ZnSe/ZnS↓(x)Se↓(1-x) Heterojunction Valence Band Discontinuity Measured by X-Ray Photoelectron Spectroscopy

摘要

X-ray photoelectron spectroscopy was used to measure the valence band discontinuity at the ZnSe/ZnS↓(x)Se↓(1-x) interface as a function of alloy composition. Due to the large lattice mismatch, the experimental values have to be corrected in order to account for strain in the ZnSe layers. We find the valence band discontinuity to vary between 0 and 0.76 eV as a function of S content x. This result is in excellent agreement with theoretical calculations. It also shows that the conduction band discontinuity is not negligibly small.