Formation of an indium tin oxide nanodot/Ag nanowire electrode as a current spreader for near ultraviolet AlGaN-based light-emitting diodes. (19th December 2016)

• Record Type: Journal Article
• Authors: Park, Jae-Seong; Kim, Jae-Ho; Kim, Jun-Yong; Kim, Dae-Hyun; Na, Jin-Young; Kim, Sun-Kyung; Kang, Daesung; Seong, Tae-Yeon
• Is Part Of: Nanotechnology. Volume 28:Number 4(2017)
• Publication Date: 2016-12-19
• Subjects: Ag nanowire -- ITO nanodot -- NUV light-emitting diode -- current spreading; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/28/4/045205
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Indium tin oxide (ITO) nanodots (NDs) were combined with Ag nanowires (Ag NWs) as a p-type electrode in near ultraviolet AlGaN-based light-emitting diodes (LEDs) to increase light output power. The Ag NWs were 30 ± 5 nm in diameter and 25 ± 5 μ m in length. The transmittance of 10 nm-thick ITO-only was 98% at 385 nm, while the values for ITO ND/Ag NW were 83%–88%. ITO ND/Ag NW films showed lower sheet resistances (32–51 Ω sq −1 ) than the ITO-only film (950 Ω sq −1 ). LEDs (chip size: 300 × 800 μ m 2 ) fabricated using the ITO NDs/Ag NW electrodes exhibited higher forward-bias voltages (3.52–3.75 V at 20 mA) than the LEDs with the 10 nm-thick ITO-only electrode (3.5 V). The LEDs with ITO ND/Ag NW electrodes yielded a 24%–62% higher light output power (at 20 mA) than those with the 10 nm-thick ITO-only electrode. Furthermore, finite-difference time-domain (FDTD) simulations were performed to investigate the extraction efficiency. Based on the emission images and FDTD simulations, the enhanced light output with the ITO ND/Ag NW electrodes is attributed to improved current spreading and better extraction efficiency.