2024

Vol.30 No.4

Editorial Office

Review

  • Journal of the Microelectronics and Packaging Society
  • Volume 30(3); 2023
  • Article

Review

Journal of the Microelectronics and Packaging Society 2023;30(3):102-110. Published online: Nov, 9, 2023

Scarf Welding of Thin Substrates and Evaluation of the Tensile Properties

  • Beomseok Kang, Jeehoo Na, Myeong-Jun Ko, Minjeong Sohn, Yong-Ho Ko, and Tae-Ik Lee
    Micro-Joining Center, Joining R&D Group, Korea Institute of Industrial Technology, Incheon 21999, Korea
Corresponding author E-mail: tilee@kitech.re.kr
Abstract

This paper introduces scarf welding process of thin substrates using flexible laser transmission welding (f-LTW) technology. We examined the behavior of tensile strength relative to the scarf angle for flexible applications. Thin plastic substrates with the thickness of less than 100 μm were bonded and a jig to form a slope at the edge of the substrate was developed. By developing the scarf welding process, we successfully created a flexible bonding technology that maintains joint’s thickness after the process. The tensile strength of the joint was assessed through uniaxial test, and we found that the tensile strength increases as the slope of bonding interface decreases. By conducting stress analysis at the bonding interface with respect to the slope angle, design factor of bonding structure was investigated. These findings suggest that the tensile strength depends on the geometry of the joint, even under the same process conditions, and highlights the significance of considering the geometry of the joint in welding processes.

Keywords thin substrate, scarf welding, laser bonding, stress analysis

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