Reply to: RE>ENTEK 106 Peter: Although I did not respond to the initial e-mail, I do have some caveats for Entek users to share with the "Net", based on personal experience: 1) If the PCBs are left in the microetch too long prior to ENTEK application, the underlying copper (especially in the vias) is dissolved and can cause intermittent operation or "hard" opens when the assembly heats up. Recommendation: 100% electrical test AFTER ENTEK application. 2) Along the same lines, "strip and reapplication" of ENTEK should NOT use a predip microetch, unless the boards are 100% retested after the reapplication. If the original copper is thin, additional microetching could create open vias that will go undetected during final visual inspection. Recommendation: Try stripping ENTEK with IPA followed by DI rinse, rather than microetch. If this does NOT correct the condition, refer to item 1 above. 3) The drying step is very important! If the boards do not go through a post-ENTEK bake and are placed in plastic bags, the moisture left in the vias will seep into the bag during shipping and cause "water spots" or thin areas of ENTEK that could promote localized oxidation, which is detrimental to good solderability. Recommendation: Have bare boards baked by PCB vendor prior to final packaging for shipment. IMO, ENTEK-106 is STILL the best choice for fine-pitch SMT designs, in spite of these "caveats". Bill Fabry Process/QA Mgr Truevision, Inc [log in to unmask] -------------------------------------- Date: 11/4/96 10:03 AM To: Bill Fabry From: peterb Jeffery Harry, would you please expand on the "major problems" you have seen by running Entek 106 in a dip mode. Peter Blokhuis PC World [log in to unmask] ---------------------------------------------------------------------- If you use Entec 106, make sure that the PCB supplier has an in-line process. Dip tanks will cause major problems. Also the PCBS need to be thoroughly dried before packaging. If not, you will have solderability problems. Jeffrey_Harry @ 3mail.3com.com@ ugate ----- Previous Message ---------------------------------------------------- To: Technet @ ipc.org @ UGATE cc: From: EHolton @ vines.etn.com @ UGATE Date: Thursday October 31, 1996 02:40 PM Subject: OSP Coating ---------------------------------------------------------------------- ---------- ---------------------------------------------------------------------- ---------- ------------------------------ Fellow technetters: My company is beginning its research into the wonderful world of organic solderability preservative coatings. Our goal being to implement this on the circuit boards in the near future. I am looking for any and all information that anyone may have.... *************************************************************************** * 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. * *************************************************************************** ------------------ RFC822 Header Follows ------------------ Received: by rainbow.truevision.com with SMTP;4 Nov 1996 09:57:01 U Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id LAA27805; Mon, 4 Nov 1996 11:39:41 -0800 Resent-Date: Mon, 4 Nov 1996 11:39:41 -0800 Received: by ipc.org (Smail3.1.28.1 #2) id m0vKSCu-0000UWC; Mon, 4 Nov 96 10:49 CST Resent-Sender: [log in to unmask] Old-Return-Path: <[log in to unmask]> Date: Mon, 04 Nov 96 10:49:55 EST From: "peterb" <[log in to unmask]> Message-Id: <[log in to unmask]> To: [log in to unmask] Subject: Entec 106 Resent-Message-ID: <"6gpbM2.0.H-O.svXVo"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/7365 X-Loop: [log in to unmask] Precedence: list Resent-Sender: [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. * ***************************************************************************