ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Initial sticking probabilities are measured for monoenergetic molecular chlorine upon the Ga-rich GaAs(100) c(8×2), As-rich GaAs(100) c(2×8), and stoichiometric GaAs(110)(1×1) surfaces. The sticking probabilities are measured as a function of incident translational energy (0.038–0.66 eV), surface temperature (256–807 K), and angle of incidence (0°–37°). Our data indicate the presence of both precursor and direct activated chemisorption mechanisms on all three surfaces. The average barriers to direct chemisorption are quite similar on these three surfaces, suggesting both structural and elemental insensitivity for the direct component to chemisorption. In addition, there is evidence of direct barrierless chemisorption on the Ga-rich GaAs(100) c(8×2) and stoichiometric GaAs(110)(1×1) surfaces. In contrast, precursor mediated chemisorption is seen to differ for the Ga-rich GaAs(100) c(8×2) and stoichiometric GaAs(110)(1×1) surfaces with the precursor persisting to higher incident energies on the stoichiometric GaAs(110)(1×1) surface (∼0.5 eV) than on the Ga-rich GaAs(100) c(8×2) surface (∼0.35 eV). Total energy scaling is observed on both the Ga-rich GaAs(100) c(8×2) surface and the stoichiometric GaAs(110)(1×1) surface for both precursor mediated and direct activated chemisorption, indicating highly corrugated gas-surface interaction potentials.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.466591
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