Optiprint is the ideal partner for miniaturization. A modern machinery guarantee the processing of thinnest materials (as fr om 12.5µ) in the cutting.
Micro vias which are laser or mechanical drilled can be filled with copper by plated thorugh-hole. Stacked vias and via-in-pad technology are basic requirement in the miniaturization.
Last but not least there are two universal surface finish (ISIG and ENEPIG) available for all assembly techniques. Micro BGA, Flip-Chip, wire bonding, Chip on Flex - and these are only a few keywords.
Picture shows a miniaturization PCB from Optiprint AG