Thermal performance improving for small form factor BGA

The thermal consumption of IC package becomes getting higher and higher when the device is running at full speed in a tiny space, especially the IC packages become toward small form factor, light weight, high I/O, more functionality and systems integration. The HSBGA (Heat Slug BGA) has hat-type heat slug added on the top side of BGA package to enhance package thermal performance and it is a cost effective in assembly process by simply adding a heat slug. The hat-type HSBGA is most used for large package due to needs of more space to accommodate the heat slug. Recently, a flat-type heat slug has been used to replace hat-type heat slug and it is called “aHSBGA”. The aHSBGA can reduce the package size and thickness because of no boundary limitation for wire bonding fingers. In this study, the challenges of assembly processing will be discussed. A 21×21mm aHSBGA 572Lead is used as a test vehicle for process study, qualification and the reliability test. The package thermal data comparisons and the warpage simulation and measurement are discussed as well.