压应变SiGe和张应变Si的能带结构研究  

Band Structure of Compressive Strained SiGe and Tensile Strained Si

作　　者：周志文[1] 叶剑锋[1] 李世国[1] 

机构地区：[1]深圳信息职业技术学院电子与通信学院,广东深圳518172

出　　处：《固体电子学研究与进展》2016年第1期1-5 59,共6页Research & Progress of SSE

基　　金：广东省高等学校优秀青年教师资助项目(Yq2014123);深圳市科技计划资助项目(JCYJ20120821162230170)

摘　　要：根据体Si和体Ge的能带结构特点,基于形变势理论,计算了SiGe合金的应变对其能级的影响。静压应变导致能级偏移,单轴应变导致简并能级分裂,使得应变SiGe合金的禁带宽度随应变的增加而减小。共度生长在体Si衬底上的SiGe合金,以及共度生长在体SiGe衬底上的Si,它们的禁带宽度随Ge组份的增加近乎线性减小。完全压应变的Si_(0.5)Ge_(0.5)合金,其禁带宽度从无应变时的0.93eV减小为0.68eV。Ge组份为0.5时,完全张应变的Si,其禁带宽度从无应变时的1.12eV减小为0.85eV。Based on the band structures of bulk Si and bulk Ge,the effect of strain on the band structures of strained SiGe alloys was investigated by deformation potential theory.The strain has two effects on the band structure:the hydrostratic strain component shifts the position of a band,and the uniaxial strain component splits the degenerate bands,leading to the shrinkage of the bandgap.The bandgaps of compressive strained SiGe alloy pseudomorphically grown on bulk Si substrate decline as the Ge content increases,as well as tensile strained Si pseudomorphically grown on bulk SiGe substrate.Totally compressive strained Si_(0.5)Ge_(0.5)alloy on bulk Si substrate has a bandgap of 0.68 eV,which is reduced from 0.93 eV of bulk Si_(0.5)Ge_(0.5).And fully tensile strained Si on bulk Si_(0.5)Ge_(0.5)substrate has a bandgap of 0.85 eV,while the bandgap of bulk Si is 1.12 eV.

关 键 词：SIGE合金 应变 能带结构 形变势理论 

分 类 号：TN304[电子电信—物理电子学]