Electronics Forum | Mon May 10 16:37:01 EDT 2004 | davef
First some definitions, the two main types for solder masking near BGA pads are: 1 Pad, Non-Solder Mask Defined. In circuit board design, pads with spacing that does not allow solder (usually bumps) on the pads to contact the adjacent solder mask. [
Electronics Forum | Tue May 25 07:03:34 EDT 1999 | Milan Z.
After reflow proces in convection-IR oven we find broken body of SOT23 elements. There is no problems on other elements (SOIC, chip R,chip C, etc) Where is the problem? Thanks in advance!
Electronics Forum | Wed May 26 18:04:16 EDT 1999 | John Thorup
| After reflow proces in convection-IR oven we find broken body of SOT23 elements. There is no problems on other elements (SOIC, chip R,chip C, etc) | Where is the problem? | | Thanks in advance! | Check your profile at the site of cracked component
Electronics Forum | Mon May 10 11:24:33 EDT 2004 | Charly
Encounter solder ball crack after reflow, found the solder ball is out of shape after reflow, cross section view found that the solder mask opening is not good ( when we do comparason with diff. supplier substrate.) Does the solder mask shape will af
Electronics Forum | Fri Sep 04 02:27:48 EDT 2009 | hurr
Hallo all, when I remove one from us malfunction BGAs from PCB I saw under X-ray inspection inner hairline crack.(see fig.1.) BGA was dried according to J-STD 033 and reflowed in lead process. When I look at new (baked BGA) under X-Ray inspection I
Electronics Forum | Thu Sep 12 01:49:28 EDT 2002 | ck
Hi all, Any stencil opening recommendation for 20mils pitch mirco BGA. Currently, using 12mils round opening, 5 mils thickness. Seen to have weak joints as it crack after Ict testing. thks
Electronics Forum | Thu Sep 12 09:15:29 EDT 2002 | mhoughton
I have printed and placed similar devices in high volume with exactly this spec for a couple of years with no problems, are you using laser cut stencils and what type of solder paste are you using? and what is the end use of the product as it may nee
Electronics Forum | Thu Sep 12 10:45:29 EDT 2002 | pbarton
We have used a laser cut stencil 0.15mm (0.006") thick with 0.3mm (0.012") square apertures radiused in the corners 0.06mm (0.0025") to aid paste release. This approach with the (type 3) paste we use has proven successful on thousands of devices plac
Electronics Forum | Wed Jan 17 20:48:14 EST 2001 | davef
We find that the raw BGA's pad sheared surface has the SnPb solder at various Z heights whereas the assembled BGAs pad leave a smooth layer of SnPb along the pad. Like to understand the cause for the difference. Who could guess? Solder joint streng
Electronics Forum | Mon Nov 06 21:06:13 EST 2000 | Dave F
Thomas: Wheeee, a 40% failure rate. Now, that make your boss chase you around the room won�t it? As you indicated, x-ray won�t do dip about helping to identifying problems [or ball cracks either]. Consider using an ERSA scope [er whatever they ca
