A SPICE Compact Model for Ambipolar 2-D-Material FETs Aiming at Circuit Design

• Published in: IEEE transactions on electron devices 2021-06, Vol.68 (6), p.3096-3103
• Main Authors: Ahsan, Sheikh Aamir, Singh, Shivendra Kumar, Mir, Mehak Ashraf, Perucchini, Marta, Polyushkin, Dmitry K., Mueller, Thomas, Fiori, Gianluca, Marin, Enrique G.
• Format: Article
• Language: English
• Subjects: 2-D materials; Analog circuits; Charge carrier processes; circuit and compact modeling; Circuit design; Current carriers; Digital electronics; Electric potential; Electrostatics; Fermi-Dirac statistics; Field effect transistors; field-effect transistor (FET); Integrated circuit modeling; Logic gates; Narrowband; Semiconductor devices; SPICE; Two dimensional materials; Two dimensional models; Verilog-A
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2021.3074357

We report a charge-based analytic and explicit compact model for field-effect transistors (FETs) based on 2-D materials (2DMs), for the simulation of 2DM-based analog and digital circuits. The device electrostatics is handled by invoking 2-D density of states and Fermi-Dirac statistics that are later combined with the Lambert-W function and Halley's correction to eventually obtain explicit expressions for the electron and hole charges, which are exploited in the calculation of drift-diffusion currents for both carriers. Furthermore, the charge model is extended to obtain characteristics of 2DM-based negative capacitance FETs. The model is benchmarked against experimental MoS 2 FET measurements and experimental ambipolar characteristics of narrowband-gap materials, such as black phosphorus. Its soundness for SPICE circuit-level simulations is also demonstrated.