Studies of the tunneling currents in the InAs/AlSb/GaSb single-barrier interband tunneling diodes grown on GaAs substrates

This paper studies the tunneling currents in the single-barrier InAs/AlSb/GaSb interband tunneling structures, with an emphasis on correlating with the bandedge alignment. The WKB approximation combined with the k⋯p two-band model are used to analyze the interband tunneling currents versus the barrier widths to obtain the energy level in the AlSb barrier through which the peak tunneling currents occur. The obtained energy level (0.48 ± 0.1 eV above the valence band maximum of the AlSb) agrees with the valence-band offset between AlSb and GaSb. A good agreement of the measured peak voltages and the C - V data with the predicted values by the theory using a self-consistent Schrödinger-Poisson solver is obtained, with a value of 0.15-0.2 eV for the InAs/GaSb band overlap.