Influence of Uniaxial [110] Stress on the Silicon Conduction Band Structure: Stress Dependence of the Nonparabolicity Parameter
نویسندگان
چکیده
An alytical expression for the dependence of the nonparabolicity parameter on shear stress is presented. At 3 GPa the nonparabolicity parameter is shown to increase by a factor of 1.7. Stress dependence of the nonparabolicity parameter is verified by comparing the density-of-states obtained analytically and from the empirical pseudopotential method, and good agreement is found. Increase in the nonparabolicity parameter increases the after-scattering density-of-states and hence the scattering rates, which results in a 25% suppression of the mobility enhancement due to effective mass decrease in a 3 nm thin body FET at 3 GPa [110] stress.
منابع مشابه
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