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

In order to enhance the reliability of silicon ICs, an electrochemical anodizing technique was used to form an intralevel alumina insulator for multilevel aluminum metallization. The low dielectric constant of about 2.4 was attained by chemical etching of porous alumina films in an anodizing solution. The intralevel insulator based on porous alumina had the following parameters measured: the breakdown voltage was more than 400 V, the leakage current 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 the developed structure offers advantages over aluminum interconnection passivated by silica insulator. The reliability of built in aluminum interconnection with low-E porous alumina satisfies all requirements of advanced IC technology. (C) 2000 Elsevier Science Ltd. All rights reserved.