Void formation in a TiW/AlSiCu metallisation scheme

Author

van Houtum, H.J.W. ; Tibbe, J. ; Dirks, A.G.

Author_Institution

Philips Semicond., Nijmegen, Netherlands

fYear

1991

fDate

11-12 Jun 1991

Firstpage

235

Lastpage

241

Abstract

The voiding behaviour of AlSiCu is described in an TiW/AlSiCu metallization scheme for submicron technology. A direct correlation was found between waiting time between TiW and AlSiCu deposition and voiding. Direct transfer of wafers between the two metal deposition systems enhances voiding. Analysis of the TiW/AlSiCu bilayer with several interface conditions revealed a rather clear correlation to voiding: Interaction between AlSiCu and TiW. It is proposed that the TiW-Al(SiCu) interaction enhances voiding in the AlSiCu interconnection due to formation of intermetallic phases at the Al grain boundaries. Volume effects of intermetallic phase formation enhances local strain at the Al grain boundaries and may initiate void formation

Keywords

VLSI; aluminium alloys; copper alloys; metallisation; reliability; silicon alloys; titanium alloys; tungsten alloys; Al grain boundaries; AlSiCu alloy metallisation; TiW alloy films; TiW-AlSiCu; VLSI; exposure to air; formation of intermetallic phases; interface conditions; local strain; multilevel interconnection; reliability issues; voiding behaviour; waiting time; Electrons; Grain boundaries; Intermetallic; Metallization; Passivation; Plasma measurements; Sputter etching; Sputtering; Surface cleaning; Thermal stresses;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Multilevel Interconnection Conference, 1991, Proceedings., Eighth International IEEE

Conference_Location

Santa Clara, CA

Print_ISBN

0-87942-673-X

Type

conf

DOI

10.1109/VMIC.1991.152993

Filename

152993