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

Abstract

Valence-band discontinuities, \ensuremath{\Delta}${\mathrm{E}}_{\mathrm{v}}$, 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 \ensuremath{\Delta}${\mathrm{E}}_{\mathrm{v}}$ are 0.36\ifmmode\pm\else\textpm\fi{}0.05 eV, 0.10\ifmmode\pm\else\textpm\fi{}0.06 eV, and 0.25\ifmmode\pm\else\textpm\fi{}0.05 eV for HgTe-CdTe(1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{}), ZnTe-CdTe(1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{}), and HgTe-ZnTe(1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{}) heterojunctions, respectively. They are discussed in terms of linear-theory predictions.