Efficient pure green emission from Er-doped Ga2O3 films

Abstract

This study briefly reviews effect of the doping content on the structure, surface morphology, and optical properties of Er-doped Ga₂O₃ films on sapphire and Si substrates grown via pulsed laser deposition. Temperature insensitive pure green luminescence has been demonstrated from these films. We succeeded in fabricating light-emitting devices (LEDs) based on Ga₂O₃:Er/Si heterojunctions. Bright pure green emission can be observed by the naked eye from the LEDs. The driven voltage of these LEDs is 6.2 V, which is lower than those of ZnO:Er/Si and GaN:Er/Si devices. In addition, we determined the values of the valence band offset and conduction band offset of the Ga₂O₃/Si heterojunctions. The results obtained in this study shall provide a useful guideline for the development of Si-based green LEDs using Ga₂O₃ as the host materials for Er³⁺ ions.