PHOTOEMISSION OVERVIEWS OF VALENCE BAND DENSITIES-OF-STATES FOR Ge, GaAs, GaP, InSb, ZnSe AND CdTe USING SYNCHROTRON RADIATION

We present photoemission overviews of major valence band fe~tures for the valence bands of several common group IV, 111-V and 11-VI semiconductors, which were obtained using synchrotron radiation in the 20-90 eV range from the 2.5 GeV storage ring at the Cambridge Electron Accelerator. Comparisons of our photoeniission data with empirical pseudopotential method (EPM) calculations fit to optical data show systematic and significant differences which typically increase with increasing ionicity. InSb is described in some detail, including measurements of core level binding energies, spin-orbit splittings and Auger processes. Several precautions when interpreting valence band photoemission measurenients in the 20 to 90 eV photon energy range are discussed (e. g. Auger processes, surface preparation, small matrix elements).