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In article <C1F58B.MF4@brunel.ac.uk> mt90dac@brunel.ac.uk (Del Cotter) writes:
>What colour is amorphous diamond film?  Just curious; we had a lecture on
>phase equilibria today and the question came up.
>
>Any other gee-whiz facts on the manufacture/properties/applications of ADF?
>
>   ', ,','    |       Del Cotter       mt90dac@brunel.ac.uk      |    ', ,','  


I think you mean "amorphous diamond-like films", a.k.a.
"hydrogenated amorphous carbon", "alpha-C:H", etc.

In thin layers, i.e., 50-500 nm, they can be
transparent with yellow-to-brown tint, but depending on
the deposition conditions, either almost clear or
metallic-looking films can also be made.

They are easily deposited by high-frequency discharges
(100 kHz - 2.45 GHz) from any hydrocarbon gas at rather
low pressures (0.001 - 10 Torr).

They are VERY hard (8-9 on the Mohs' scale (Si is 7,
various carbides 8-9, diamond 10), VERY smooth,
electrically insulating, chemically resistant,
hydrophobic, are very good gas transport barriers, etc
etc. Fun to work with, too.

People have used such films for tool, lens, and optical
fiber coatings, medical implant coatings, transfer layers 
in high-resolution lithography, to fabricate 
ultraminiature stressor elements in quantum structure 
studies, etc. There is a CRC book on the subject.

Hope it helps.

Tony
tony2@cc.bellcore.com