JP2005353791A - Semiconductor production device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor production device preventing the load increase of exhaust-gas treatment equipment with the increase of the quantity of a reaction gas used and improving the capture capacity of a cold trap. <P>SOLUTION: The semiconductor production device has a reaction chamber 2 having a fitted gas introducing pipe 1. The eaction gas is exhausted through gas exhausting piping 14 from a gas exhaust port 3, and made harmless by the exhaust-gas treatment equipment 13 and discharged to the atmospheric air. A vacuum pump 5 for exhausting the reaction chamber 2 is arranged between the reaction chamber 2 and the exhaust-gas treatment equipment 13. The cold traps 6, 7, 8 and 9 cooling, solidifying and capturing the reaction gas after a film formation and cooling devices 10 and 11 for cooling the cold traps are arranged at the rear of the vacuum pump 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a semiconductor manufacturing apparatus including a cold trap that cools and solidifies a reaction gas after film formation.

  The configuration of a conventional MOCVD apparatus is shown in FIG.

Conventionally, in a semiconductor vapor deposition apparatus, in particular, a metal organic chemical vapor deposition apparatus (hereinafter referred to as MOCVD apparatus), a mixed gas such as an organometallic compound, PH ₃ , AsH ₃ or the like supplied from a gas introduction pipe 1 to a reaction chamber 2 is used. A film is formed on the substrate accommodated in the reaction chamber 1 by a chemical reaction thermally or by plasma.

  The reaction gas after film formation is exhausted from the gas exhaust port 3 through the gas exhaust pipe 14, detoxified by the exhaust gas treatment device 13, and then released into the atmosphere.

  A vacuum pump 5 for depressurizing the reaction chamber is disposed between the reaction chamber 2 and the exhaust gas treatment device 13, and a cooling medium fed by a water supply hose 12 from the cooling device A 10 is disposed behind the vacuum pump 5. A cooled cold trap A6 is installed. Valves 4 are attached before and after the vacuum pump 5 and the cold trap A6 in order to perform replacement easily and safely. The cold trap A6 reduces the load of the detoxification treatment of the exhaust gas treatment device 13 by solidifying and collecting the reaction gas.

As a method of collecting such a reactive gas, a method of trapping and collecting it by wrapping it in hydraulic oil of a vacuum pump (see, for example, Patent Document 1) or a method of collecting a gas by attaching a cold trap upstream from the vacuum pump ( For example, see Patent Document 2).
Japanese Patent Laid-Open No. 7-24250 JP-A-8-83773

  However, the MOCVD apparatus has been required to process a large number of sheets, and there is a tendency that the flow rate of the reaction gas increases as the reaction chamber becomes larger. Even in the cold trap that has compensated for the reduction in the load of the detoxification treatment of the exhaust gas treatment device, it has been necessary to improve the collection capacity in response to the increase in the flow rate of the reaction gas.

  In order to solve the above-mentioned problems, the semiconductor manufacturing apparatus of the present invention has a vacuum pump and an exhaust gas treatment device, and can adjust the temperature at which the reaction gas is cooled and solidified and collected between the vacuum pump and the exhaust gas treatment device. A plurality of such cold traps are arranged in series.

  In another semiconductor manufacturing apparatus of the present invention, there are two or more exhaust paths between the vacuum pump and the exhaust gas treatment apparatus, and a plurality of the cold traps are connected to each of the two or more exhaust paths. It is characterized by being.

  A plurality of the cold traps are arbitrarily divided into a plurality of groups, and in each group, the temperature of the reaction gas exhausted from the vacuum pump is lowered by 10 ° C. or more, and each cold trap is controlled at a different set temperature. preferable.

  These semiconductor manufacturing apparatuses have a reaction chamber, a substrate heating mechanism, and a mechanism for introducing a gas into the reaction chamber. The substrate is installed in the reaction chamber, and the gas is heated while the substrate is heated by the substrate heating mechanism. It is preferable to carry out film deposition on the substrate by introducing a reactive gas from the introduction mechanism.

  The present invention has the above-described configuration, can collect gas evenly in a plurality of cold traps, and can reduce the load of the detoxification process of the exhaust gas treatment apparatus. Moreover, the maintenance work time and maintenance cost of the cold trap and the exhaust gas treatment device can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing the configuration of an MOCVD apparatus according to an embodiment of the present invention.

The reaction chamber 2 is supplied with a mixture of an organic metal gas such as TMA or TMG and a gas such as PH ₃ , AsH _3, or SiH ₄ from the gas introduction pipe 1. In the reaction chamber 2, a thin film such as GaAs or GaInP is formed on the substrate by MOCVD. At this time, a thin film is formed while the substrate is heated by a substrate heating mechanism (not shown) such as a heater. The reaction gas is exhausted from the gas exhaust port 3 through the gas exhaust pipe 14, detoxified by the exhaust gas treatment device 13, and released to the atmosphere.

  A vacuum pump 5 for evacuating the reaction chamber 2 is disposed between the reaction chamber 2 and the exhaust gas treatment device 13. Behind the vacuum pump 5, cold traps 6, 7, 8, 9 for cooling and solidifying and collecting the reaction gas after film formation and cooling devices 10 and 11 for cooling the cold trap are arranged. Yes.

  The cooling device 10 is configured to be able to send a cooling medium such as ethylene glycol having a temperature controlled through the hose 12 to the cold traps 6 and 7, and the cooling device 11 to the cold traps 8 and 9, respectively.

  The cooling devices 10 and 11 take into account the state of gas collection in the cold traps 6, 7, 8, 9, and the cooling medium is sent to the cold traps 6, 7, 8, 9 for which the collection capability is to be increased. The set temperature of the apparatus can be arbitrarily changed within a range of −5 ° C. to 50 ° C. with respect to the set value. Thereby, it can collect equally in all the cold traps.

  In addition, when the cold traps 6 and 8 provided at the beginning are used and the collecting ability of the cold traps 6 and 8 is lowered, the valve 4 is connected to the cold traps 7 and 9 installed in parallel. Open and close to switch. After that, by replacing the system of the cold traps 6 and 8 that have caused a decrease in the collection capacity with a new cold trap, production can be continuously performed without stopping the equipment.

  Moreover, according to this Embodiment, it is also possible to use it in the form which considered the gas collection state of each cold trap. The details will be described below with reference to FIG.

A reaction gas obtained by mixing an organic metal gas such as TMG, TMA, or TMI with PH ₃ , AsH ₃ , SiH _4, or the like is supplied to the reaction chamber 2 from the gas introduction pipe 1. A thin film of GaAs, GaInP or the like is formed on the GaAs substrate housed in the reaction chamber 2 and heated to a high temperature by MOCVD.

  At this time, among the reaction gas exhausted from the gas exhaust port 3, in particular, the phosphorus-based gas and its product are collected by a cold trap before passing through the exhaust gas treatment device 13. As a result, the exhaust gas treatment device 13 can reduce the load of the detoxification treatment.

  At this time, the set temperature of each cooling device is arbitrarily changed in consideration of the collection state of each cold trap. In the initial stage of use, only one system of cold traps installed in parallel with two systems is used to collect phosphorus-based gas and products. At the beginning of cold trap use, set the temperature of the cooling device for the cold trap installed on the vacuum pump side to 20 ° C or higher with respect to the temperature of the reaction gas exhausted from the vacuum pump. The cooling device for the cold trap on the side is also set below that temperature.

  Thereby, the collection capability of the cold trap on the vacuum pump side is enhanced, and the reaction gas is collected. Since the trapping capacity of the cold trap on the vacuum pump side will be reduced after a certain period of use, the set temperature is lowered and changed within the range of 10 ° C to 20 ° C with respect to the temperature of the reaction gas exhausted from the vacuum pump. At the same time, the temperature of the cooling device for the cold trap on the exhaust gas treatment device is set to 20 ° C. or higher with respect to the temperature of the reaction gas exhausted from the vacuum pump. Increases the ability to collect cold traps.

  As described above, according to the present embodiment, when the trapping capacities of both cold traps are reduced, the cold pump on the vacuum pump side from the valve downstream of the cold trap on the exhaust gas treatment apparatus side of the remaining one system installed in two systems in parallel. We opened the trap upstream valve in order, and closed the valve of the cold trap of the exhaust system used so far in the reverse order of the previous work in order, and after switching, explained above By collecting gas by the same method, the maintenance efficiency of the apparatus can be increased and gas can be collected reliably, so that the maintenance cycle of the exhaust gas treatment apparatus can be improved and the life can be extended.

  In the present embodiment, the MOCVD apparatus has been described as an example. However, the same effect can be obtained when the present invention is applied to another CVD apparatus or an apparatus using a gas that requires detoxification, such as a dry etching apparatus.

The semiconductor manufacturing apparatus of the present invention is useful as a compound semiconductor vapor phase growth apparatus that uses a liquid gas that is highly ignitable or corrosive such as PH ₃ as a reaction gas.

Configuration of MOCVD apparatus in an embodiment of the present invention Configuration diagram of conventional MOCVD equipment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas introduction pipe 2 Reaction chamber 3 Gas exhaust port 4 Valve 5 Vacuum pump 6 Cold trap A
7 Cold Trap B
8 Cold Trap C
9 Cold Trap D
10 Cooling device A
11 Cooling device B
12 Water supply hose 13 Exhaust gas treatment device 14 Gas exhaust pipe

Claims (4)

A plurality of cold traps, each having a vacuum pump and an exhaust gas treatment device and capable of adjusting the temperature for cooling and solidifying and collecting the reaction gas between the vacuum pump and the exhaust gas treatment device, are arranged in series. Semiconductor manufacturing equipment. A semiconductor manufacturing apparatus having two or more exhaust paths between the vacuum pump and the exhaust gas treatment apparatus, wherein a plurality of the cold traps are connected to each of the two or more exhaust paths. A plurality of the cold traps are arbitrarily divided into a plurality of groups, and in each group, the temperature of the reaction gas exhausted from the vacuum pump is lowered by 10 ° C. or more to control the temperature of each cold trap at a different set temperature. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the semiconductor manufacturing apparatus is characterized. The semiconductor manufacturing apparatus has a reaction chamber, a substrate heating mechanism, and a mechanism for introducing gas into the reaction chamber,
2. A film is deposited on the substrate by placing a substrate in the reaction chamber, introducing a reactive gas from the gas introduction mechanism while heating the substrate by the substrate heating mechanism. 4. The semiconductor manufacturing apparatus according to any one of 3 above.

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