Geometry dependence of gate oxide breakdown evolution [MOSFET]

The effects of geometrical arrangement of MOSFETs on breakdown (BD) evolution in ultrathin gate oxide have been studied. Specific attention was paid to the impact of heat confinement in narrow MOSFETs on the BD evolution from soft BD to hard BD. It is found that, based on a numerical simulation, the thermal effect, which is the main driving force of catastrophic BD, is more severe in narrow MOSFETs than wide MOSFETs, which is in agreement with the degradation rate measured from their respective BD transients.