How thick was the Gold on these boards? We have some boards with soldering problems in house which on surface pads have 10-15 micro-inches of gold.There was also seen balls microscopic balls of gold lining the top of PTHs. -----Original Message----- From: d. terstegge [mailto:[log in to unmask]] Sent: Wednesday, June 21, 2000 4:41 AM To: [log in to unmask] Subject: Re: [TN] Ag on Ni - effect of baking Hi Richard, I recently had some solderability problems with Ni/Au boards, where the boardsuppliers told us we had the problems because of baking or because of a few days storage time between subsequent soldering steps. But never could they show me any supporting evidence for baking being such a bad thing for this type of board. From some helpfull Technetters (people who I consider much more knowledgable than the average fabs-salesman dealing with a complaint) I learned that if a Ni/Au board solders badly because of baking, there is definitely a problem with the board. Kind Regards, Daan Terstegge SMT Centre Signaal Communications Unclassified mail Personal Website: http://surf.to/smtinfo >>> Richard Tilbrook <[log in to unmask]> 06/21 9:29 am >>> NEW MESSAGE: Hi folks, Sorry, I wasn't feeling well yesterday and did not explan myself at all - the reason I asked about baking is that we reflowed one side of a surface mount board (gold on nickel); we then stored it in a 45'C oven as we were expecting the remaining parts to arrive for this very urgent job. They unexpectedly took a week. They even more unexpectedly didn't want to reflow properly when we tried reflowing. I suggested "passivation" as something for the person who brought me the problem to think about, though I must confess that being an industrial placement student, I am not best equiped to make that kind of judgement. As I try to follow many of your TN discussions, and occasionally add when I feel able, I was sure you'd be able to give better reasons as to the cause and suggestions for either prevention or cure. Thanks and Regards, Richard Tilbrook PREVIOUS MESSAGE: Hi technetters, I'm hoping to find out a bit more about the effect of baking (at 45 deg. C) on boards with gold on nickel. I would be grateful for any info on the sibject, including times, temperatures and effects, such as passivation. Thanks, Richard TIlbrook ############################################################## 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 Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ############################################################## ############################################################## 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 Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ############################################################## ############################################################## 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 Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################