SUPPORTING SUBSTRATE, BONDING SUBSTRATE, METHOD FOR MANUFACTURING SUPPORTING SUBSTRATE, AND METHOD FOR MANUFACTURING BONDING SUBSTRATE

摘要

Provided is a supporting substrate (30) to be bonded on a single crystalline wafer composed of a single crystalline body. The supporting substrate is provided with a silicon carbide polycrystalline substrate (10) composed of a silicon carbide polycrystalline body, and a coat layer (20) deposited on the silicon carbide polycrystalline substrate (10). The coat layer (20) is composed of silicon carbide or silicon and is in contact with the single crystalline wafer, and the arithmetic average roughness of the contact surface (22) of the coat layer (20) in contact with the single crystalline wafer is 1 nm or less.