Modeling the non-uniform distribution of interface traps

The incorporation of total ionizing dose (TID) effects into surface-potential-based compact models requires calculating the dependence of surface potential ( ψ
_s
) on radiation-induced defect densities. This dependence is obtained through the introduction of the oxide trapped charge (N
_ot
) and the interface trap (N
_it
) areal densities into the surface potential equation (SPE). In this work we present an approach for introducing a non-uniform energy distribution of interface traps into calculations of ψ
_s
. The approach is verified experimentally through comparisons with capacitance vs. voltage (C-V) characteristics of metal-oxide-semiconductor (MOS) capacitors exposed to ionizing radiation.