Dave: I believe that the designer would ensure that any vias used as test points would not be tented in the first place. This would have to be defined in the soldermask Gerber layer. John R. Kretsch, P.E. Engineer, Design Assurance ADC Video Systems ______________________________ Reply Separator _________________________________ Subject: Re: FAB: soldermask plugged vias Author: [log in to unmask] at internet-mail Date: 07/23/96 16:25 Dave, You can also have testability issues if you want to hit any vias when you perform your ICT. The test pins will hit the mask and not hit the metal portion of the via. Roger Held Hitachi Computer Products (America), Inc. ______________________________ Reply Separator _________________________________ Subject: FAB: soldermask plugged vias Author: [log in to unmask] at Internet-HICAM-OK Date: 7/23/96 7:52 AM Just curious: We often have customers requesting that the (LPI) soldermask be screened/floodcoated to plug vias with soldermask. I understand the reasons behind the design; however, I'm concerned about potential contaminates being trapped in the via, especially from the HAL or assembly process. This soldermask process can produce vias that are partially to fully plugged from one (or both) sides of the PCB. This can cause inadequate rinsing and cleaning of the vias during the HAL or assembly process. Any other ideas or concerns? Has anyone looked at this issue in detail? (This soldermask process can also produce exposed copper in the via, which has been discussed on this forum. I believe the OSP surface finish would be a much safer choice with this via/soldermask design). Thanks, Dave Boggs Merix Corporation E-mail: [log in to unmask] *************************************************************************** * 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. * *************************************************************************** *************************************************************************** * 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. * ***************************************************************************