Ultra-thin gate dielectrics: they break down, but do they fail?

We study breakdown in high-quality 2-7 nm gate dielectrics, and find that soft breakdown becomes more likely for thinner oxides and for oxides stressed at lower voltages. For 2 nm oxides, an increase in gate noise is the only precise indication of soft breakdown. For many applications, devices should remain functional with the level of gate noise we have observed, after soft breakdown.