应变Si／（001）Si1-x Gex电子迁移率

摘要

According to the model of ionized impurity scattering, acoustic phonon intravalley scattering and optical phonon intervalley scattering, the dependences of electron mobility of strained Si/（001 ）Si1-x Gex with different germanium constituents on impurity concentration are studied based on Subband occupation by solving Boltzmann equation. The results show that electrons almost totally occupy the A2 valley when germanium constituent is up to 0.2, and the mobility with germanium constituent 0.4 is 64% higher than that of the unstrained silicon at low impurity concentration; and vertical channel is not so good for tensile stained Si devices. The model can also be used to calculate the electron mobility of other crystal face with an arbitrarily orientation if the parameters are correctly chosen, so the model offers some useful foundation for strained silicon devices and circuits.%依据离化杂质散射、声学声子散射和谷间散射的散射模型，在考虑电子谷间占有率的基础上，通过求解玻尔兹曼方程计算了不同锗组分下，不同杂质浓度时应变si／（001）Si1-x Gex的电子迁移率．结果表明：当锗组分达到0．2时，电子几乎全部占据△：能谷；低掺杂时，锗组分为0．4的应变si电子迁移率与体硅相比增加约64％；对于张应变SiNMOS器件，从电子迁移率角度来考虑不适合做垂直沟道．选择相应的参数，该方法同样适用于应变si其他晶面任意方向电子迁移率的计算，为应变si器件、电路的设计提供了一定的设计依据．