are you guys sure it is connector? not leadframe?
                              jk

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Jeffrey Bush
Sent: Thursday, January 13, 2005 7:59 AM
To: [log in to unmask]
Subject: Re: [TN] FAB - Al Wire Bonding


Connector fingers should be plated with harder gold - Knoop over 130.
Bondable gold is either AL or AU/Ball bonding.  In AL wire bonding the
bond is to the under plate of NI.  Some are successful at bonding the
electroless NI, but most are not.  Electrolytic NI seems to offer the
best reliability.  In this case I would call for a thin coating of soft
AU (17 uinches max), as the bonding action scrubs the protective AU
coating away to reach the NI layer.  Thicker gold will create bonding
issues for AL wire bond.  Using the thinner gold may also allow you to
go full body gold (for soldering also) and depending on the geometry of
the circuit is could be more economical that using selective gold
plating.  The electrolytic NI plating should be 118 uinches min.


Jeffrey Bush
Director, Quality Assurance and Technical Support

VERMONT CIRCUITS INCORPORATED
  76 Technology Drive - POB 1890
    Brattleboro, Vermont 05302
      Voice: 802.257.4571.21 Fax: 802.257.0011
           http://www.vtcircuits.com


-----Original Message-----
From: John Parsons [mailto:[log in to unmask]]
Sent: Wednesday, January 12, 2005 6:32 PM
To: [log in to unmask]
Subject: [TN] FAB - Al Wire Bonding

Greetings all,
I am trying to learn something about the wire bonding process.  Our
customer
has a part on which they spec the finish of some edge connector fingers
as
"Gold Plated for Wire Bonding Al Wire".  As we do not provide a wire
bondable gold finish in-house we have subcontracted the service.  The
plating service tells me that typically for Al wire bonding all that is
required is a typical ENIG process (5-10u" Au over 200u" Ni).  I believe
that in past verbal communications with the customer they have said that
an
ENIG finish would not suffice and that they require 15u" of bondable
gold
(electroless gold or electroplated??) .

What say you? Or does "it depend" :-)

Regards
John Parsons

---------------------------------------------------
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
-----------------------------------------------------