Studded chip attachment process
AssigneeInternational Business Machines Corporation
InventorsKailash C. Joshi, Ronald N. Spaight
Life of this patent
Estimating the term…
Abstract
A plurality of metal studs are plated on a chip carrier surface in a pattern to match a terminal metal footprint on a chip to be joined. The studs are of sufficient height to permit flux cleaning, if necessary. After the studs are in place, the chip is aligned with the carrier and attached thereto, the chip pads containing a small amount of solder to provide the connecting joints. The carrier and chip are made of materials having nearly equal thermal expansion characteristics.
Claims8
A method of bonding a first integrated circuit device having a number of connecting points to a second integrated circuit device having a like number of connecting pads, both first and second devices having approximately equal thermal expansion characteristics, said method comprising the steps of:
- fabricating a metal stud at each of said connecting points of said first integrated circuit device, the top of each stud providing a bondable surface;
- applying a amount of solder not exceeding 4.times.10.sup.-3 centimeters thick to each of said connecting pads of said second integrated circuit devices;
- aligning said first and second integrated circuit devices so that each metal stud of said first device is positioned proximate its respective connecting pad of said second device;
- and
- applying sufficient pressure and temperature to the studs and pads to bond each of said studs to its respective connecting pad.
Dependencies are inferred from the claim text.