A wet etching process is performed to remove {HEAD ~ the first un etched portion} of {TAIL ~ the substrate} after the mask removing process, thereby forming the piezoelectric resonator element 
of
A wet etching process is performed to remove { HEAD ~ the first un etched portion } of { TAIL ~ the substrate } after the mask removing process , thereby forming the piezoelectric resonator element
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH