The first results of the electrons drift velocity study in inverted AlGaAs/InGaAs/GaAs pseudomorphic heterostructures with donor-acceptor doping and short-period AlAs/GaAs superlattices are presented. It is theoretically shown that the introduction of superlattices significantly, up to one and a half times, increases the electrons drift velocity overshot when they enter the region of a strong field. Localized states in the superlattice between the quantum well and the substrate have been found. It is shown that this effect leads to an additional increase in the electrons drift velocity overshot up to the theoretical limit for the model used, i. e., a drift velocity overshot in the bulk material of the quantum well. Keywords: inverted heterostructure, digital barriers, field-effect transistor, gain.

The processes of nonlocal electron heating in transistor heterostructures based on gallium nitride and gallium arsenide were compared. It has been shown that, in the case of GaAs double doped pseudomorphic heterostructures, the real space transfer of electrons significantly reduces their drift velocity overshot in the region of a strong field as compared with pure bulk GaAs, while in GaN-based heterostructures the decrease in the drift velocity overshot does not exceed 30% in the studied cases. Keywords: Real space transfer, field-effect transistor, gain factor