{HEAD ~ A thickness} of about 700 to 900 Å of a silicon nitride film is suitable for {TAIL ~ a refractive index} of about 1.9 to 2.0 
is suitable for
{ HEAD ~ A thickness } of about 700 to 900 Å of a silicon nitride film is suitable for { TAIL ~ a refractive index } of about 1.9 to 2.0
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH