REVIEW OF PLANARIZATION AND RELIABILITY ASPECTS OF FUTURE INTERCONNECT MATERIALS

Device linewidths are shrinking resulting:in more stringent requiremen ts on choice of materials,, processes and designs. Current generation of memory and microprocessor designs use tungsten as the main intercon nect material with aluminum being utilized in lines. It is being propo sed-at the current time that copper and aluminum will be,likely candid ates for the future interconnect structures. Although both metals are equally suitable as the next generation interconnect,: there still exi st certain material issues relating to deposition, electromigration/re liability, and planarization that need to be addressed.