-This paper presents the modeling of Single Electron Transistor (SET) based on Physical model of a device and its equivalent circuit. The physical model is derived from Schrodinger equation. The wave function of the electrode is calculated using Hartree-Fock method and the quantum dot calculation is obtained from WKB approximation. The resulting wave functions are used to compute tunneling rates. From the tunneling rate the current is calculated. The equivalent circuit model discuss about the effect of capacitance on tunneling probability and free energy change. The parameters of equivalent circuit are extracted and optimized using genetic algorithm. The effect of tunneling probability, temperature variation effect on tunneling rate, coulomb blockade effect and current voltage characteristics are discussed.

In this paper, single electron transistor is modeled using Master Equation (ME) approach. In our scheme the steady state Master Equation was expressed, in which the resultant value is necessary for the current calculation. A ME for the probability distribution of electrons in the SET dot is obtained from the stoachastic process, allowing the calculation of device characteristics. Helmholtz's free energy is considered to determine the transport of electrons through a SET device. Work done by voltage source and free energy change is calculated to get improved IV characteristics of SET.