Microcrack Detection and Localization in Laminated Packaging Structures Using Superlets and Lamb Wave Static Components

In electronic packaging, early micro crack detection is crucial for maintaining the long-term reliability of devices. This study specifically addresses the detection of microcracks in laminated die-attachment regions, considering the impact of crack orientation on detection efficacy. This study introduces a two-step approach for detecting and localizing microcracks in thin laminated packaging structures. The first step involves the application of Superlets technology to transform time-frequency data into high-resolution images that reveal fault characteristics. The second step utilizes the static component of Lamb waves for accurate crack localization. A theoretical model is developed to analyze the interaction between microcracks and Lamb waves, shedding light on the critical role of the static component in localization. Finite element simulations, combined with advanced signal processing techniques, validate the effectiveness of this approach. Additionally, ultrasonic experiments on typical packaging structures, confirm the practical applicability of Superlets for detecting damage in practice. The integration of Superlets technology with Lamb wave analysis, as demonstrated through our finite element model, not only shows significant potential for improving microcrack detection and localization but also serves as a case study for the application of this technology in practical scenarios.