The electrical properties of AlxGa1−xAs (0≤x≤0.44) grown by organometallic vapor phase epitaxy using trimethylamine alane as the Al precursor were investigated. High‐quality AlGaAs Schottky barriers were fabricated and characterized by current–voltage, capacitance–voltage, and deep level transient spectroscopy measurements. The epilayers showed excellent electrical characteristics with low overall trap concentrations. In particular, the AlxGa1−xAs layers contained very low concentrations of EL2. ©1995 American Institute of Physics.