FORMATION OF SINGLE-CRYSTAL AL INTERCONNECTION BY IN-SITU ANNEALING

A new process for forming Al interconnections on amorphous insulators such as SiO2 is proposed in this paper. Al thin films were found to ag glomerate at temperatures below the melting point and to fill the groo ves on a SiO2 layer by in situ annealing in which native oxide is only minimally formed on the Al surface. In sufficiently deep grooves, sin gle-crystal Al interconnections were successfully formed without used of Al dry etching. It has been clearly confirmed by acceleration testi ng that single-crystal Al interconnections formed by means of the pres ent process have excellent endurance against electromigration compared with conventional poly-crystal interconnections.