Threshold voltage shift characterization of vertically stacked InAs nanodots in field-effect transistor

An Al0.5Ga0.5As/GaAs heterojunction field-effect transistor which consists of InAs nanodots in the barrier layer and a GaAs quantum well channel is gr own by molecular beam epitaxy and the device performance and the electron t ransport from the quantum well to the nanodots are studied. These InAs nano dots are grown by self-assembling in a vertically stacked form, and their o ptical and electrical properties are characterized by photoluminescence and capacitance-voltage measurements. The electrical injection of electrons co nfined at the nanodots produces a persistent electron trapping which yields a memory function in the device performance. showing a potential applicati on for room-temperature operation. (C) 2001 Elsevier Science B.V. All right s reserved.