World Journal of Nano Science and Engineering, 2012, 2, 171-175 http://dx.doi.org/10.4236/wjnse.2012.24022 Published Online December 2012 (http://www.SciRP.org/journal/wjnse) New Model for Drain and Gate Current of Single-Electron Transistor at High Temperature Amine Touati, Samir Chatbouri, Nabil Sghaier, Adel Kalboussi Laboratory of Microelectronics and Instrumentation, Faculty of Sciences of Monastir, University of Monastir, Monastir, Tunisia Email: Amine.Touati@istls.rnu.tn Received May 28, 2012; revised June 6, 2012; accepted July 3, 2012 ABSTRACT We propose a novel analytical model to describe the drain-source current as well as gate-source of single-electron tran- sistors (SETs) at high temperature. Our model consists on summing the tunnel current and thermionic contribution. This model will be compared with another model. Keywords: Single-Electron Transistor (SET); Master Equation; Orthodox Theory; Tunnel Current; Thermionic Current; SIMON 1. Introduction The phenomenal success of semiconductor electronics during the past three decades was based on the scaling down of silicon field effect transistors (MOSFET). The most authoritative industrial forecast, the International Technology Roadmap for Semiconductors (ITRS) [1] predicts that this exponential progress of silicon MOS- FETs and integrated circuits will continue at least for the next 15 years (“Moore’s Law”) [2]. However, prospects to continue the Moore law, a very important device: the single-electron transistor was first suggested in 1985 and first implemented two years later. This device attracted much attention because of their nano feature size and less power consumption. Moreover SETs are suitable for several applications such as memories, multiple-valued logic (MVL)… due to the discrete number of electrons in a coulomb island. SETs characteristics are very different from those of MOSFETs. In both of them, electrostatic effects are dominant, but, due to the existence of Coulomb blockade; electrons are not so free to move from source to drain, due to of tunnel junctions. The Coulomb blockade effect: that is the electrostatic repulsion experienced by an elec- tron approaching a small negatively charged region, lim- its the number of electrons in the island. As a result, for given values of gate and drain voltages, only a range of charge is possible for tunneling. Our day extensive research has been conducted on fabrication, design, and modeling of SET, that has also been an active area. Monte Carlo simulation has been widely used to model SETs. SIMON [3] and MOSES [4] are two most popular SET simulators for circuit analysis and systems containing more than a few SETs but vali- dated in ambient temperature range. Several SET ana- lytical models, each of them based on the orthodox the- ory, can notably name the models proposed for metallic SETs by the following:  Uchida et al. [5] proposed an analytical SET model for resistively symmetric devices (R S = R D ) and valid for DS V eC   , later Inokawa et al. [6] extended this model to asymmetric SETs but does not account for the background charges effect.  Recently a compact analytical model (named MIB) [7] for SET device, which is applicable for 3 DS V eC   and wide-range of temperature, and valid for single/ multiple gate symmetric/asymmetric device, is taken that the only one direction flow to minimize the num- ber of exponential terms. MIB model can be used for both digital and analog SET circuit design and for both pure SET and hybrid CMOS-SET circuit simula- tion. C Σ represents the total capacitance of the SET-island: 1 S D G G C C C C C  2     (1) C G1 , C G2 , C D and C S represent the capacitances of first gate, second gate (when exists), tunnel drain and tunnel source junctions respectively. Two conditions ensure that the transport of charges through the metallic island is governed by: 1) Charging the island with an additional charge takes the time Δt = R T C, which is the RC-time constant of the quantum dot. 2) The charging energy required to add a single elec- tron with charge e to the quantum dot is: ΔE C = e²/C Σ . The system will respect Heisenberg’s uncertainty relation: Copyright © 2012 SciRes. WJNSE