Via Specification

Cover the vias with solder mask

The vias have not be opened on the solder mask layer

in the gerber file, and when we cover the board with 

solder mask, there will have some solder mask oil flow 

into the via and the via will be covered by solder mask

finally.

Suitable for the via which only use

for conductive and no any other 

special requirement.

Open the vias on solder mask

The vias have been opened on the solder mask layer 

in the gerber file, and when we cover the board with 

solder mask, the solder mask will shy away from the vias

and will expose the copper of the vias.

Suitable for the via which need 

have good heat dissipation or use

for test.

Plugged via/via-in-pad

The via with a solder pad above it in the gerber file. 

And the via will full fill with solder mask oil or resin 

before we cover the board with solder mask.

Suitable for the design which need 

to put some pads above the via and

use for soldering.