TECHNET Archives

October 1998

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:
Russ Steiner <[log in to unmask]>
Reply To:
Date:
Fri, 23 Oct 1998 07:54:44 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (64 lines)
Chan - I had great success working with Circuits DMA in the past.  They're
in
Livonia Michigan.  They have been plugging vias reliabally for years.  They
too had tried
the dry film LPI combo - to no avail. The dry film seals a the ends of the
barrels
and produces a small gas chamber that can blow up later during assembly.
Then, it tends
to entrap flux and cleaners in the barrel.  Later you get caustic and other
reactions
caused by that entrapment.  Try CDMA - they plug the holes instead of
tenting.
I worked with Lance Field at 734 525-0600.  Regards, Russ Steiner
[log in to unmask]

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Chan, Marcelo
Sent: Thursday, October 22, 1998 2:33 PM
To: [log in to unmask]
Subject: [TN] Plugged/tented vias


We have tried different approaches to tenting/plugging vias for BGA and some
backplane applications using LPI and screened SM with limited success...PWB
vendors claim they could do it, but we are still looking for some one who
could
do this on 100% of the vias with no pin holes and it has to be done on both
sides to prevent entrapment of cleaning solutions...the via sizes that we
have
in mind can have a finished hole diameter as large as 22 and as small as 13
mils...Can someone share their 'hands-on' experiences on this issue with me
through Technet or even off-line?
Thanks

Marcelo Chan
Lead Engineer - Advanced Manufacturing Technology
Electronics Systems Sector, Harris Corp., FL

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section
for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or
847-509-9700 ext.312
################################################################

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet 
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################


ATOM RSS1 RSS2