Early Increase in Resistance during Electromigration in AlCu-plugged Via Structures.

DOI Web Site Web Site Web Site 11 References
  • Hoshino Kazuhiro
    Semiconductor Company, Sony Corporation, 4-14-1, Asahi-cho, Atsugi, Kanagawa 243-0014, Japan

Bibliographic Information

Other Title
  • Early Increase in Resistance during Electlomigration in AlCu-plugged Via Structures

Search this article

Abstract

This paper reports on the electromigration (EM) failure mechanism in AlCu-plugged via holes. Based on an observed increase in the via chain resistance and cross-sectional analysis of the damaged vias, an early failure and a normal failure were identified during the EM tests. The early failure occurred in the Al plug at the cathode side, and was attributed to void growth in the Al plugs during EM. The normal failure occurred not in the Al plugs, but on the Al lines, and exhibited a three-stage increase in resistance. An early increase in resistance of about 5% was found in the normal failure during EM. Failure sites were observed around the terminated via using the optical-beam-induced resistance change (OBIRCH) method. At the failure sites, crystallization of CuAl2 was observed at the anode via using transmission electron microscope (TEM). The early increase in resistance caused by CuAl2 crystal formation at the anode was brought about by using the AlCu via plug. This resistance increase is a serious problem for the small AlCu via connected to long or wide AlCu interconnects.

Journal

References(11)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top