Intermetallic compound formation in hot aluminum metallization and its effect on etching and electromigration

Lianjun Liu; Dong Lu; Pang Dow Foo; Way Tat Tan; Kurt Kowk; Gang Zou; Man Siu Tse

doi:10.1117/12.250882

13 September 1996 Intermetallic compound formation in hot aluminum metallization and its effect on etching and electromigration

Lianjun Liu, Dong Lu, Pang Dow Foo, Way Tat Tan, Kurt Kowk, Gang Zou, Man Siu Tse

Author Affiliations +

Proceedings Volume 2875, Microelectronic Device and Multilevel Interconnection Technology II; (1996) https://doi.org/10.1117/12.250882
Event: Microelectronic Manufacturing 1996, 1996, Austin, TX, United States

Abstract

Application of hot aluminum (or aluminum plug) in deep submicron VLSI metallization has attracted much attention. Studies have shown that introduction of a titanium wetting layer prior to aluminum deposition improves the capability to fill deep submicron contacts/vias with vertical sidewalls in hot aluminum process. In this paper, we report that the introduction of this titanium wetting layer can also greatly improve the aluminum etching process window. Transmission Electron Microscope (TEM) analysis indicates that a continuous layer of TiAl₃ intermetallic compound has formed at the AlSi(1%)Cu(0.5%)/Ti interface during hot aluminum deposition. In the case of without titanium wetting layer, TiAl₃ compound can also form at AlSiCu/TiN interface but it is not a continuous layer. The formation of the continuous TiAl₃ layer is believed to be responsible for the improvement of etching process window. Electromigration lifetime test is also performed on samples with and without titanium wetting layer. While results show that the introduction of titanium wetting layer increases the electromigration lifetime of the hot aluminum metallization, too much TiAl₃ formation may degrade the electromigration performance due to its higher resistivity.

Citation Download Citation

Lianjun Liu, Dong Lu, Pang Dow Foo, Way Tat Tan, Kurt Kowk, Gang Zou, and Man Siu Tse "Intermetallic compound formation in hot aluminum metallization and its effect on etching and electromigration", Proc. SPIE 2875, Microelectronic Device and Multilevel Interconnection Technology II, (13 September 1996); https://doi.org/10.1117/12.250882

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available