Return-Path: <[log in to unmask]> Received: from simon.ipc.org (IPC.ORG [168.113.24.64]) by ixmail4.ix.netcom.com (8.7.5/SMI-4.1/Netcom) id RAA11492; Wed, 16 Oct 1996 17:30:43 -0700 (PDT) Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id TAA06014; Wed, 16 Oct 1996 19:21:30 -0700 Resent-Date: Wed, 16 Oct 1996 19:21:30 -0700 Received: by ipc.org (Smail3.1.28.1 #2) id m0vDeQ3-0000X7C; Wed, 16 Oct 96 17:26 CDT Resent-Sender: [log in to unmask] Old-Return-Path: <[log in to unmask]> Date: Wed, 16 Oct 96 17:53:41 EST From: "joef" <[log in to unmask]> Message-Id: <[log in to unmask]> To: [log in to unmask] Subject: Re[2]: FAB:Wire Bonding Resent-Message-ID: <"upG2q2.0.IlG.C4MPo"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/6937 X-Loop: [log in to unmask] Precedence: list Resent-Sender: [log in to unmask] Besides hardness, our customer has indicated that underlying copper surface topography (i.e., roughness) is a key factor - that, for example, different surface prep methods prior to Ni/Au electroplate (e.g., peroxide-sulfuric u-etch, persulfate u-etch, pumice w/ brushes, pumice w/out brushes, even panel orientation relative to the brushes!!) will affect wire bond yields. Can anyone corroborate this?? And if this theory holds, wouldn't a final pumice of the plated gold surface itself improve things further? Is there a softness threshold below which an abrasive slurry could contaminate the gold?? J.Felts PC World, Toronto ______________________________ Reply Separator _________________________________ Subject: Re: Wire Bonding Author: [log in to unmask] at INET Date: 10/16/96 3:06 PM We also monitor Knoop hardness of the plated deposit from our soft gold bath on a monthly basis. Knoop hardness should be under 80 knoop for gold wire bonding. Kim Hadco Ca. ______________________________ Reply Separator _________________________________ Subject: Wire Bonding Author: [log in to unmask] at SMTPLINK-HADCO Date: 10/15/96 7:08 PM Advice please ! Is there a quantitative test that can be carried out on soft gold electroplate to qualify its suitability for wire bonding ? Gold thickness and purity already to customers spec. Note in this instance gold is on a nickel undercoat. Jim Douglas Kam Circuits *************************************************************************** * 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. * ***************************************************************************