Multilayer flexible printed circuit board and method of manufacturing the same

Abstract

The invention provides a multilayer flexible printed circuit board and a manufacturing method thereof. The multilayer flexible printed circuit board comprises a circuit board and a grounded conductive reinforcement, wherein, the circuit board is formed by a plurality of single layer flexible printed circuit boards which bond together, each single layer flexible printed circuit board is provided with copper foil and a cover membrane which is positioned on the copper foil, wherein, a windows is welded on the cover membrane of the outer layer of the multilayer flexible printed circuit board and corresponds to the grounding position needing welding and conductive reinforcement; a copper-plating block is welded on the single layer of flexible printed circuit board and corresponds to the grounding position needing welding and conductive reinforcement, the copper-plating block protrudes out of the window of the cover membrane; and the conductive reinforcement is conducted with the copper-plating block through a conductive adhesive. The multilayer flexible printed circuit board can decrease the height difference between the conductive reinforcement grounding position and the cover membrane, reduces the height of the circuit board and the conductive reinforcement which are attached with each other through a conductive adhesive, reduces the grounding resistance of the conductive reinforcement, and improves the yields of the product.

Description

【Technical field】 [0001] The invention relates to a multilayer flexible printed circuit board and a manufacturing method thereof. 【Background technique】 [0002] The multi-layer flexible printed circuit board is formed by adding an adhesive between layers of a single-sided flexible printed circuit board or a double-sided flexible printed circuit board, and hot pressing to cure the adhesive to achieve firm bonding between the layers. With the development of miniaturization and light weight of various electronic equipment, it is required to have small size, high heat resistance, low resistance, good shielding effect, flexible printed circuit board with superior bending performance and multi-function. In order to ensure the bending performance of multilayer flexible printed circuit boards, copper plating with hole patterns is generally used. In order to ensure the hardness and stability of multilayer flexible printed circuit boards SMT (Surface Mount Technology, surface mount t...

AI Technical Summary

Problems solved by technology

[0005] The steel reinforcement 2' of the above-mentioned multi-layer flexible printed circuit board needs to be grounded, and it is connected to the copper foil 11' of the circuit board 1', and there is a cover film 12' between them. Since the cover film 12' has a height, it is conductive The thickness of the glue 3' is not enough, so the resistance is generally very large, and it will even be insulated after reflow soldering, which will reduce the yield rate of the product. Taking mobile phones as an example, it will seriously affect the display function of the mobile phone

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