Via hole-related simultaneous stress-induced extrusion and void formation in Al interconnects

Author

Shibata, Hajime ; Matsuno, T. ; Hashimoto, K.

Author_Institution

Toshiba Corp., Kawasaki, Japan

fYear

1993

Firstpage

340

Lastpage

344

Abstract

A reliability issue caused by high temperature annealing after via hole opening is investigated. A high temperature anneal above 450 degrees C causes simultaneous Al extrusion at the via hole interface and void formation in Al interconnects, drastically degrading the reliability of Al lines with vias. Based on in situ observation of extrusion/void formation and two-dimensional elastic deformation analysis, it was found that this phenomenon is due to the movement of Al atoms towards the via hole interface resulting from the thermal expansion and the stress gradient formed in the Al line near the via hole during the anneal sequence. Experimental results and the influence of such an anneal process on the reliability of Al lines are discussed.<>

Keywords

aluminium; annealing; circuit reliability; elastic deformation; metallisation; thermal expansion; 450 degC; Al extrusion; Al interconnects; high temperature annealing; reliability; stress gradient; stress-induced extrusion; thermal expansion; two-dimensional elastic deformation analysis; via hole interface; via hole opening; void formation; Impurities; Plasma applications; Plasma temperature; Plugs; Rapid thermal annealing; Surface topography; Surface treatment; Thermal stresses; Tin; Ultra large scale integration;

fLanguage

English

Publisher

ieee

Conference_Titel

Reliability Physics Symposium, 1993. 31st Annual Proceedings., International

Conference_Location

Atlanta, GA, USA

Print_ISBN

0-7803-0782-8

Type

conf

DOI

10.1109/RELPHY.1993.283278

Filename

283278