Introduction to Nanotechnology

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METHODS OF MEASURING
PROPERTIES
3.1. INTRODUCTION
The current revolution in nanoscience was brought about by the concomitant
development of several advances in technology. One of them has been the prog-
ressive ability to fabricate smaller and smaller structures, and another has been the
continual improvement in the precision with which such structures are made. One
widely used method for the fabrication of nanostructures is lithography, which
makes use of a radiation-sensitive layer to form well-defined patterns on a surface.
Molecular-beam epitaxy, the growth of one crystalline material on the surface of
another, is a second technique that has become perfected. There are also chemical
methods, and the utilization of self-assembly, the spontaneous aggregation of
molecular groups.
Since the early 1970s the continual advancement in technology has followed
Moore’s law (Moore 1975) whereby the number of transistors incorporated on a
memory chip doubles every year and a half. This has resulted from continual
improvements in design factors such as interconnectivity efficiency, as well as from
continual decreases in size. Economic considerations driving this revolution are the
need for more and greater information storage capacity, and the need for faster and
broader information dispersal through communication networks. Another major
Znhoduction to Nanotechnology, by Charles P. Poole Jr. and Frank J. Owens.
ISBN 0471-07935-9. Copyright 0 2003 John Wiley & Sons, Inc.
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