P-type 4h-sic single crystal and method for producing p-type 4h-sic single crystal

Abstract

The present invention provides a p-type 4H—SiC single crystal, which is doped with both aluminum and nitrogen, and has a nitrogen concentration of 2.0×10 19 /cm 3 or more.

What is claimed is: 
     
         1 . A p-type 4H—SiC single crystal, which is doped with both aluminum and nitrogen, and of which a nitrogen concentration is 2.0×10 19 /cm 3  or more and an aluminum concentration is 1.0×10 20 /cm 3  or more. 
     
     
         2 . The p-type 4H—SiC single crystal according to  claim 1 , wherein the aluminum concentration is 1.8×10 20 /cm 3  or more. 
     
     
         3 . The p-type 4H—SiC single crystal according to  claim 1 , wherein a stacking fault density is 50/cm or less. 
     
     
         4 . The p-type 4H—SiC single crystal according to  claim 1 , wherein a concentration of any element from the group consisting of phosphorus, arsenic, titanium, vanadium, chromium, copper, iron, and nickel is 2×10 15 /cm 3  or less. 
     
     
         5 . The p-type 4H—SiC single crystal according to  claim 1 , wherein a thickness is 1 mm or more. 
     
     
         6 . A method for producing a p-type 4H—SiC single crystal, comprising:
 a sublimation step of sublimating a nitrided aluminum raw material and a SiC raw material; and 
 a crystal-growth step of stacking a SiC single crystal, which is co-doped with aluminum and nitrogen, on one surface of a seed crystal. 
 
     
     
         7 . The method for producing a p-type 4H—SiC single crystal according to  claim 6 , wherein in the sublimation step, the nitrided aluminum raw material and the SiC raw material are disposed separately from each other, and are sublimated at different temperatures. 
     
     
         8 . The method for producing a p-type 4H—SiC single crystal according to  claim 6 , wherein the sublimation step and the crystal-growth step are performed under a nitrogen gas atmosphere. 
     
     
         9 . The method for producing a p-type 4H—SiC single crystal according to  claim 6 , further comprising a step of nitriding an aluminum raw material to prepare the nitrided aluminum raw material, before the sublimation step.