Alternatively, {TAIL ~ a silicon substrate} may be used instead of the substrate and {HEAD ~ the oxide layer} 
Alternatively , { TAIL ~ a silicon substrate } may be used instead of the substrate and { HEAD ~ the oxide layer }
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD