Considerations for DD Simulation at Cryogenic Temperature
Seonghoon Jin, Anh-Tuan Pham, Woosung Choi, Mohammad Ali Pourghaderi, Uihui Kwon, Dae Sin Kim
Abstract
We discuss device models employed in the drift-diffusion simulation of MOSFET transistors at deep cryogenic temperatures. We report potential issues of the commonly used models (the Philips unified mobility model, the high field saturation model, the incomplete ionization model, and the quantization model) at low temperatures and how to resolve the issues. In addition, we present a band tail model to capture the subthreshold slope saturation at low temperatures. We also discuss how to obtain the initial solution and perform the bias ramping to avoid convergence issues. As an application, we study the temperature-dependent operation of a gate-all-around transistor down to 4 K.