Design by Topology Optimization and Performance Test of Ultrasonic Bonding Module for Flip-Chip Packaging

초음파 플립칩 접합 모듈의 위상최적화 설계 및 성능 실험

  • Kim, Ji Soo (Dept. of Energy and Environmental System Engineering, University of Seoul) ;
  • Kim, Jong Min (Dept. of Energy and Environmental System Engineering, University of Seoul) ;
  • Lee, Soo Il (Dept. of Mechanical and Information Engineering, University of Seoul)
  • 김지수 (서울시립대학교 에너지환경시스템공학과) ;
  • 김종민 (서울시립대학교 에너지환경시스템공학과) ;
  • 이수일 (서울시립대학교 기계정보공학과)
  • Received : 2012.12.06
  • Accepted : 2012.12.17
  • Published : 2012.12.31


Ultrasonic bonding is the novel packaging method for flip-chip with high yield and low-temperature bonding. The bonding module is a core part of the bonding machine, which can transfer the ultrasonic energy into the bonding spot. In this paper, we propose topology optimization technique which can make new design of boding modules due to the constraints on resonance frequency and mode shapes. The designed bonding module using topology optimization was fabricated in order to evaluate the bonding performance and reliable operation during the continuous bonding process. The actual production models based on the proposed design satisfied the target frequency range and ultrasonic power. The bonding test was performed using flip-chip with lead-free Sn-based bumps, the results confirmed that the bonding strength was sufficient with the designed bonding modules. Also the performance degradation of the bonding module was not observed after the 300-hour continuous process with bonding conditions.


Supported by : 중소기업청


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