operations can be performed at any time after completing the processing on one wafer, and thereby the vapor phase growth processing can be performed in good condition at all times.

In this embodiment, a valve 25 is provided at the external lower end of the lid member 3 to discharge the decomposed products during cleaning, but the valve 25 is provided at the lower end of the reaction tube 1 and at a position where the decomposed products do not accumulate. Furthermore, the reaction gas discharge section 5 may also be used, and a separate decomposition product discharge pipe may not be provided.

Further, in this embodiment, the susceptor 10 and the brush 20
Although the glove box 21 is used as the operation means for exchanging the parts, it is also possible to use a remote control means such as a manipulator.

Next, in this example, the explanation was given using a vertical vapor phase growth apparatus in which the reaction gas flows from top to bottom, but the invention is not limited to this, and the application can also be applied to a horizontal vapor phase growth apparatus.
In this case, the glove box 21 and the decomposition product discharge section are arranged at suitable positions. Furthermore, the present invention is not limited by the heating means attached to the reaction tube,
In addition to induction heating as in this embodiment, lamp heating can also be used without any problem.

[Effect of idea]

As described above, according to the present invention, a brush for cleaning the inner wall surface of a reaction tube can be removably attached to the end of the shaft member, using the shaft member conventionally used simply for rotating and moving the susceptor. With this structure, (1) Since air does not enter the reaction tube and there is no contamination, there is no quality deterioration even during vapor phase growth immediately after cleaning, productivity is significantly improved, and the implementation effect is large.

(2) There is no need to disassemble and reassemble the reaction tube to clean the inner wall surface of the reaction tube as in the past, and as a result, the harmful decomposition reaction products that adhere to the inner wall surface of the reaction tube do not come into contact with the operator. No special safety measures are required for the work, which makes the work easier and the labor of cleaning work can be significantly reduced.

(3) Furthermore, the present invention is applicable not only to organometallic heat treatment methods, but also to
It is highly practical because it can be applied to various types of vapor phase growth, and because it has a simple configuration, it can be implemented with a slight modification of a conventional vapor phase growth apparatus.

[Brief explanation of drawings]

FIG. 1 is a central vertical cross-sectional view showing an embodiment of the device of the present invention, and FIG. 2 is a central vertical cross-sectional view showing an example of the conventional device. 1... Reaction tube, 2... Front chamber, 3... Lid member, 4
... Reaction gas introduction section, 5 ... Reaction gas discharge section, 9
... Shaft member, 10 ... Susceptor, 11 ... Wafer, 20 ... Brush, 21 ... Glove box, 22 ... Opening/closing door, 23 ... Glove.

Claims (1)

[Scope of utility model registration request] a reaction tube formed by a cylindrical body having an opening at one end, provided with a reaction gas introduction part and a reaction gas discharge part, and provided with a heating means; a reaction tube connected to the reaction tube through the opening for carrying in a wafer; A front room for carrying out the work,
a lid member that airtightly penetrates the front chamber to open and close an opening of the reaction tube; a lid member that airtightly penetrates the lid member and extends into the reaction chamber; a susceptor is installed at an end of the lid member; A vapor phase growth apparatus comprising a shaft member that can move forward and backward, and a detachable structure in which an end of the shaft member and a brush for cleaning the susceptor and the inner wall surface of the reaction tube can be replaced at the end of the shaft member. A vapor phase growth apparatus characterized in that the front chamber is provided with an operating means that allows the susceptor and the brush to be replaced while maintaining airtightness from the outside.