Advanced Materials Characterization for Microvia Failure Analysis
Advanced Materials Characterization for Microvia Failure Analysis
Wednesday, October 7, 2026: 4:00 PM
Summary:
This paper presents a correlative workflow for stacked microvia failure analysis in HDI printed circuit boards, showing that no single technique is sufficient for reliable root-cause analysis. The workflow begins with non-destructive X-ray screening to locate suspect microvias, then uses mechanical cross-sectioning and optical microscopy to reveal overall geometry. SEM/EDS provides higher-resolution imaging and chemical mapping to identify voids, cracks, oxidation, and contamination at critical Cu interfaces. EBSD adds crystallographic information, showing that some interfaces recrystallize into continuous Cu and are not necessarily weak points. FIB-prepared TEM lamellae, followed by TEM, STEM-EDS/EELS, and nano-beam diffraction, provide nanoscale confirmation of interface integrity, local chemistry, and crystallographic defects. A barcode scan engine case study demonstrates how this multiscale approach distinguishes benign variation from true failure-relevant features such as interfacial separation, localized contamination, voiding, and crystallographic mismatch. The main conclusion is that robust microvia failure analysis requires linked structural, chemical, and crystallographic evidence across length scales to determine where failure initiated and why.
This paper presents a correlative workflow for stacked microvia failure analysis in HDI printed circuit boards, showing that no single technique is sufficient for reliable root-cause analysis. The workflow begins with non-destructive X-ray screening to locate suspect microvias, then uses mechanical cross-sectioning and optical microscopy to reveal overall geometry. SEM/EDS provides higher-resolution imaging and chemical mapping to identify voids, cracks, oxidation, and contamination at critical Cu interfaces. EBSD adds crystallographic information, showing that some interfaces recrystallize into continuous Cu and are not necessarily weak points. FIB-prepared TEM lamellae, followed by TEM, STEM-EDS/EELS, and nano-beam diffraction, provide nanoscale confirmation of interface integrity, local chemistry, and crystallographic defects. A barcode scan engine case study demonstrates how this multiscale approach distinguishes benign variation from true failure-relevant features such as interfacial separation, localized contamination, voiding, and crystallographic mismatch. The main conclusion is that robust microvia failure analysis requires linked structural, chemical, and crystallographic evidence across length scales to determine where failure initiated and why.