Low-field electron transport in quasi-one-dimensional semiconducting structures

The low-field drift mobility of electrons scattered by background and remote impurities, and by acoustic and polar optic phonons, is calculated for quasi-one-dimensional (Q1D) semiconducting structures using the relaxation time approximation. Approximate analytic expressions are derived for the momentum relaxation rate for the various scattering processes by assuming a 2D infinite potential well at the interfaces between the thin wire and cladding and using a momentum conservation approximation. The electron mobility is evaluated numerically in the size quantum limit and is found to be enhanced over the mobility of a 3D system if the phonon scattering is the dominant mechanism and if the transverse dimensions of the wire are large enough. The limitations of the present model are discussed in detail.