Upcoming Physics Challenges for Device Modeling

Science and technology at the nanoscale size offer today fundamental challenges in the field of device modeling. In this paper we document the growing interest of academies, institutions, and industries and the present impact on the market, and discuss different design strategies that have been proposed and/or implemented, aimed at the practical realization of innovative nanodevices. Few main examples of ideas and devices, namely ion-channel nano-biosensors, biomimetic sensors, molecular devices, solid-state components for quantum computation, nanotube electronics, and non-volatile nanomemories, are also revised. 1 Making it small makes the difference There is a large consensus among scientists about the fact that when something (material, device, system or process) is developed on a truly nanometric scale (1-10 nm) its properties and behavior become different from those observed on the sub-micron mesoscale (10-100 nm). For this reason nanoscience and nanotechnology nowadays offer challenging problems from the point of view of fundamental research, and new fields for innovative industrial applications, both supported by many major funding initiatives worldwide. Many scientists, mainly physicists, chemists, and materials and electronics engineers have explored so far the new opportunities offered by nanoscience and technology. Furthermore, since the typical space and time scales involved in nanoscience are in common with molecular biology, an impressive merging of knowledge is taking place, and collaborations are being established with the molecular-biology community. Two different approaches can be identified within this melting crucible. The engineer’s approach is aimed at designing nanoscale elements and devices that should mimic, or even exceed, the performances of biological structures by making rational choices of materials, rather than accepting those that evolution has provided, and by using the modern principles of engineering design. The biologist’s approach, based on the concept that the biological design solutions are likely to be close to the optimum for the environment in which they have evolved, is focused on removing the components of SIMULATION OF SEMICONDUCTOR PROCESSES AND DEVICES Vol. 12 Edited by T. Grasser and S. Selberherr September 2007 169