Patent ID: 8058564
Filing Date: 2011-11-15
Classification: H01L,H05K

Abstract:
1. A circuit board surface structure, comprising: a circuit board having at least one surface provided with a plurality of electrically connecting pads; an insulating protective layer characterized by photosensitivity and solder resisting and formed on a surface of the circuit board; openings formed in the insulating protective layer to expose the electrically connecting pads on the circuit board, the openings being tapered upward, wherein each of the openings has a top part and a bottom part, and a projected area of the top part is smaller than a projected area of the bottom part; and a conductive element formed in the opening of the insulating protective layer by electroplating for electrically connecting with the electrically connecting pad, wherein the opening tapered upward enables a relatively large contact area between the conductive element, the electrically connecting pad and the opening, and a portion of the conductive element is gripped by the insulating protective layer through the opening, thereby increasing capacity for shear stress, enhancing bonding strength and avoiding detachment of the conductive element.