Patent ID: 7224073
Filing Date: 2007-05-29
Classification: H01L,H05K,Y02P

Abstract:
1. A substrate for solder joint, comprising: a core layer; at least one conductive trace formed on a surface of the core layer and having a circular terminal that serves as a pad through which a plurality of hollow portions are formed and thereby expose predetermined portions of the core layer underneath the pad, wherein the hollow portions are arranged at equal intervals and spaced from a periphery of the circular pad; and a solder mask applied over the surface of the core layer for covering the conductive trace, and formed with at least one opening that corresponds in position to the circular pad and is sized smaller than the pad, the opening being bordered across each of the hollow portions of the pad, such that part of the pad and part of each of the predetermined portions of the core layer are exposed via the opening, while the rest part of the pad and the rest part of the predetermined portions of the core layer are covered by the solder mask, so as to allow a conductive element to be bonded to the exposed part of the pad and the exposed part of the predetermined portions of the core layer in the opening of the solder mask.