GHz voltage amplification in a stack of piezoelectric ScAlN and non-piezoelectric SiO₂ layers

Abstract

GHz voltage amplification was found in a stacked structure of piezoelectric layers, such as ScAlN, and non-piezoelectric layers, such as SiO2. This allows for large-area fabrication using commercial equipment. This approach contributes to wireless sensor activation. The electromechanical coupling coefficients k t 2 of input and output layers were 17.6% and 13.7%, respectively. An experimental open-circuit voltage gain of 4.5 (+13 dB) at 0.8 GHz was observed, with a maximum transmission loss (S21) of -5 dB. The experimental result shows good agreement with the theoretical prediction simulated by electromechanical transmission line model.