Page 9 - Nanotechnology an introduction

Chapter Contents

1.1 Definitions and Concepts 2
1.1.1 Working Definitions 2
1.1.2 Towards a Concept System for Nanotechnology 3
1.2 An Ostensive Definition of Nanotechnology 5
1.3 A Brief History of Nanotechnology 5
1.3.1 Ultraprecision Engineering 7
1.3.2 Semiconductor Processing qua Microtechnology 7
1.3.3 Nanoparticles 9
1.4 Biology as Paradigm 10
1.5 Why Nanotechnology? 11
1.5.1 Novel Combinations of Properties 11
1.5.2 Device Miniaturization: Functional Enhancement 13
1.5.3 A Universal Fabrication Technology 14
1.6 Summary 14
1.7 Further Reading 14
Nanotechnology is defined in various ways; a selection of already-published definitions is given, from which it may be perceived that a reasonable consensus already exists. A more formal concept system for nanotechnology is developed,
in which care is taken to use the terms consistently. Nanotechnology is also defined ostensively (i.e., what objects already in existence are called “nano”?), and by its history. The role of biology is introduced as providing a living proof-of-
principle for the possibility of nanotechnology; this has been of historical importance and continues to provide inspiration. Motivations for nanotechnology are summarized.
Keywords: definitions, concept system, ontology, history, ultraprecision engineering, semiconductor processing, nanoparticles, biology, motivation, miniaturization
Nanotechnology is above all a mindset, a way of thinking about the world that is rooted in atomically precise perception. As such, it represents the
apotheosis of man's ceaseless urge to understand the world and use that understanding for practical purposes. Well synonymized as “atomically
precise technology”, it encapsulates the vision of building “our earthly estate” atom-by-atom, controlling architecture, composition and hence
physical properties with atomic resolution. “Hard” nanotechnologists promote a future world in which every artifact (and even food) can be
constructed atom-by-atom from a feedstock such as acetylene, requiring in addition only energy and instructions. A more pragmatic view accepts
that there are many intermediate stages in which partially atomically precise construction can improve existing artifacts and create new ones.
Similarly, the resolute aim of “hard” nanotechnologists is to create productive nanosystems (PN) working with atomic precision—the nanoscale
assemblers that would execute the instructions and build everything we need from the bottom upwards, whereas a more pragmatic view accepts
that while in principle everything can be reproduced and many things imitated via atom-by-atom assembly, in many cases the improvement in
properties or performance would be negligible and a hybrid approach will best serve the needs of humanity. This is particularly likely to be the case
for large artifacts (such as human dwellings or airplanes) and for relatively complex products such as food, which can be quite easily grown
naturally.

In this chapter we shall first look at the basic definitions for nanotechnology, and sketch a concept system (“ontology”) for the field. It is also possible
to define nanotechnology ostensively, according to what is already generally considered to be nanotechnology, and extended by what is envisaged
in the future. A further way of defining it is through its history. We also briefly look at the relation of nanotechnology to biology, which has been a
powerful paradigm for convincing engineers that nanotechnology is possible—nanobiotechnology and bionanotechnology form the topics of
subsequent Chapter 4 and Chapter 11 respectively). General motivations for nanotechnology are considered—“Why nanotechnology?” Attention is
drawn to the appended list of neologisms associated with nanotechnology (Appendix, p. 247).
1.1. Definitions and Concepts

1.1.1. Working Definitions

The simplest definition of nanotechnology is “technology at the nanoscale”. The various definitions currently circulating can be reasonably accurately
thus paraphrased. Obviously, this definition is not intelligible in the absence of a further definition, namely that of the nanoscale. Furthermore,
definitions of components of nanotechnology, such as “nanofiber”, also refer to the nanoscale; indeed every word starting with “nano”, which we can
generically write as “nanoX”, can be defined as “nanoscale X”. Therefore, unless we define “nanoscale”, we cannot therefore properly define
nanotechnology. A rational attempt to do so is made in Chapter 2. Here we note that provisionally, the nanoscale is considered to cover the range
from 1 to 100 nm. Essentially this is a consensus without a strong rational foundation.
A slightly longer but still succinct definition of nanotechnology is simply “engineering with atomic precision”, or “atomically precise technology”
(APT). However, this definition does not explicitly include the aspects of “fundamentally new properties” or “novel” and “unique” that
nanotechnologists usually insist upon, wishing to exclude existing artifacts that happen to be small. These aspects are encapsulated by the US
National Nanotechnology Initiative's declaration that “the essence of nanotechnology is the ability to work at the molecular level, atom-by-atom, to
create large structures with fundamentally new molecular organization … nanotechnology is concerned with materials and systems whose
structures and components exhibit novel and significantly improved physical, chemical, and biological properties, phenomena, and processes due
to their nanoscale size”[123].
The US Foresight Institute gives “nanotechnology is a group of emerging technologies in which the structure of matter is controlled at the nanometer
scale to produce novel materials and devices that have useful and unique properties”. Function is stressed in: “the design, synthesis,
characterization and application of materials, devices and systems that have a functional organization in at least one dimension on the nanometer
scale”. This is emphasized even more strongly in “nanotechnology pertains to the processing of materials in which structure of a dimension of less
than 100 nm is essential to obtain the required functional performance”[36].