Applications and Practices of Ultrasonic Imaging Technology in Quality Control

  Dr. Gujin Hu

  Chief Scientist, Shaoxing Xinjiyuan Electronic Technology Co., Ltd., China

Abstract：

The semiconductor industry is continuously evolving toward miniaturization, high integration and high precision, driving the rapid popularization of advanced 2.5D and 3D heterogeneous stacking packaging technologies. The complex three-dimensional structures formed by multi-layer stacking and heterogeneous bonding of devices have significantly increased the difficulty of detecting internal latent defects, rendering traditional inspection methods incapable of meeting the high-precision quality control requirements of advanced manufacturing processes. Hidden defects such as wafer bonding voids, 2.5D interposer delamination, 3D stacking interface debonding, microcracks and adhesive layer separation serve as the primary causes of failure for high-end semiconductor devices.

Traditional inspection technologies exhibit prominent limitations in 2.5D and 3D advanced processes. X-ray technology features low recognition accuracy for interface defects of light-element materials including silicon substrates and packaging adhesives, making it difficult to identify subtle interlayer defects in three-dimensional structures. Eddy current inspection only covers the surface layer of devices, leaving extensive blind areas for deep and interlayer defects. Its insufficient accuracy and detection coverage fail to support full-process non-destructive testing, which severely restricts the improvement of yield rate and long-term reliability of high-end chips.

Ultrasonic imaging inspection technology is highly compatible with 2.5D and 3D advanced packaging processes. It fully covers core links including wafer manufacturing, three-dimensional packaging, process monitoring and failure analysis, enabling accurate identification of various three-dimensional latent defects, non-contact high-resolution visual inspection and quantitative analysis. This technology effectively compensates for the shortcomings of traditional testing methods. With mature mass-production application experience, it supports advanced process optimization, new material selection and reliability verification, adapts to the development trend of cutting-edge three-dimensional packaging, effectively breaks through the quality control bottlenecks of high-end semiconductors, and facilitates the high-quality development of the semiconductor industry.

Speaker's Biography: 

Research Fellow and PhD Supervisor at Shanghai Institute of Technical Physics, Chinese Academy of Sciences (CAS), he earned his doctoral degree from CAS. His research focuses on optoelectronic properties of wide-bandgap semiconductors, advanced materials and device physics, as well as fabrication and physical properties of ferroelectric materials.

He has presided over 8 national and provincial-level research programs, and participated in key national initiatives including the National 973 Program, 863 Program, and Major & Key Projects funded by the National Natural Science Foundation of China. He holds 9 authorized invention patents and has published more than 60 SCI-indexed papers.

He serves as a peer reviewer for internationally renowned journals such as Crystal Growth & Design and Applied Physics Letters, alongside the domestic journal Journal of Semiconductors. Dr. Hu boasts profound academic expertise and extensive engineering experience in the inspection and characterization of semiconductor materials and devices.