Prognostic Capabilities for Field Effect Transistors (FET)

Shrinking semiconductor process geometries (130 nm and below) are increasingly subject to performance, lifetime, and reliability-limiting effects that can cause hard-to-diagnose intermittent failures. One of the most serious emerging reliability problems is called Negative Bias Temperature Instability (NBTI). NBTI is a p-MOSFET degradation mechanism that causes increasing threshold voltage (VT) shifts. Such shifts, if large enough, cause intermittent performance problems in electronic modules, including timing errors and gain accuracy errors. Working with IBM’s Trusted Foundry semiconductor process, Ridgetop will design, develop, and fabricate an NBTI prognostic circuit that measures the VT shift in a p-MOSFET and reports its state-of-health. The p-FET Prognostic Chip will be fabricated in the IBM 130 nm process, with Options for the IBM 90 nm and 65 nm processes. Ridgetop will also provide generic serial data output capability, and as an Option, an I2C-bus interface for use in important military applications, such as the Joint Strike Fighter.