Q:What is the blind via PCB or buried via PCB?What are the differences between them?
A：From the end of 20th century to the beginning of 21st century, circuit board electronic industry has achieved a great technological improvement and thus technology of electronics has rapidly upgraded.Our PCB board company has to develop in the same pace with it so as to satisfy the customers’ need.With electronic products getting smaller,lighter and thinner, new kinds of PCB are developed flexible PCB, rigid PCB, blind via PCB, buried via PCB.
When talking about blind and buried vias,we start from the traditional multi-layer PCB.The standard multi-layer printed circuit board structure consisting of inner circuits and outer circuits is made by manufacturing operations of drilling and metalization within vias to realize the inner connection of all layers of circuits.However,because of the increasing of circuit density and ceaseless update of the ways to package parts, in order to put more higher- efficiency parts in limited PCB space, the via diameter is also shortened from 1mm to 0.6mm, and further to below 0.4mm besides the measures to make the width of circuits thinner.But it still takes up superficial space,thereby blind and buried vias are produced. Here are their definitions:
It is the through hole between inner layers,which can’t be seen after pressing so the outer space is spared. Both sides of the hole are in inner layers, meaning it is buried inside the board.
It is the through hole applied in the superficial layer and one or more inner layers.One side of the via is in one side of the board,and extends to the inside of the board.