Hybrid Oblique-Angle Deposited ITO/Silver Nanowire Transparent Conductive Electrodes for Brighter Light Emitters

Abstract

In this paper, hybrid transparent conductive electrodes (TCEs) consisting of oblique-angle deposited indium tin oxide (OAD ITO) and silver nanowires (Ag NWs) were developed forGaN-based light-emitting diodes (LEDs). The 100-nm thick OAD ITO acted as an Ohmic contact to p-GaN with negligible light absorption having optical transmittance as high as approximately 99% at 450 nm, and Ag NWs acted as a favorable current spreader with sheet resistance as low as $19.9~\Omega $ /sq. Consequently, the hybrid TCEs consisting of OAD ITO and Ag NWs yielded an optical transmittance of 93% at 450 nm, a sheet resistance of 18.9 $\Omega $ /sq, and a specific contact resistance of ${2.1} \times {10}^{-2} \Omega \cdot $ cm2. LEDs fabricated with hybrid TCEs demonstrated improved electrical properties and greater optical output powers than the reference LEDs. This was due to the combined effects of the improved optical transparency, the enhanced current spreading, and the surface roughening effect.