Hi Jorge! Silver/Platinum finishes will oxidize/sulfidize over time and become very nonsolderable. A very aggressive flux (ANSIJ-STD-004 type H) is typically used when this oxidized/sulfidized condition exists. It is my opinion that you would be better off utilizing a tin/nickel finish - it will oxidize over time also but you will not need an aggressive flux to remove the oxide and make a metallurgically sound solder joint. Good Luck. Dave Hillman Rockwell Collins [log in to unmask] Jorge A Rodriguez <[log in to unmask]> on 09/14/99 03:22:14 PM Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond to [log in to unmask] To: [log in to unmask] cc: Subject: [TN] Multilayer SMT Voltage Suppressor I am having a hard time soldering a chip component. This 0603 chip is a multilayer surface mount transient voltage surge suppressor from Harris (Part Number V5.5MLA0603H). I am suspecting from the termination finish which it's Silver/Platinum. I already checked the profile and it's OK. I even tried two different solder pastes (no clean and water wash) and I had the same result: dewetting and poor soldering, actually the solder paste seems to reflow without forming a fillet. I taught that maybe the component was contaminated but I discarded that when I learned we had a similar problem with another product using a component with similar termination finish (Silver/Platinum). I am really suspecting that the termination finish is the problem, I would rather have the nickel/tin finish, but according to the vendor they said they've never seen the problem we have with another costumer, it seems we are the only ones. Another thing is that when I made my tests (the two different solder pastes), everything on the board looked OK except those components. Is there anyone who has had problems with Silver/Platinum termination finish?, Is this termination plating more difficult than others?, what are the benefits if we change it to Nickel/Tin? Any advice will be appreciated. Thanks Jorge A. Rodriguez Conexant Systems, Inc. [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. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################