Showing papers by "Yi Cui published in 2003"

High Performance Silicon Nanowire Field Effect Transistors

Abstract: Silicon nanowires can be prepared with single-crystal structures, diameters as small as several nanometers and controllable hole and electron doping, and thus represent powerful building blocks for nanoelectronics devices such as field effect transistors. To explore the potential limits of silicon nanowire transistors, we have examined the influence of source-drain contact thermal annealing and surface passivation on key transistor properties. Thermal annealing and passivation of oxide defects using chemical modification were found to increase the average transconductance from 45 to 800 nS and average mobility from 30 to 560 cm 2 /V‚s with peak values of 2000 nS and 1350 cm 2 /V‚s, respectively. The comparison of these results and other key parameters with state-of-the-art planar silicon devices shows substantial advantages for silicon nanowires. The uses of nanowires as building blocks for future nanoelectronics are discussed.

Nanowire Crossbar Arrays as Address Decoders for Integrated Nanosystems

Abstract: The development of strategies for addressing arrays of nanoscale devices is central to the implementation of integrated nanosystems such as biological sensor arrays and nanocomputers. We report a general approach for addressing based on molecular-level modification of crossed semiconductor nanowire field-effect transistor (cNW-FET) arrays, where selective chemical modification of cross points in the arrays enables NW inputs to turn specific FET array elements on and off. The chemically modified cNW-FET arrays function as decoder circuits, exhibit gain, and allow multiplexing and demultiplexing of information. These results provide a step toward the realization of addressable integrated nanosystems in which signals are restored at the nanoscale.

Nanowires as Building Blocks for Nanoscale Science and Technology

Abstract: The field of nanotechnology represents an exciting and rapidly expanding research area that crosses the borders between the physical, life and engineering sciences [1, 2]. Much of the excitement in this area of research has arisen from recognition that new phenomena and unprecedented integration density are possible with nanometer scale structures. Correspondingly, these ideas have driven scientists to develop methods for making nanostructures. In general, there are two philosophically distinct approaches for creating small objects, which can be characterized as top-down and bottom-up. In the top-down approach, small features are patterned in bulk materials by a combination of lithography, etching and deposition to form functional devices. The top-down approach has been exceedingly successful in many venues with microelectronics being perhaps the best example today. While developments continue to push the resolution limits of the top-down approach, these improvements in resolution are associated with a near exponential increase in cost associated with each new level manufacturing facility. This economic limitation and other scientific issues with the top-down approach have motivated efforts worldwide to search for new strategies to meet the demand for nanoscale structures today and in the future [3–5].