Laser Micro Soldering and Soldering Factors

레이저 마이크로 솔더링과 솔더링 인자

  • Hwang, Seung Jun (Department of Materials Science and Engineering, University of Seoul) ;
  • Hwang, Sung Vin (Department of Materials Science and Engineering, University of Seoul) ;
  • Jung, Jae Pil (Department of Materials Science and Engineering, University of Seoul)
  • 황승준 (서울시립대학교 신소재공학과) ;
  • 황성빈 (서울시립대학교 신소재공학과) ;
  • 정재필 (서울시립대학교 신소재공학과)
  • Received : 2020.08.10
  • Accepted : 2020.09.29
  • Published : 2020.09.30


In this paper, the principles, characteristics and recent studies of the laser micro soldering are reviewed. The factors which influence laser micro welding and soldering are also included. Laser soldering is a non-contact process that transfers energy to solder joint by a precisely controlled laser beam. In recent electronics industry, the demands for laser soldering are increasing due to bonding for complex circuits and local heating in micro-joint. In laser soldering, there are several important factors like laser absorption, laser power, laser scanning speed, and etc, which affect laser solderability. The laser absorption ratio depends on materials, and each material has different absorption or reflectivity for the laser beam, which requires fine adjustment of the laser beam. Laser types and operating conditions are also important factors for laser soldering performance, and these are also reviewed.



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