Ok..so what are the causes of solder beads?? > -----Original Message----- > From: Kinol, Vince [SMTP:[log in to unmask]] > Sent: Wednesday, January 19, 2000 6:17 AM > To: [log in to unmask] > Subject: Re: [TN] Reflow soldering >>> Solder balls > > Jens, > I believe the TechNet archives will have some detail on solder balls. In > general there are a few causes for the formation of solder balls. > Environmental exposure of the paste to moisture, this can be from high > humidity, extended queue times after printing or exposure of below room > temperature paste to room temperature air. (ie paste is below dew point) > Another cause would be oxidation of the solder alloy. This may exist in > the > paste or be formed during the reflow process, due to the profile not being > optimized to the flux. > Also just a note solder balls are very small and should not be confused > with > solder beads, large coalesced solder found at times at edges of caps and > resistors. > Feel free to contact me off line for more details. > VBK > Vincent B. Kinol CQE [log in to unmask] <mailto:[log in to unmask]> > Applications Engineer OMG Americas Microbond > Phone 919-544-8090 x298 FAX 919-544-7996 > > > -----Original Message----- > From: [log in to unmask] [SMTP:[log in to unmask]] > Sent: Tuesday, January 18, 2000 11:16 PM > To: [log in to unmask] > Subject: [TN] Reflow soldering >>> Solder balls > > Hi, > > sorry for this basic basic question! > Are there any resources for the solder balls problem? Where do the > come from and how to prevent them? > Is there any site for solder defects info ? > regards > Jens Behrens > > ############################################################## > 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 > ############################################################## ############################################################## 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 ##############################################################