Abstract
A mechanism of degradation and breakdown in high-k/metal gate transistors was investigated. Based on the electrical test, physical analysis, and modeling results, we propose that the breakdown path formation/evolution in the interfacial SiO2 layer is associated with the growth of an oxygen-deficient filament facilitated by the grain boundaries of the overlaying high-k film. The model allows reproducing SILC temperature dependency and its exponential increase from the fresh through soft and progressive breakdown phases.