In {TAIL ~ the case} of an n type device, {HEAD ~ Ph dopants} may be implanted 
In { TAIL ~ the case } of an n type device , { HEAD ~ Ph dopants } may be implanted
REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL