Acoustic phonon scattering in silicon quantum dots

Intravalley acoustic phonon scattering of electrons in fully quantized systems based on n-type inversion layers on a (100) surface of p-type Si is studied theoretically. The confining potential normal to the Si/SiO2 interface is modelled by a triangular quantum well. For the confinement in the lateral directions we assume a parabolic potential. The calculations reveal that the anisotropic electron-acoustic-phonon interaction strongly affects the scattering rate and the average scattering angle. The calculated transition rate of electrons from the first excited state to the ground state shows a strong dependence on spatial confinement and lattice temperature, with the longitudinal phonon mode giving the main contribution to the total rate.