Reliability of built in aluminum interconnection with low-epsilon dielectric based on porous anodic alumina

In order to enhance the reliability of silicon ICs, an electrochemical anod izing technique was used to form an intralevel alumina insulator for multil evel aluminum metallization. The low dielectric constant of about 2.4 was a ttained by chemical etching of porous alumina films in an anodizing solutio n. The intralevel insulator based on porous alumina had the following param eters measured: the breakdown voltage was more than 400 V, the leakage curr ent at 15 V applied voltage was less than 10(-9) A/cm(-2). An investigation of thermal overheating at high current density operation has shown that th e developed structure offers advantages over aluminum interconnection passi vated by silica insulator. The reliability of built in aluminum interconnec tion with low-E porous alumina satisfies all requirements of advanced IC te chnology. (C) 2000 Elsevier Science Ltd. All rights reserved.