National Center for Design of
Biomimetic Nanoconductors
Marco Saraniti
Contact:
Marco Saraniti is an Associate Professor in the Departments of Electrical and Computer Engineering and Biological, Chemical, and Physical Sciences at the Illinois Institute of Technology. His research interests focus mainly on computational electronics applied to the simulation of semiconductor devices and biological structures. His recent scientific work covers the following fields: (a) development of Monte Carlo and Cellular Automaton techniques for 2D and 3D physical simulation of semiconductor devices, (b) simulation and engineering of semiconductor devices, and (c) development of numerical methods for the modeling and simulation of membrane proteins.
Research
Marco Saraniti worked for more than a decade on the development of numerical methods for the particle-based simulation of semiconductor devices. The software developed by his group is being used by several researchers for the design and characterization of a variety of semiconductor devices based on different materials. In particular, Dr. Saraniti developed innovative algorithms both for the dynamics (Saraniti et al., 2000) of charged particles in in-homogeneous systems and the accurate and efficient modeling of the electrostatic interactions (Saraniti et al., 1996) within those systems. During the last three years, Dr. Saraniti developed a research activity on bioelectronics, focusing mainly on the development of methodology for the particle-based simulation of membrane proteins in ionic solutions and on the design of hybrid bio-electronic sensors that exploit the functionality of biological ion channels. His participation to the activities of the Center for the Design of Biomimetic Nanoconductors will therefore focus on these topics, which he will develop in strict collaboration to the other investigators of the center. A detailed description of the above mentioned activities follows.
Methodology Development: P3M force field scheme As a first step toward a unified modeling approach to be applied to hybrid systems based on membrane proteins and man-made solid-state devices, M. Saraniti developed a force field scheme that is compatible with the geometric and electrical boundary conditions of hybrid bio-electronic devices (Aboud et al., 2004). The adopted approach extends and validates the original P3M method of Hockney (Hockney and Eastwood, 1988) by using a highly efficient real-space 3D Poisson solver based on the iterative multi-grid method (Brandt, 1977; Hackbusch, 1985). Within this scheme, the force on an individual ion is divided into a smoothly varying long-range component and a short-range one. The long-range interaction accounts for the force due to the collective ionic population and the electrical boundary conditions imposed on the device, while the short-range inter-particle interactions result from the coulombic and van der Waals forces between close charges. The long range particle-mesh force is obtained by assigning the charge density to the points of a discrete grid, solving Poisson's equation, and differentiating the potential.
In order to validate the proposed force-field scheme, the thermodynamic properties of an electrolytic solution were calculated under equilibrium conditions as a function of concentration, and were compared to values obtained with analytic approximations and experimental results, where available. Furthermore, the equilibrium thermodynamic properties of an ionic solution were determined. This involves the calculation of the radial distribution function (RDF) (McQuarrie, 2000) which relates the probability of finding a pair of ions at a specific separation to the probability in a homogeneous distribution at the same density (Allen and Tildesley, 1987). The RDF for KCl and NaCl electrolytic solutions were validated by showing agreement with the numerical solution of the Ornstein-Zernike equation (Barthel et al., 1998) solved using the hypernetted chain approximation (HNC) as a closure relation (Hansen and McDonald, 1976).
Design of Hybrid Biosensors: This project, starting now its second phase, involves a large group of researchers from several national and European universities. Dr. Saraniti is working in collaboration with Dr. Goodnick and Dr. Thornton from the Electrical Engineering Department of Arizona State University, and is involved in the modeling and simulation of the solid-state portion of a hybrid biosensor based on ion channels.
The collaboration with Saraniti provides the Center not only with his specific expertise in electrostatics, but also connection to another experimental group with strengths complementary to ours.
Related Publications
M. Saraniti, Y. Hu, and S.M. Goodnick, "Particle-based full-band approach for fast simulation of charge transport in Si, GaAs, and InP," VLSI DESIGN, vol. 15, pp.743-750, 2002.
M. Saraniti, J. Tang, S.M. Goodnick, S.J. Wigger, "Numerical challenges in particle-based approaches for the simulation of semiconductor devices," Mathematics and Computers in Simulation, vol. 65, pp. 501-508, March 2003.
S. Wilk, M. Goryll, G. M. Laws, T. J. Thornton, S. M. Goodnick, M. Saraniti, J. M. Tang, and R. S. Eisenberg, "Teflon coated silicon apertures for supported lipid bilayer membranes", Applied Physics Letters, Vol. 85, No. 15, pp. 3307-3309, 2004
S. Aboud, D. Marreiro, M. Saraniti, and R. Eisenberg, "A Poisson P3M Force Field Scheme for Particle-Based Simulations of Ionic Liquids," Journal of Computational Electronics, Vol. 3, No. 2, pp. 117-133, 2004.
P. Chiney, J. Branlard, M. Saraniti and S. Goodnick, "Full-band particle-based analysis of device scaling foe 3D tri-gate FETs", Journal of Computational Electronics, 2005.
Related Links
Marco Saraniti's Electrical and Computer Engineering Profile