Under {TAIL ~ previous processes} in {HEAD ~ the related art}, surface roughness and sloped sidewall problems occur 
Under { TAIL ~ previous processes } in { HEAD ~ the related art } , surface roughness and sloped sidewall problems occur
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH