More than half of the integrated circuits manufactured in the world have wire leads attached by the ball-bonding process. Almost all of the information about this process is empirical--an analytical model does not exist. In the attachment process the bonding wire is heated by an electric discharge; it then melts and forms a ball under the influence of surface tension. The ball is pressed onto the contacts on the silicon chip to form a bond. The researcher will study ball formation by scaled-up experiments, using high-speed motion pictures. Gold wire in air, and aluminum alloy wire in air and in argon will be used. The alloy will contain magnesium as the strengthening agent, but other alloys will also be evaluated.
