Greetings All, I am looking for the formula to predict DC-Etch readings prior to oxide. I know IPC-MF-150F lists the resistivity of 1 oz. As .162 Ohm-gram/meter^2, however the only formulas I have seen for determining the resistance of a conductor incorporate Rho (resistivity constant) as Ohm-meter. Any and all help is greatly appreciated. Steve Stone Process Engineer Altron, Inc. 978-933-1735 [log in to unmask] ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################