Research Status and Progress On Non-Destructive Testing Methods for Defect Inspection of Microelectronic Packaging

In a highly competitive and demanding microelectronics market, non-destructive testing (NDT) technology has been widely applied to defect detection and evaluation of microelectronic packaging. However, the trend of microelectronic packaging toward miniaturization, high-density, ultra-thin, ultra-light and with small chip footprint, poses an urgent demand for novel NDT methods with high-resolution and large penetration depth, which is utilized for internal defect detection and identification of advanced complicated packages. The conventional NDT methods for microelectronic packaging mainly include optical visual inspection, X-ray inspection, active infrared thermography, scanning acoustic microscopy (SAM), atomic force microscopy (AFM), laser Doppler vibration measuring technique, scanning SQUID microscopy (SSM), electrical impedance spectroscopy (EIS), scanning electron microscope (SEM), and so on. This paper aims to provide a review of addressing their basic principles, advantages, limitations and application researches in the field of defect inspection of microelectronic packaging. Moreover, in order to overcome the shortcomings of the existing NDT methods, this paper emphasizes a novel NDT approach, called hybrid ultrasonic-laser digital holographic microscopy (DHM) imaging inspection method, and discusses its basic principle, merits, key techniques, system construction and experimental results in detail. When some key technical problems can be solved in further research, this method will become a potentially promising technique for defect detection and evaluation of advanced complicated packages.