Implementation of an indium-tin-oxide (ITO) direct-Ohmic contact structure on a GaN-based light emitting diode
Yi-Jung Liu1, Chien-Chang Huang, Tai-You Chen
1Department of Electrical Engineering, Institute of Microelectronics, National Cheng-Kung University, University Road, Tainan 7010, Taiwan.
Abstract:
A GaN-based light-emitting diode (LED) with a direct-Ohmic contact structure, formed by an indium-tin-oxide (ITO) transparent film and Au thermal-diffused and removed layer, is studied. By depositing an Au metallic film on the Mg-doped GaN layer followed by thermal annealing and removed processes, an ITO direct-Ohmic contact at p-GaN/ITO interface is formed. An enhanced light output power of 18.0% is also found at this condition. This is mainly attributed to the larger and more uniform light-emission area resulted from the improved current spreading capability by the use of an ITO direct-Ohmic contact structure.
