TECHNET Archives

August 2005

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Eric CHRISTISON <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Eric CHRISTISON <[log in to unmask]>
Date:
Wed, 17 Aug 2005 09:33:07 +0100
Content-Type:
text/plain
Parts/Attachments:
text/plain (58 lines)
If the silicon, and consequently the bond wires, are encapsulated in epoxy overmoulding it's very unlikely that you will have a problem.

If the bond wires are in air then I'd still be surprised if you had failures. Our standard package for our product has been a CLCC package with non encapsulated silicon i.e. the bond wires are unconstrained. The normal PCB cleaning method in our workshop is a 15 minute US clean and I've never heard of this causing a failure.

My only health warning for the above is that our devices are always destined for consumer products, they don't go into space or any other challenging environments.

Regards,

 

Eric  Christison
Mechanical Engineer
Home, Personal, Communication Sector - Imaging Division
STMicroelectronics
33 Pinkhill
Edinburgh
EH12 7BF

Tel:     +44 (0)131 336 6165
Fax:    +44 (0)131 336 6001



> 
> David Tremmel wrote:
> > Dear forum,
> >
> > I have some microBGAs which have a no-clean flux residue which must be
> > removed before they can be reballed.
> >
> > I have been doing my homework regarding USC (ultrasonic cleaning) and
> > would like opinions on whether or not putting the microBGAs in alcohol
> > and putting them through a US cleaning cycle for 1 minute would damage
> > the wirebonding.
> >
> > Most of what I see regarding USC is negative, but would only a minute
> > be damaging to the parts or does the damage occur after more time
> > (i.e. - 3 minutes, 5 minutes).
> >
> > As always, I appreciate the feedback.
> >
> >
> > David
> >
> > P.S. - Ramon, you said a 15 minute soak in alcohol would do trick, right?
> >
> >

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

ATOM RSS1 RSS2