JP2005093526A - Semiconductor manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor manufacturing apparatus which can collect efficiently predetermined components in a collection means. <P>SOLUTION: The semiconductor manufacturing apparatus comprises a chamber 1, a processing means which introduces treatment gas in the chamber 1 and performs treatment process of a semiconductor substrate 7, and a discharge means for exhausting gas in the chamber 1. The discharge means comprises a dry scroll pump 2 as the discharge pump; and a gas discharge trap 5 (5a, 5b) as the collection means which is connected with the chamber 1 through the dry scroll pump 2, and collects predetermined components (e.g. phosphorus or the like) contained in the gas exhausted by the gas discharge means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor manufacturing apparatus, and more particularly to a semiconductor manufacturing apparatus provided with exhaust means for exhausting a gas in a chamber.

When processing the semiconductor device in the chamber, for example, a processing gas such as phosphine (PH ₃ ) which is a phosphorus-based gas is used. Here, the processing gas that has not contributed to the processing of the semiconductor device (including the unprocessed gas that has not been decomposed and the product that has been generated by the decomposition of the processing gas) is exhausted out of the chamber by the exhaust means. The

  Here, in an exhaust pump or the like, components contained in the processing gas may be solidified and deposited, thereby affecting the function of the exhaust means, maintainability, and the like.

  On the other hand, as a conventional example of a semiconductor manufacturing apparatus provided with the above-described exhaust means, for example, JP-A-6-224134 (conventional example 1), JP-A-8-83773 (conventional example 2), and Examples include those described in Kaihei 10-113532 (conventional example 3).

  In Conventional Example 1, phosphorus-based deposits deposited in the passage from the growth pipe for crystal growth to the exhaust gas pipe are heated and volatilized by the heating and volatilizing means, and the volatilized deposits are precipitated and trapped. A vapor phase crystal growth apparatus provided with a collecting means for collecting is disclosed. In addition, a vapor phase crystal growth apparatus provided with a heating means for changing yellow phosphorus contained in the deposit into red phosphorus having a high ignition point is disclosed instead of the heating volatilization means.

  In Conventional Example 2, a thin film forming apparatus is disclosed in which a cold trap means maintained at approximately −60 ° C. or less is provided between the reaction furnace and the gas discharge means.

  In Conventional Example 3, the inside of the case that cools the exhaust gas is divided into a plurality of cooling chambers by partition plates, and exhaust gas is provided by providing through holes in these partition plates and a rectifying plate inside the cooling chamber. An apparatus for removing harmful substances with improved cooling capacity is disclosed.

  FIG. 2 is a diagram showing a configuration of a semiconductor manufacturing apparatus described in Japanese Patent Laid-Open No. 2003-45861 (conventional example 4).

  As shown in FIG. 2, the semiconductor manufacturing apparatus disclosed in Conventional Example 4 includes a reaction tube 101 for processing a semiconductor substrate, and a gas introduction system (introducing a source gas connected to the reaction tube 101 ( And an exhaust system 103 for discharging the raw material gas connected to the reaction tube 101.

  In FIG. 2, the exhaust gas is conveyed in the direction of the arrow. The exhaust system 103 includes two exhaust systems 103a and 103b. For each of the exhaust systems 103a and 103b, the opening and closing valves 106a and 106b and the exhaust traps 105a and 105b are connected by an exhaust pipe 106 from the upstream side. . The two exhaust systems are joined by a switching valve 106 c and connected by an exhaust pipe 106 so as to reach the vacuum pump 102. With this configuration, exhaust gas is released to the outside.

  The exhaust traps 105a and 105b have couplers 108 (108a, 108b, 108c, and 108d) on both sides so that connection and disconnection with the front and rear exhaust pipes are easy.

As described above, this semiconductor manufacturing apparatus has a structure intended to deposit specific by-products that have not contributed to the processing of the semiconductor substrate on the exhaust traps 105a and 105b. For example, when phosphine is used as the source gas, the water-cooled exhaust traps 105a and 105b function as a phosphorus trap device.
JP-A-6-224134 JP-A-8-83773 JP-A-10-113532 JP 2003-45861 A

  However, the semiconductor manufacturing apparatus as described above has the following problems.

  In recent years, from the viewpoint of improving throughput and the like, semiconductor manufacturing apparatuses have become larger, and along with this, exhaust pumps are also becoming larger. As a result, the gas flow rate in the exhaust pipe tends to increase.

  On the other hand, in the conventional semiconductor manufacturing apparatus, the function of depositing a predetermined component in the exhaust gas in the trap may not be sufficient while the exhaust gas passes through the exhaust trap. As a result, the components to be collected in the exhaust trap are also included in the exhaust gas after passing through the exhaust trap, and the product accumulates in a wide range of exhaust pipes downstream of the exhaust trap. It becomes. In this case, it is necessary to stop the apparatus for a long time when removing the deposit, and there is a problem that the throughput is not improved.

  In the structure shown in FIG. 2, by providing two exhaust pipes, even when one system is removed for maintenance, the apparatus is continuously operated by using the other exhaust pipe. be able to. However, when the product accumulates in a wide range downstream from the exhaust trap as described above, the function may not be exhibited.

  From a viewpoint different from the above, a method of lowering the cooling temperature by the cooling means of the exhaust trap can be considered, but in this case, an expensive refrigerant such as liquid nitrogen is required, resulting in an increase in cost.

  From another point of view, a method of reducing the exhaust gas flow velocity by increasing the diameter of the exhaust pipe is conceivable. In this case, however, the thermal conductivity in the pipe is reduced, resulting in a decrease in gas cooling efficiency. To do.

  This invention is made | formed in view of the above problems, and the objective of this invention is to provide the semiconductor manufacturing apparatus which can collect a predetermined component efficiently in this collection means. .

  In one aspect, a semiconductor manufacturing apparatus according to the present invention includes a chamber, a processing unit that introduces a processing gas into the chamber to perform a semiconductor substrate processing process, and an exhaust unit that exhausts the gas in the chamber. The exhaust means includes an exhaust pump and a collection means that is connected to the chamber via the exhaust pump and collects a predetermined component contained in the gas exhausted by the exhaust means.

  Thereby, since the flow velocity of the exhaust gas in the collection means can be reduced, a predetermined component can be efficiently collected in the collection means.

  It is preferable to connect a plurality of collecting means in parallel.

  Thereby, the flow rate of the exhaust gas in the collection means can be further reduced.

  The collecting means preferably has a cooling means for cooling the exhaust gas from the chamber.

  Thereby, since the predetermined component in the exhaust gas is easily solidified in the collecting means, the predetermined component can be efficiently collected in the collecting means.

  The exhaust means preferably further includes a heating means between the chamber and the collection means.

  Thereby, since the predetermined component in the exhaust gas is hardly solidified between the chamber and the collecting means, the predetermined component can be efficiently collected by the collecting means.

  The semiconductor manufacturing apparatus described above is preferably used for a semiconductor substrate thin film formation process or crystal growth process.

  In the thin film formation process or crystal growth process of the semiconductor substrate, a relatively large amount of processing gas that does not contribute to the processing of the semiconductor substrate is generated, so that the effect of efficiently collecting a predetermined component in the collecting means is great.

  As said process gas, what contains phosphorus can be considered.

  Phosphorous by-products must be handled with particular care. On the other hand, by using the semiconductor manufacturing apparatus, the by-products and the like can be collected in a concentrated manner in the collecting means, so that handling becomes easy.

  In another aspect, the semiconductor manufacturing apparatus according to the present invention includes a chamber, processing means for introducing a processing gas into the chamber to perform a processing process on the semiconductor substrate, an exhaust pump for exhausting the gas in the chamber, and an exhaust pump. And a collecting means for collecting a predetermined component contained in the gas exhausted by the exhaust pump, the pressure being higher than the pressure in the chamber during processing by the processing means.

  Thereby, since the flow velocity of the exhaust gas in the collection means can be reduced, the predetermined component can be efficiently collected in the collection means.

  According to the present invention, the flow rate of the exhaust gas can be reduced in the collecting means included in the exhaust path of the semiconductor manufacturing apparatus, and a predetermined component can be efficiently collected in the collecting means.

  An embodiment of a semiconductor manufacturing apparatus according to the present invention will be described below with reference to FIG.

  FIG. 1 is a diagram showing a configuration of a semiconductor manufacturing apparatus according to the present embodiment.

  As shown in FIG. 1, the semiconductor manufacturing apparatus according to the present embodiment includes a chamber 1, processing means (not shown) for introducing a processing gas into the chamber 1 and performing a processing process on the semiconductor substrate 7, and a chamber 1 is provided, and the exhaust means is connected to the chamber 1 via the dry scroll pump 2 and the dry scroll pump 2 and is included in the gas exhausted by the exhaust means. And an exhaust trap 5 (5a, 5b) as a collecting means for collecting a predetermined component (for example, phosphorus).

  In FIG. 1, the process gas is conveyed in the direction of the arrow. Note that the processing gas (exhaust gas) on the downstream side of the chamber 1 includes an untreated gas that has not been decomposed and a product that is generated by the decomposition of the processing gas.

  The chamber 1, the dry scroll pump 2, and the exhaust trap 5 (5a, 5b) are connected by an exhaust pipe 6. The exhaust pipe 6 branches into two systems between the dry scroll pump 2 and the exhaust trap 5 (5a, 5b), and joins again on the downstream side of the exhaust trap 5 (5a, 5b). The exhaust pipe 6 communicates with the outside through a detoxification tower 4 that detoxifies unreacted processing gas.

  In addition, when switching valves are installed at the branch points and the merge points, and maintenance of one of the exhaust traps 5a and 5b (deposit removal, etc.) is performed, only the exhaust system including the other exhaust trap is used. It is good also as a structure which can operate an apparatus continuously.

  In the chamber 1, a semiconductor substrate is processed (for example, etching, thin film formation, etc.). At this time, the inside of the chamber 1 is in a reduced pressure state whose pressure is lower than the atmospheric pressure. On the other hand, the pressure in the exhaust pipe 6 on the downstream side of the dry scroll pump 2 becomes a pressure close to atmospheric pressure. Therefore, the flow rate of the exhaust gas is reduced on the downstream side of the dry scroll pump 2 compared to the upstream side.

  Here, the exhaust gas flow rate in the exhaust trap 5 can be reduced by installing the exhaust trap 5 on the downstream side of the dry scroll pump 2. As a result, it is possible to efficiently collect a predetermined component in the exhaust trap 5.

  In FIG. 1, a plurality (two) of exhaust traps 5 (5 a, 5 b) are connected in parallel to the dry scroll pump 2.

  By providing two exhaust traps 5 in parallel, the flow rate of the exhaust gas in the exhaust trap 5 can be halved compared to the case of one exhaust trap.

  A plurality of dry scroll pumps may be used, and the exhaust trap 5 (5a, 5b) may be connected in parallel to the chamber 1 via separate dry scroll pumps.

  In FIG. 1, the exhaust traps 5 a and 5 b each have a water cooling pipe 9 as a cooling means for cooling exhaust gas from the chamber 1.

  Thereby, the predetermined components in the exhaust gas are easily solidified in the exhaust traps 5a and 5b, so that the predetermined components can be efficiently collected in the exhaust traps 5a and 5b.

  In FIG. 1, the exhaust means includes a pipe heater 8 as a heating means between a chamber 1 and an exhaust trap 5 (5a, 5b).

  This makes it difficult for the predetermined components in the exhaust gas to solidify until the exhaust gas reaches the exhaust traps 5a and 5b from the chamber 1, and therefore the predetermined components are efficiently collected in the exhaust traps 5a and 5b. be able to.

  The configuration of the semiconductor manufacturing apparatus described above can be applied to any apparatus used for manufacturing a semiconductor device, but is particularly preferably used for a thin film formation process or a crystal growth process of a semiconductor substrate.

  In the semiconductor substrate thin film formation process or crystal growth process, a relatively large amount of processing gas is generated that does not contribute to the processing of the semiconductor substrate, so that the effect of efficiently collecting predetermined components in the exhaust trap 5 is great.

  As said process gas, what contains phosphorus can be considered.

  Phosphorous by-products must be handled with particular care. On the other hand, by using the semiconductor manufacturing apparatus, the by-products and the like can be collected in the exhaust trap 5 in a concentrated manner, so that handling becomes easy.

  In other words, the configuration of the semiconductor manufacturing apparatus described above is as follows. That is, the semiconductor manufacturing apparatus according to the present embodiment includes a chamber 1, a processing means (not shown) for introducing a processing gas into the chamber 1 to perform a semiconductor substrate processing process, and exhausting the gas in the chamber 1. The dry scroll pump 2 (exhaust pump) and a gas exhaust path by the dry scroll pump 2 are set to a pressure higher than the pressure in the chamber 1 during processing by the processing means, and are exhausted by the dry scroll pump 2. Exhaust traps 5a and 5b (collecting means) for collecting predetermined components (for example, phosphorus) contained in the gas are provided.

  Hereinafter, a case where the semiconductor manufacturing apparatus is actually operated will be described more specifically with respect to the above-described contents.

In this embodiment, as an example of the processing gas, a source gas containing phosphine (PH ₃ ) and trimethylindium (TMIn) is mixed with a carrier gas containing hydrogen (H ₂ ). Use things. This processing gas is introduced into the chamber 1 and supplied to an indium phosphide (InP) wafer as an example of the semiconductor substrate 7 placed in the chamber 1. This wafer is heated to, for example, about 500 ° C. or more and 800 ° C. or less, and the source gas supplied onto the wafer is thermally decomposed, and indium phosphide is grown on the wafer.

  Thereafter, phosphorus and indium (heated product), which were thermally decomposed but did not contribute to the crystal growth, were dry-scrolled from the lower portion of the chamber 1 together with unreacted source gas and carrier gas that were not thermally decomposed. The pump 2 is evacuated at high speed and reaches the exhaust traps 5a and 5b through the exhaust pipe 6. In addition, as a ratio contained in the heating product, phosphorus is larger than indium.

  At this time, on the upstream side of the dry scroll pump 2, the flow rate of the exhaust gas is high, and the exhaust pipe 6 between the chamber 1 and the dry scroll pump 2 is constantly heated to about 60 ° C. or more and 80 ° C. or less by the pipe heater 8. Therefore, phosphorus and indium (heated product) contained in the exhaust gas reach the dry scroll pump 2 without being rapidly cooled.

  The pressure of the exhaust gas that has passed through the dry scroll pump 2 is converted from the reduced pressure state to the atmospheric pressure, and the flow velocity is rapidly reduced. Further, between the dry scroll pump 2 and the trap 5, the exhaust pipe 6 branches into two systems having the same exhaust resistance. This further reduces the gas flow rate.

  Here, due to the heat generated by the dry scroll pump 2 itself, the temperature of the pump is kept at about 60 ° C. or more and 80 ° C. or less, and the exhaust pipe 6 between the dry scroll pump 2 and the traps 5a and 5b is also The pipe heater 8 is heated to about 60 ° C. or more and 80 ° C. or less. Thereby, the exhaust gas containing phosphorus and indium (heated product) reaches the exhaust traps 5a and 5b without being rapidly cooled.

  A water cooling pipe 9 is passed through the exhaust traps 5a and 5b, and the inside of the trap is always cooled to a temperature of about 20 ° C. The exhaust gas containing phosphorus and indium (heated product) that has reached the exhaust traps 5a and 5b is sufficiently cooled while passing through the exhaust traps 5a and 5b. System products and the like can be solidified and deposited in the exhaust traps 5a and 5b.

  In the above apparatus configuration, the gas flow rate in the exhaust traps 5a and 5b (volume is about 8 liters) can be suppressed to about 25 liters / minute or less, and the phosphorus-based product is solidified only in the exhaust traps 5a and 5b. It is possible to prevent the phosphorus-based product from being deposited in the exhaust pipe 6 on the downstream side of the exhaust traps 5a and 5b.

In the present embodiment, phosphine is used as a source gas, but other gases such as tertiary butylphosphine (TBP; Tertiary Butyl PH ₃ ) or trimethylphosphine (TMP; Trimethyl PH ₃ ) are used. The same effect can be expected.

  Although the embodiments of the present invention have been described above, the embodiments disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is the figure which showed the structure of the semiconductor manufacturing apparatus which concerns on one embodiment of this invention. It is the figure which showed an example of the structure of the conventional semiconductor manufacturing apparatus.

Explanation of symbols

  1 chamber, 2 dry scroll pump, 4 abatement tower, 5a, 5b, 105a, 105b exhaust trap, 6,106 exhaust piping, 106a, 106b open / close valve, 106c switching valve, 7 semiconductor substrate, 8 piping heater, 9 cooling piping , 102 vacuum pump, 108a-108d coupler.

Claims (7)

A chamber;
Processing means for introducing a processing gas into the chamber to perform a semiconductor substrate processing process;
An exhaust means for exhausting the gas in the chamber,
The evacuation unit includes an evacuation pump and a collection unit that is connected to the chamber via the evacuation pump and collects a predetermined component contained in a gas exhausted by the evacuation unit. .   The semiconductor manufacturing apparatus according to claim 1, wherein a plurality of the collecting means are connected in parallel.   The semiconductor manufacturing apparatus according to claim 1, wherein the collection unit includes a cooling unit that cools an exhaust gas from the chamber.   The semiconductor manufacturing apparatus according to claim 1, wherein the exhaust unit further includes a heating unit between the chamber and the collecting unit.   The semiconductor manufacturing apparatus according to claim 1, wherein the semiconductor manufacturing apparatus is used for a thin film formation process or a crystal growth process of the semiconductor substrate.   The semiconductor manufacturing apparatus according to claim 1, wherein the processing gas contains phosphorus. A chamber;
Processing means for introducing a processing gas into the chamber to perform a semiconductor substrate processing process;
An exhaust pump for exhausting the gas in the chamber;
It is provided in the exhaust path of the gas by the exhaust pump, has a pressure higher than the pressure in the chamber at the time of processing by the processing means, and collects a predetermined component contained in the gas exhausted by the exhaust pump A semiconductor manufacturing apparatus comprising a collecting means.

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