[paper] Compact Schottky-barrier CNTFET Modeling

Manojkumar Annamalai and Michael Schroter

Compact formulation for the bias dependent quasi-static mobile charge in Schottky-barrier CNTFETs IEEE Transactions on Nanotechnology (2021)

DOI: 10.1109/TNANO.2021.3116694

CEDIC, Technische Universität Dresden (D)

Abstract: Carbon nanotube (CNT) field-effect transistors (FETs) are promising candidates for future high-frequency (HF) system-on-chip applications. Understanding and modeling mobile charge storage on CNTs is therefore essential for device optimization and circuit design. A physics-based compact analytical formulation is presented that enables an accurate approximation of the mobile charge in Schottky-barrier CNTFETs over the practically relevant bias range for HF circuit design. The formulation is C∞ continuous and yields accurate results also for the capacitances. The new formulation has been verified for both ballistic and scattering dominated carrier transport by employing device simulation, which was calibrated to experimental data from multi-tube CNTFETs.

Fig: Band diagram in a CNTFET along the axial direction (left red arrow) and, with applied gate bias, along the radial direction perpendicular to the gate (right blue arrow).

Acknowledgments: The authors would like to thank Dr. S. Mothes, formerly with CEDIC, for valuable discussions regarding the device simulator. This project was financially supported in part by the German National Science Foundation (DFG SCHR695/6-2).