[OPTICAL REVIEW Vol. 16, No. 6 (2009) 575-577]
© 2009 The Optical Society of Japan

Impact of An Indium Oxide/Indium–Tin Oxide Mixed Structure for GaN-Based Light-Emitting Diodes

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