Patent ID: 7109067

Claim:
A method for fabricating a semiconductor device, comprising: forming first conductive pads on a bottom surface of a chip-mounting substrate; roughening said bottom surface of said chip-mounting substrate; after said roughening said bottom surface of said chip-mounting substrate, etching said bottom surface to expose said first conductive pads; mounting a semiconductor chip on atop surface of said chip-mounting substrate; connecting said semiconductor chip with said first conductive pads electrically; forming solder balls on said first conductive pads; assembling said chip-mounting substrate onto a printed circuit board by connecting solder balls with second conductive pads formed on said printed circuit board; and injecting underfill material into a clearance formed between said chip-mounting substrate and said printed circuit board, wherein said roughening said bottom surface comprises shaping said bottom surface to include indentations for improving an adhesive strength of said underfill material, wherein said injecting said underfill material comprises injecting said underfill material into said indentations of said bottom surface of said chip-mounting substrate, and wherein said roughening said bottom surface of said chip-mounting substrate comprises roughening a surface of a solder mask of said chip-mounting substrate.