Patent ID: 6214642
Filing Date: 2001-04-10
Classification: H01L

Abstract:
A method for producing a flip chip device, said flip chip device containing a chip having an active surface with a central active area and a peripheral area, the central active area having at least one I/O pad thereon, a substrate having opposing first and second surfaces, said first surface having at least one substrate I/O pad corresponding to said chip I/O pad, said chip I/O pad and said substrate I/O pad electrically interconnected by a stud bump interconnection, said second surface having at least one exterior I/O pad electrically connected to the corresponding substrate I/O pad; said method comprising the steps of:forming the stud bump on the I/O pad on the first surface of said substrate, said forming comprising the steps of:forming a ball at a tip of bonding wire;bonding said ball to the I/O pad on said first surface of the substrate by a wire bonding method; andfracturing the wire at a point proximate the bonded ball to form the stud bump on the I/O pad on said first surface of said substrate, said stud bump adapted for interconnection with said I/O pad on said chip;applying at least one layer of interface metallurgy on the I/O pad of the chip;aligning the chip I/O pad with the stud bump on the I/O pad on said first surface of said substrate; andafter the step of forming the stud bump, assembling the device by joining the I/O pad on said chip to the stud bump on the I/O pad on said first surface of said substrate to form an electrical interconnection between the I/O pad on said chip and the I/O pad on said first surface of said substrate.