Mel,
I was thinking more of the popular commercial conductive adhesives available
today. All of the studies I have seen recently say that these have improved,
but still lag behind solders as far as conductivity, reliability, and
reworkabilty.
Honestly, though, I do not have a great deal of first hand experience with
these, and I would appreciate some insight from those with a bit more
expertise than me.
Thanks,
David
-----Original Message-----
From: Mel Parrish <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Wednesday, July 07, 1999 9:22 AM
Subject: Re: [LF] Component reliability at higher soldering temperatures
David
Can you enlighten us to the types of conductive polymer considered. In my
experience, the material selection provides significant definition for
performance ands stability not even considering the stuff that China Lake
and some others were working with that they consider "true polymers"
Mel Parrish
ACI/EMPF
One international Plaza, Suite 600
Philadelphia, PA 19113
[log in to unmask]
www.empf.org
610 362 1200 x238/610 362 1295
610 362 1289 Fax
-----Original Message-----
From: David D Hillman [SMTP:[log in to unmask]]
Sent: Wednesday, July 07, 1999 8:52 AM
To: [log in to unmask]
Subject: Re: [LF] Component reliability at higher soldering
temperatures
Hi folks! One major issue with the use of conductive polymers as solder
replacements has been the problem of long term electrical signal stability.
Some electronics applications are quite sensitive to either resistive or
inductive electrical signal changes and many conductive polymers don't work
well in those situations (ok, keep the flames down to a low roar!). Now I
also need to give the conductive polymer folks some credit - the latest
generation of conductive material science has made great strides in
performance. It may be that the electronics design/assembly community needs
to look at conductive polymers as one part of an overall leadfree solder
solution. Some of the testing I have participated in did show that
conductive polymers performed well in some applications and use
environments.
Dave Hillman
Rockwell Collins
[log in to unmask]
David Suraski - AIM <[log in to unmask]> on 07/07/99 07:32:54 AM
Please respond to "Leadfree Electronics Assembly E-Mail Forum."
<[log in to unmask]>; Please respond to David Suraski - AIM
<[log in to unmask]>
To: [log in to unmask]
cc:
Subject: Re: [LF] Component reliability at higher soldering temperatures
Peter Brooks writes: "Maybe this is the time to consider the elimination of
the solder assembly
process?"
I have heard this sentiment before. Does anyone see this as feasible? I
always have been under the impression that it is not, considering the lack
of electrical conductivity, rework-ability, and strength of conductive
adhesives.
Is there a general consensus on this issue?
-----Original Message-----
From: Brooks, Peter <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Wednesday, July 07, 1999 8:29 AM
Subject: Re: [LF] Component reliability at higher soldering temperatures
>David:
>
>Obviously there is a point (more like a cliff edge) where any component
will
>fail. I have internally asked our reliability department to come up with
an
>assembly "not to exceed" profile (maximum ramp/cooling rate and maximum
>time/temperature etc) that could be used as boundary conditions for this
>project.
>
>The comment that came back was that this is "IMPOSSIBLE" considering all
the
>different packages/materials used for IC's and Discretes.
>
>Maybe this is the time to consider the elimination of the solder assembly
>process?
>
>Peter Brooks
>
> -----Original Message-----
> From: David Suraski - AIM [SMTP:[log in to unmask]]
> Sent: Wednesday, July 07, 1999 7:36 AM
> To: [log in to unmask]
> Subject: Re: [LF] Component reliability at higher soldering
>temperatures
>
> Are there any component manufacturers involved in this forum who
could
> comment on the issue below (and others)?
>
> Thanks,
>
> David
>
> -----Original Message-----
> From: Charbonneau, Richard A <[log in to unmask]>
> To: 'David Suraski - AIM' <[log in to unmask]>
> Cc: 'Seelig, Karl (AIM solder)' <[log in to unmask]>
> Date: Tuesday, July 06, 1999 6:55 PM
> Subject: Component reliability at higher soldering temperatures
>
>
> >re: recent posting to IPC Lead-free forum
> >
> ><edited>
> >
> >we have found that most components can withstand this extra heat
w/no
> >degradation to their reliability....
> >
> >David, I would like to respond to your comment.
> >
> >The feedback that we are receiving from our supplier base is that
the
> higher
> >soldering temperatures (even the lower 240 peak profile)is a
>reliability
> >concern for a wide range of purchased parts including film
capacitors,
> >switchs, relays, connectors, crystals, hybrids and optoelectronic
>devices
> to
> >name a few.
> >
> >regards,
> >
> >richard charbonneau
> >
> >
> >
>
> ################################################################
> Leadfree 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 Leadfree <your full name>
> To unsubscribe: SIGNOFF Leadfree
> ################################################################
> IPCWorks -October 25-28 featuring an International Summit on
Lead-Free
>Electronic
> Assemblies.
> Please visit IPC's Center for Lead-Free Electronics Assembly
> (http://www.ipc.org/html/leadfree.htm ) for additional
information.
> For technical support contact Gayatri Sardeshpande [log in to unmask]
or
>847-790-5365.
> ################################################################
>
>################################################################
>Leadfree 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 Leadfree <your full name>
>To unsubscribe: SIGNOFF Leadfree
>################################################################
>IPCWorks -October 25-28 featuring an International Summit on Lead-Free
Electronic
>Assemblies.
>Please visit IPC's Center for Lead-Free Electronics Assembly
>(http://www.ipc.org/html/leadfree.htm ) for additional information.
>For technical support contact Gayatri Sardeshpande [log in to unmask] or
847-790-5365.
>################################################################
>
################################################################
Leadfree 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 Leadfree <your full name>
To unsubscribe: SIGNOFF Leadfree
################################################################
IPCWorks -October 25-28 featuring an International Summit on Lead-Free
Electronic
Assemblies.
Please visit IPC's Center for Lead-Free Electronics Assembly
(http://www.ipc.org/html/leadfree.htm ) for additional information.
For technical support contact Gayatri Sardeshpande [log in to unmask] or
847-790-5365.
################################################################
################################################################
Leadfree 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 Leadfree <your full name>
To unsubscribe: SIGNOFF Leadfree
################################################################
IPCWorks -October 25-28 featuring an International Summit on Lead-Free
Electronic
Assemblies.
Please visit IPC's Center for Lead-Free Electronics Assembly
(http://www.ipc.org/html/leadfree.htm ) for additional information.
For technical support contact Gayatri Sardeshpande [log in to unmask] or
847-790-5365.
################################################################
################################################################
Leadfree 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 Leadfree <your full name>
To unsubscribe: SIGNOFF Leadfree
################################################################
IPCWorks -October 25-28 featuring an International Summit on Lead-Free
Electronic
Assemblies.
Please visit IPC's Center for Lead-Free Electronics Assembly
(http://www.ipc.org/html/leadfree.htm ) for additional information.
For technical support contact Gayatri Sardeshpande [log in to unmask] or
847-790-5365.
################################################################
################################################################
Leadfree 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 Leadfree <your full name>
To unsubscribe: SIGNOFF Leadfree
################################################################
IPCWorks -October 25-28 featuring an International Summit on Lead-Free Electronic
Assemblies.
Please visit IPC's Center for Lead-Free Electronics Assembly
(http://www.ipc.org/html/leadfree.htm ) for additional information.
For technical support contact Gayatri Sardeshpande [log in to unmask] or 847-790-5365.
################################################################
|
