Laser-formed connections using polyimide

Electrical connections have been formed in a new lateral link structure which uses polyimide in the gap between, and overlapping, two aluminum electrodes. An argon ion laser, with a pulse width of 1 ms and power levels of about 2 W, was used to locally graphitize the polyimide. One kilohm connections were formed reliably in links ranging in width between 4 and 15 μm and gap length between 2 and 5 μm. This technique is the simplest yet proposed for restructuring the connections on an integrated circuit, after fabrication and test, in order to incorporate redundancy for yield improvement.