From:	SQS::GSPLASV      "CINDY KEMP ORLANDO ISC 8*826-6873"   27-SEP-1996 
08:31:45.73
To:	SMTP%"[log in to unmask]"
CC:	GSPLASV
Subj:	RE: Black oxide on outer layers

Lou,

We have a CCA supplier that requested this on one of our programs to reduce the 
amount of touch-up on dry film solder mask over large ground plane areas; they 
were getting small areas of exposed copper after wave solder on very large, 
thick boards (12" X 27", 0.105" thick).  The boards saw a lot of heat in the 
process to get good top side wetting with RMA flux.  This did create better 
adhesion of the DRYFILM soldermask through the assembly process.  I would be a 
bit leary though of the board supplier asking for this.  You did not say what 
kind of soldermask you are using - we have not had this problem at all with LPI 
types of soldermask on newer designs.  The board manufacturer should not be 
having the problem, but rather the assembler.

Cindy Kemp
Lockheed Martin
Orlando, FL
(407) 306-6873
email:  [log in to unmask]

*******************************************************************************  

Greetings !

The Fab house that we use has recently asked us if they could use a black 
oxide treatment on external layers of our designs. I know that this process 
is used for internal layers but I want to know if any of you have used it 
for external layers ? Their reason for using it is " To create better 
adhesion for the solder mask and eliminate potential slivers ". To me, this 
sounds more like a process problem. What do you think ?

To recap, do any of you use a black oxide coating on outer layers ?   If so,
 why ?.   If not, why not ?

Thanks in advance for your help !

Lou Takach

Union Switch & Signal Inc.
412.688.2574 (voice)
412.688.2399 (fax)
[log in to unmask]

***************************************************************************
* 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.        *
***************************************************************************