A 0.25~ rn VIA PLUG PROCESS USMG SELECTIVE CVD AL.IMTNOM FOR MULTILEVEL INTERCONNECTION

A multilevel interconnection with 0.25 0 m via holes has been successfully fabricated using a selective CVD aluminum via plug process. Via holes on first level aluminum interconnections have been fully plugged for the first time by selective CM aluminum in combination with in situ RF cleaning. Specific contact resistivities of CM aluminum via plugs are estimated to be as low as 5~10-l~ R cm2 and the yield for LO4 via chains is 100% for test patterns with various via diameters of 0.25-2~ m. Electromigration tests for the CVD aluminum plugs demonstrate extremely high reliability compared to conventional sputtering samples.