Semiconductor device having silicon oxide film

Abstract

A semiconductor device whose working life can be improved is obtained. This semiconductor device comprises a first conductive layer, a second conductive layer and a silicon oxide film, formed between the first and second conductive layers, containing chlorine introduced therein. Thus, the silicon oxide film is inhibited from formation of electron traps while a large number of holes are formed in an initial stage of electron injection into the silicon oxide film.

1 . A semiconductor device comprising: 
 a first conductive layer;    a second conductive layer; and    a silicon oxide film, formed between said first conductive layer and said second conductive layer, containing chlorine introduced therein, wherein:    nitrogen is introduced into said silicon oxide film in concentration of at least 1×10 20  atoms/cm 3  in addition to said chlorine;    the chlorine concentration in said silicon oxide film is at least 1×10 19  atoms/cm 3 ; and    the maximum chlorine concentration in said silicon oxide film is not more than 1×10 21  atoms/cm 3 .    
   
   
       2 - 4 . (canceled)  
   
   
       5 . The semiconductor device according to  claim 1 , wherein 
 the maximum value of the concentration profile of said chlorine introduced into said silicon oxide film is smaller than the concentration profile of said nitrogen introduced into said silicon oxide film.    
   
   
       6 . The semiconductor device according to  claim 1 , wherein 
 a position maximizing the concentration profile of said nitrogen introduced into said silicon oxide film is located closer to the interface between said silicon oxide film and said first conductive layer than a position maximizing the concentration profile of said chlorine introduced into said silicon oxide film.    
   
   
       7 . The semiconductor device according to  claim 6 , wherein 
 SiN is formed in the vicinity of the interface between said silicon oxide film and said first conductive layer.    
   
   
       8 . The semiconductor device according to  claim 6 , wherein 
 said position maximizing the concentration profile of said chlorine introduced into said silicon oxide film is located closer to the interface between said silicon oxide film and said first conductive layer than the central portion of said silicon oxide film along the thickness direction.    
   
   
       9 . The semiconductor device according to  claim 1 , wherein 
 a position maximizing the concentration profile of said nitrogen introduced into said silicon oxide film is located closer to the interface between said silicon oxide film and said second conductive layer than a position maximizing the concentration profile of said chlorine introduced into said silicon oxide film.    
   
   
       10 . The semiconductor device according to  claim 9 , wherein 
 SiN is formed in the vicinity of the interface between said silicon oxide film and said second conductive layer.    
   
   
       11 . The semiconductor device according to  claim 9 , wherein 
 said position maximizing the concentration profile of said chlorine introduced into said silicon oxide film is located closer to the interface between said silicon oxide film and said second conductive layer than the central portion of said silicon oxide film along the thickness direction.    
   
   
       12 - 20 . (canceled)