Low driven voltage green electroluminescent device based on Er:Ga2O3/GaAs heterojunction

Green light-emitting device (LED) based on Er:Ga2O3/GaAs heterojunction was fabricated in this work. Erbium (Er) doped Ga2O3 film was prepared on p-GaAs substrate by pulsed laser deposition. The structural, morphological and optical properties were investigated by X-ray diffraction, atomic force microscope and photoluminescence. Bright green electroluminescence dominated by 524 and 549 nm peaks can be observed with the naked eyes at a driven voltage of 6.0 V. These emissions were determined to be caused by the 4f-electron transitions of Er3+ from 2H11/2 -> 4I15/2, 4S3/2 -> 4I15/2, respectively. It is determined that the Er-related green electroluminescence arose from transfer of the energy released from the defect-assisted indirect recombination in the Ga2O3 host to the Er ions. We believe that the fabrication of green LED based on Er:Ga2O3/GaAs heterojunction will make contribution to future integration of optoelectronic devices compatible with GaAs technology.