Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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p-Type Activation of AlGaN-based UV-C Light-Emitting Diodes by Hydrogen Removal using Electrochemical Potentiostatic Activation

전기화학적 정전위 활성화를 사용한 수소 제거에 의한 AlGaN기반의 UV-C 발광 다이오드의 p-형 활성화

  • Lee, Koh Eun (LG Innotek Co. Ltd.) ;
  • Choi, Rak Jun (LG Innotek Co. Ltd.) ;
  • Kumar, Chandra Mohan Manoj (Department of Materials Science & Engineering, Chonnam National University) ;
  • Kang, Hyunwoong (School of Semiconductor and Chemical Engineering, Jeonbuk National University) ;
  • Cho, Jaehee (School of Semiconductor and Chemical Engineering, Jeonbuk National University) ;
  • Lee, June Key (Department of Materials Science & Engineering, Chonnam National University)
  • Received : 2021.12.09
  • Accepted : 2021.12.14
  • Published : 2021.12.30
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Abstract

AlGaN-based UV-C light-emitting diodes (LEDs) were applied for p-type activation by electrochemical potentiostatic activation (EPA). The p-type activation efficiency was increased by removing hydrogen atoms through EPA treatment using a neutral Mg-H complex that causes high resistance and low conductivity. A neutral Mg-H complex is decomposed into Mg- and H+ depending on the key parameters of solution, voltage, and time. The improved hole carrier concentration was confirmed by secondary ion mass spectroscopy (SIMS) analysis. This mechanism eventually improved the internal quantum efficiency (IQE), the light extraction efficiency, the leakage current value in the reverse current region, and junction temperature, resulting in better UV-C LED lifetime. For systematic analysis, SIMS, Etamax IQE system, integrating sphere, and current-voltage measurement system were used, and the results were compared with the existing N2-annealing method.

AlGaN 기반 UV-C 발광다이오드(LEDs)에 전기화학적 전위차 활성화(EPA)에 의한 p-형 활성화를 진행하였다. 높은 저항과 낮은 전도도를 유발하는 중성 Mg-H의 복합체의 수소원자를 EPA를 이용하여 제거하여 p-형 활성화 효율을 높였다. 중성 Mg-H 복합체는 주요 매개 변수인 용액, 전압, 시간에 의해 Mg-과 H+로 분해되며, 2차 이온질량 분광법(SIMS) 분석을 통하여 개선된 정공 캐리어의 농도를 확인할 수 있었다. 이 메커니즘은 결국 내부 양자효율(IQE)의 증가, 광 추출 효율 향상, 역 전류 영역의 누설전류 값 개선, 접합 온도 개선 등을 이루어 결과적으로 UV-C LED의 수명을 향상시켰다. 체계적인 분석을 위해 SIMS, Etamax IQE 시스템, 적분구, 전류-전압(I-V) 측정 등을 사용하였으며, 그 결과를 기존의 N2-열 처리 방법과 비교 평가하였다.

Keywords

Acknowledgement

본 연구는 LG이노텍 및 전남대학교 연구년교수 연구비(과제번호 : 2021-1446)지원에 의하여 수행된 연구이며, 또한 본 연구는 2019년도 교육부의 재원으로 한국기초과학지원연구원 국가연구시설장비진흥센터의 지원을 받은 기초과학연구역량강화사업 핵심연구지원센터 조성 지원 과제에서 에너지 융복합 전문핵심 연구지원센터를 조성하여 수행된 연구결과임(과제번호 2019R1A6C1010024).

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