The conductive hole Viahole is also called conductive hole. In order to meet customer requirements, the conductive hole of the circuit board must be plugged. After a lot of practice, the traditional aluminum chip plugging process has been changed, and the white screen is used to complete the solder resistance and plug hole on the PCB board surface. Stable production and reliable quality.

Viahole plays the role of connecting and conducting lines. The development of the electronic industry also promotes the development of PCB, and puts forward higher requirements for PCB manufacturing process and surface mounting technology. Viahole plug hole process emerged as the times require, and the following requirements shall be met at the same time:

Copper in the through hole can be used, but plug can be used for resistance welding;

There must be tin lead in the through hole, with a certain thickness requirement (4 microns). Solder blocking ink is not allowed to enter the hole, causing tin beads to be hidden in the hole;

The through hole must be provided with solder blocking ink plug hole, which is light tight, without tin ring, tin bead, flatness and other requirements.

With the development of electronic products in the direction of "light, thin, short and small", PCB is also developing towards high density and high difficulty, so a large number of SMT and BGA PCBs appear. Customers require plug holes when mounting components, which have five main functions:

Prevent short circuit caused by tin penetrating through the component surface from the through hole during wave soldering of PCB; Especially when we put vias on BGA pads, we must make plug holes first, and then gold plating to facilitate BGA welding.

Avoid flux residues in the through hole;

After the surface mounting and component assembly of the electronics factory are completed, the PCB must be vacuumed on the testing machine to form a negative pressure:

Prevent the solder paste on the surface from flowing into the hole, causing false soldering and affecting the mounting;

Prevent solder beads from popping up during wave soldering, causing short circuit.