Mechanism of stress-induced migration in VLSI aluminum metallization

Author

Hinode, Kenji ; Asano, Isamu ; Homma, Yoshio

Author_Institution

Hitachi Ltd., Tokyo, Japan

fYear

1988

fDate

13-14 June 1988

Firstpage

429

Lastpage

435

Abstract

Void formation in aluminum lines caused by high-temperature heat treatment is investigated in connection with passivation stress. Passivation layers bulge due to their own compressive stress, forcing the aluminum they encapsulate to expand. When the temperature is high enough, the aluminum moves, forming voids. This process is comparable to that caused by thermal expansion mismatch. This mechanism is considered to explain the dependence of the observed phenomenon on treatment temperatures, cooling rate, line width, passivation type, and passivation thickness.<>

Keywords

VLSI; aluminium; diffusion in solids; heat treatment; metallisation; passivation; stress analysis; voids (solid); Al; VLSI metallisation; compressive stress; cooling rate; high-temperature heat treatment; line width; passivation stress; stress-induced migration; temperature dependence; thermal expansion mismatch; void formation; Aluminum; Compressive stress; Conductors; Heat treatment; Metallization; Passivation; Plasma temperature; Thermal expansion; Thermal stresses; Very large scale integration;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Multilevel Interconnection Conference, 1988. Proceedings., Fifth International IEEE

Conference_Location

Santa Clara, CA, USA

Type

conf

DOI

10.1109/VMIC.1988.14222

Filename

14222