Structural properties of quaternary InAlGaN MQW grown by plasma‐assisted MBE

Abstract

Quaternary In0.085Al0.285Ga0.63N/GaN multiple quantum wells (MQW) grown by plasma‐assisted molecular beam epitaxy are characterized by high resolution transmission electron microscopy (HRTEM), geometric phase analysis, and energy dispersive X‐ray (EDX) nano‐analysis. The MQW exhibit sharp well‐defined InAlGaN/GaN interfaces while the GaN/InAlGaN interfaces are more smeared. The InAlGaN quantum wells and the GaN barriers are lattice‐matched. Chemical distribution profiles are extracted from EDX line scans, obtained with a nanoprobe, which are compared to convoluted theoretical profiles, and are in good agreement with the HRTEM observations. Indium clustering occurs after prolonged observation under the electron beam. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)