1063-7397/04/3304- © 2004 MAIK “Nauka /Interperiodica”
Russian Microelectronics, Vol. 33, No. 4, 2004, pp. 195–205. Translated from Mikroelektronika, Vol. 33, No. 4, 2004, pp. 243–255.
Original Russian Text Copyright © 2004 by Sidorov, V’yurkov, Orlikovsky.
The modeling and simulation of nanoscale ﬁeld-
effect transistors (FETs) are important for both scien-
tiﬁc and engineering reasons, enabling the designer to
improve device performance. Ballistic and quasiballis-
tic FETs made in GaAs or other III–V semiconductors
have been efﬁciently treated by particle simulation in
which the Monte Carlo (MC) method was applied to
carrier scattering and injection, an approach commonly
known as Monte Carlo simulation. With modern ballis-
tic silicon FETs, the MC simulation procedure should
be modiﬁed to include quantum effects.
This paper is concerned with the MC simulation of
silicon FETs subject to quantum effects. The focus is on
silicon-on-insulator (SOI) metal–oxide–semiconductor
FETs (MOSFETs), which appear to represent the most
promising way to further extend the silicon technology
into the nanoscale area. A schematic diagram of the
SOI MOSFET is shown in Fig. 1. The reader is also
referred to our previous study .
CLASSICAL MONTE CARLO
SIMULATION OF MOSFETs
When to Employ Monte Carlo Simulation?
Micrometer- and submicrometer-channel silicon
FETs were ﬁrst studied within ﬂuid models; common
examples are the drift–diffusion model and the modi-
ﬁed ﬂuid model, the latter allowing for carrier heating.
With nanoscale channels (
m), these approaches
do not work because the carrier distribution function in
the channel is essentially nonequilibrium. The mini-
mum channel length for which ﬂuid models are valid is
estimated as follows. In silicon the saturation of elec-
Monte Carlo Simulation of Nanoscale SOI MOSFETs
A. A. Sidorov, V. V. V’yurkov, and A. A. Orlikovsky
Institute of Physics and Technology, Russian Academy of Sciences, Moscow, Russia
Received January 12, 2004
—A comparative review is presented of the current research on the quantum-mechanical and classical
Monte Carlo simulation of SOI MOSFETs. A quantum-mechanical simulation method is proposed whereby the
energy of transverse channel quantization is represented by a correction term. A newly developed simulation
program, called BALSOI, is outlined. A comparison is made between the results of a 2D classical Monte Carlo
simulation and those obtained by the quantum-mechanical method. It is observed that the differences are much
smaller than what one might expect. This ﬁnding is explained as due to the considerable effect of the space
charge, which is mainly governed by the classical, longitudinal motion of carriers through the channel. An ana-
lytical formula is derived for the effect of channel quantization on the gate–channel capacitance. The strength
of tunneling current through a short-channel transistor in the off state is considered.
Schematic diagram of the SOI MOSFET.