High-Coupling and High-Temperature Stable Surface Acoustic Wave Substrates Using Groove-Type Interdigital Transducer

摘要

In this study, to obtain new substrates with the high coupling of electromechanical coefficients (k~2) and near-zero temperature coefficients of frequency (TCFs), very thin periodic grooves and interdigital transducers (IDTs) are fabricated on high-coupling substrates. Simulation results show a high k~2 (over 0.4) at H/λ = 0.1 for rotated Y-cut, X-propagating LiNbO_3 leaky surface acoustic wave substrates, and a high k~2 (over 0.08) and a small TCF (-10ppm/℃) at H/λ = 0.1 for 36° Y-cut, X-propagating LiTaO_3 leaky surface acoustic wave (SAW) substrates. The experimental results showed good agreements with the theoretical results.