# Performance Enhancement of GaN-Based Light-Emitting Diodes by Using Transparent Ag Metal Line Patterns

Chi Shiang Hsu, Sheng Yi Chen, Jian Kai Liou, Wei Cheng Chen, Ching Hong Chang, Chun Yen Chen, Shiou Ying Cheng, Der Feng Guo, Wen Chau Liu

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

## Abstract

Characteristics of GaN-based light-emitting diodes (LEDs) with 1-D stripe (B-series) and 2-D grid (A-series) Ag metal line patterns are comprehensively studied and reported. Due to the enhanced current spreading capability, as compared to a conventional LED, the significantly reduced forward voltages (>500 mV) of studied A- and B-series devices are obtained under the forward current of 20 mA. Particularly, a very low current coefficient of junction temperature $\text{T}-{\text {j}}$ (0.03°/mA) could be obtained for studied A- and B-series devices which is remarkably superior to the conventional device (0.61°/mA). It means that the undesired thermal effect is nearly negligible in studied devices. Experimentally, based on the less absorption effect of photons from Ag metal lines, the 1-D stripe design (B-series) shows better optical properties than 2-D grid one (A-series). Therefore, based on the appropriate design of transparent 1-D Ag pattern, the improved performance of GaN-based LEDs, including smaller forward voltage, higher light output power, higher external quantum efficiency, higher wall-plug efficiency, and negligible current dependence (wider current operating regime) could be simultaneously attained.

Original language English 7911252 2542-2548 7 IEEE Transactions on Electron Devices 64 6 https://doi.org/10.1109/TED.2017.2691411 Published - 2017 Jun

## All Science Journal Classification (ASJC) codes

• Electronic, Optical and Magnetic Materials
• Electrical and Electronic Engineering