After distributing {HEAD ~ a nonmetal element} in a region in the vicinity of a surface portion of {TAIL ~ a semiconductor layer}, a metal film is deposited on the semiconductor layer 
After distributing { HEAD ~ a nonmetal element } in a region in the vicinity of a surface portion of { TAIL ~ a semiconductor layer } , a metal film is deposited on the semiconductor layer
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH