AlN/GaN and InAlN/GaN DBRs

Abstract This chapter presents the high resolution monochromated STEM-EELS characterization of two distributed Bragg reflector (DBR) multilayer heterostructures, composed of a periodic staking of III-nitride layers. These heterostructures were grown by the group of E. Calleja at the Instituto de Sistemas Optoelectronicos y Microtecnologia (ISOM), from Universidad Politecnica de Madrid . One of these DBR is composed of an alternate staking of AlN and GaN layers, and the other one, of InAlN lattice matched to GaN. EELS at sub-nanometric spatial resolution and