Exhaust structure of film-forming apparatus, film-forming apparatus, and method for processing exhaust gas

Abstract

A film-forming apparatus 100 includes a processing chamber 11 , and TiCl 4 gas and NH 3 gas are supplied into the processing chamber 11 for forming a TiN film on a substrate W in the processing chamber 11 by CVD. The processing chamber 11 has a gas exhaust system 300 . The gas exhaust system 300 includes a gas exhaust pipe 51 for exhausting the exhaust gas in the processing chamber 11 , a trap mechanism 54 provided to the gas exhaust pipe 51 for trapping a by-product in the exhaust gas, and a heated reaction gas supply mechanism 60 for supplying a heated reaction gas into the exhaust gas. The heated reaction gas is adapted to react with a component in the exhaust gas to produce a by-product. Specifically, NH 3 gas is supplied by the heated reaction gas supply mechanism 60 as the heated reaction gas, and NH 4 Cl is produced as the by-product.

1 . A gas exhaust system of a film-forming apparatus for forming a film by CVD on a substrate placed in a processing chamber by supplying a processing gas into the processing chamber, the gas exhaust system of the film-forming apparatus comprising:
 a gas exhaust pipe connected to the processing chamber, for exhausting an exhaust gas in the processing chamber;   a trap mechanism provided to the gas exhaust pipe, for trapping a by-product in the exhaust gas; and   a heated reaction gas supply mechanism for supplying a heated reaction gas into the exhaust gas, the heated reaction gas adapted to react with a component in the exhaust gas to produce a by-product.   
   
   
       2 . The gas exhaust system of  claim 1 , wherein a TiN film is formed by CVD on the substrate placed in the processing chamber by supplying TiCl 4  gas and NH 3  gas as the processing gas into the processing chamber and, at the same time, NH 4 Cl is produced as a by-product by supplying NH 3  gas as the heated reaction gas from the heated reaction gas supply mechanism. 
   
   
       3 . The gas exhaust system of  claim 2 , wherein the NH 3  gas as the heated reaction gas is supplied while being heated at about 170° C. or higher. 
   
   
       4 . The gas exhaust system of  claim 1 , wherein the heated reaction gas supply mechanism supplies the heated reaction gas to an upstream side of the trap mechanism on the gas exhaust pipe via a pipe. 
   
   
       5 . The gas exhaust system of  claim 1 , wherein the heated reaction gas supply mechanism supplies the heated reaction gas to the trap mechanism via a pipe. 
   
   
       6 . The gas exhaust system of  claim 1 , wherein the heated reaction gas supply mechanism includes a reaction gas heating unit for heating a reaction gas, and the reaction gas heating unit has a heating chamber for heating the reaction gas therein and a coiled heating element disposed in the heating chamber. 
   
   
       7 . The gas exhaust system of  claim 1 , wherein a bypass pipe for exhausting the processing gas without passing through the processing chamber is connected to an inlet side of the processing chamber. 
   
   
       8 . The gas exhaust system of  claim 7 , further comprising a heating/mixing chamber for heating and mixing the processing gas flowing through the bypass pipe and the heated reaction gas supplied from the heated reaction gas supply mechanism. 
   
   
       9 . A film-forming apparatus for forming a film on a substrate, comprising:
 a processing chamber in which a substrate is placed;   a processing gas supply mechanism for supplying a processing gas into the processing chamber where the substrate is placed;   a unit for causing a film forming reaction on the substrate by imparting energy to the processing gas; and   a gas exhaust system for exhausting an exhaust gas in the processing chamber and processing the exhaust gas,   wherein the gas exhaust system includes:   a gas exhaust pipe for exhausting the exhaust gas in the processing chamber;   a trap mechanism provided to the exhaust pipe, for trapping a by-product in the exhaust gas; and   a heated reaction gas supply mechanism for supplying a heated reaction gas into the exhaust gas, the heated reaction gas adapted to react with a component in the exhaust gas to produce a by-product.   
   
   
       10 . The film-forming apparatus of  claim 9 , wherein the processing gas supply mechanism is provided with a unit for heating the substrate placed in the processing chamber to form a TiN film by causing a film forming reaction on the substrate by supplying TiCl 4  gas and NH 3  gas as the processing gas into the processing chamber, and NH 4 Cl is produced as a by-product by supplying NH 3  gas as the heated reaction gas from the heated reaction gas supply mechanism. 
   
   
       11 . A method for processing an exhaust gas in a film-forming apparatus for forming a film by CVD on a substrate placed in a processing chamber by supplying a processing gas into the processing chamber, the method comprising:
 exhausting the exhaust gas in the processing chamber through a gas exhaust pipe connected to the processing chamber;   forming a by-product by supplying a heated reaction gas into the exhaust gas flowing in the gas exhaust pipe, the heated reaction gas adapted to react with a component in the exhaust gas; and   trapping the by-product by a trap mechanism.   
   
   
       12 . The method of  claim 11 , wherein a TiN film is formed by CVD on a substrate placed in the processing chamber by supplying TiCl 4  gas and NH 3  gas as the processing gas into the processing chamber and, at the same time, NH 4 Cl is produced as the by-product by supplying NH 3  gas as the heated reaction gas, which reacts with TiCl 4  in the exhaust gas, into the exhaust gas flowing in the gas exhaust pipe and, then, the produced NH 4 Cl as the by-product is trapped by the trap mechanism. 
   
   
       13 . A computer-readable storage medium storing software for executing a control program in a computer, wherein, when executed, the control program controls a method for processing an exhaust gas in a film-forming apparatus for forming a film by CVD on a substrate placed in a processing chamber by supplying a processing gas into the processing chamber, the method comprising:
 exhausting an exhaust gas in the processing chamber through a gas exhaust pipe connected to the processing chamber;   forming a by-product by supplying a heated reaction gas into the exhaust gas flowing in the gas exhaust pipe, the heated reaction gas adapted to react with a component in the exhaust gas; and   trapping the by-product by a trap mechanism.   
   
   
       14 . A computer program for, when executed on a computer, controlling a film-forming apparatus to perform a method for processing an exhaust gas in the film-forming apparatus for forming a film by CVD on a substrate placed in a processing chamber by supplying a processing gas into the processing chamber, the method comprising:
 exhausting an exhaust gas in the processing chamber through a gas exhaust pipe connected to the processing chamber;   forming a by-product by supplying a heated reaction gas into the exhaust gas flowing in the gas exhaust pipe, the heated reaction gas adapted to react with a component in the exhaust gas; and   trapping the by-product by a trap mechanism.