PCB via is one of the vital components of a multilayered printed circuit board. The 30 to 40 percent of board cost is estimated to be spent on drilling process.
What exactly is via? It is common knowledge that a copper foil layer upon layer superimposes PCB. That connection that exists among different circuit layers is via.
The three most common of PCB via are given below:
a. Plating Through Hole (PTU):
This is one of most common types of via. A method to check it is to take up the PCB and put some light on it. If you are able to see the light, it is “through hole”. PTH is also known to be simplest kind of hole. The reason is because of little effort which consists of using a drill or laser light for making a complete borehole. That being said, PTH is also cheap. However, PTH can sometimes use more PCB space.
b. Blind Via Hole:
When the outermost circuit of PCB is connected to adjacent inner layer with PTH, we get a blind pass. The specific name is given because of fact that the opposite cannot be seen. The blind via hole is created to increase space utilization of PCB circuit layer. For successfully producing an effective blind hole, depth of hole requires attention. It should be appropriate. It is worth mentioning that almost all of PCB viamanufacturers avoid this method due to its difficulty.
c. Buried Via Hole:
This type of PCB viais connection to any of the circuit layer while not extending to outer layer. It is impossible to do this process using bonding after drilling. It must in individual layer of circuit. This is to happen when drilling is implemented after the first part of internal bonding is done after first plating treatment, after which final bonding is given shape. Buried via hole is more expensive and needs more time in its manufacturing.