The effect of strain on hot-electron and hole longitudinal diffusion and noise in Si and Si0.9Ge0.1

Monte Carlo methods are used to model the electron and hole high-field transport in both unstrained and compressively strained silicon and silicon-germanium alloy. The data are analyzed to determine in what way the thermal noise properties of the carriers are affected by compressive, in-plane strain. Results include the longitudinal diffusion coefficient, the longitudinal noise temperature, and the longitudinal noise spectral density, for electric fields in the range of 0–20 kV/cm. The results are qualitatively similar for silicon with 1% compressive biaxial strain and for Si0.9Ge0.1/Si(001). The effects of strain are found to be more pronounced for electrons than for holes and are primarily related to changes in the conductivity effective mass.