INTERFACE EFFECTS, BAND OVERLAP AND THE SEMIMETAL TO SEMICONDUCTOR TRANSITION IN INAS/GASB INTERBAND RESONANT-TUNNELING DIODES

We report some of the highest 77 K peak to valley ratios (PVRs) for single heterojunction InAs(n)/GaSb(p) resonant conduction diodes. The devices were grown with low background doping (n almost-equal-to p almost-equal-to 10(16) cm-3) on (100) oriented substrates by atmospheric pressure MOVPE, and were prepared by switching the precursors in a predetermined order, to have ''InSb'' or ''GaAs'' like interfaces. We observe a stronger resonance with a weaker temperature dependence when the interface is ''GaAs'' like. In all samples, the voltage of the resonance and the peak current both decrease with hydrostatic pressure due to the pressure induced decrease of band overlap. Our results are consistent with a shift of - 10 meV/kbar, and overlaps of 120 +/- 20 meV and 250 +/- 50 meV respectively for ''InSb'' like and ''GaAs'' like interfaces, and are in agreement with high pressure parallel transport results in superlattices with ''InSb'' like interfaces.