应变Si1－xGex/(111)Si空穴有效质量模型

利用应变Si_1-xGe_x/(111)Si材料价带E(k)-k关系，研究获得了沿不同晶向的空穴有效质量，并在此基础上，建立了空穴各向同性有效质量模型.结果表明，与弛豫材料相比，应变Si_1-xGe_x/(111)Si材料价带带边空穴有效质量各向异性更加显著，带边空穴各向同性有效质量随Ge组分明显减小.该研究成果可为Si基应变PM关键词：1-xGe_x')" href="#">应变Si_1-xGe_x空穴有效质量价带

Model of hole effective mass of strained Si_(1-x)Ge_x/(111)Si

There has been much interest in the Si-based strained technology lately. The research on the hole effective mass of Si-based strained material is the theoretical basis for the performance enhancement of Si-based strained PMOS devices. Based on the valence band E(k)-k relation of strained Si_1-xGe_x/(111)Si, the hole effective mass along arbitrarily k wavevector direction were obtained. And the hole isotropic effective mass models were established. It was found that in comparison with relaxed Si, the more obvious anisotropy of the hole effective mass occurs in strained Si_1-xGe_x/(111)Si and the hole isotropic effective mass of the top valence band decreases obviously with increasing Ge fraction. The results can supply valuable references to the conduction channel design related to stress and orientation in the Si-based strained PMOS devices.