The transient response of hot electrons in quasi-two-dimensional semiconductors

Abstract

The behavior of hot electrons in quasi-two-dimensional semiconductors has been calculated, using a displaced Maxwellian distribution function applied to a 〈100〉 inversion layer in silicon. Under a high electric field, energy levels become grouped into subbands, so that motion of carriers perpendicular to the surface becomes quantized; thus, the energy, momentum, and population transfer relaxation times appropriate to the individual levels must be considered in the calculations, along with their relation to velocity overshoot. Previous work has been performed under the assumption that intervalley scattering is a local phenomenon, i.e., a function only of electron temperature of the initial valley. In this paper, this assumption is relaxed, and the intervalley coupling of electron temperature is taken into account. dc and transient response characteristics for both uncoupled and coupled models are performed, and the results are compared.