Temperature control of morphology and barrier formation at the In/GaAs(110) interface

A photoemission spectroscopy study has been performed to investigate the 80 K low temperature (LT) to room temperature (RT) transition at the In/GaAs(110) interface. In/GaAs interfaces prepared at LT were slowly brought to RT while changes in overlayer morphology and band bending were observed via the Ga 3d and In 4d core level spectra. When several monolayers of In were deposited on LT p‐GaAs and this interface was subsequently warmed to RT, the band bending increased from the high‐coverage value of 0.5 eV to the 0.8 eV ‘‘overshoot’’ value that is seen at submonolayer coverages. From examination of the In 4d spectra, the In overlayer was found to cluster strongly upon warming, but In chemisorbed to the substrate remained between the clusters. The return of the overshoot that accompanies this In clustering may be explained by attributing the overshoot to states provided by the chemisorbed In. This reovershoot upon clustering further implies that the high‐coverage pinning of the In/LT p‐GaAs is due directly to the presence of the In overlayer rather than deposition‐induced defects in the GaAs.