Application of Wafer Bonding in Advanced Packaging

   Mr. Weijia Cai 

   CTO, WuShi Microelectronics (Suzhou) Co.. Itd.

Abstract: :

Wafer bonding technology has transcended the limitations of the traditional MEMS field, becoming one of the core processes driving the development of advanced packaging. This presentation will systematically outline its technical value and innovation pathways across multidimensional application scenarios.

In the MEMS field, wafer bonding achieves reliable isolation of micro-mechanical structures through hermetic or protective packaging, effectively enhancing the environmental adaptability and long-term stability of devices, and has become a standard packaging solution for products such as sensors and actuators. With the surge in demand for 2.5D/3D packaging, temporary bonding technology enables efficient support and precise alignment of thin wafers through reversible adhesion, supporting the process implementation of TSV middle-end processes and 3D stacking structures, thus serving as the cornerstone of high-density integrated packaging. In SOI (Silicon-on-Insulator) and POI (Piezo-on-Insulator) material systems, direct bonding technology constructs high-quality heterogeneous interfaces through molecular-level fusion, optimizing the electrical performance and thermal management characteristics of devices, and is widely applied in scenarios such as RF devices and power modules. Hybrid bonding technology achieves vertical interconnection between pixel arrays and logic circuits in CIS backside-illuminated packaging through the synergistic bonding of metal and dielectric layers, significantly improving imaging quality and system integration. Facing the frontier exploration of 3D advanced packaging, wafer bonding technology is breaking through traditional 2D planar limitations. Through multi-layer wafer stacking and heterogeneous integration, it enables high-density interconnection and functional fusion between chips, providing key support for applications such as high-performance computing and artificial intelligence.

This presentation aims to present the full evolution of wafer bonding from a back-end auxiliary process to a core manufacturing segment by systematically reviewing the technical aspects of the aforementioned typical application scenarios, and to explore its development prospects in future directions such as heterogeneous integration and 3D system-level packaging.

Speaker's Biography: 

Mr. Cai Weija has been dedicated to the semiconductor industry since 2006, specializing in the field of wafer bonding technology. He previously worked at SUSS MicroTec, an internationally renowned lithography and bonding equipment company. During his nineteen years at SUSS, he served as Bonding Product Specialist for a long time, which gave him the opportunity to stand at the forefront of international technological innovation and dedicate himself to promoting the development and application of wafer bonding technology. He has been deeply involved in the construction of semiconductor R&D lines for numerous renowned domestic research institutions and higher education institutions, facilitating the transformation of scientific research achievements in China's semiconductor industry into industrial applications. He has also led and participated in multiple wafer bonding process capability building and development projects for chip manufacturing factories, assisting various enterprises in refining and developing wafer bonding technology, or achieving technological breakthroughs from scratch, and establishing stable production systems related to wafer bonding.

Currently, he has joined Wushi Microelectronics, an emerging domestic wafer bonding equipment supplier, serving as CTO (Chief Technology Officer). After joining Wushi, Mr. Cai Weija continues to uphold the service philosophy of being "guided by customer needs," dedicated to providing customers with more flexible, reliable, and efficient wafer bonding solutions, striving to meet customers' diverse needs, and further enhancing domestic equipment and process technical capabilities in this field.