{TAIL ~ An electrical insulation} is formed between the first region and {HEAD ~ the second region} of the semiconductor layer 
{ TAIL ~ An electrical insulation } is formed between the first region and { HEAD ~ the second region } of the semiconductor layer
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH