First, as of Silver - my spec is for Sterling, complying to the thick coating specified in IPC-4553
Second - we selected the ImAg by elimination of the other options, because:
1. Gold - black pads and non-compliance to press fit (the Ni is broken)
2. OSP - I let others to prove reliability under LF soldering conditions,
3. ImSn - whiskers, so I limit this finish to back planes, where the press fit connectors are dominant.
I know about the contradicting opinions about the probability of the black pads, but when placing 5 to 7 1400 pins BGA on every card (and these monsters are costing their weight in gold). Also I assume that after specifying a chemistry that is relatively immune to whiskers, the probability of getting these in my products is low. Yet, I prefer to be the wise as in the old saying : A smart guy is that person who will get out of a trouble that a wise guy wouldn't get into.
Regards
Ofer Cohen
Manager
Quality Assurance, Reliability and Production Technologies
Seabridge Ltd. - A Siemens Company
-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of John Burke
Sent: Tuesday, April 26, 2005 23:13
To: [log in to unmask]
Subject: Re: [TN] gold vs copper plating on pcb's
Victor, I know exactly what you are referring to, but would ask that you
point to some published data that backs up that statement.
Kind regards,
John Burke
-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Victor G. Hernandez
Sent: Tuesday, April 26, 2005 2:04 PM
To: [log in to unmask]
Subject: Re: [TN] gold vs copper plating on pcb's
Bob, Lee,
Beware of the immersion silver plating layer thickness which may
cause micro voiding at the PWB side of the interface with LF.
Victor,
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Lee parker
Sent: Tuesday, April 26, 2005 3:56 PM
To: [log in to unmask]
Subject: Re: [TN] gold vs copper plating on pcb's
Bob
Several large OEMs are using immersion silver and others OSPs. You may
want to get some samples of immersion silver made as well.
Best regards
Lee
J. Lee Parker, Ph.D.
JLP Consultants LLC
804 779 3389
----- Original Message -----
From: Bob Arciolla<mailto:[log in to unmask]>
To: [log in to unmask]<mailto:[log in to unmask]>
Sent: Tuesday, April 26, 2005 4:41 PM
Subject: [TN] gold vs copper plating on pcb's
Good Afternoon all,
Our company will be switching over to lead free and we have received
sample pcb's from one of our vendors and one board has gold (ENIG) for
the traces and one has copper (OSP). From some of the emails I have seen
on Technet it appears that gold is what most of companies are going to
be using? Is this correct or is there some other materials we should be
looking into to use? Is the gold more reliable than the copper?
Any input would be greatly appreciated.
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to
[log in to unmask]<mailto:[log in to unmask]> with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]<mailto:[log in to unmask]>: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]<mailto:[log in to unmask]>: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/cont
entpage.asp?Pageid=4.3.16> for additional information, or contact Keach
Sasamori at [log in to unmask]<mailto:[log in to unmask]> or 847-615-7100
ext.2815
-----------------------------------------------------
Regards, Bob
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text
in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
