Consistency of the Two Component Composite Modeling Framework for NBTI in Large and Small Area p-MOSFETs

Consistency of the recently proposed deterministic composite modeling framework for Negative Bias Temperature Instability (NBTI) in large area devices is verified for stochastic NBTI in small area devices. The framework has two independent and uncoupled components, interface trap generation (ΔV
_IT
), and hole trapping in pre-existing defects (ΔV
_HT
). The time evolution of mean threshold voltage shift (ΔV
_T
), from multiple ultra-fast measurements in small area devices under diverse stress and recovery conditions, is predicted by the deterministic composite framework. It is shown that although the physical mechanism of NBTI remains the same as the device area is scaled, there can be significant differences in the relative ΔV
_IT
and Δ V
_HT
contribution to ΔV
_T
between large and small area devices, which can alter the overall model parameters. A stochastic simulation framework, fully consistent with the deterministic framework, is developed, which is shown to predict experimentally measured mean time evolution of ΔV
_T
in small area devices.