We've found the implementation of SPC to be difficult in our circuit board manufacturing facility. Due to the wide of variety of board designs we produce, I think the best way to use valid SPC techniques would be to use a standard test panel. The dissadvantage is that this can be somewhat expensive and intrusive into normal prod'n (you have to stop running normal product so the test panel can be run). Another option is to use standard test patterns that can be printed on the border of regular production panels. This also has a disadvantage since we've found that patterns on the borders of the panel often come out of a process with different characteristices than features on the interior area of the panels. For example, for controlling line widths in etching processes, we've tried to use test patterns (since different lots will have different line width specs) but have found that due to spray pressures, circuitry density, etc. the measurements taken on the panel border don't necessarily correlate well with actual circuit measruements. If anyone has struggled with these problems, we would appreciate some information. My E-mail address is [log in to unmask] Thanks! Dave Hall P.S. - I submitted a request for information on HAL SPC several days ago and received some very helpful responses. Thanks! *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************