1. Through hole: PlatingThroughHole, referred to as PTH

This is the most common and simplest kind of through-hole, as long as the PCB is held up to the light, the light of the hole is through-hole. Because through hole production as long as the use of drill or laser light directly to the circuit board to do all the drilling can be, so the cost is relatively low. Through holes are cheap, but sometimes take up more PCB space.

2. BlindViaHole (BVH)

Connect the outermost circuit of PCB with the adjacent inner layer by electroplating hole, because you can’t see the opposite side, so it is called blind hole. In order to increase the space utilization of PCB circuit layer, the blind hole process came into being. PCB proofing this production method needs to pay special attention to the depth of drilling to be just right, can be connected in advance of the circuit layer in individual circuit layer drilled well, and finally glued together, but need more precise positioning and positioning device.

3. Buried hole: BuriedViaHole (BVH)

This refers to the connection of any circuit layer inside the PCB but not to the outer layer. This process cannot be achieved by drilling after bonding. Drilling must be carried out at the time of individual circuit layers. Firstly, the inner layer is partially bonded and then electroplating is required before all bonding can be done. This process is typically used only on high density (HDI) circuit boards to increase usable space on other circuit layers.