Identification of Soft Failure Mechanisms Triggered by ESD Stress on a Powered USB 3.0 Interface

The objective of this work is to identify electrostatic discharge (ESD) related soft failure mechanisms early in the product life cycle. We compare different methods of injecting ESD stress into USB 3.0 interfaces which are regularly exposed to ESD stress during end-user operation. A directional injection method is applied which is compatible to high-speed line operation and capable to provide quantitative information about failure levels. Soft failure modes are investigated depending on the operational state of the system under test. Five typical categories of soft failure modes of a USB 3.0 interface could be identified. A method to use the characterization data gained from system verification boards for final system design is presented.