Compact Modeling Chapter 7

A Circuit Compatible Analytical Device Model for Nanowire FET Considering Ballistic and Drift-Diffusion Transport

Authors: B.C. Paul, R. Tu, S. Fujita, M. Okajima, T. Lee and Y. Nishi

Affilation: Toshiba America Research, United States

Pages: 687 - 690

Keywords: nanowire compact model, Ballistic transport, Drift Diffusion transport

Abstract:
In this paper, we present a simplified circuit compatible analytical device model of nanowire FET for both ballistic and drift-diffusion transport, which can be efficiently used in any conventional circuit simulator like SPICE. The developed model is also verified with experimental result. The closed form expressions for I-V and C-V characteristics in terms of terminal potentials (Vg, Vd and Vs) are obtained by decoupling surface potential (bias dependent term) from the Fermi integral (used to express the electrostatics of the device). In order to do that we divide the operating region into two; (1) sub-threshold and (2) super-threshold, and subsequently use series expansion to achieve an analytical expression for channel charge, QNW. This analytical charge expression is then used to obtain a closed form I-V and C-V characteristics of the device considering both ballistic and drift-diffusion transport. The model is further validated by experimentally measured I-V characteristics of a fabricated nanowire PFET device. The above analytical model will hence, greatly facilitate the simulation of large nanowire circuits using conventional circuit simulators.

ISBN: 1-4200-6184-4
Pages: 732
Hardcopy: $139.95