Calculation of the transverse acoustoelectric voltage in a piezoelectrichyphen;extrinsic semiconductor structure

摘要

The transverse acoustoelectric voltage (TAV) is calculated for a piezoelectrichyphen;extrinsic semiconductor structure. Using a smallhyphen;signal expansion an analytical but rather complicated expression is obtained and computed for the LiNbO3/nhyphen;Si system. New and simple expressions are given, respectively, for high and low conductivities. In the latter case the TAV can reverse sign as a function of the conductivity and the frequency. This effect is explained from the secondhyphen;order variations of the majority carrier concentration. The influence of the air gap between the piezoelectric and the semiconductor is also studied.