Circuit board

A circuit board comprising:

• an insulating structure including a plurality of insulating layers stacked along a vertical direction;
• a primer layer disposed in the insulating structure;
• a circuit pattern disposed on the primer layer;
• a via electrode disposed on a lower surface of the circuit pattern;
• and
• a protective layer disposed on the circuit pattern and the primer layer,
• wherein the protective layer includes a first portion having a first thickness along the vertical direction and a second portion having a second thickness greater than the first thickness along the vertical direction,
• wherein the primer layer has a third thickness smaller than the second thickness of the protective layer along the vertical direction,
• wherein the circuit pattern includes a plurality of pad portions disposed on the primer layer and penetrating the first portion of the protective layer along the vertical direction, and
• wherein the via electrode includes a plurality of vias penetrating the primer layer and at least a portion of the insulating structure along the vertical direction and being in contact with a lower surface of each of the plurality of pad portions.