HAADF STEM and PL Characterization of Monolayer-Thick GaN/(Al,Ga)N Quantum Wells for Deep UV Optoelectronics Applications

A few monolayer-thick (ML) GaN quantum well (QW) structures are promising for high-power optoelectronic applications in mid-UV wavelength ranges [1-2]. High Resolution Transmission Electron Microscopy (HRTEM) and especially High Angle Annual Dark Field (HAADF) Transmission Electron Microscopy (STEM) appear to be a key metrology to establish a relationship between atomic structure and optical properties of nanostructures. TEM/STEM also provides an effective pathway for optimization of crystal growth of ML thick nanostructures [1]. Here we report TEM analysis of 1-5 ML thick GaN QWs in conjunction with optical research of peculiarities of their electronic band structure.