The more the flux is 'cooked', the harder it is to remove. As you apparently use a rosin-based flux, it may become very difficult. It is not helpful to say you use an ultrasonic cleaner without telling us your soldering time/temp profile, cleaning products and procedure, ultrasound data etc. I suggest you consult your flux manufacturer for advice on how HIS flux residues may be best removed. For cleaning to wire-bonding standards, you will probably have to go to more than a solvent, such as Vigon or Kyzen products, if the flux maker cannot help. There is no 'best' product. Brian jonathan noquil wrote: > Hi All > What is the best flux cleaning agent that can effectively remove flux on > ENiAu bond pads? > We solder a copper strap on the silicon with PbSn5 at 350 degc temperature, > the flux contaminates the bonding pads. > Paste is from Heraues. We used an ultrasonic cleaning equipment. > During Au wirebonding, we have lots of bond off occurences? We tried to do > FTIR on the surface and found some traces of that resin contamination. > > Is the flux difficult to remove with flux cleaning agent when it was > reflowed at high temperature? > > > Thanks > > > ______________________________________________________________________ > This email has been scanned by the MessageLabs Email Security System. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 > ----------------------------------------------------- > ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------