The surface of {TAIL ~ the first semiconductor} {HEAD ~ substrate} 11 in composite substrate structure 10 is polished to have a thickness of, for example, about 100 μm and oxide film 16 is selectively formed as an etching resistant film on the surface of the resultant structure  
The surface of { TAIL ~ the first semiconductor } { HEAD ~ substrate } 11 in composite substrate structure 10 is polished to have a thickness of , for example , about 100 μm and oxide film 16 is selectively formed as an etching resistant film on the surface of the resultant structure
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH