The suitability of several Sn‐containing molecules (tetramethyltin, tetrabutyltin, dibutyltin dibromide, and stannic chloride) as gas phase sources of Sn for use in molecular beam epitaxy of GaAs was evaluated.InsituAuger electron spectroscopy showed that the Sn molecules absorbed at approximately the monolayer level at room temperature on GaAs (001) epilayer surfaces and pyrolytically decomposed before desorption. Capacitance–voltage and secondary ion mass spectrometry profiles demonstrated that the pyrolytic Sn deposits incorporated as ann‐type dopant into newly regrown GaAs epilayers. Sn films were ultraviolet (UV) photolytically deposited on GaAs from each of these Sn‐containing molecules and characterized by x‐ray photoelectron spectroscopy.