September 2003
Scale Deposits and the Scale of the Problem
In the past year. we have been contacted by
European and USA companies that are
experiencing an increase in scale deposits inside
their etching machincs. The problem seems to
be a common one. but in one case the problem
was new to the company.
Scale is a real challenge in PCM as it appears in
various locations within the etching machine. It
forms on surfaces. then it flakes off them and
consequently blocks spray nozzles and pipes.
These blockages reduce the flow rate of the
etchat both uniformly and randomly, thus
affecting the control of part dimensions.
Professor David Allen and Dr. Sue Impey, School of Industrial and Manufacturing Science, Cranfield University
