Mr Casale, Thanks for your suggestion of using 2 coating runs. Am I right to presume that to eliminate pinholes in Chromium, apart from coating twice, the thickness should be 100nm to be sufficiently thick to eliminate pinholes? Mr. Jeffrey Mun Pun YUE 余文彬 Division of Bioengineering E3A-07-02, Nanobioanalytics Lab 7 Engineering Drive 1 National University of Singapore Singapore 117574 Tel: (65) 65166482, Fax: (65) 68723069 E-mail: g0500396@nus.edu.sg -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of David Casale Sent: Tuesday, March 20, 2007 2:35 AM To: General MEMS discussion Subject: RE: [mems-talk] Pin holes in evaporated Chromium, Titanium and Gold Pin holes are pretty common in evaporated chrome. We evap chrome on glass pretty often, and we often do two coating runs if we want to eliminated pinholes. Pinholes are much more likely to happen if the chamber and or the substrate is dirty. For instance, you are much more likely to have pinholes if you evap a single 1000 angstrom film of chrome than if you do two 500 angstrom coatings. Cleanliness is next to godliness ;)