Silicon nitride film forming apparatus and film forming method

Abstract

The present invention is to provide a silicon nitride film forming apparatus and a forming method which makes possible the high reproducibility of film quality or film thickness. The silicon nitride film forming apparatus and forming method in which a heating element and a substrate are arranged in a vacuum vessel connected to a gas exhaust system and a gas supply system to deposit a silicon nitride film on the substrate surface by maintaining the heating element at a predetermined temperature and by decomposing and/or activating a raw material gas supplied from the gas supply system, comprises: an inner wall which is arranged in the vacuum vessel surrounding the heating element and the substrate so as to form a film formation space, a gas introduction means to introduce the raw material gas to the film forming space, and at least one of a heating means and a cooling means of the inner wall arranged to control the inner wall to a predetermined temperature.

1 . A silicon nitride film forming apparatus in which a heating element and a substrate are arranged in a vacuum vessel connected to a gas exhaust system and a gas supply system to deposit a silicon nitride film on said substrate surface by maintaining said heating element at a predetermined temperature and by decomposing and/or activating a raw material gas supplied from said gas supply system, comprising: 
 an inner wall which is arranged in said vacuum vessel surrounding said heating element and said substrate so as to form a film formation space,    a gas introduction means to introduce the raw material gas to said film forming space, and    at least one of a heating means and a cooling means of said inner wall arranged to control said inner wall to a predetermined temperature.    
     
     
         2 . The silicon nitride film forming apparatus according to  claim 1 , wherein said inner wall is connected to said vacuum vessel through a support portion and the temperature of said inner wall and said vacuum vessel can be independently controlled.  
     
     
         3 . The silicon nitride film forming apparatus according to  claim 1 , wherein said inner wall is composed of a first inner wall and a second inner wall.  
     
     
         4 . The silicon nitride film forming apparatus according to  claim 3 , wherein said first inner wall and said second inner wall are connected to each other and supported at the connection portion.  
     
     
         5 . The silicon nitride film forming apparatus according to  claim 1 , wherein the inside configuration of said inner wall is constructed so that each part of said inner wall receives nearly the same amount of heat radiation from said heating element.  
     
     
         6 . The silicon nitride film forming apparatus according to  claim 1 , wherein said cooling means of said inner wall is an annular cooling mechanism disposed at said connection portion.  
     
     
         7 . The silicon nitride film forming apparatus according to  claim 1 , wherein said gas introduction means is constructed so that the raw material gas is emitted toward the portion of said inner wall which faces said substrate surface to be processed.  
     
     
         8 . A silicon nitride film forming method in which a heating element and a substrate are arranged in a vacuum vessel connected to a gas exhaust system and a gas supply system to deposit a silicon nitride film on said substrate surface by maintaining said heating element at a predetermined temperature and by decomposing and/or activating a raw material gas supplied from said gas supply system, 
 wherein an inner wall is arranged in said vacuum vessel surrounding said heating element and said substrate so as to form a film formation space, said inner wall is controlled to a predetermined temperature, and the raw material gas is introduced into said film forming space to carry out the formation of the silicon nitride thin film.    
     
     
         9 . The silicon nitride film forming method according to  claim 8 , wherein the raw material gas is emitted toward the portion of said inner wall which faces said substrate surface to be processed and the pressure of said film formation space is set to 0.1-10 Pa.