Transient capacitance spectroscopy on large quantum well heterostructures

Abstract
We report transient capacitance measurements on AlxGa1−xAs–GaAs–AlxGa1−xAs (x∼0.35) double heterojunctions with a large quantum well active region (Lz∼800 Å). It is suggested that the thin GaAs layer acts as a ‘‘giant’’ artificial deep level. It follows then that the band edge discontinuity ΔEc determines the electron emission rates (from the thin layer), thus making it possible for ΔEc to be determined by transient capacitance measurements.