Yi-Jung LIU, Chih-Hung YEN, Chia-Hao HSU, Kuo-Hui YU, Li-Yang CHEN, Tsung-Han TSAI, and Wen-Chau LIU^*

Institute of Microelectronics, Department of Electrical Engineering, National Cheng-Kung University, 1 University Road, Tainan, Taiwan 70101, Republic of China

(Received June 8, 2009; Accepted August 20, 2009)

An interesting GaN-based light emitting diode (LED) using a 50 nm indium oxide (In₂O₃)/250 nm indium–tin oxide (ITO) mixed structure to replace the commonly used ITO (250 nm) current spreading layer is fabricated and studied. Use of the In₂O₃ layer could reduce the contact resistance of p-GaN in LEDs. In addition, this highly-resistive In₂O₃ layer, below the ITO layer could improve the current spreading performance. Experimentally, at room temperature, using this mixed structure, the luminous and EL intensities are enhanced by 17.7 and 17.1%, respectively.

Key words: GaN, light-emitting diode (LED), In₂O₃, ITO, specific contact resistance, transparent and conductive oxide (TCO)

^*E-mail address: wcliu@mail.ncku.edu.tw