Growth study of AlGaAs using dimethylethylamine alane as the aluminum precursor

We present a comprehensive study on the growth of AlGaAs by using an alternative Al precursor, dimethylethylamine alane (DMEAA), and a Ga coprecursor, either triethylgallium (TEG) or trimethylgallium (TMG). The growth rate of AlAs determined by using in situ reflectometry was studied as a function of the growth temperature, V/III ratio, growth pressure, and rotation speed of the substrate. The presence of gas phase reactions of DMEAA with arsine and TEG was indicated, and their reduction was achieved at a lower growth pressure, lower V/III ratio, or a lower growth temperature. Negligible pre-reaction of DMEAA with TMG was observed. Excellent material uniformity of AlGaAs was achieved on a 2″ diameter wafer. Secondary ion mass spectroscopy measurements revealed extremely low C and O contents in the AlAs layer grown by DMEAA. Photoluminescence measurements suggested the presence of some non-radiative defects in the as-grown DMEAA AlGaAs layers.