Internal defects inspection of TSV 3D package based on thermal distribution analysis

A small aperture, fine pitch, and high aspect ratio have been the characteristics of through silicon via (TSV) 3D packaging technology. Thus, the requirements of TSV quality are becoming higher and higher. In order to improve the reliability of TSV 3D packaging, it is necessary to find an effective method to discover the internal defect of TSVs. Based on the view that intact TSVs and defective ones will exhibit different external features under thermal-electric coupling excitation, an internal defect inspection method through identifying the external feature pattern is proposed. The simulation result shows a significant difference in the temperature distribution between intact TSVs and those with some typical defects. By contrast, the differences between the intact TSV and the TSV with gaps, bottom cavity, or filling deletion are 1, 2.11, and 6.83 degrees C, respectively. Then, the experiment is carried out, and the defect is recognized via external temperature characteristics caused by the internal defects of TSVs. The good agreement between experimental validation and simulation results shows that the proposed method is feasible for TSV internal defect detection applications.