Angle‐resolved photoemission study of GaAs(100) surfaces grown by molecular beam epitaxy

Angle‐resolved ultraviolet photoemission spectroscopy (ARUPS) using synchrotron radiation has been used to advance our understanding of the surface electronic structure of reconstructed GaAs(100) surfaces. ARUPS spectra were taken using a variable energy polarized photon source (ℏω=15–100 eV). GaAs(100) surfaces with (1×2), c(8×2), and (4×6) reconstructed structures were grown in situ by molecular beam epitaxy (MBE) and characterized by in situ Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). Surface state peak positions were measured across the surface Brillouin zone and the peak positions and dispersion characteristics were determined. The results were consistent with occurrence of the backbonded surface states for ideal GaAs(100) surfaces described by Pollman and Pantelides. Some surface state structures not predicted by them were also observed. The (1×2) As‐stabilized surface showed surface states with bonding energies of −6.0 and −9.0 eV corresponding to the two backbonde...