Study of a Low-Temperature Bonding Process for a Next-Generation Flexible Display Module Using Transverse Ultrasound

횡 초음파를 이용한 차세대 플렉시블 디스플레이 모듈 저온 접합 공정 연구

  • Ji, Myeong-Gu (School of NID Fusion Nano Micro Robot System, Seoul Nat'l Univ. of Science and Technology) ;
  • Song, Chun-Sam (R&D Center. Inc., LTS(Laser Total Solution)) ;
  • Kim, Joo-Hyun (School of Mechanical Engineering, Kookmin Univ.) ;
  • Kim, Jong-Hyeong (School of Mechanical Design and Automation Engineering, Seoul Nat'l Univ. of Science and Technology)
  • 지명구 (서울과학기술대학교 NID융합기술대학원) ;
  • 송춘삼 ((주)엘티에스 기획실) ;
  • 김주현 (국민대학교 기계시스템공학부) ;
  • 김종형 (서울과학기술대학교 기계설계.자동화공학부)
  • Received : 2011.07.20
  • Accepted : 2012.01.26
  • Published : 2012.04.01


This is direct bonding many of the metal bumps between FPCB and HPCB substrate. By using an ultrasonic horn mounted on an ultrasonic bonding machine, it is possible to bond gold pads onto the FPCB and HPCB at room temperature without an adhesive like ACA or NCA and high heat and solder. This ultrasonic bonding technology minimizes damage to the material. The process conditions evaluated for obtaining a greater bonding strength than 0.6 kgf, which is commercially required, were 40 kHz of frequency; 0.6MPa of bonding pressure; and 0.5, 1.0, 1.5, and 2.0 s of bonding time. The peel off test was performed for evaluating bonding strength, which was found to be more than 0.80 kgf.


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