A unification of interface-state generation and hole-injection for hot-carrier-injection stress in low and high-voltage NMOSFET

To characterize hot-carrier-injection degradation, a typical reaction-diffusion model has been used in low-voltage NMOSFETs with only hot-electron-injection. In this paper, an improved reaction-diffusion model of hole-injection and electron-injection induced interface-state generation, with a lower time exponent, is proposed in high-voltage NMOSFETs. The dynamics of hot-carrier-injection are considered with simulation, experiment and theory. Hole-injection induced by an additional high-electric-field outside the gate is found to be also responsible for degradation mechanism. Based on a better understanding of the mechanism of HV NMOSFETs, the modified reaction-diffusion model for hot-carrier-injection stress involves hole-injection.