Thanks for the response.
The finish is selective.
Charlie

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Robert Lazzara
Sent: Friday, December 08, 2000 8:48 AM
To: [log in to unmask]
Subject: Re: [TN] GOLD PLATING DEFECT


In a message dated 12/7/00 11:53:52 PM Mid-Atlantic Standard Time,
[log in to unmask] writes:

<< When applying immersion gold onto 4mil wide x 8mil long pads for wire
 bonding, the gold finish result left much to be desired. In a string of
pads
 adjacent to each other, we find a shiny surface of gold next to a very dull
 gold finish. In some cases the color is brown.

 What would cause such an effect in the  same plane? >>

Possibilities:

The "shiny" gold may be a handling effect. Otherwise normal "dull" gold can
become "shiny" if it is rubbed, almost a polishing effect. This may not be
functional to solderability.

The "brown" appearance may suggest gold which is too thin (the underlying
copper is  becoming visible by some degree), or, there was some chemistry
that complexed with the gold finish due to poor rinsing or spillage.

Q: Is the soft gold finish selective, or is the entire PWB finished in soft
gold?

Bob Lazzara
Circuit Connect, Inc.

----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
----------------------------------------------------------------------------
-----

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------