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