Circuit board and manufacturing method thereof

Abstract

The invention relates to a circuit board. The circuit board comprises a flexible circuit board and a shielding grounding structure formed on the surface of the flexible circuit board; the flexible circuit board comprises a dielectric layer as well as a first conductive line layer and a second conductive line layer which are formed at two opposite sides of the dielectric layer; a conductive hole which penetrates through the dielectric layer is formed in the dielectric layer; the first conductive line layer is electrically connected with the second conductive line layer through the conductive hole; a first insulating covering layer is formed on the surface of the first conductive line layer; first openings are formed in the first insulating covering layer so as to expose a part of the first conductive line layer, so that first grounding pads can be formed; the shielding grounding structure comprises a copper layer, an anti-welding layer and a gold layer; the copper layer covers the surface of the first insulating covering layer and the surfaces of the first grounding pads, and fills the first openings; the anti-welding layer covers the surface of the copper layer; second openings are formed in the anti-welding layer and expose a part of the copper layer, so that second grounding pads can be formed; and the gold layer covers the surfaces of the second grounding pads. The invention also relates to a manufacturing method of a circuit board.

Description

technical field [0001] The invention relates to a circuit board and its preparation method. Background technique [0002] In order to prevent the circuit board from emitting electromagnetic radiation during operation and interfering with the normal operation of other electronic components, a shielding grounding structure is usually selectively provided on the circuit board. [0003] At present, setting the shielding grounding structure on the circuit board can be achieved by the following methods: first, the shielding conductive cloth with anisotropic conductive adhesive and the grounding conductive cloth with metal conductive particles are cut into the required shape; then, on the circuit board The area that needs to be shielded and grounded is first pasted with a layer of the shielded conductive cloth, and the anisotropic conductive adhesive is electrically connected to the circuit board; then, the position is first aligned on the shielded conductive cloth and then thermal...

AI Technical Summary

Problems solved by technology

Since the grounding conductive cloth needs to be aligned when it is hot-bonded and hot-pressed to the shielding conductive cloth, and the lamination accuracy of the machine or manual is limited, in order to make the alignment accurate and ensure good lamination accuracy, the The size of the shielding conductive cloth and the grounding conductive cloth has certain requirements, that is, the bonding size of the shielding conductive cloth and the grounding conductive cloth is limited by the bonding accuracy

This will result in limited placement of the shield grounding structure

In addition, the grounding conductive cloth is electrically connected to the circuit board through the anisotropic conductive glue, so that the grounding resistance is relatively large, which affects the shielding effect

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