JPH06283463A - Semiconductor manufacturing equipment - Google Patents

Abstract

PURPOSE:To conduct a pretreatment using corrosive gas and an after treatment, that is, a washing process, in one and the same reaction chamber by flattening the inner surface of a metallic section in the reaction chamber and an exhaust system or an exhaust gas processing section to a specific surface roughness. CONSTITUTION:An exhaust line 12 which exhausts gas through a furnace flange 6, a gate valve 11 and a vacuum pump 10 is constituted of the furnace flange 6 which is located below a tube 5 and which constitutes a part of a film formation chamber and which etching gas composed of reactive gas and corrosive gas are brought into contact with, the pump 10 which evacuates the film formation chamber, and the gate valve 11 which partitions the pump 10 and the film formation chamber. The inner surface of a metallic section of the exhaust line 12 is flattened to a surface roughness of 10mum or below by, for example, composite electrolytic polishing. By this method, a resistance to corrosion by corrosive gas can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus in which the corrosion resistance of a reaction processing chamber, an exhaust system or an exhaust gas processing section is improved.

[0002]

2. Description of the Related Art In manufacturing a semiconductor device, a process of forming a thin film such as a polysilicon film, an oxide film or a nitrogen film, which is a component of a device, on a semiconductor substrate by using a heat treatment device or a CVD device. It is used a lot. In these processes, the cleanliness of the thin film and the semiconductor substrate surface before and after etching often have a great influence on the characteristics and reliability of the device used as a product, and various wafer cleaning processes are performed. Attention has also been paid to the contamination of the wafer between and.

In particular, when a semiconductor substrate is put in or taken out of a heat treatment apparatus, a CVD apparatus or the like, an oxide film may be formed on the substrate by being exposed to the outside air, and this oxide film causes a problem of deterioration of device characteristics and reliability. Become. Therefore, there is a need for an apparatus having a mechanism for suppressing the growth of this oxide film.

In the conventional heat treatment film forming apparatus, in order to suppress the natural oxide film growing on the interface, the semiconductor wafer is immediately inserted into the reaction chamber without any time after pretreatment. It was difficult to try to remove the membrane completely. For example, if the process just before film formation is performed with hydrogen fluoride, hydrogen chloride, etc. in the same reaction processing chamber (tube), the stainless steel conventionally used for the metal part that supports the tube with these corrosive gases The material and the exhaust system piping are corroded, causing an increase in contamination (contamination) and dust (particles), which adversely affects the device. Therefore, the film forming step and the pretreatment step are performed in separate reaction processing chambers, and cannot be performed in the same reaction processing chamber.

RI for etching the formed film
In E equipment, chlorine-based gas, H used in the equipment
Br gas, etc. is also highly corrosive, and if used for a long time
Corrosion of the transport system, exhaust pipe, etc. causes contamination and increase of particles as in the film forming apparatus, and adversely affects the device. Therefore, an apparatus using a metal that can withstand these corrosions is required.

Furthermore, when films such as polysilicon and silicon nitride are continuously formed, polysilicon and silicon nitride are also deposited on the tube in the film forming chamber, and when a certain film thickness is reached, these films are removed from the tube. The film peels off and causes an increase in dust. Therefore, it is necessary to regularly clean the tube. However, it takes time to disassemble, clean, assemble and adjust the tube, and in view of productivity, it is necessary to introduce a self-cleaning process using highly corrosive ClF ₃ gas or the like.

Even in this case, the tube forming the film forming apparatus and the stainless alloy conventionally used for the exhaust system are corroded by the cleaning gas, which causes the same problems as described above.

Further, even in an exhaust gas treatment apparatus of a heat treatment film forming apparatus for performing film formation and etching in an etching apparatus or the same reaction processing chamber, conventional reaction tubes, pumps and associated materials such as valves and pipes are used. The stainless steel or the like is corroded by a highly corrosive etching gas or reducing gas, and in the worst case, there is a possibility that a hole is opened and a toxic or flammable gas leaks from the hole.

[0009]

As described above,
In a conventional semiconductor manufacturing apparatus that uses a corrosive gas, a metal part that is in contact with the corrosive gas is corroded.
Therefore, the reaction processing chamber is contaminated and the cleanliness is lowered, which adversely affects the characteristics of the manufactured device.

Further, even in the exhaust system of the corrosive gas used in the reaction processing chamber and the exhaust system such as the valve and the pipe, the metal portion in contact with the corrosive gas is corroded as described above. Therefore, corrosive gas may leak from the corroded metal part.

On the other hand, in order to avoid the above-mentioned problems, the step of using a corrosive gas may be carried out in a dedicated processing chamber prepared separately. However, in the case where a dedicated processing chamber is separately provided for processing, it takes time to increase the equipment and move the wafer, resulting in a decrease in productivity.

Therefore, the present invention has been made in view of the above, and an object of the present invention is to improve the corrosion resistance to a corrosive gas so that a corrosive gas is generated in the same reaction processing chamber. It is an object of the present invention to provide a semiconductor manufacturing apparatus capable of performing the pretreatment and the post-treatment cleaning treatment used.

[0013]

In order to achieve the above object, the invention according to claim 1 is a reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer,
An exhaust system for exhausting the gas introduced into the reaction processing chamber or /
And an exhaust gas processing part for processing the exhaust gas exhausted from the reaction processing chamber through the exhaust system, and the inner surface of the metal part in the reaction processing chamber and the exhaust system or / and the exhaust gas processing part is 10
It is configured by flattening to a surface roughness of μm or less.

According to a second aspect of the present invention, a reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, and an exhaust system for exhausting the gas introduced into the reaction processing chamber and / or a reaction treatment are provided. It has an exhaust gas treatment part that treats the exhaust gas exhausted from the chamber through the exhaust system, and the reaction process chamber and the metal part in the exhaust system and / or the exhaust gas treatment part are made of stainless steel, and the inner surface is passivated. Processed and configured.

According to a third aspect of the present invention, a reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, and an exhaust system for exhausting the gas introduced into the reaction processing chamber and / or a reaction treatment are provided. An exhaust gas processing unit for processing exhaust gas exhausted from the chamber through the exhaust system, and the reaction processing chamber and the exhaust system or / and the metal part in the exhaust gas processing unit are formed of stainless steel, and the inner surface thereof is 10 μm or less. It is constructed by flattening to surface roughness and then passivation treatment.

The invention according to claim 4 is a reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, and an exhaust system for exhausting the gas introduced into the reaction processing chamber and / or a reaction treatment. Has an exhaust gas processing part for processing exhaust gas exhausted from the chamber through the exhaust system, and the reaction processing chamber and the exhaust system or / and the metal part in the exhaust gas processing part is formed of an aluminum alloy material, and the inner surface thereof is 10 μm or less. Is formed by flattening to a surface roughness of 1 to form an underlayer, and then passivation treatment.

According to a fifth aspect of the present invention, in the semiconductor manufacturing apparatus according to the second, third or fourth aspect, the underlayer is made of nickel phosphorus, and the passivation treatment is performed on the stainless material or the underlayer with stainless steel. Is formed by forming a fluorine compound layer with a partial substance or nickel.

The invention according to claim 6 is the same as claim 1,
In the semiconductor manufacturing apparatus described in 3, 4, or 5, the processing gas is a corrosive gas such as a chlorine-based gas or a halogen-based gas.

[0019]

According to the present invention, the metal surface of the reaction treatment chamber and the exhaust system or / and the exhaust gas treatment unit, which is in contact with the corrosive gas, is flattened or flattened and coated with a passive film.

[0020]

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

FIG. 1 is a diagram showing the structure of a semiconductor manufacturing apparatus according to an embodiment of the invention described in claim 1.

The semiconductor device of the embodiment shown in FIG. 1 is a heat treatment film-forming device, particularly an LP-device for forming polysilicon film under reduced pressure.
A CVD apparatus, which is a boat 2 on which a wafer 1 is placed, an elevator mechanism 3 for loading and unloading the wafer 1 together with the boat 2, and a furnace lid 4 which can be moved up and down by the elevator mechanism 3 and on which the boat 2 can be placed , A tube 5 made of quartz which constitutes a part of the film forming chamber which is the center of the apparatus, a furnace opening flange 6 which is below the tube 5 and which forms a part of the film forming chamber, and surrounds the film forming chamber 7, the heater 7 surrounding the heater 7 and the heat insulating material 8 covering the film forming chamber, the film forming gas nozzle 9a introduced into the film forming chamber from the gas supply chamber (not shown), and the pretreatment Gas nozzle 9b, gas nozzle 9 for self-cleaning
c, pump 10 for drawing a vacuum in the film forming chamber, pump 10
And a gate valve 11 for partitioning the film forming chamber, and an exhaust line 12 for exhausting gas from the furnace flange 6 through the gate valve 11 and the vacuum pump 10. The exhausted gas is released through the exhaust gas treatment device shown in FIG.

Further, in this embodiment, the reaction gas, chlorine-based gas such as Cl ₂ , ClF ₃ or HF, HBr.
The inner surface of the metal part made of, for example, an aluminum alloy in the exhaust system including the furnace port flange 6 and the vacuum pump 10, the gate valve 11, and the exhaust line 12, which come into contact with the etching gas including the corrosive gas of halogen-based gas such as In order to improve the corrosion resistance to corrosive gas, it is characterized in that the surface roughness (Rmax) is flattened by, for example, a composite electrolytic polishing treatment so as to be 10 μm or less.

Next, the operation status and operation will be described.

Here, a method for forming a polysilicon film will be described as an example.

The furnace lid 4 located in the film forming chamber is lowered. The wafer 1 is mounted on the board 2 placed on the furnace lid 4 by the wafer transfer machine 13 and lifted up into the film forming chamber by the elevator mechanism 3 to seal the film forming chamber and the furnace lid 4.

After that, the exhaust pump 10 is operated to exhaust the film forming chamber. Next, a gas for etching an oxide film such as hydrogen fluoride is caused to flow from the gas nozzle 9b for pretreatment in the vacuum state or while purging an inert gas (for example, high-purity nitrogen), and the surface of the wafer 1 is subjected to the gas treatment. The grown natural oxide film is removed, the inside is evacuated again, and a vacuum and an inert gas (for example, nitrogen) purge are combined to eliminate residual etching gas. Further, after the deposition temperature of the polysilicon is raised and stabilized while maintaining a vacuum state or purging an inert gas such as nitrogen gas, a reaction gas is flown to make a predetermined film formation pressure (10 to 20 Pa). Do the membrane. In this case, a gas for forming the film is formed by flowing a silane gas from the reaction gas nozzle 9a by a known method.

Next, after the film is formed to a predetermined thickness, the film forming processing chamber is once evacuated to eliminate residual silane gas. After that, the furnace lid 4 is lowered, the wafer 1 is taken out of the film forming processing chamber, the wafer 1 is collected by the wafer transfer machine 13, and a series of operations is completed. By repeating this, the polysilicon film is continuously formed.

After depositing the polysilicon several times and after evacuation, the etching gas for self-cleaning is made to flow from the reaction gas nozzle 9c and adhered to the tube, the furnace port flange, etc., similarly to the deposition processing method. Etching the film.

In such an embodiment, the inside of the film forming processing chamber, the exhaust system, and the surfaces of the parts attached thereto are set to Rm.
By using ax to flatten by complex electropolishing to 10 μm or less, the corrosion resistance to the gas used for pretreatment and self-cleaning is improved, and the corrosion of the reaction chamber and the exhaust pipe system due to those treatments is improved. Can be suppressed.

Further, since the corrosion resistance to corrosive gas is improved, pretreatment, deposition and cleaning can be performed in one treatment chamber.

Further, by flattening the inner wall surface of the film forming reaction, the amount of water adsorbed on the inner wall surface is significantly reduced, and the vacuum property can be improved.

Next, an embodiment of the invention described in claim 2 or 3 will be described.

An embodiment of the invention according to claim 2 or 3 is
In the configuration shown in FIG. 1, reaction gas, Cl ₂ , ClF ₃
The exhaust system consisting of the furnace port flange 6 and the vacuum pump 10, the gate valve 11 and the exhaust line 12, which are in contact with the etching gas consisting of a corrosive gas such as a chlorine-based gas such as HF, HBr, etc., is made of stainless steel material. FeF and CrF made of a compound of fluorine and F or Cr that forms stainless steel by forming and fluorinating the inner surface
It is characterized in that a passivation treatment is performed by growing and forming a compound layer of about several thousand Å.

In such an embodiment, as shown in FIG. 2, the surface of the gas contacting portion of the metal used for the inside of the film forming chamber and the exhaust pipe is treated with a fluorinated surface of the stainless material, as shown in FIG. The corrosion rate is remarkably reduced, and it has sufficient corrosion resistance against corrosive gases used for pretreatment and self-cleaning, and can suppress the corrosion in the reaction chamber due to those treatments. This is also effective from the viewpoint of preventing contamination due to corrosion.

Further, by carrying out this surface treatment, the stainless steel material that has been used conventionally can be used as it is, so that the problem of strength and the problem of material arrangement can be solved, and the price is almost the same as the conventional one. It is possible to put a heat treatment film forming apparatus with pretreatment and self-cleaning into practical use.

In the above embodiment, the inner surface of the stainless material may be flattened by the method described in the above embodiment and then fluorinated. As described above, the flattening treatment enhances the adhesion of the passivation film coated on the stainless steel surface, and the passivation film itself becomes flat, so that the moisture adsorbed on the inner wall surface of the film formation reaction chamber is significantly increased. And the vacuum property can be improved.

Next, an embodiment of the invention described in claim 4 will be described.

In this embodiment, the reaction gas, Cl ₂ and ClF are used.
_The exhaust system consisting of the furnace flange 6 and the vacuum pump 10, the gate valve 11 and the exhaust line 12 in contact with the etching gas composed of a corrosive gas such as a chlorine-based gas such as ₃ or a halogen-based gas such as HF and HBr is an aluminum alloy. It is characterized in that the inner surface thereof is flattened to Rμ of 10 μm or less (for example, a composite electrolytic polishing treatment), the inner surface is plated with nickel phosphorus, and a fluorinated passivation film is further formed.

In such an embodiment, the inside of the film forming chamber, the exhaust system, and the parts attached thereto are made of aluminum alloy, and the inner surface of the film is nickel-phosphorus-plated and then fluorinated and passivated. As shown in FIG. 3, the corrosion rate is remarkably reduced by the application, and sufficient corrosion resistance to the corrosive gas used for pretreatment and self-cleaning can be obtained. The corrosion of the exhaust pipe system can be suppressed.

FIG. 4 is a diagram showing the structure of an exhaust gas treating apparatus according to an embodiment of the invention described in claims 1 to 4.

The apparatus shown in FIG. 4 is an adsorption tower type exhaust gas processing apparatus of an LP-CVD apparatus for performing in-situ processing and forming polysilicon film under reduced pressure. The vacuum pump 10 of the heat treatment film forming apparatus shown in FIG. A pump 1 which has been subjected to the surface treatment of this embodiment for sucking the unreacted gas and the reaction product which are exhausted further
4, an air mixer 15 which has been subjected to the surface treatment of this embodiment to mix air with the unreacted gas and reaction product sucked by the pump 14, S for capturing SiO ₂ which is a reaction product
iO ₂ trap 16, filter 17 with surface treatment of this example to capture reaction product powder product, this implementation to process unreacted gas and reaction product after capture of powder product The surface-treated reaction tube 18 of the example, the gas treated by the reaction tube 18 are exhausted, the surface-treated exhaust tube 19 of this embodiment, the pump 14 and the air mixer 1
5, the SiO ₂ trap 16, the filter 17, and the reaction tube 1
It is composed of a pipe 20 and a valve 21 which are connected to each other and which are subjected to the surface treatment of this embodiment.

In such a structure, as the surface treatment of this embodiment, the inner surface of the metal portion which is in contact with the corrosive gas is flattened by, for example, complex electrolytic polishing so that the surface roughness becomes 10 μm or less. Alternatively, the metal portion is formed of a stainless material, and the passivation treatment similar to the above is performed by coating the inner surface of the metal portion with a fluorine film.
Alternatively, the passivation process may be performed after the stainless material is flattened. Further, as the surface treatment of this embodiment, a metal portion which is exposed to a corrosive gas is formed of an aluminum alloy material, the inner surface of which is flattened to have a surface roughness of 10 μm or less, and then an underlayer of nickel phosphorus plating is formed. However, a passivation treatment may be performed by coating a fluorine film on the underlayer of nickel phosphorous plating.

Next, the operation of the device shown in FIG. 4 will be described.

Here, as an example, the exhaust gas treatment of the adsorption tower type exhaust gas treatment apparatus of the LP-CVD apparatus for polysilicon film formation shown in FIG. 1 will be described.

Unreacted gas and reaction products exhausted from the LP-CVD apparatus are exhausted by the pump 10 of the LP-CVD apparatus and diluted with N ₂ . The diluted unreacted gas and reaction products are sucked by the pump 14 of the exhaust gas treatment device and are sucked by the air mixer 15 to the pump 1 of the exhaust gas treatment device.
SiO 2 after mixing with external air to a volume of 4
₂ Trap 16 is used to remove the reaction product, SiO ₂ .
%, And the remaining reaction product is captured by the filter 17. After that, the unreacted gas and the residual gas after the reaction after the powder reaction product is trapped pass through the pump 14 and enter the reaction tube 18, and are completely trapped and absorbed by the catalytic action. The treated gas is discharged into the atmosphere through the exhaust pipe 19.

Unreacted gas and reaction products exhausted from the LP-CVD apparatus for performing in-situ treatment include HF gas and chlorine-based gas as etching gas in addition to SiH ₄ , N ₂ and SiO ₂ as film forming gas. , HBr gas, ClF ₃ etc. are processed, but the metal parts, pipes, valves etc. in contact with unreacted gas and reaction products inside the equipment are surface-treated as described above, so that corrosion used for etching Sufficient corrosion resistance to a strong gas is obtained, and it is possible to suppress the corrosion of the reaction tube, the pump, and the exhaust pipe system due to the treatment thereof.

The present invention is not limited to the above embodiment, and the surface roughness (Rmax) for flattening may be such that the corrosion resistance to corrosive gas can be improved, and the inner wall surface can be improved. It suffices that the amount of water adsorbed on is reduced and the vacuum property is enhanced, and it is preferably set to 1 μm or less.

Further, the combination of the stainless steel material and aluminum alloy material effective as the material of the metal portion and the surface treatment is not limited to the above-mentioned embodiment, and the same effect can be obtained by various combinations. is there.

Further, although the film forming apparatus and the exhaust system and the exhaust gas processing apparatus have been described separately in the above embodiment, in the semiconductor manufacturing apparatus having the film forming apparatus and the exhaust system and the exhaust gas processing apparatus, the film forming apparatus and the exhaust system are provided. It goes without saying that the present invention may be applied to all the system and the exhaust gas treatment device.

[0051]

As described above, according to the present invention, the metal portion which is exposed to corrosive gas is formed of stainless steel or aluminum alloy, and the surface treatment is flattened or flattened. Since the passivation treatment is performed, the corrosion resistance to corrosive gas can be significantly improved as compared with the conventional one. Thereby, the treatment before and after using the corrosive gas can be carried out in the same reaction treatment chamber as the main treatment, and the productivity can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a semiconductor manufacturing apparatus according to an embodiment of the invention described in claims 1 to 6.

FIG. 2 is a diagram showing corrosion rates of a conventional example and an example in which the surface treatment of the present invention is performed.

FIG. 3 is a diagram showing corrosion rates of a conventional example and another example in which the surface treatment of the present invention is performed.

FIG. 4 is a diagram showing a configuration of a semiconductor manufacturing apparatus according to an embodiment of the invention described in claims 1 to 6.

[Explanation of symbols]

1 Wafer 2 Boat 3 Elevator Mechanism 4 Furnace Lid 5 Tube 6 Furnace Flange 7 Heater 8 Heat Retaining Material 9a Film Forming Gas Nozzle 9b Pretreatment Gas Nozzle 9c Self Cleaning Gas Nozzle 10 Pump 11 Gate Valve 12 Exhaust Line 13 Wafer Transfer Machine 14 Pump 15 Air mixer 16 SiO ₂ trap 17 Filter 18 Reaction tube 19 Exhaust tube 20 Piping 21 Valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kuniaki Kumamaru 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Stock company Toshiba Tamagawa factory

Claims (6)

[Claims] 1. A reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, an exhaust system for exhausting the gas introduced in the reaction processing chamber, and / or an exhaust system from the reaction processing chamber. An exhaust gas processing part for processing the exhaust gas exhausted through the exhaust gas, and flattening the inner surface of the metal part in the reaction processing chamber and the exhaust system and / or the exhaust gas processing part to a surface roughness of 10 μm or less. Characteristic semiconductor manufacturing equipment. 2. A reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, an exhaust system for exhausting the gas introduced in the reaction processing chamber, and / or an exhaust system from the reaction processing chamber. It has an exhaust gas processing part for processing the exhaust gas exhausted via the reaction process chamber and the exhaust system and / or the metal part in the exhaust gas processing part is made of stainless steel, and its inner surface is passivated. A semiconductor manufacturing apparatus characterized by the above. 3. A reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, and an exhaust system for exhausting the gas introduced into the reaction processing chamber, and / or an exhaust system from the reaction processing chamber. An exhaust gas treatment unit for treating the exhaust gas exhausted through the reaction chamber, the reaction treatment chamber and / or the exhaust system or / and the metal portion of the exhaust gas treatment unit are made of stainless steel, and the inner surface thereof is 10 μm.
A semiconductor manufacturing apparatus, which is obtained by performing passivation treatment after flattening to the following surface roughness. 4. A reaction processing chamber in which a reaction gas or a processing gas is introduced to process a semiconductor wafer, and an exhaust system for exhausting the gas introduced into the reaction processing chamber, and / or an exhaust system from the reaction processing chamber. Has an exhaust gas treatment section for treating the exhaust gas exhausted through, and the reaction treatment chamber and the exhaust system and / or the metal portion of the exhaust gas treatment section is formed of an aluminum alloy material, and the inner surface thereof is 1
A semiconductor manufacturing apparatus, which is obtained by planarizing to a surface roughness of 0 μm or less, forming an underlayer, and then performing a passivation treatment. 5. The underlayer is made of nickel phosphorus,
5. The semiconductor manufacturing according to claim 2, 3 or 4, wherein the passivation treatment is performed by forming a fluorine compound layer with a partial substance forming stainless steel or nickel on a stainless material or an underlayer. apparatus. 6. The semiconductor manufacturing apparatus according to claim 1, wherein the processing gas comprises a corrosive gas such as a chlorine-based gas or a halogen-based gas.