{TAIL ~ A first dielectric layer} is formed overlying {HEAD ~ the substrate} and has a dielectric island surrounded by a ring shaped trench 
{ TAIL ~ A first dielectric layer } is formed overlying { HEAD ~ the substrate } and has a dielectric island surrounded by a ring shaped trench
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH