I agree strongly with Guy's approach below on this or any other process opinion solicitation. I can guarantee you can find people who have had very positive and very negative experiences with ANY process used to make PWBs. The approach I always council is that the process has to be right for YOUR SHOP. So the first thing you need to do is qualify and quantify you situational needs. If you can get an excellent handle on what you will require from a process, then it becomes easier to chose which process is right for you. Also, when someone gives you a good recommendation about a process, find out what their situational needs were when they bought into that particular process. When someone has had a bad experience, find out their situation as well if you can. It may very well not apply to YOUR situation. The suppliers of processes or equipment should be willing to present proof sources for you to quiz. Take your time talking to these people and find out what they really do with the process or equipment and what they expect from the process or equipment. Well, that's enough. My soapbox is getting rickety. Dave Sullivan Rockwell Collins, Inc. [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: Re: FAB: Horizontal versus vertical etching Author: [log in to unmask] at ccmgw1 Date: 1/29/97 5:27 PM This is a very big question. You will receive a lot of pro's and con's for each process. (I know I have my opinions) The best thing you can do is decide what you are looking for in a finished etched trace geometry. Process samples of different line widths and take many cross sections. When you take your cross sections you will want to cross section both top and bottom (horizontal) / left or right (vertical) of the substrate as it was processed as well as traces that are processed in parallel and perpendicular and at 45 degree angle to the direction of travel of the substrate as it was processed. When you read these cross sections you will be focused on what the sidewall characteristic is of the left and right side of each trace and how they relate to each other based on direction and position. With the se cross sections you must also look at the position on the conveyor top center bottom on vertical or left center right of a horizont al unit. Once you gather this data you can then determine which pr ocess will meet YOUR expectations. Include in this decision controlled impedance and very fine lines if this is part of your goal. When you measure the line widths make sure you compare the measurement to the exact location on the A/W that was used to image the test panel. Line widths on A/W vary and you want to remove this variation from your comparison. Because each shop's expectations are different each process finds it's own niche. Guy Willingham Zycon [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: FAB: Horizontal versus vertical etching Author: [log in to unmask] at corp Date: 1/29/97 3:16 AM We would like to receive input on the positive and negative aspects of horizontal etching with oscillating spray bars, versus vertical etching of inner layers and outer layers using an alkaline etchant. We would like to hear of experiences as to which method provides the best results in terms of line width uniformity, top to bottom consistency, and conveying of cores as thin as .004 with half ounce copper on both sides. Panel sizes vary from 12 X 12 to 21 X 30. Line and spaces down to .004 X .004 for the smaller panels, .008 X .008 on the larger panels. Please presume that equipment of either type is well maintained and that the chemistry is under good control. Many thanks, Luis Rivera CompuRoute, Inc. Dallas, TX [log in to unmask] (214) 340-0543 *************************************************************************** * 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. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [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. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * *************************************************************************** Received: from by ccmgw1.cacd.rockwell.com (SMTPLINK V2.11) ; Wed, 29 Jan 97 17:27:09 cst Return-Path: <[log in to unmask]> Received: from stealth.cacd.rockwell.com (stealth) by mailserv with ESMTP (1.40.112.8/16.2) id AA143050430; Wed, 29 Jan 1997 17:27:10 -0600 Received: by stealth.cacd.rockwell.com; id RAA15977; Wed, 29 Jan 1997 17:26:34 -0600 Received: from unknown(168.113.24.64) by stealth via smap (V3.1.1) id xma015975; Wed, 29 Jan 97 17:26:16 -0600 Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id RAA11932; Wed, 29 Jan 1997 17:16:19 -0800 Resent-Date: Wed, 29 Jan 1997 17:16:19 -0800 Received: by ipc.org (Smail3.1.28.1 #2) id m0vpfNh-0000ilC; Wed, 29 Jan 97 13:09 CST Resent-Sender: [log in to unmask] Old-Return-Path: <[log in to unmask]> Date: Wed, 29 Jan 97 09:20:45 PST From: "gwilling" <[log in to unmask]> Message-Id: <[log in to unmask]> To: [log in to unmask] Cc: [log in to unmask], [log in to unmask] Subject: Re: FAB: Horizontal versus vertical etching Resent-Message-Id: <"QbjCP1.0.IZB.M1wxo"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/9749 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. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************