Gold Finger Soldering Layer Opening

For the edge connector (gold finger) area, the solder mask layer should be completely opened and exposed.

If the solder mask is only partially opened or covers only the gold finger area, it may peel off or crack during insertion and extraction, resulting in surface contamination, poor contact, and even damage to the edge coating. When edge beveling, if there is still residual solder mask in the gold finger area, it may also be mechanically scratched or lifted, causing uneven edges or detachment, thereby affecting the appearance and performance.

We suggest that regardless of whether the gold finger area has undergone chamfering treatment or not, the entire contact area of the gold finger should be fully opened up until the edge of the board. This ensures a smooth chamfer, a clean contact surface, and maintains the adhesion and wear resistance of the gold plating layer on the gold finger.

When generating the Gerber files, please ensure that the exposed area of the solder mask covers the entire top and bottom layers of the gold finger area.