The surface chemistry of triethylaluminum, triethylgallium, triethylindium, and triethylantimony was studied on GaAs(100) using thermal desorption spectroscopy, static secondary ion mass spectroscopy, and x‐ray photoelectron spectroscopy. Ethylene, the major hydrocarbon reaction product, desorbs from the GaAs(100) surface during thermal desorption spectroscopy experiments at 565 K for all four molecules. This indicates an identical rate limiting step for the elimination of ethyl groups from the surface following adsorption of these molecules. We propose that ethyl groups migrate to Ga sites and then undergo reaction at these sites. ©1995 American Institute of Physics.