PIEZOELECTRIC POTENTIAL UNDER 2-DIMENSIONAL SUPERLATTICES

Differential thermal contraction generates stress under gates on the s urface of a semiconductor, which in turn induces a potential in a two- dimensional electron gas underneath. We have calculated the deformatio n and piezoelectric potentials under square and circular gates on comm on III-V surfaces. The piezoelectric potential is complicated and show s lower symmetry than the gate, which must be taken into account when designing superlattices. The deformation potential does not break the symmetry but is about an order of magnitude smaller. (C) 1998 Publishe d by Elsevier Science B.V. All rights reserved.