Characterization of a-Plane GaN/(Al,Ga)N Multiple Quantum Wells Grown via Metalorganic Chemical Vapor Deposition

The structural and optical properties of a 10-period (10.7 nm GaN) /(10.1 nm Al0.25Ga0.75N) multiple quantum well structure grown on an a-plane GaN template layer were investigated. Despite high threading dislocation density (approximately 3 x 1010 cm-2) and surface undulations, abrupt quantum well interfaces produced well-defined satellite peaks out to the second order in a symmetric high-resolution XRD scan. Thorough analysis of XRD measurements (kinematical analysis and dynamic simulations) provided accurate measurements of the quantum well dimensions and barrier composition. RT photoluminescence emission from the structure exhibits quantum confinement consistent with quantum wells free of polarization-induced electric fields. 14 refs.