Metalorganic molecular beam epitaxy (MOMBE) growth characteristics of GaAs using triethylgallium (TEGa) and trisdimethylaminoarsenic (TDMAAs) are studied in detail by using reflection high energy electron diffraction intensity oscillations. It is found that the GaAs growth rate variation with substrate temperature (Tsub) is similar to that in the MOMBE growth of GaAs with TEGa and elemental As (As4) except in the highTsubregion, despite the use of uncracked TDMAAs instead of As4. GaAs growth starts at about 350 °C and shows a maximum growth rate at about 500 °C. However, the absolute growth rate is about 15% lower than that using As4with the same TEGa flow rate in the mass‐transport limited growth region. Above 600 °C the growth rate shows a rapid decrease with increasingTsub. Further, it is found that etching of GaAs occurs when only TDMAAs is supplied to the GaAs surface atTsubabove 500 °C. Unintentionally doped GaAs films shown‐type conduction in the wholeTsubrange investigated with the highest 77 K electron mobility of 22 000 cm2/V s and a low carrier concentration of 2×1015cm−3for the 650 °C grown samples. 4.2 K photoluminescence spectra show an exciton‐bound‐to‐impurity emission peak at the wavelength of 819.3 nm with a full width at half‐maximum of less than 3.5 meV indicating good optical qualities. ©1995 American Institute of Physics.