{TAIL ~ The trenches} are then filled with semiconductor material of {HEAD ~ a conductivity type} opposite that of the semiconductor body 
{ TAIL ~ The trenches } are then filled with semiconductor material of { HEAD ~ a conductivity type } opposite that of the semiconductor body
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH