Circuit board and manufacturing method thereof

A manufacturing method of a circuit board, comprising:

• stacking a copper foil on a surface of an insulating layer to form a copper foil layer,
• forming a via hole to penetrate the insulating layer and the copper foil layer,
• plating on the copper foil layer and an inner wall of the via hole to form a through via forming portion,
• forming a plug to fill an inner space of the through via forming portion,
• forming a first mask pattern at a region disposed along an edge of the via hole on the through via forming portion,
• etching an exposed portion by the first mask pattern to form a through via,
• forming a second mask pattern to expose a region disposed on the through via and the plug, and a region disposed on a portion of the insulating layer spaced apart from the region on the through via, and
• forming a circuit layer by plating on the regions exposed by the second mask pattern.

A manufacturing method of a circuit board, comprising:

• forming a via hole to penetrate an insulating layer,
• forming a third mask pattern on the insulating layer to expose a region disposed along an edge of the via hole,
• plating along the exposed region and an inner wall of the via hole to form a through via,
• forming a plug to fill an inner space of the through via,
• forming a fourth mask pattern to expose a region disposed on the through via and the plug, and a region disposed on a portion of the insulating layer, and
• plating on the regions exposed by the fourth mask pattern to form a circuit layer.