Invitation to lectures by colleagues from Taiwan
The lectures will be held on 29.10. from 9 a.m. to 11 a.m. in the meeting room of the dean's office B17/432:
Old electroplating technology for new joining applications in microelectronics
Chih-Ming Chen
Department of Chemical Engineering, National Chung Hsing University, Taichung 402202, Taiwan
Understanding Interesting Phenomena at the Joints of Electronic Products: Thermodynamic and Kinetic Driving Forces
Sinn-wen Chen
Department of Chemical Engineering, National Tsing Hua University

Understanding Interesting Phenomena at the Joints of Electronic Products: Thermodynamic and Kinetic Driving Forces
Sinn-wen Chen1,2,3
1 Department of Chemical Engineering, National Tsing Hua University
2College of Semiconductor Research, National Tsing Hua University
2 High Entropy Materials Center, National Tsing Hua University
The driving forces of reactions can be classified as thermodynamics and kinetics. The thermodynamic driving force refers to the tendency for a system to reach an equilibrium state with lowest Gibbs free energy through reaction. Phase diagrams are the most concise way to describe phase equilibria of materials. Phase equilibria information gives insight into the thermodynamic driving forces. Examples of peculiar reactions observed in the electronic joints, such as peculiar melting, peculiar melting rates, whisker growth, are discussed and their driving forces are understood through their related phase diagrams.
Old electroplating technology for new joining applications in microelectronics
Chih-Ming Chen
Department of Chemical Engineering, National Chung Hsing University, Taichung 402202, Taiwan
Joints play a vital role in microelectronics, serving as the media for signal transmission and mechanical support. Electroplating is an old technology for metal deposition, but it has found new applications in advanced electronic packaging due to cost-effectiveness and scalable flexibility. In this talk, two examples will be given to demonstrate the application of electroplating in the joints. The first one is the electrodeposition of a Sn/Bi bi-layer for low-temperature soldering application. The Sn/Bi bi-layer can melt at low temperatures (below 180 °C) within a very short time to form a robust solder joint. The second one is the electrodeposition of Cu with distinct grain sizes for Cu-Cu direct bonding. Driven by the difference in grain size, cross-interface grain growth occurs significantly along the bonding interface, achieving a robust solder-free joint.