Abstract
We combine reflectance anisotropy spectroscopy (RAS) with low energy electron diffraction, Auger electron spectroscopy, and soft x-ray photoemission spectra to analyze the surface optical anisotropy of ZnSe(OOl). Clean surfaces were prepared by thermal desorption of a protective Se cap from ZnSe layers of different thicknesses grown by molecular beam epitaxy on GaAs(001). Two surface reconstructions have been prepared by subsequent annealing, the Se-rich (2×1) reconstruction and the Zn-rich c(2×2) reconstruction. By modifying the surfaces either through submonolayer deposition of Sb or a short exposure to atmosphere it was possible to distinguish between surface and bulk/interface contributions to the optical anisotropy. Only on disordered, very Se-rich ZnSe(001) surfaces prepared at low annealing temperatures RAS features possibly related to electronic surface states are found. RAS spectra of the (2×1) and the c(2×2) surfaces are correlated with surface morphology and ordering rather than surface reconstruction and show features near the critical points of the bulk ZnSe band structure.
Original language | English |
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Pages (from-to) | 2350-2354 |
Number of pages | 5 |
Journal | Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures |
Volume | 16 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1998 |