Charge confinement in heterojunction acoustic charge transport devices

Abstract

An equilibrium model is developed for charge confinement in heterojunction acoustic charge transport (HACT) devices. The Poisson–Boltzmann equation is solved for the self-consistent potential and packet charge distribution in a surface acoustic wave (SAW) superimposed on a (Al,Ga)As/GaAs hetrostructure. Numerical results are presented for the charge capacity of a 275 MHz HACT configuration. For a 1 V SAW potential, the charge capacity is limited by the heterojunction well depth rather than by space-charge lowering of the SAW barrier.