Hi Alexis, What about using a soldermask defined opening? You could increase the pad size for the annular ring aspect but use the soldermask to limit the solder area to 11mils. Just a thought. Bob McCreight --- On Thu, 7/26/12, ameehan@xxxxxxxxxxxxxx <ameehan@xxxxxxxxxxxxxx> wrote: From: ameehan@xxxxxxxxxxxxxx <ameehan@xxxxxxxxxxxxxx> Subject: [PCB_FORUM] Via Size To: "ICU" <icu-pcb-forum@xxxxxxxxxxxxx> Date: Thursday, July 26, 2012, 9:15 AM #yiv967566037 body{font-family:Geneva, Arial, Helvetica, sans-serif;font-size:9pt;background-color:#ffffff;color:black;}Good morning group! We’re working on a design that has several .5mm pin pitch BGA’s. In order to route it, we’ll have to use via-in-pad technology (and maybe even blind vias). The mounting pad is only 11 mils dia (.28mm), and the board is 50 mils (1.27mm) thick. Our smallest via currently has a 6 mil hole, but that won’t leave enough annular ring with a 11 mil pad. What have you folks used for this type of part? I've also forwarded the question to our fab houses to get their feedback, but wanted to know what your experience has been. Thanks. Alexis Meehan Violin Memory Inc ----------------------------------------------------------- To subscribe/unsubscribe: Send a message to icu-pcb-forum-request@xxxxxxxxxxxxx with a subject of subscribe or unsubscribe To view the archives of this list go to //www.freelists.org/archives/icu-pcb-forum/ Problems or Questions: Send an email to icu-pcb-forum-admins@xxxxxxxxxxxxx -----------------------------------------------------------