Critical
parameters in hot filament chemical vapor deposition of diamond films
on tool steel substrates with CrN interlayers
Gowri M (Gowri, M.), Li H (Li, H.), Kacsich T (Kacsich, T.), Schermer
JJ (Schermer, J. J.), van Enckevort WJP (van Enckevort, W. J. P.), ter
Meulen JJ (ter Meulen, J. J.)
Surface and Coatings Technology 201 (2007) 4601-4608
Abstract:
The accomplishment of adherent and continuous diamond coatings on tool
steel substrates with CrN interlayers is determined by many key
parameters such as appropriate surface finish, interlayer thickness,
substrate temperature and system pressure. A detailed study is carried
out to probe the effect of these parameters on diamond nucleation and
growth. Substrates with different surface finishes are prepared by
electrical discharge machining (EDM) and CrN interlayers of various
thicknesses are deposited onto these substrates by arc plating. Samples
with a CrN interlayer of 2.5 mu m are found to provide a continuous
diamond film at a low pressure value of about 5 mbar. Nonetheless, the
process window for obtaining such diamond layers is small, which
results in limited reproducibility.