Adsorption and decomposition of trimethylarsenic on GaAs(100)
Alkylated arsenic compounds have shown some promise as alternatives to arsine as the group-V source gas for GaAs MOCVD. However, little is known about the fundamental chemical interactions of these compounds with the GaAs surface. We have investigated the adsorption and reactivity of trimethylarsenic (TMAs) on GaAs(100) using temperature programmed desorption (TPD), Auger electron spectroscopy, and LEED. For the exposures and temperatures studied, TMSs did not pyrolytically decompose on the GaAs(100). TPD results indicate that TMAs chemisorbs, apparently non-dissociatively, and desorbs approx. = 330 K. Multilayers of TMAs desorb approx. = 140--160 K. Exposure of adsorbed TMAs to 70 eV electron results in irreversible decomposition of the molecule. After electron irradiation, TPD shows that methyl radicals desorb at 660 K, which corresponds to a desorption activation energy of approx. = 40 kcal/mole. At higher temperatures, As2, H2, C2H2, and a smaller amount of methyl radicals desorb, and a small coverage of carbon remains on the surface. 10 refs., 4 figs.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 6618019
- Report Number(s):
- SAND-88-1665C; CONF-881155-35; ON: DE89005598
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
360602* -- Other Materials-- Structure & Phase Studies
360603 -- Materials-- Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
ARSENIC COMPOUNDS
ARSENIDES
ASTATINE COMPOUNDS
AUGER ELECTRON SPECTROSCOPY
CHEMICAL COATING
CHEMICAL REACTIONS
CHEMICAL VAPOR DEPOSITION
DECOMPOSITION
DEPOSITION
DESORPTION
ELECTRON SPECTROSCOPY
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HALOGEN COMPOUNDS
ORGANIC ARSENIC COMPOUNDS
ORGANIC COMPOUNDS
PNICTIDES
SPECTROSCOPY
SURFACE COATING
SURFACE TREATMENTS
TEMPERATURE EFFECTS