A bonding surface of first semiconductor substrate 11 , and {HEAD ~ a bonding surface} of {TAIL ~ second semiconductor substrate} 12 are mirror finished to provide a surface roughness of below 500 Å each 
of
A bonding surface of first semiconductor substrate 11 , and { HEAD ~ a bonding surface } of { TAIL ~ second semiconductor substrate } 12 are mirror finished to provide a surface roughness of below 500 Å each
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH