A quick wet etching process is performed to remove a portion of the remaining first oxide located on {HEAD ~ the top} of the gate structure and on {TAIL ~ the substrate} 
A quick wet etching process is performed to remove a portion of the remaining first oxide located on { HEAD ~ the top } of the gate structure and on { TAIL ~ the substrate }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL