Well-Conditioned MOSFET Surface Potential Equation for Cryogenic Temperatures and Its Analytical Approximation

In this article, we present a well-conditioned surface potential equation (SPE) explicitly considering the incomplete impurity ionization for planar MOSFETs at cryogenic temperatures. By extending the methodology employed in the PSP model, we derive an analytical approximation. The proposed formalism demonstrates a high level of accuracy, which is validated through numerical solutions across a temperature range spanning from 500 K down to 4 K.