Modeling of charge to breakdown QBD for thin gate oxide MOS devices

A new breakdown model based on anode hole injection for calculating Q_BD for thin oxides is presented. Based on the model, the breakdown strength (Q_BD) of thin oxides is predicted for various oxide voltages. The dielectric field, which is closely related to oxide degradation and lifetime has been calculated correctly using our model. The correction in oxide voltage due to poly and flatband voltages is properly taken into account in determining the electric field across the oxide. The poly depletion effect of a MOS device has been investigated by simulating the quasi static C-V curve for different oxide thicknesses and polysilicon gate doping concentrations using the physical device simulator Medici. Moreover, the model accounts for the quantum yield in silicon in computing the hole current injected from the anode. The results obtained from the proposed model agrees well with the experimental Q_BD results for a thickness range of 45 to 13 nm