3-D Vision and Intelligent Online Inspection in SMT Microelectronic Packaging: A Review

With the rapid advancements in surface mount technology (SMT), microelectronic packaging products are becoming smaller, denser, and defect-free. This has led to stricter requirements for surface quality inspection. In the realm of industrial visual inspection, there is a growing demand for three-dimensional imaging technology to achieve high-precision and fast image acquisition, as well as for AI-based online inspection models to enhance real-time defect detection. This article primarily focuses on first- and second-level package products for SMT microelectronics and discusses the main optical imaging technologies, analyzing the principles and limitations. Next, this article analyzes the current research status of intelligent detection models based on deep learning in industrial environments and discusses current technical issues in data augmentation, small object learning, and model lightweight. The article also summarizes the characteristics and applications of the latest representative products, comparatively analyzes the gap between developed and developing countries. Finally, this article outlines four major challenges and future research trends in this field, aiming to promote the intelligent evolution of related visual inspection equipment.