Effect of the Tolerance Parameters of the Horn on the Vibration of the Thermosonic Transverse Bonding Flip Chip System

횡 방향 플립 칩 초음파 접합 시 혼의 공차변수가 시스템의 진동에 미치는 영향

  • 정하규 (서울시립대학교 기계정보공학과 대학원) ;
  • 권원태 (서울시립대학교 기계정보공학과) ;
  • 윤병옥 (서울시립대학교 기계정보공학과)
  • Published : 2009.02.15

Abstract

Thermosonic flip chip bonding is an important technology for the electronic packaging due to its simplicity, cost effectiveness and clean and dry process. Mechanical properties of the horn and the shank, such as the natural frequency and the amplitude, have a great effect on the bonding capability of the transverse flip chip bonding system. In this research, two kinds of study are performed. The first is the new design of the clamp and the second is the effect of tolerance parameters to the performance of the system. The clamp with a bent shape is newly designed to hold the nodal point of the flip chip. The second is the effect of the design parameters on the vibration amplitude and planarity at the end of the shank. The variation of the tolerance parameters changes the amplitude and the frequency of the vibration of the shank. They, in turn, have an effect on the quantity of the plastic deformation of the gold ball bump, which determined the quality of the flip chip bonding. The tolerance parameters that give the great effect on the amplitude of the shank are determined using Taguchi's method. Error of set-up angle, the length and diameter of horn and error of the length of the shank are determined to be the parameters that have peat effect on the amplitude of the system.

Keywords

References

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