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<p>In this work, we simulated and modeled silicon quantum dot based single electron transistor (SET). We simulated the device using non-equilibrium Green’s function (NEGF) formalism in transport direction coupled with Schrodinger equation in transverse directions. The characteristics of SET such as Coulomb blockade and Coulomb diamonds were observed. We also present a new efficient model to calculate the current voltage (IV) characteristics of the SET. The IV characteristic achieved from the model are very similar to those from simulations both in shape and magnitude. The proposed model is capable of reproducing the Coulomb diamond diagram in good agreement with the simulations. The model, which is based on transmission spectrum, is simple, efficient and provides insights on the physics of the device. The transmission spectrum at equilibrium is achieved from simulations and given as input to the model. The model then calculates the evolved transmission spectra at non-equilibrium conditions and evaluates the current using Landauers formula.</p>

We concentrate on Molecular-FET as a device and present a new modular framework based on VHDL-AMS. We have implemented different Molecular-FET models within the framework. The framework allows comparison between the models in terms of the capability to calculate accurate -characteristics. It also provides the option to analyze the impact of Molecular-FET and its implementation in the circuit with the extension of its use in an architecture based on the crossbar configuration. This analysis evidences the effect of choices of technological parameters, the ability of models to capture the impact of physical quantities, and the importance of considering defects at circuit fabrication level. The comparison tackles the computational efforts of different models and techniques and discusses the trade-off between accuracy and performance as a function of the circuit analysis final requirements. We prove this methodology using three different models and test them on a 16-bit tree adder included in Pentium 4 that, to the best of our knowledge, is the biggest circuits based on molecular device ever designed and analyzed.

Applications like biosequence alignment are currently addressed using traditional technology at the price of a huge overhead in terms of area and power dissipation. Nanoarrays are expected to outperform current limits especially in terms of processing capabilities. The purpose of this work is to assess the real terms of these expectations. Our contribution deals with: (i) a new model for nanowire FETs used to evaluate transistor’s essential performance; (ii) a new switch-level simulator for nanoarray structure used to evaluate its switching activity; (iii) a nanoarray implementation for biosequence alignment based on a systolic array and the modeling of its essential performance based on (i) and (ii); (iv) the evaluation of the potential improvement of the nanoarray-based systolic structure with respect to an equivalent CMOS one in terms of processing capabilities, area, and power dissipation. Depending on the possible technological scenario, the performance of nanoarray is impressive, especially considering the density achievable in terms of processing per unit area. A wide solution space can be explored to find the optimal solution in terms of trading power and performance considering the technological limitations of a realistic implementation.