Issues In Ramping Advanced Packaging

Multi-die assemblies require significantly more test data than a monolithic chip. Thermal mismatch between different layers can cause warping, which puts stress on the bonds that connect those layers, resulting in failures during testing. The big problem is that traditional daisy-chained test approaches cannot pinpoint where problems are occurring. Instead, they provide a go/no-go for the entire system. Jack Lewis, chief technologist at Modus Test, talks with Semiconductor Engineering about how to obtain data at critical points, how to isolate it from other data, and how much data is required to identify real and latent defects.