An emitter is in a contacting relationship with the first portion of the intrinsic base layer, and an extrinsic base layer is in a contacting relationship with {HEAD ~ the second portion} of {TAIL ~ the intrinsic base layer} 
of
An emitter is in a contacting relationship with the first portion of the intrinsic base layer , and an extrinsic base layer is in a contacting relationship with { HEAD ~ the second portion } of { TAIL ~ the intrinsic base layer }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 TAIL