Page 10 - Nanotechnology an introduction

In all such definitions, there is the implicit meaning that, as for any technology, the end result must be of practical use. A dictionary definition of
nanotechnology is “the design, characterization, production and application of materials, devices and systems by controlling shape and size in the
nanoscale”[1]. An alternative definition from the same dictionary is “the deliberate and controlled manipulation, precision placement, measurement,
modeling and production of matter in the nanoscale in order to create materials, devices, and systems with fundamentally new properties and
functions”[1]. The emphasis on control is particularly important: it is this that distinguishes nanotechnology from chemistry, with which it is often
compared. In the latter, motion is essentially uncontrolled and random, within the constraint that it takes place on the potential energy surface of the
atoms and molecules under consideration. In order to achieve the desired control, a special, nonrandom eutactic environment needs to be
available. How eutactic environments can be practically achieved is still being vigorously discussed. Finally, a definition of nanotechnology
attempting to be comprehensive is “the application of scientific knowledge to measure, create, pattern, manipulate, utilize or incorporate materials
and components in the nanoscale”. This underlines the idea of nanotechnology as the consummation of Stage 4 in the sequence of technological
revolutions that marks the development of human civilization (Table 12.1 in Chapter 12).
It is sometimes debated whether one should refer to “nanotechnology” or “nanotechnologies”. The argument in favor of the latter is that
nanotechnology encompasses many distinctly different kinds of technology. But there seems to be no reason not to use “nanotechnology” in a
collective sense, since the different kinds are nevertheless all united by striving for control at the atomic scale. Both terms are, in fact, legitimate.
When one wishes to emphasize diverse applications, the plural form is appropriate. The singular term refers above all to the mindset or attitude
associated with the technology.

1.1.2. Towards a Concept System for Nanotechnology

Objects are perceived or conceived. The properties of an object (which may be common to a set of objects) are abstracted into characteristics.
Essential characteristics (feature specifications) typically falling into different categories (e.g., shape, color) are combined as a set to form a
concept; this is how objects are abstracted into concepts, and the set of essential characteristics that come together as a unit to form a concept is
called the intension. The set of objects abstracted into a concept is called the extension. Delimiting characteristics distinguish one concept from
another. Concepts are described in definitions and represented by designations. The set of designations constitutes the terminology. Concepts are
organized into concept systems. A concept system is often called an ontology (which literally means the science of being, but lately is often used in
a more restricted sense, namely that of the study of categories).
Figure 1.1 shows (part of) an ontology for nanotechnology. To the right of the diagram one has products—an axis of tangible objects in order of
increasing complexity: materials, devices and systems. To the left of the diagram one has processes. Note the relationships between metrology
and fabrication (nanomanufacturing, usually abbreviated to nanofacture, also called atomically precise manufacturing, APM) and devices. An
atomic force microscope is used to measure nanoscale features; every measuring instrument is necessarily a device; and pushing nano-objects
around with a needle is the basis of bottom-to-bottom fabrication (see Section 8.3).

Figure 1.1 A concept system (ontology) for nanotechnology. Most of the terms would normally be prefixed by “nano” (e.g., nanometrology, nanodevice). A dashed line merely signifies that if the superordinate concept contributes, then
the prefix must indicate that (e.g., bionanodevice, bionanosystem). Biology may also have some input to nanomanufacture (nanofacture), inspiring, especially, self-assembly processes. Not shown on the diagram is what might be called
“conceptual nanotechnology”, or perhaps better (since it is itself a concept), “virtual nanotechnology”, which means the (experimental and theoretical) scrutiny of engineering (and other, including biological) processes at the nanoscale in
order to understand them better; that is, the mindset or attitude associated with nanotechnology.
Especially the leaves of the tree might be associated with some ambiguity regarding their extensions. For example, devices can be characterized
by the nature of their working medium: electrons, photons, etc. Yet many devices involve more than one medium: for example,
nanoelectromechanical devices are being intensively researched as a way of achieving electronic switching; optoelectronic control is a popular
way of achieving photonic switching; and photochemistry in miniaturized reactors involves both nanophotonics and nanofluidics.
Table 1.1 describes a few of the concepts and their intensions and extensions. At the time of writing, the terminology of nanotechnology is still
being intensively debated within national standards organizations as well supranational bodies such as the Comité Européen de Normalisation
(CEN) and the International Standards Organization (ISO), hence no attempt has been made to be comprehensive here.
Table 1.1 Some nano concepts and their intensions and extensions
Intension Concept Extension
One or more external dimensions in the nanoscale Nano-object Graphene, fullerene
One or more geometrical features in the nanoscale Nanomaterial A nanocomposite
Automaton with information storage and/or processing embodiments in the nanoscale Nanodevice Single electron transistor
1.2. An Ostensive Definition of Nanotechnology

An ostensive definition of current nanotechnology can be constructed from the most popular topics (Table 1.2), essentially extensions in the sense