Printed circuit board and manufacturing method thereof

Abstract

The invention provides a manufacturing method for a copper pillar of a PCB. The manufacturing method comprises the steps that a first copper foil layer is formed on the first surface of a carrier; the first copper foil layer is etched to form a first copper pillar, and a part of the first surface is exposed; an anti-adhesion material layer is formed on the exposed part of the first surface, and the first copper pillar is exposed; a dielectric layer is formed on the anti-adhesion material layer and the first copper pillar; a hole is formed in the position, corresponding to the first copper pillar, of the dielectric layer, and the first copper pillar is exposed; a second copper pillar connected with the first copper pillar is formed in the position where the hole is formed, and a first copper layer connected with the second copper pillar is formed on the dielectric layer; the carrier and the anti-adhesion material layer are removed; then copper plating is conducted, and an outer-layer circuit is manufactured, so that the PCB is manufactured. The invention further provides the PCB with the protruding copper pillar manufactured based on the method. The protruding copper pillar manufactured based on the method has higher reliability during welding.

Description

technical field [0001] The invention relates to the field of printed circuit boards (PCBs), in particular to a method for manufacturing a PCB and a copper column thereof. Background technique [0002] Since the solder joints are getting smaller and smaller, in order to improve the soldering yield and reliability, it is proposed to replace the original plane soldering process with bump soldering. Bump soldering is to form a raised copper pillar on the surface of the package substrate as a soldering point for soldering. Bump soldering can solve the problem of virtual soldering caused by uneven flatness and uneven thickness of solder mask in traditional plane soldering, and can adapt to high-density packaging requirements. [0003] The copper column manufacturing method in the related art is to paste a dry film on the surface of the substrate, open a window, and then plate copper to form the copper column. Due to the uneven current density during copper plating, the copper pi...

AI Technical Summary

Problems solved by technology

Due to the uneven current density during copper plating, the copper pillars produced by copper plating are uneven, and the dry film on the surface of the substrate cannot be leveled. Therefore, the copper pillars produced by this method cannot meet the requirements of modern soldering and packaging.

In addition, since the copper pillars protruding from the surface of the substrate, they cannot be effectively protected during subsequent processing and are easy to fall off; it is also difficult to make circuit patterns on the substrate surface with copper pillars formed, and the substrate space cannot be effectively used.

Based on the above series of problems, the process of bump welding by welding copper pillars cannot be applied and promoted

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