Low-temperature deposition of hexagonal GaN films for UV electroluminescent devices by CS-MBE technique

Abstract

GaN-based electroluminescent devices (ELDs) operating in UV spectral region are proposed for the UV excitation source and their fabrication process using the compound-source molecular beam epitaxy (CS-MBE) technique. The trial substrates were (0 0 0 1)6H–SiC, Ta 2O 5/Al, and Ta 2O 5/glass substrates. In particular, the GaN buffer layer deposited at RT for the fabrication is discussed. The grown films were characterized by cathodoluminescence (CL), electroluminescence (EL), reflection high-energy electron diffraction (RHEED), and atomic force microscopy (AFM). The UV-light emission observed from the GaN-based ELDs fabricated using CS-MBE technique is demonstrated under operating conditions of 340 V at 200 Hz (pulsed wave). Red, green, and blue (RGB) pixels using phosphors (Y 2O 2S:Eu, BaMgAl 10O 17:Eu+Mn, BaMgAl 10O 17:Eu, respectively) were also demonstrated.