Solder Mask Defined and Non-Solder Mask Defined in PAD - Digikey.com Navigation and Terminology - Engineering and Component Solution Forum - TechForum │ Digi-Key
WHAT IS SOLDER MASK?
pcb - Why some vias have solder mask and others do not? - Electrical Engineering Stack Exchange
Solder Mask Expansion | Online Documentation for Altium Products
Difference Between Via Tenting and Via in Pad - Bittele
Solder Mask Expansion from Hole (New Feature Summary) | Altium Designer 15.1 User Manual | Documentation