Hi Russell- Do you have the option of not having a soldermask on the board? We recently went through an exercise of poor bondability and our simplest solution was the removal of soldermask from the design. We had put soldermask on the board to help prevent "thieving" of solder from the solder pad areas onto the traces. With some extra process control steps we resolved that concern. The exposure of soldermask to the gold bath, curing of the solder mask, etc - all those process steps would/did/could contaminate the bondable gold pads and made wire bonding problematic. One other thing to consider - are you using soldermask as a dielectric ? Ask the question if the soldermask was no longer on the board would you have shorting, arcing, possible dendrite problems between traces because of their exposure either due to the testing (thermal cycling) or use environment? Good Luck. Dave Hillman Rockwell Collins [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: FAB: Wire-bondable gold Author: [log in to unmask] at ccmgw1 Date: 11/13/96 9:17 PM greetings all I am having difficulty with successful production of heavy deposit gold [30-35 micro-inches] of wire-bondable soft gold, since Aurelon shut down their Ni-Au operation. My customer is currently bonding aluminum wire, but desires to go to gold wire. Problems have been: 1. Peeling nickel from copper [resolved] 2. Peeling gold from nickel [mostly resolved] 3. Spotting and discoloration [solved by better rinsing] 4. Texture on gold surface; following the pattern of the tarnish after soldermask and nomenclature oven curing [better after micro-etching before Ni-Au plating] 5. Entrapment of conductive chemistries/metals under the developed edges of Probimer LPI soldermask 6. Marginal peel strength 7. I don't know what is comming next! My process is: Panel plate Tent and etch [cupric chloride] LPI application, now Probimer 52 [but not for long] Nomenclature application, Hy-sol Cat-L-Ink [legend] Immersion/auto-catalytic gold, 30-35 micro-in. [applied by sub-contractor] NC rout Ship [and currently] Receive trash and rejections Can anyone advise me of good combinations of LPI soldermask and Ni-Au chemistries / processes. I don't plate, so I need a contract supplier of Ni-Au plating services, in the So-Cal area? . . . or in No-America as my second choice. Direct responses can be sent to : Russell Ruff at The Circuit Tree [NOT THE MAGAZINE!] 818-303-4648 email [log in to unmask] or to all here at the IPC TechNet forum. Thanks, Russell *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************