一种压电半导体纳米线的热电耦合性能研究

Study on Thermoelectric Coupling Characteristics of A Piezoelectric Semiconductor Nanofiber

摘要:

采用有限元分析方法,研究了一种n型压电半导体纳米线(氧化锌)的电热耦合性能,分析了外部温度对氧化锌纳米线内部机械场、电场及电流场分布的影响,并讨论了本构方程线性化对电学参数的影响。研究结果表明,温度对氧化锌纳米线的电场、载流子浓度和电流密度影响很大,采用线性本构和非线性本构求得的电场、电子浓度和电流密度最大相差分别为24%,32%和68%,基于非线性本构分析压电半导体的电学性能会引起很大误差。该研究结果可为压电半导体器件利用温度调控电场、电流提供理论依据。

Abstract:

The thermoelectric coupling characteristics of a kind of n-type piezoelectric semiconductor nanowire (ZnO) were studied with finite element method. The effects of external temperature on internal distribution of mechanical, electric and current fields of the ZnO nanowire were analyzed. And effects of the linearization of the constitutive equation on electric parameters were discussed. The results show that the external temperature greatly affects the electric field, carrier concentration and electric current density. The electric field, carrier concentration and current density derived from linear and nonlinear constitutive relation differ greatly, the maximum difference are 24%, 32% and 68%, respectively. A large error will appear when one adopts linear constitutive relation to analyze electric properties in piezoelectric semiconductors.