摘要
Intrinsic carrier concentration(ni) is one of the most important physical parameters for understanding the physics of strained Si and Si1-xGex materials as well as for evaluating the electrical properties of Si-based strained devices. Up to now, the report on quantitative results of intrinsic carrier concentration in strained Si and Si1-xGex materials has been still lacking. In this paper, by analyzing the band structure of strained Si and Si1-xGex materials, both the effective densities of the state near the top of valence band and the bottom of conduction band( Nc and Nv) at 218, 330 and 393 K and the intrinsic carrier concentration related to Ge fraction(x) at 300 K were systematically studied within the framework of KP theory and semiconductor physics. It is found that the intrinsic carrier concentration in strained Si(001) and Si1-xGex(001) and(101) materials at 300 K increases significantly with increasing Ge fraction(x), which provides valuable references to understand the Sibased strained device physics and design.
Intrinsic carrier concentration(ni) is one of the most important physical parameters for understanding the physics of strained Si and Si1-xGex materials as well as for evaluating the electrical properties of Si-based strained devices. Up to now, the report on quantitative results of intrinsic carrier concentration in strained Si and Si1-xGex materials has been still lacking. In this paper, by analyzing the band structure of strained Si and Si1-xGex materials, both the effective densities of the state near the top of valence band and the bottom of conduction band( Nc and Nv) at 218, 330 and 393 K and the intrinsic carrier concentration related to Ge fraction(x) at 300 K were systematically studied within the framework of KP theory and semiconductor physics. It is found that the intrinsic carrier concentration in strained Si(001) and Si1-xGex(001) and(101) materials at 300 K increases significantly with increasing Ge fraction(x), which provides valuable references to understand the Sibased strained device physics and design.
基金
Funded by the National Natural Science Foundation of China(Nos.51278058,41404095,51277012,61201233)
the Fundamental Research Funds for the Central Universities(Nos.2013G1241120,2013G1241107,2013G1241114,CHD2011ZD004)
Research Fund of Shaanxi Provincial Research Center for Telecommunication ASIC Design(No.SXASIC2014-1)
the Shaanxi Science and Technology Research and Development Program(No.2013KJXX-93)