title: Acoustic Micro Imaging based Reliability Testing and Life Prediction of Electronic Packages
Creators: name: Wang, H
Publisher: name: Liverpool John Moores University
Year: 2027

description: Safety-critical electronics systems and particularly those deployed in autonomous drive and avionics applications are powering a growing need in reliability engineering for system health assessment and prediction of the remaining useful life of electronics systems. As microelectronic packaging technology moves to three-dimensional (3D) packaging with higher integration of functional components, the ever-increasing power density of the chip and the complex multi-layer structures have made the thermal management and heat dissipation more difficult. Due to the mismatch of thermal expansion coefficients of materials, thermal fatigue leads to physical defects such as cracks and delamination, bringing significant impact on the reliability of microelectronic packages. Research shows that the failure rate of flip chip packages which is widely used in high reliability product area increases exponentially with temperature growth. Its failure rate doubled if the operating temperature of electronic components increased by 10℃. According to statistics, Stress concentration results in solder joints becoming the weakest link within flip-chip packaging, with over half of electronic product failures attributable to thermal failure of solder joints. Consequently, thermal failure of solder joints in electronic packaging has emerged as the predominant mode of failure in electronic products. To improve the reliability of the electronic packaging, the structure defects of solder joints should be detected in time, so that we can have enough time to take actions before these defects lead to catastrophic accidents. This research presents three key innovations in developing a novel method for evaluating thermal fatigue damage in electronic packaging: (1) A multi-resolution sparse signal representation (SSR) algorithm based on support matching pursuit (SMP) is developed, enabling adaptive processing of overlapping ultrasonic signals; (2) A novel edge detection algorithm that accounts for edge effects in solder joint imagery was proposed, effectively addressing image quality degradation caused by edge effects during ultrasonic microscopic imaging; (3) A position-dependent parametric failure model is proposed based purely on C-scan image characteristics to accommodate varying stress states of solder joints at different chip locations. These innovations integrate acoustic microscopic inspection technology, finite element simulation, and thermal fatigue damage theory. The experimental results validate the effectiveness of our proposed approaches: The multi-resolution SSR algorithm successfully achieves precise separation of overlapping ultrasonic signals while improving decomposition performance without increasing dictionary size. The position-based failure model accurately predicts the lifespan pattern of solder joints, showing longest life at chip edge centers, gradually decreasing towards both sides, and shortest at corner positions, which aligns well with finite element simulation results and flip-chip packaging failure theories. This research opens new avenues for applying acoustic micro imaging (AMI) in electronic packaging reliability assessment."