Surface cleaning method of semiconductor wafer heat treatment boat

Abstract

A surface cleaning method of a semiconductor wafer heat treatment boat that can prevent metallic contamination to semiconductor wafers and keep down a production time and manufacturing costs of semiconductor wafers by efficiently and easily removing metallic impurities in an oxide film on an SiC boat surface is provided. A surface cleaning method of a semiconductor wafer heat treatment boat according to an embodiment of the present invention is a surface cleaning method of a semiconductor wafer heat treatment boat whose surface is formed of SiC, includes oxidizing the surface of the heat treatment boat by thermal oxidation and etching a portion of the oxide film formed after oxidation is removed.

1 . A surface cleaning method of a semiconductor wafer heat treatment boat whose surface is made of silicon carbide (SiC), comprising;
 Oxidizing the surface of the semiconductor wafer heat treatment boat by thermal oxidation, and   Etching a portion of an oxide film formed after oxidation of the surface.   
     
     
         2 . The method according to  claim 1 , wherein an HF solution is used as an etchant for etching the portion of the oxide film. 
     
     
         3 . The method according to  claim 1 , wherein 10 nm or more of the oxide film is etched when the portion of the oxide film is etched. 
     
     
         4 . The method according to  claim 1 , wherein a treatment temperature of the thermal oxidation is 1100° C. or more and 1200° C. or less. 
     
     
         5 . The method according to  claim 1 , wherein the oxide film has a thickness of 60 nm or more and 300 nm or less. 
     
     
         6 . The method according to  claim 1 , wherein 50% or less of a thickness of the oxide film is etched when the portion of the oxide film is etched. 
     
     
         7 . The method according to  claim 1 , wherein the boat is formed of an Si-impregnated SiC base material with CVD-SiC deposited on the surface thereof. 
     
     
         8 . The method according to  claim 1 , wherein the semiconductor wafer is a silicon wafer.