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Ag Sintering Die Attach Technology for Wide-bandgap Power Semiconductor Packaging

Wide-bandgap 전력반도체 패키징을 위한 Ag 소결 다이접합 기술

  • Min-Su Kim (Advanced Joining & Additive Manufacturing R&D Department / Micro-Joining Center, Korea Institute of Industrial Technology (KITECH)) ;
  • Dongjin Kim (Advanced Joining & Additive Manufacturing R&D Department / Micro-Joining Center, Korea Institute of Industrial Technology (KITECH))
  • 김민수 (한국생산기술연구원 접합적층연구부문 / 마이크로조이닝센터) ;
  • 김동진 (한국생산기술연구원 접합적층연구부문 / 마이크로조이닝센터)
  • Received : 2023.02.13
  • Accepted : 2023.02.22
  • Published : 2023.03.30

Abstract

Recently, the shift to next-generation wide-bandgap (WBG) power semiconductor for electric vehicle is accelerated due to the need to improve power conversion efficiency and to overcome the limitation of conventional Si power semiconductor. With the adoption of WBG semiconductor, it is also required that the packaging materials for power modules have high temperature durability. As an alternative to conventional high-temperature Pb-based solder, Ag sintering die attach, which is one of the power module packaging process, is receiving attention. In this study, we will introduce the recent research trends on the Ag sintering die attach process. The effects of sintering parameters on the bonding properties and methodology on the exact physical properties of Ag sintered layer by the realization 3D image are discussed. In addition, trends in thermal shock and power cycle reliability test results for power module are discussed.

전기차용 전력변환모듈의 성능향상 요구와 종래의 Si 전력반도체의 한계 극복을 위해 차세대 전력반도체인 wide-bandgap (WBG) 기반 전력반도체로의 전환이 가속화되고 있다. WBG 전력반도체로의 전환을 위해 전력변환모듈 패키징 소재 역시 높은 고온 내구성을 요구받고 있다. 전력변환모듈 패키징 공정 중 하나인 Ag 소결 다이접합 기술은 종래의 고온용 Pb 솔더링의 대체 기술로 주목받고 있다. 본 논문에서는 Ag 소결 다이접합 기술 관련 최신 연구동향에 대해 소개하고자 한다. 소결 다이접합 공정 조건에 따른 접합부 특성을 비교하고 Ag 소결층의 3차원 이미지 구현에 따른 다공성 Ag 소결 접합부의 물성 측정 방법론에 대해 고찰하였다. 또한 열충격 및 파워사이클 신뢰성 평가 연구동향을 분석하였다.

Keywords

Acknowledgement

본 논문은 한국생산기술연구원 기관주요사업 "제품생산 유연성 확보를 위한 뿌리공정기술 개발(KITECH EO23-0008)" 의 지원으로 수행한 연구입니다.

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