Electronics Forum | Sat Jan 23 17:00:44 EST 1999 | Earl Moon
| | Hi Everyone, | | We plan to build, for reliability/experimental/research purpose some CSPs (namely Tessera microBGA 46-I/O 0/75mm pitch and TI 64 I/O 0/8 mm pitch). the various factors that we plan to evaluate are the reliability and assembly con
Electronics Forum | Thu Mar 05 07:49:00 EST 1998 | Steve Gregory
Hi Ron, Your question really opens up a "Pandora's box", but when you say you're not able to print perfectly, what is it exactly that you mean? Is the print lacking volume? Is it mis-registered? Are you bridging? Also, what printers have you used? Do
Electronics Forum | Thu Aug 12 20:31:57 EDT 1999 | Kelly Morris
| | Hello | | | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | | 100 durometer blade. Getting "tails" o
Electronics Forum | Thu Aug 12 20:48:05 EDT 1999 | JAX
| | | Hello | | | | | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | | | 100 durometer blade. Getting "
Electronics Forum | Thu Aug 12 21:08:39 EDT 1999 | ScottM
| | | | Hello | | | | | | | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | | | | 100 durometer blade. G
Electronics Forum | Wed Jul 21 11:49:24 EDT 1999 | Deon Nungaray
| | | | I recently switched from solder paste in 500 gram jars to 500 gram tubes. I did this to try to limit the time the paste is exposed to the room environment. But we have a need to clean the stencil every 4 - 5 boards which means taking the bulk
Electronics Forum | Sat Feb 20 23:08:36 EST 1999 | GORDON DURPHEY
| Hey all- | | My question is this: My stencil printer operator has said that he has to | wipe our 6-mil stencil each pass to get the paste in the 20-mill pitch | aperatures for a QFP to release well. We are using Amtech NC-559 type 3 | paste with
Electronics Forum | Fri Sep 21 14:03:45 EDT 2001 | jschake
I have observed solder balling for all aperture sizes tested. Solder balling levels appear to be better correlated against the amount of solder paste that is underneath the 0201 component terminations after placement rather than comparing this to th
Electronics Forum | Wed Sep 22 21:12:16 EDT 1999 | se
| | | | My stencil thickness is 6 mil and we got qfp's with fine pitch. | | | | how many percent should i reduce my stencil aperture using a 6 mil stencil for 0.5 mm pitch and 0.4 mm pitch ? | | | | | | | | thanks | | | | | | | We use 6 mil lasercu
Electronics Forum | Wed Jan 13 07:37:45 EST 1999 | EFData
We have evaluated using WS-629 and our feelings are that the formula is not very stable. One evaluation showed great results; superior solder joint appearance and good printability. The paste would not roll on another evaluation nor would it release
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