Linearity (commutativity and transitivity) of valence-band discontinuity in heterojunctions with Te-based II-VI semiconductors: CdTe, HgTe, and ZnTe

Abstract

Valence-band discontinuities, Δ${\mathrm{E}}_{\mathrm{v}}$, of the heterojunctions formed by combination of CdTe, HgTe, and ZnTe, grown in situ by molecular-beam epitaxy, are investigated by core-level x-ray photoemission spectroscopy. They are found to be insensitive to interface Fermi-level position, commutative, and transitive. Values measured for Δ${\mathrm{E}}_{\mathrm{v}}$ are 0.36±0.05 eV, 0.10±0.06 eV, and 0.25±0.05 eV for HgTe-CdTe(1¯ 1¯ 1¯), ZnTe-CdTe(1¯ 1¯ 1¯), and HgTe-ZnTe(1¯ 1¯ 1¯) heterojunctions, respectively. They are discussed in terms of linear-theory predictions.