Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect

Zhiyuan Liu; Haicheng Cao; Xiao Tang; Tingang Liu; Yi Lu; Zixian Jiang; Na Xiao; Xiaohang Li

doi:10.1038/s41377-025-01751-y

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Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect

Review

- Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect
- Light: Science & Applications Vol. 14, Issue 2, Pages: 307-332(2025)
- Affiliations：
  
  Advanced Semiconductor Laboratory, Electrical and Computer Engineering Program, CEMSE Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
- Author bio：
  
  Xiaohang Li (xiaohang.li@kaust.edu.sa)
- Funds：
- DOI：10.1038/s41377-025-01751-y
  CLC：
- Received：22 July 2024，
  
  Revised：09 December 2024，
  
  Accepted：2025-01-07，
  
  Published Online：26 January 2025，
  
  Published：28 February 2025
- Accepted：
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Liu, Z. Y. et al. Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect. Light: Science & Applications, 14, 307-332 (2025).
DOI：

Liu, Z. Y. et al. Advanced technologies in InGaN micro-LED fabrication to mitigate the sidewall effect. Light: Science & Applications, 14, 307-332 (2025). DOI： 10.1038/s41377-025-01751-y.

摘要

Abstract

The size of InGaN micro-LEDs is continuously decreasing to meet the demands of various emerging applications

especially in tiny micro-displays such as AR/VR. However

the conventional pixel definition based on plasma etching significantly damages the mesa sidewalls

leading to a severe reduction in efficiency as the micro-LED size decreases. This seriously impedes the development and application of micro-LEDs. In this work

we comprehensively explain the origin of micro-LED sidewall effects and corresponding physical models. Subsequently

we systematically review recent progress in micro-LED fabrication aiming at suppressing sidewall effects. Furthermore

we discuss advancements in micro-LED fabrication with “damage-free” techniques

which hold the potential to fundamentally address the issue of plasma damage in the micro-LED process. We believe this review will deepen the understanding of micro-LED sidewall effects and provide a better insight into the latest associated fabrication technologies for high-efficient InGaN micro-LEDs.

关键词

Keywords

references

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