Heat spreader with a placement recess and bottom saw-teeth for connection to ground planes on a thin two-sided single-core BGA substrate

摘要

The present invention discloses a new semiconductor ball grid array package for integrated circuits which have input and output counts higher than 250. The speed and performance characteristics of the semiconductor device contained in the package assembly are optimized while the packaging structure is simplified by utilizing only one dielectric layer and regular printed circuit board fabrication process. The complexities and higher cost for production of a multiple layer substrate for high-density interconnection configuration are thus resolved. The improved package assembly is achieved by implementing a segmented ring on one side of a substrate and a split plane on the other side thus forming a single layer substrate structure. The edges of the substrate are coated with metal layer to provide interlayer connections. The package assembly applies a cavity down configuration with an integrated heat spreader attached. The IC wire bonds within the cavity are sealed with an organic encapsulant. In addition to the benefits of high performance low cost, the improved circuit structure and package layout provide flexibility allowing higher degree of freedom for selecting the location and number of input and output signal lines and connections to the ground and power planes from the semiconductor device.