Since {HEAD ~ the second diffused layer} has {TAIL ~ a high concentration}, the short channel effect can be suppressed 
Since { HEAD ~ the second diffused layer } has { TAIL ~ a high concentration } , the short channel effect can be suppressed
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH