The scanning acoustic microscope (SAM) is an important tool for development of improved molded and flip chip packages. The SAM used for integrated circuit inspection is a hybrid instrument with characteristics of both the Stanford SAM and the C-scan recorder. This chapter presents the historical development of SAM for integrated circuit package inspection, SAM theory, and analysis considerations. Case studies are presented to illustrate the practical applications of SAM. Other non-destructive imaging tools are briefly discussed, as well as SAM challenges and methods including spectral signature analysis and GHz-SAM.
This chapter describes three approaches for 3D hot-spot localization of thermally active defects by lock-in thermography (LIT). In the first section, phase-shift analysis for analyzing stacked die packages is performed. The second example employs defocusing sequences for the localization of resistive electrical shorts in 3D architectures, and the third operates in cross sectional LIT mode to investigate defects in the insulation liner of Through Silicon Vias. All three approaches allow for a precise localization of thermally active defects in all three spatial dimensions to guide subsequent high-resolution physical analyses.