SAW device applications of longitudinal leaky surface waves onlithium tetraborate

摘要

The possibility of high frequency SAW device applications ofnlongitudinal leaky surface waves (LLSW) on lithium tetraborate (Li2nB4O7; LBO) is investigated in this paper. Annelectrical equivalent circuit model (ECM) is extended in order tonconsider effects of bulk wave scattering for the LLSWs. The equivalentncircuit parameters used in the extended ECM for designing the LLSWndevices are directly determined from numerically calculated dispersionncurves. For applications of the LLSW, high frequency SAW filters on LBOnwith the Euler angles (0°, 47.3°, 90°) are demonstrated. Asnexamples of the high frequency devices, 1.5 GHz and 1.2 GHz SAW filtersnusing the mode are designed by using the extended ECM, and fabricated bynusing conventional patterning processes. One is for the filter of thenglobal positioning system (GPS), another is for the 1.2 GHz band datantransmission radio system in Japan. As a result, low loss SAW filtersncan be obtained easily without submicron fabrication techniques by usingnthe LLSWs on LBO. Furthermore, the frequency response calculated by thenextended ECM are in a good agreement with the experiments