"Improvement of C-4 Chip Soldering Process"
Original Publication Date: 1989-Aug-01
Included in the Prior Art Database: 2005-Jan-30
In the fabrication of circuits on organic films such as polyimide, copper pads are provided for attachment of a semiconductor chip or other such electronic device. One of the major problems in chip joining by C-4 soldering process is the oxidation of the copper pads. It is very difficult to prevent the oxidation because of the trace oxygen (few ppm) and water vapor from the environment of the furnace where chip joining occurs.