Semiconductor device and method for manufacturing the same

Abstract

A semiconductor device according to embodiments includes a p-type SiC region, a gate insulating film disposed on the p-type SiC region, and a gate electrode disposed on the gate insulating film and including a p-type impurity and 3 C-SiC.

What is claimed is: 
     
         1 . A semiconductor device, comprising:
 a p-type SiC region;   a gate electrode including a p-type impurity and 3C-SiC; and   a gate insulating film disposed between the p-type SiC region and the gate electrode.   
     
     
         2 . The device according to  claim 1 , wherein
 the gate electrode includes the p-type impurity and the 3C-SiC at least in a region contacting the gate insulating film.   
     
     
         3 . The device according to  claim 1 , wherein
 the p-type SiC region is 4H-SiC.   
     
     
         4 . The device according to  claim 1 , wherein
 the p-type impurity is aluminum (Al), gallium (Ga), or indium (In).   
     
     
         5 . The device according to  claim 1 , wherein
 a concentration of the p-type impurity in the gate electrode is equal to or more than 1×10 19  cm −3 .   
     
     
         6 . The device according to  claim 1 , wherein
 a concentration of a p-type impurity in the p-type SiC region is equal to or less than 1×10 10  cm −3 .   
     
     
         7 . The device according to  claim 1 , wherein
 the volume of the 3C-SiC in the gate electrode is larger than the volume of 4H-SiC in the gate electrode.   
     
     
         8 . The device according to  claim 1 , wherein
 the gate insulating film is a silicon oxide film.   
     
     
         9 . A method for manufacturing a semiconductor device, comprising:
 forming a gate insulating film on a p-type SiC region; and   forming, on the gate insulating film, a gate electrode including a p-type impurity and 3C-SiC at a temperature of equal to or less than 1,200° C.   
     
     
         10 . The method according to  claim 9 , wherein
 the forming of the gate electrode includes depositing a 3C-SiC layer including the p-type impurity by chemical vapor deposition (CVD) at a temperature of equal to or less than 1,200° C.   
     
     
         11 . The method according to  claim 9 , wherein
 the forming of the gate electrode includes depositing a silicon film including the p-type impurity and performing heat treatment to carbonize the silicon film at a temperature of equal to or less than 1,200° C.   
     
     
         12 . The method according to  claim 11 , wherein
 the heat treatment is performed in an atmosphere including ethane (C 2 H 6 ), ethylene (C 2 H 6 ), or acetylene (C 2 H 2 ).   
     
     
         13 . The method according to  claim 9 , wherein
 the p-type impurity is aluminum (Al), gallium (Ga), or indium (In).