Page 86 - Visions of the Future Chemistry and Life Science

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Diamond thin films: a twenty-first century
material

Paul W. May

School of Chemistry, University of Bristol, Bristol BS8 1TS, UK

Diamond has some of the most extreme physical properties of any
material, yet its practical use in science or engineering has been limited
due its scarcity and expense. With the recent development of techniques
for depositing thin films of diamond on a variety of substrate materials, we
now have the ability to exploit these superlative properties in many new
and exciting applications. In this paper, we shall explain the basic science
and technology underlying the chemical vapour deposition of diamond
thin films, and show how this is leading to the development of diamond as
a twenty-first century engineering material.

5.1 The diamond in history

Probably more so than any other gemstone, diamonds feature more pre-
dominantly in the history and cultural heritage of the human race. They
were prized for their scarcity for centuries, and still remain a symbol of
wealth and prestige to this day. The word diamond comes from the Greek
adamas, meaning indestructible. Diamonds were first mined in India over
4000 years ago, but the modern diamond era only began in 1866, when huge
diamond deposits were discovered in Kimberley, South Africa, creating a
huge rush of European prospectors. The wealth this created helped to
underwrite the British Empire, and changed the fates of many African
countries.
Apart from their appeal as gemstones, diamonds possess a remarkable

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