Room-temperature operation of a memory-effect AlGaAs/GaAs heterojunction field-effect transistor with self-assembled InAs nanodots

This letter describes the memory effect of an AlGaAs/GaAs heterojunction field-effect transistor that contains InAs nanodots in the barrier layer. The device experiences a shift of threshold gate voltage, as a function of the amount of the electrons trapped in the nanodots. These trapped electrons can be injected by applying a positive gate voltage and be erased by a visible light illumination at negative gate bias. Although the shift of the threshold gate voltage volatilizes with the time after the memory programing operation, a considerable part of the shift is retained even after 100 h at room temperature. (C) 2000 American Institute of Physics. [S0003-6951(00)03711-6].