Silicon carbide single-crystal substrate and method for manufacturing same

Abstract

A silicon carbide single-crystal substrate includes a first surface, a second surface opposite to the first surface, and a peripheral edge portion sandwiched between the first surface and the second surface, A plurality of grinding traces are formed in a surface of the peripheral edge portion. A chamfer width as a distance from an outermost peripheral end portion of the peripheral edge portion to one of the plurality of grinding traces which is located on an innermost peripheral side of the peripheral edge portion in a direction parallel to the first surface is not less than 50 μm and not more than 400 μm. Thereby, a silicon carbide single-crystal substrate capable of suppressing occurrence of a crack, and a method for manufacturing the same can be provided.

1 - 3 . (canceled) 
     
     
         4 . A method for manufacturing a silicon carbide single-crystal substrate, comprising the steps of:
 preparing a silicon carbide single crystal having a first surface, a second surface opposite to said first surface, and a peripheral edge portion sandwiched between said first surface and said second surface;   preparing a grindstone having diamond abrasive grains embedded in a binder, a hardness grade of said diamond abrasive grains and said binder in accordance with the Japanese Industrial Standards being L to N, a degree of concentration of said diamond abrasive grains being not less than 80 and not more than 150; and   polishing said peripheral edge portion using said grindstone.   
     
     
         5 . The method for manufacturing a silicon carbide single-crystal substrate according to  claim 4 , wherein said diamond abrasive grains have a grain size of #400 to #2500 in accordance with the Japanese Industrial Standards.