Triggering voltage for post-breakdown random telegraph noise in HfLaO dielectric metal gate metal-oxide-semiconductor field effect transistors and its reliability implications

We report a triggering voltage V_trig for observing gate leakage current (I_g) random telegraph noise (RTN) in the post-breakdown regime of HfLaO dielectric metal gate stacks. V_trig, the onset voltage to observe RTN in degraded dielectrics, is highly dependent on breakdown hardness, which is controlled by the leakage current compliance (I _gl). This dependence is qualitatively analyzed using a percolation dilation model, where generation of additional traps either at different energy levels or spatial locations gives lower V_trig at higher I _gl. The magnitude of V_trig can be used as a direct indication of the impact of RTN on the performance of the transistor at device level, when V_trig is evaluated by comparing with the device operating voltage.