FACTORS INFLUENCING THE VARIATION OF SURFACE-ACOUSTIC-WAVE VELOCITY IN LITHIUM TETRABORATE

Comparison of the resonance frequency of surface acoustic wave (SAW) r esonators fabricated on defect-free and highly defective lithium tetra borate wafers was attempted. The intrinsic variation of SAW velocity d ue to crystal defects, impurities and chemical compositional inhomogen eities for lithium tetraborate wafers is smaller than +/-0.011%. In ad dition, the variation of SAW velocity in a wafer is influenced by the device fabrication process rather than the lithium tetraborate substra te quality.