Band Alignment Parameters of Al₂O₃/InSb Metal–Oxide–Semiconductor Structure and Their Modification with Oxide Deposition Temperatures

Abstract

From the Fowler–Nordheim (FN) current–voltage (I–V) characteristic and X-ray photoelectron spectroscopy (XPS) analysis, the conduction band offset of 2.73±0.1 eV and the valence band offset of 3.76±0.1 eV have been extracted for the atomic-layer-deposition (ALD) Al2O3/InSb structure. By these analyses, the parameters of an Al2O3 film including bandgap, electron affinity, and electron effective mass are also deduced. The capacitance–voltage and I–V characteristics of ALD Al2O3/InSb at different deposition temperatures indicate the modification of the Fermi level in InSb to 0.09 eV lower than that in metal side of the sample deposited at 250 °C as compared to the samples deposited at lower temperatures.