BRIMAN1
07-26-2004, 05:42 PM
I am working on a 289 pin .5mm bga and was hoping to get advice on micro via sizes. Right now I am using a 4mil laser drilled via with a 12 mil pad from 1-2. Then I am using a 12 mil burried via from 2 to 3. I do have some mechanical drilled vias from 1 to 10 but I am trying to keep them to a min. since I have 2 zbc-2000 cores and want the burried capacitance planes to be as solid as possible. My question is what is the min. spacing from blind to buried via from center to center in a hdi staggerd via arrangement? Some fab houses have told me 6 mils, while another one has told me that would be unreliable.
briman1
briman1