Browse Prior Art Database

Gold-Copper-Gold Plating

IP.com Disclosure Number: IPCOM000115312D
Original Publication Date: 1995-Apr-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 26K

Publishing Venue

IBM

Related People

Edwards, RD: AUTHOR [+2]

Abstract

Disclosed is an enhanced process for applications requiring thick soft gold deposits, such as gold studs for gold-gold compression bonding or gold-gold/tin. This process significantly reduces the cost of the plating process, while not affecting final usefulness of the gold.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Gold-Copper-Gold Plating

      Disclosed is an enhanced process for applications requiring
thick soft gold deposits, such as gold studs for gold-gold
compression bonding or gold-gold/tin.  This process significantly
reduces the cost of the plating process, while not affecting final
usefulness of the gold.

      It is possible to replace a solid thick gold deposit with one
that has Acid Copper Sulfate plated copper replacing the middle of
the deposit.  Gold is deposited to a thickness of at least 7 microns
on either side of the copper, which is plated to whatever thickness
is required for the application.  During high temperature bonding,
copper is seen to migrate no more than 3 microns into the gold.
Thus, by maintaining a gold thickness of greater than 7 microns on
each side of copper, sufficient pure gold is available for the
bonding application.

      In addition to being a much less expensive metal deposit, the
Acid Copper plating provides better levelling, plating thickness
distribution, and 10% better conductivity.