TY - JOUR
T1 - Synchrotron radiation induced surface photovoltage at metal/GaAs interfaces
AU - Mao, D.
AU - Kahn, A.
AU - Marsi, M.
AU - Margaritondo, G.
N1 - Funding Information:
The authors wish to thank the staff of the Wisconsin Synchrotron Radiation Center which is supported by the National Science Four,clarion. This work was supported by a grant of the National Science Foundation (DMR-8709531) and by the Office of Naval Research.
PY - 1991
Y1 - 1991
N2 - We use the Kelvin method to study the synchrotron radiation induced surface photovoltage (SPV) on GaAs(110) as a function of metal coverage and temperature. We find that varying the temperature alone does not induced significant change in band bending in the semiconductor, but that the combination of low temperature and synchrotron light illumination on lightly doped n-GaAs induces a large and quasi-permanent SPV. On lightly doped n-GaAs, the low-temperature SPV (0.55 eV) is equal to the quasi-totality of the band bending at submonolayer coverage and discharges with a time constant of the order of hours. Above a monolayer, the rate of discharging increases dramatically, emphasizing the role of charge leakage through the overlayer. The room temperature SPV is considerably smaller (0.2 eV). Finally, no significant SPV is detected on highly doped GaAs. The impact of this synchrotron radiation induced SPV on the photoemission study of metal/semiconductor interfaces is discussed in detail.
AB - We use the Kelvin method to study the synchrotron radiation induced surface photovoltage (SPV) on GaAs(110) as a function of metal coverage and temperature. We find that varying the temperature alone does not induced significant change in band bending in the semiconductor, but that the combination of low temperature and synchrotron light illumination on lightly doped n-GaAs induces a large and quasi-permanent SPV. On lightly doped n-GaAs, the low-temperature SPV (0.55 eV) is equal to the quasi-totality of the band bending at submonolayer coverage and discharges with a time constant of the order of hours. Above a monolayer, the rate of discharging increases dramatically, emphasizing the role of charge leakage through the overlayer. The room temperature SPV is considerably smaller (0.2 eV). Finally, no significant SPV is detected on highly doped GaAs. The impact of this synchrotron radiation induced SPV on the photoemission study of metal/semiconductor interfaces is discussed in detail.
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U2 - 10.1016/0169-4332(91)90352-K
DO - 10.1016/0169-4332(91)90352-K
M3 - Article
AN - SCOPUS:0026155457
SN - 0169-4332
VL - 48-49
SP - 324
EP - 331
JO - Applied Surface Science
JF - Applied Surface Science
IS - C
ER -