Physical mechanism of NBTI relaxation by RF and noise performance of RF CMOS devices

For the first time the RF performance and flicker noise degradation and relaxation as a function of time of RF CMOS devices after negative bias temperature instability (NBTI) stress was reported. By comparing the dc, RF and flicker noise performance, we were able to probe the physical mechanism of NBTI. The relaxation of the degradation involves both fixed charge and interface charge. The magnitudes, time constants and post-stress results all indicate fixed charge leaving the oxide and recombining with interface states play a dominate role in the interface state relaxation.