Dear Members, We have serveral very high density PCB with microvias on pads, the microvia is 4 to 5 mil, recently, our SMT house tell us two components contains microvia on pad are tombstoning after reflow sporadically, and maybe the reason is the pad with microvia on it need more solder when printing, since there is a hole on pad, so the stress is unblanced during reflow, thus tombstone occured.
Does any one have more experience on this? if you use microvia on pad in your design? I heard copper-Filled Microvias before, No holes observable after plating, but I do not know how to do this, where can I find more technical paper about this? Is it very expensive? Your input is very appreciated! Best Regards, Luo. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[EMAIL PROTECTED] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
