Gate oxide reliability projection to the sub-2 nm regime

The important components of reliability projection are investigated. Acceleration parameters are obtained for a 1.6 nm oxide with a soft breakdown criterion. Based on the physical percolation model, the voltage scaling factor for time to breakdown is found to increase with lower voltage, explaining the experimental observation of 6.7 ± 0.4 dec V^-1 for the 1.6 nm oxide. The distribution of breakdown times is shown to be sensitive to thickness variation across the test wafer, and a Weibull slope of 1.38 ± 0.1 was obtained. The temperature dependence of the time to breakdown was found to be non-Arrhenius and to have a slope of 0.02 dec °C^-1. Using these parameters, the 1.6 nm oxide was found to have a 10 year lifetime with a 100 ppm failure rate for 1.3 V operation at 100 °C. Our understanding of soft breakdown is described as well as an investigation of device operation after soft breakdown, which may further improve the reliability projection.