Abstract
Analyzing scan chain failures is challenging without dedicated test hardware. Traditional solutions like ATE testers and compact diagnosis tools have significant drawbacks: they're expensive, require complex hardware customization and proprietary software licenses, and need substantial lab space. This paper presents a cost-effective alternative: a portable, flexible, and fully customizable bench-top scan chain testing system that easily integrates with fault isolation tools. Using an off-the-shelf embedded development tool, we replicated the complete scan chain testing process—from pattern generation to test vector transmission/reception and results comparison. The system reduces costs by approximately 200-fold compared to traditional solutions. We validated our approach by analyzing a device with marginal and frequency-dependent stuck-at-scan failures. Using DALS (Dynamic Analog Laser Stimulation), we successfully localized the defect and confirmed it through mechanical delayering, FIB cross-sectioning, and SEM imaging.
