No underfill or any other fancy stuff ---- On Wed, 09 Dec 2015 16:53:28 -0800 Yuan-chia Joyce Koo<[log in to unmask]> wrote ---- > tin oxalyate used for epoxy catalyst... there were works for flux/ > underfill one step stuff utilize flux by product as catalyst for > curing... (can't remember which group did that...) > jk > On Dec 9, 2015, at 7:03 PM, Vladimir Igoshev wrote: > > > Hi Dave, > > > > Not really. It doesn't "burn" or "curl" much under the beam, so > > it's solid. > > > > Vladimir > > > > ---- On Wed, 09 Dec 2015 15:51:29 -0800 David > > Hillman<[log in to unmask]> wrote ---- > >> Thank you Steve! > >> > >> Vlad - does the substance slightly charge in the SEM? > >> > >> Dave > >> > >> On Wed, Dec 9, 2015 at 5:46 PM, Steve Gregory <[log in to unmask]> > >> wrote: > >> > >>> Hi Dave and Vlad, > >>> > >>> I have it up here: > >>> > >>> http://stevezeva.homestead.com/What_else_it_can_be.pdf > >>> > >>> Steve > >>> > >>> On Wed, Dec 9, 2015 at 4:34 PM, David Hillman < > >>> [log in to unmask]> wrote: > >>> > >>>> HI Vlad - we can't open Dropbox here due to firewall > >>>> restrictions so can > >>>> you have Steve G. post the pictures? > >>>> > >>>> Dave Hillman > >>>> Rockwell Collins > >>>> [log in to unmask] > >>>> > >>>> On Wed, Dec 9, 2015 at 4:59 PM, Vladimir Igoshev < > >>>> [log in to unmask] > >>>>> wrote: > >>>> > >>>>> HI everyone, > >>>>> > >>>>> I'm attaching a link to a file showing something I'd appreciate > >>>>> your > >>>>> thoughts on. It's a cross-section of a QFN on an IAg board; > >>>>> Pb-free/no-clean process. As you can see from the EDS spectrum, > >>>>> that > >>>>> greyish stuff between pins has pretty much only Sn and O in its > >>>> elemental > >>>>> composition. > >>>>> > >>>>> I know there is burn flux residue around solder joints but that > >>>>> stuff > >>>>> doesn't have any C in it. The question I have is what is it. > >>>>> > >>>>> I spoke to Bev and both of us are still puzzled. > >>>>> > >>>>> Here is the link: > >>>>> > >>>> https://www.dropbox.com/s/3wbj62vqjyhvj2y/What%20else%20it%20can% > >>>> 20be.pdf?dl=0 > >>>>> > >>>>> Thank you very much in advance. > >>>>> > >>>>> Regards, > >>>>> > >>>>> Vladimir > >>>>> > >>>>> SENTEC > >>>>> > >>>>> > >>>>> __________________________________________________________________ > >>>>> ____ > >>>>> This email has been scanned by the Symantec Email Security.cloud > >>>> service. > >>>>> For more information please contact helpdesk at x2960 or > >>>> [log in to unmask] > >>>>> __________________________________________________________________ > >>>>> ____ > >>>>> > >>>> > >>>> > >>>> ___________________________________________________________________ > >>>> ___ > >>>> This email has been scanned by the Symantec Email Security.cloud > >>>> service. > >>>> For more information please contact helpdesk at x2960 or > >>>> [log in to unmask] > >>>> ___________________________________________________________________ > >>>> ___ > >>>> > >>> > >>> > >>> > >>> This email and any attachments are only for use by the intended > >>> recipient(s) and may contain legally privileged, confidential, > >>> proprietary > >>> or otherwise private information. Any unauthorized use, > >>> reproduction, > >>> dissemination, distribution or other disclosure of the contents > >>> of this > >>> e-mail or its attachments is strictly prohibited. If you have > >>> received this > >>> email in error, please notify the sender immediately and delete the > >>> original. > >>> > >> > >> > >> _____________________________________________________________________ > >> _ > >> This email has been scanned by the Symantec Email Security.cloud > >> service. > >> For more information please contact helpdesk at x2960 or > >> [log in to unmask] > >> _____________________________________________________________________ > >> _ > >> > > > > > > > > ______________________________________________________________________ > > This email has been scanned by the Symantec Email Security.cloud > > service. > > For more information please contact helpdesk at x2960 or > > [log in to unmask] > > ______________________________________________________________________ > > > ______________________________________________________________________ > This email has been scanned by the Symantec Email Security.cloud service. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________