Sorry Sharon, You sent this to the wrong Richard. Rick Hudson. [log in to unmask] (602) 436-7154 (602) 436-7100 Fax > -----Original Message----- > From: Sharon Polmanteer [SMTP:[log in to unmask]] > Sent: Thursday, December 10, 1998 9:46 AM > To: [log in to unmask] > Subject: > > To Richard Haynes > > Hi Richard, > > We have been having intermittent trouble with (what most people call) pits > in electrolytic Cu plating. The location of these pits is always at the > resist sidewall, they are always perfectly round, as are caused by > bubbles. > Popular opinion is that this has been caused by oxygen induction via > filtration system. All four of the copper tanks we have are different in > physical construction and to have all the tanks cavitating air at one time > seems an outside possibility to me. However, we have asked for vendor > guidance in new filtration system setup. > > Your comment on cathode-hydrogen evolution and oxygen evolution interested > me and I have some questions: > > A vendor told me that there is no hydrogen evolution in acid copper as it > is > 100% efficient. I don't know. > > What physical characteristics do annodes exhibit when polizaration > occurs? > Is there extremely irregular surface? > > Can high chloride concentration also cause polizaration, i.e. 144 ppm? > > When I pull a sample in a glass flask and look at the amount of bubbles > present, is turbidity the condition I'm looking for or the size/quantity > of > the bubbles present? I don't know what amount of bubbles should cause > concern. Sorry if these are dumb questions. > > Thanks very much > Sharon > > ################################################################ > TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" > section for additional information. > For technical support contact Hugo Scaramuzza at [log in to unmask] or > 847-509-9700 ext.312 > ################################################################ ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################