A collar layer 12, preferably including a silicon oxide deposited by {HEAD ~ a CVD method}, is, subsequently, applied to the side walls of {TAIL ~ the trench} 5 
A collar layer 12 , preferably including a silicon oxide deposited by { HEAD ~ a CVD method } , is , subsequently , applied to the side walls of { TAIL ~ the trench } 5
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH