Hi George! We call out the specific immersion silver chemistry mostly due
to our overall fright of the world and complete distrust of all technical
data that is not our own! Just kidding - the main reason for calling out a
specific immersion silver chemistry is our customer base comfort zone -
over time we plan to migrate to calling out just immersion silver and have
a qualified list of specific chemistries. As we complete more specific
immersion silver chemistry qualifications and find no problems then the
practice of calling out a specific chemistry is nonvalue added. We follow
the same practice with the immersion tin finishes and have found that "not
all immersion tin finishes are created equal"! Our current internal
qualification requirements for an immersion finish is that it pass
solderability (JSTD-003A) after 4 thermal excursions.
Dave
"Wenger, George
M." To: "TechNet E-Mail Forum." <[log in to unmask]>, <[log in to unmask]>
<George.Wenger@an cc:
drew.com> Subject: RE: [TN] inmmersion silver
10/23/2003 08:30
AM
Dave,
Why call out the specific immersion silver chemistry? Have you found
problems with various suppliers chemisty? Our fabricators have used
immersion silver chemistry from at least two major suppiers and we haven't
seen problems with either. Our internal specification used to be 2 to 10
microinches and we changed it about 3.5 years ago to be 2 to 20 microinches
because the chemistry from one of the two suppliers plates typically plates
twice as thick as the other. Our preference for thickness is 2 to 4
microinches but fabricators have a hard time plating 0.000003" +/-
0.000001" so we set the wide range of 2 to 20 microinches and haven't seen
any problems. In fact there have been several cases in the past 5 or 6
years that we've gotten boards outside the 2 to 20 range (boards with 0.5
to 1.5 microinches and boards with 23 to 28 microinches) and used them
without any problem.
Regards,
George
George M. Wenger (908)-546-4531
Reliability Engineer
RF Power Amplifier Group
Andrew Corporation, 40 Technology Drive, Warren, NJ 07059
[log in to unmask]
-----Original Message-----
From: Dave Hillman [mailto:[log in to unmask]]
Sent: Thursday, October 23, 2003 9:17 AM
To: [log in to unmask]
Subject: Re: [TN] inmmersion silver
Hi Jim! The 4-14 Plating Processes subcommittee is currently working on
specifications for immersion silver and immersion tin. ENIG was covered
with the publication of the IPC-4552 specification. I would recommend you
call out the specific immersion silver chemistry, a thickness range and a
solderability requirement on your drawing note(s) until the 4-14 committee
can complete their work. Good Luck.
Dave
"Marsico, James"
<James.Marsico@DP To: [log in to unmask]
.AIL.COM> cc:
Sent by: TechNet Subject: [TN] inmmersion
silver
<[log in to unmask]>
10/23/2003 06:30
AM
Please respond to
"TechNet E-Mail
Forum."; Please
respond to
"Marsico, James"
Hello Technet:
What's the best way to specify immersion silver finish on a PWB? In
accordance with what? Thickness? Anything else?
Jim Marsico
Senior Engineer
Production Engineering
EDO Electronics Systems Group
[log in to unmask] <mailto:[log in to unmask]>
631-595-5879
---------------------------------------------------
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
847-509-9700 ext.5315
-----------------------------------------------------
---------------------------------------------------
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
847-509-9700 ext.5315
-----------------------------------------------------
------------------------------------------------------------------------------------------------
This message is for the designated recipient only and may
contain privileged, proprietary, or otherwise private information.
If you have received it in error, please notify the sender
immediately and delete the original. Any unauthorized use of
this email is prohibited.
------------------------------------------------------------------------------------------------
[mf2]
---------------------------------------------------
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 847-509-9700 ext.5315
-----------------------------------------------------
|
