Circuit board

A circuit board, comprising:

• a circuit structure, comprising:
• a substrate having a first side, a second side opposite to the first side, and a side surface;
• an insulating structure, disposed above the first side of the substrate, wherein the insulating structure comprises a first insulating layer, a second insulating layer and a third insulating layer, the second insulating layer is located above the first insulating layer, and the third insulating layer is located above the second insulating layer;
• and
• a pad structure, located in the insulating structure, wherein the insulating structure comprises an opening located on the pad structure and a removal region located between the pad structure and the side surface of the substrate, wherein at least a portion of the insulating structure in the removal region is removed, a horizontal distance between the removal region and the pad structure is H, 0<H≤10 micrometers, the second insulating layer and the third insulating layer in the removal region are completely removed, and the side wire is in contact with a sidewall of the removal region and the first insulation layer located at a bottom surface of the removal region;
• and
• a first planarization layer, a second planarization layer and a third planarization layer stacked in sequence, wherein the first insulating layer extends between the first planarization layer and the second planarization layer, the second insulating layer extends between the second planarization layer and the third planarization layer, and the third insulating layer is formed above the third planarization layer;
• and
• a side wire, filled in the opening of the insulating structure and extending from the pad structure to the second side of the substrate.