A new failure mechanism by corrosion of tungsten in a tungsten plug process

Author

Bothra, S. ; Sur, H. ; Liang, V.

Author_Institution

VLSI Technol. Inc., San Jose, CA, USA

fYear

1998

fDate

March 31 1998-April 2 1998

Firstpage

150

Lastpage

156

Abstract

The tungsten filled via plug process is commonly used in sub-half micron CMOS process technologies. As process technologies shrink beyond the 0.25 /spl mu/m generation, the metal overlap over the via also reduces. This results in vias which are not fully covered by the overlying interconnect lines. In the evaluation of such structures, we have observed a new failure mechanism resulting in completely unfilled vias due to electrochemical corrosion accelerated by a positive charge on specific structures.

Keywords

CMOS integrated circuits; corrosion; electrochemistry; failure analysis; integrated circuit interconnections; integrated circuit metallisation; integrated circuit testing; integrated circuit yield; tungsten; 0.25 micron; CMOS process technology; W; accelerated electrochemical corrosion; corrosion; failure mechanism; interconnect lines; positive charge corrosion acceleration; tungsten filled via plug process; tungsten plug process; unfilled vias; via coverage; via metal overlap; Bonding; CMOS process; CMOS technology; Circuit testing; Corrosion; Electrical resistance measurement; Failure analysis; Plugs; Tungsten; Very large scale integration;

fLanguage

English

Publisher

ieee

Conference_Titel

Reliability Physics Symposium Proceedings, 1998. 36th Annual. 1998 IEEE International

Conference_Location

Reno, NV, USA

Print_ISBN

0-7803-4400-6

Type

conf

DOI

10.1109/RELPHY.1998.670473

Filename

670473