Effect of pressure on electrical properties of short period InAs/GaSb superlattice
Abstract
In this paper, we present resistivity and Hall measurements on InAs/GaSb Superlattice (SL) grown by Molecular Beam Epitaxy (MBE) on GaAs semi-insulating substrate. Measurements have been carried out under hydrostatic pressure up to 1300 MPa in the temperature range 80–300 K. We observe that the sample exhibits a reproducible change in conductivity type. The SL is n-type at high temperatures range whereas it is p-type at low temperature. The characteristic temperature Tch at which the switch of conductivity type occurs increases with pressure from Tch = 190 K to 280 K at highest pressure. The room temperature results are characterized by a strong increase of resistivity with pressure. The room-temperature Hall mobility varies from 1350 cm2/V s for ambient pressure to 345 cm2/V s for P = 1210 MPa. This strong effect of pressure on electrical transport properties of material suggests that at room temperature at least two types of electrons respectively with high and low mobility take part in the conduction process. The low mobility carriers could be related to the L mini band. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
