Metalorganic Vapor-Phase Epitaxial Growth and Characterization of Cubic Al_xGa_1-xN Alloy

Abstract

Cubic Al x Ga 1- x N alloy films in the range 0≤ x ≤0.51 were grown on GaAs (100) substrates using low-pressure metalorganic vapor-phase epitaxy. The lattice constants of the alloys, which were estimated from the X-ray diffraction peaks, obeyed Vegard's rule. The optical quality of the alloys was improved by using triethylaluminum as the aluminum precursor. In photoluminescence measurements, Al x Ga 1- x N in the range x ≤0.42 exhibited strong near band edge emissions, while that with x around 0.5 did not. The peak energy of the photoluminescence depended on the relationship E =3.20+1.85 x in the range x ≤0.42, while that around x =0.5 was less than that given by this relationship.