We present a physics-based circuit-compatible model for pH-sensitive field-effect transistors based on two-dimensional (2D) materials. The electrostatics along the electrolyte-gated 2D-semiconductor stack is treated by solving the Poisson equation including the Site-Binding model and the Gouy-Chapman-Stern approach, while the carrier transport is described by the drift-diffusion theory. The proposed model is provided in an analytical form and then implemented in Verilog-A, making it compatible with standard technology computer-aided design tools employed for circuit simulation. The model is benchmarked against two experimental transition-metal-dichalcogenide (MoS2 and ReS2) based ion sensors, showing excellent agreement when predicting the drain current, threshold voltage shift, and current/voltage sensitivity measurements for different pH concentrations.
@article{arxiv.2109.06585,
title = {Compact Modeling of pH-Sensitive FETs Based on Two-Dimensional Semiconductors},
author = {Tarek El Grour and Francisco Pasadas and Alberto Medina-Rull and Montassar Najari and Enrique G. Marin and Alejandro Toral-Lopez and Francisco G. Ruiz and Andrés Godoy and David Jiménez and Lassaad El-Mir},
journal= {arXiv preprint arXiv:2109.06585},
year = {2021}
}