{HEAD ~ The method} 1, wherein the step of trimming comprises performing {TAIL ~ an isotropic etch} 
{ HEAD ~ The method } 1 , wherein the step of trimming comprises performing { TAIL ~ an isotropic etch }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL