Investigation on Low-Angle Boundary and SAW Property of LiTaO_3 Piezoelectric Single Crystal

摘要

Etched micrograph of low-angle boundary are observed using SEM and range of low-angle boundary are quantitatively measured by rocking curve & reciprocal space map of HRTAXRD for piezoelectric single crystal Z-Y-LiTaO_3, and insertion loss of SAW devices are tested that are made on above samples including low-angle boundary to investigate influence of it to SAW property. Results show that low-angle boundary of samples are consisted of a series of overlap dislocations which belong to symmetrical tilt boundary, and mainly misorientation is 45.22 arcsec and the biggest one 115.98 arcsec. Insertion loss of SAW devices with low-angle boundary display increase that are from 2.5 percent to 9.3 percent than normal ones and disperse that maximal difference of loss is 2.05 dB while 0.32 dB in normal areas, also advantages to characterize low-angle boundary using HRTAXRD are discussed.