I'll reply to Curt but I meant to reply to all. Let me be specific what I was referring to with regard to my postback to Rob. I used the term, autotheiving, which was/is NOT copper pouring! It refers to "post route" automation tools we used, which placed small copper squares on alternating grid points on all signal layers everywhere there was room to do so, subject to SI constraints on spacing in the X, Y, (and Z axes for non-striplines). There were spaces between the squares, not continuous copper as in a pour. This methodology worked much better than copper pouring (which we tried) and did not perturb signals electrically. The only pain in the neck was the length of time to do all the spacing checks...... Gerry ----Original Message Follows---- From: "Curt McNamara" <CurtM@xxxxxxxxxxx> Reply-To: CurtM@xxxxxxxxxxx To: <rsefton@xxxxxxxxxxxxx>, <si-list@xxxxxxxxxxxxx> Subject: [SI-LIST] Re: Ground Pour in Signal Layers Date: Tue, 28 Feb 2006 14:47:00 -0600 MIME-Version: 1.0 Received: from turing.freelists.org ([206.53.239.180]) by bay0-mc2-f13.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.211); Tue, 28 Feb 2006 13:34:53 -0800 Received: from localhost (localhost [127.0.0.1])by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id A21FA2A6EE9;Tue, 28 Feb 2006 15:49:24 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1])by localhost (turing [127.0.0.1]) (amavisd-new, port 10024)with ESMTP id 29231-09; Tue, 28 Feb 2006 15:49:24 -0500 (EST) Received: from turing (localhost [127.0.0.1])by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 4BC5B2A7350;Tue, 28 Feb 2006 15:49:22 -0500 (EST) Received: with ECARTIS (v1.0.0; list si-list); Tue, 28 Feb 2006 15:47:18 -0500 (EST) Received: from localhost (localhost [127.0.0.1])by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 281682A7C18for <si-list@xxxxxxxxxxxxx>; Tue, 28 Feb 2006 15:47:18 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1])by localhost (turing [127.0.0.1]) (amavisd-new, port 10024)with ESMTP id 29001-03 for <si-list@xxxxxxxxxxxxx>;Tue, 28 Feb 2006 15:47:18 -0500 (EST) Received: from lpdsrv13.logicpd.com (66-162-60-3.gen.twtelecom.net [66.162.60.3])by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 34B432AB449for <si-list@xxxxxxxxxxxxx>; Tue, 28 Feb 2006 15:47:15 -0500 (EST) X-Message-Info: yilqo4+6kc7czcpy3BtsNKyLrjIknBRJNqXAG83xBbc= X-Original-To: si-list@xxxxxxxxxxxxx Delivered-To: si-list@xxxxxxxxxxxxx X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [SI-LIST] Re: Ground Pour in Signal Layers Thread-Index: AcY8l4Soy0udZ7UVQb+24cRm0yb0SQAAPI4AAAO6vQA= X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net X-archive-position: 17849 X-ecartis-version: Ecartis v1.0.0 Errors-To: si-list-bounce@xxxxxxxxxxxxx X-original-sender: CurtM@xxxxxxxxxxx Precedence: normal X-list: si-list X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net Return-Path: si-list-bounce@xxxxxxxxxxxxx X-OriginalArrivalTime: 28 Feb 2006 21:34:57.0780 (UTC) FILETIME=[D25B1B40:01C63CAE] So the signal integrity aspect: Either do it yourself so you know where it is.=20 Or -- Place a requirement on the fab drawing that requires approval of the engineer. This is risky because sometimes the fab vendor will call your layout department and the answer might not be what you would have said! There is another perspective as well: thieving can destroy a clearance and result in losing a safety approval. So it really is best to have your layout team do it. Overall it makes sense -- if you don't have to etch that copper away then process times should decrease, yields should go up and life should be better :-) None of this is huge, but all of our little efforts add up! Curt Curt McNamara. P.E.=20 Senior Electrical Engineer=20 Logic Product Development=20 411 Washington Ave. N Suite 101=20 Minneapolis, MN 55401=20 Tel 612-436-5178=20 Fax 612-672-0443=20 curtm@xxxxxxxxxxx=20 www.logicpd.com=20 This message (including any attachments) contains confidential information intended for a specific individual and purpose, and is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited. -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Robert Sefton Sent: Tuesday, February 28, 2006 1:02 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Ground Pour in Signal Layers Search the TechNet archives. Thieving comes up quite a bit. I'd say the consensus is that thieving on inner layers is important to help bonding. Some also claim it can help reduce warpage. On outer layers it's to achieve more uniform plating. http://listserv.ipc.org/archives/technet.html Bob S. -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Lee Ritchey Sent: Tuesday, February 28, 2006 10:08 AM To: Charles Grasso; Gerry Gagnon; rhaller@xxxxxxxxxxxxx Cc: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Ground Pour in Signal Layers Might want to check with the process engineers at Merix or TTM on this one. > [Original Message] > From: Grasso, Charles <Charles.Grasso@xxxxxxxxxxxx> > To: <leeritchey@xxxxxxxxxxxxx>; Gerry Gagnon <mrgagman@xxxxxxxxxxx>; <rhaller@xxxxxxxxxxxxx> > Cc: <si-list@xxxxxxxxxxxxx> > Date: 2/28/2006 9:34:58 AM > Subject: RE: [SI-LIST] Re: Ground Pour in Signal Layers > > How interesting! I have not had to deal with thieving on inner layers > so I popped down to our layout group and asked our folks there. The=20 > consensus was - YES - Thieving on inner layers can be necessary and=20 > should be used for unbalanced layouts. Indeed one former employee of=20 > DDI indicated that DDI had a program that automatically added thieving > based on the design. The reason for adding the thieving is to avoid=20 > warpage. > > > Best Regards > Charles Grasso > Senior Compliance Engineer > Echostar Communications Corp. > Tel: 303-706-5467 > Fax: 303-799-6222 > Cell: 303-204-2974 > Pager/Short Message: 3032042974@xxxxxxxx > Email: charles.grasso@xxxxxxxxxxxx; > Email Alternate: chasgrasso@xxxxxxxx > ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: =20 //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu =20 ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu