一种可获得“迁移率谱”的新方法——瞬时热电效应法

A NEW TECHNIQUE FOR OBTAINING THE “MOBILITIES SPECTRUM” TRANSIENT THERMOELECTRIC EFFECT

介绍了瞬时热电效应法，一种新的实验手段．它基于脉冲激光照射引起的载流子的扩散现象．观测到的瞬时热电电压由光激发导致的传导载流子的扩散形成，并且复合着几个特征的衰减过程指数地衰减．分析这些衰减过程，可以获得载流子的迁移率、有效质量、费密面的变化等重要信息．对瞬时热电效应法的原理以及主要分析方法作了较详细的介绍．

Abstract We introduced a new technique called “Transient Thermoelectric Effect (TTE)”, which was based on carrier diffusion as irradiated by a pulsed laser. The observed TTE voltages decayed exponentially with time, showing a multi relaxation process with characteristic relaxation times τ i(i=1,2,3,…) for thermal diffusions of photo induced conduction carriers, analyses of these results could give valuable information about carrier mobilities, effective masses and Fermi surfaces. The principle and the main analysis method were also described in detail.