Improved performance of Ga2O3/ITO-based transparent conductive oxide films using hydrogen annealing for near-ultraviolet light-emitting diodes

We investigated the use of transparent conductive oxide for near-ultraviolet light-emitting diodes based on co-sputtered gallium oxide (Ga2O3) and indium tin oxide (ITO). The electrical and optical properties of Ga2O3/ITO (IGTO) were observed to improve through hydrogen annealing, which resulted in a sheet resistance of 164 Ω/□ and an optical transmittance of 94% at increased carrier concentration and crystallization of the co-sputtered film through hydrogen annealing. Moreover, ohmic-like contacts were formed on the p-GaN substrate with a specific contact resistance of 3.9 x 10-1 Ω cm2. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)