HDI PCB means high density interconnect printed circuit board which is also known by Build-up PCB. HDI PCBs have more finer lines and spaces, micro vias such as buried or blind via, smaller capture pads, and higher connection pad desity. Different from conventional PCB, HDI PCBs use laser drilling equipment to achieve the via requirement of buried and build vias. High density interconnect PCB makes the end product more efficient and allow for faster transmission.