The low-temperature (LT) epitaxial growth of high quality GaAs films is achieved by using triethylgallium and tertiarybutylarsine as the precursors. Without any external work, the deposition can be conducted at a temperature as low as 350 °C in a conventional metalorganic chemical vapor deposition system. The full width at half-maxi- mum of 77 K photoluminescence and X-ray rocking curve for a sample grown at 425 °C are 8.2 meV and 14 arcsec, respectively. Materials with good electrical properties were also obtained. A Schottky diode formed on the LT CaAs epilayer shows a barrier height of 0.83 eV, and a reverse saturation current of 1.1 × 10–7 A/cm2, comparable to that of a normal GaAs Schottky diode.