(001)面任意方向单轴应变硅材料能带结构

首先计算了(001)晶面单轴应变张量,在此基础上采用结合形变势理论的K ·P微扰法建立了在(001)晶面内受任意方向的单轴压/张应力作用时,应变硅材料的能带结构与应力(类型、大小)及晶向的关系模型,进而分析了不同单轴应力(类型、大小)及晶向对应变硅材料导带带边、价带带边、导带分裂能、价带分裂能、禁带宽度的影响.研究结果可为单轴应变硅器件应力及晶向的选择设计提供理论依据. 关键词： 单轴应变硅 K ·P法 能带结构

Energy band structure of uniaxial-strained silicon material on the (001) surface arbitrary orientation

The strain tensor arising from uniaxial stress along an arbitrary direction on the (001) surface of Si is calculated. With these uniaxial strain tensor, the band structure of silicon material under arbitrary uniaxial stress on the (001) surface is calculated using K ·P perturbation theory coupled with linear deformation potential theory. The relation between energy band structure and stress parameters (type, direction, magnitude) was obtained. Finally, the uniaxial stress induced band structure change, such as that of the conduction band (CB) and the valence band (VB) edge levels, CB and VB splitting energy and the bandgap is demonstrated. Results of these band structure can be used as a guide for the design and the selection of the optimum strain and crystal orientation configuration of uniaxial strained silicon devices.