Wafer Bonding and Hybrid Bonding Technologies: From Fundamentals to Frontier Applications

   Prof. Chenxi Wang

   Professor，Harbin Institute of Technology                                                                                                           

Abstract:

In recent years, wafer direct bonding technology, which requires no intermediate layers, has gained significant attention and is widely used in areas such as single-crystal thin-film composite substrates, MEMS packaging, and heterogeneous integration. Conventional silicon fusion bonding, requiring excessively high temperatures, tends to cause thermal diffusion and thermal stress issues between dissimilar wafers, making it difficult to meet the diverse and high-density integration demands of the post-Moore era. Therefore, developing low-temperature or even room-temperature bonding technologies for heterogeneous materials has become an inevitable trend. This course introduces the fundamental principles and evolution of wafer bonding, with a focus on the technological development and core differences between ultra-high vacuum surface activated bonding (SAB) and plasma activated bonding (PAB). In addition, the course provides a discussion on the bumpless hybrid bonding technology for 3D integration, covering key challenges such as high-precision Cu/SiO2 alignment, interface defect control, and low-temperature processing. Covering the innovation path from conventional wafer bonding to advanced hybrid bonding, this course explores strategies to overcome thermal budget limitations, offering technical support for future high-performance heterogeneous integration.

Lecturer Biography:

Dr. Chenxi Wang is a full professor at Harbin Institute of Technology (HIT), a recipient of the National First-Class Course Award (China), and received Ph.D. from The University of Tokyo. His research interests include wafer bonding, heterogenous/hybrid chip bonding, 3D integration and packaging, and joining of medical materials. He was a Research Fellow of the Japan Society for the Promotion of Science (JSPS) and participated in the JST-CREST (Core Research for Evolutionary Science and Technology). After returning to China, he has led four projects supported by the National Natural Science Foundation of China (NSFC), and undertaken over 20 provincial and industrial research projects. He has published more than 140 SCI/EI papers and received seven Best Paper Awards from international conferences. He holds 17 authorized invention patents. He serves as a technical committee member of ICEPT (International Conference on Electronic Packaging Technology), a senior member of IEEE, and a senior member of the Chinese Mechanical Engineering Society (CMES). His honors include the Chinese Government Award for Outstanding Self-Financed Students Abroad, the Dean's Award from the School of Engineering, the University of Tokyo, and the First Prize of Natural Science Award of Heilongjiang Province. In teaching, he has won multiple first prizes in provincial and university-level teaching competitions. He was the supervising instructor of the champion team (Grand Prize, first place) in the “Challenge Cup” National College Student Extracurricular Academic and Technological Works Competition. He has led four educational reform projects and co-authored two textbooks.