Design for Stress

The bathtub curve is a frequently used model to describe the lifetime behavior of electronic systems. Typically, it is considered as an approximation, but a sufficiently good one. Nevertheless, looking at dielectric materials used in semiconductor devices, one can derive the bathtub curve based on physics and mathematics.Following this rationale, a design concept and product development model is established that considers this physical and mathematical background. It optimizes the bathtub curve of a device. That means one can derive products with less early failures and lower constant failure rate, while still keeping costs and production efforts under control.This is a structured, systematic approach to reduce early failures, control quality targets, and to ensure the products’ performance over lifetime.