Method for manufacturing semiconductor substrate

A method for manufacturing a semiconductor substrate, comprising:

• performing carbonization treatment on a surface of a silicon substrate to form a silicon carbide layer;
• adding ions to the silicon substrate to form an embrittlement region in the silicon substrate;
• bonding the silicon substrate to a base substrate with insulating layers interposed between the silicon substrate and the base substrate;
• heating the silicon substrate and separating the silicon substrate at the embrittlement region to form a stacked layer of the silicon carbide layer and a silicon layer over the base substrate with the insulating layers interposed between the base substrate and the stacked layer;
• oxidizing the silicon layer to form a silicon oxide layer;
• and
• thinning the silicon oxide layer to form a stacked layer of the silicon carbide layer and a thinned silicon oxide layer.

A method for manufacturing a semiconductor substrate, comprising:

• performing carbonization treatment on a surface of a silicon substrate to form a silicon carbide layer;
• adding ions to the silicon substrate to form an embrittlement region in the silicon substrate;
• bonding the silicon substrate to a base substrate with insulating layers interposed between the silicon substrate and the base substrate;
• heating the silicon substrate and separating the silicon substrate at the embrittlement region to form a stacked layer of the silicon carbide layer and a silicon layer over the base substrate with the insulating layers interposed between the base substrate and the stacked layer;
• thinning the silicon layer to form a thinned silicon layer;
• and
• oxidizing the thinned silicon layer to form a stacked layer of the silicon carbide layer and a thinned silicon oxide layer after thinning the silicon layer.