What Are Blind and Buried Vias in PCB?
Although some information about circuit board prototype design has been around for some time, getting direct answers can be confusing. There is a lot of information out there, and even the most experienced engineer may have difficulty distinguishing whether the information about their particular prototype PCB is right or wrong. One example is the difference between blind and buried vias in circuit boards.
The following is all the information about what is blind and buried vias technology in PCB.
Ⅰ. What are blind vias and buried vias?
We all know that the copper track on the printed circuit board is a conductive path used to connect two points in the PCB.
1. Blind vias channel
Blind vias are copper-plated vias that are only interconnected with one outer layer of the PCB. However, it is important to know that the via does not reach the circuit board all the way, making it "blind" or "invisible" to naked eyes.
2. Buried vias channel
On the other hand, buried vias connect at least two layers without reaching the outer edge of the board. Therefore, it is buried in the circuit and completely internal.
Ⅱ. Other useful information about blind and buried vias in prototype PCB manufacturing
Generally speaking, these two types of through holes are used for higher-density circuit boards, because simple circuit boards do not actually require different design structures for they are composed of only one layer.
1. Blind vias channel
The via of the blind via must be defined by a separate drill bit, and the ratio of the via diameter to the drill bit diameter must be less than or equal to 1. The smaller the via, the smaller the distance between the outer layer and the corresponding inner layer will be. Each via has an inner layer.
2. Buried vias channel
Because these buried vias are used to connect different parts of the inner layer of the prototype circuit board, each via must be made from a separate drill file.
