Surface cleaning method for elimination of Cu-oxide layer formed on Cu film

Author

Ju, Hyun-jin ; Lee, Yong-Hyuk ; Nho, Sang-Soo ; Choi, Eun-Hey ; Rha, Sa-Kyun ; Lee, Youn-Seoung

Author_Institution

Dept. of Mater. Eng., Hanbat Nat. Univ., Daejeon, South Korea

fYear

2011

fDate

4-7 July 2011

Firstpage

1

Lastpage

5

Abstract

We investigated the effects of surface cleaning to eliminate the surface native oxide on Cu film. The Cu seed layer was deposited on Ti/p-Si (100) by sputter deposition. NH₄OH and H₂SO₄ solutions after TS-40A pretreatment were used to remove the Cu-oxide, and then the changed surface of Cu film was estimated by AFM, SEM, and XPS. By H₂SO₄ treatment after TS-40A pretreatment, the Cu-oxides on surface of Cu seed film [including CuO, Cu(OH)₂, and CuCO₃ contaminants] were eliminated uniformly. However, by NH₄OH treatment after TS-40A pretreatment numerous large and small etch pits formed and the RMS roughness of Cu film surface was larger. Consequently, we found that H₂SO₄ cleaning after TS-40A pretreatment is very effective at Cu-oxide removal.

Keywords

X-ray photoelectron spectra; atomic force microscopy; copper; integrated circuit metallisation; metallic thin films; scanning electron microscopy; sputtered coatings; surface cleaning; surface roughness; AFM; Cu; RMS roughness; SEM; Si; Ti-Si; XPS; copper film surface; p-Si (100); sputter deposition; surface cleaning; surface native oxide; Copper; Films; Surface cleaning; Surface morphology; Surface roughness;

fLanguage

English

Publisher

ieee

Conference_Titel

Physical and Failure Analysis of Integrated Circuits (IPFA), 2011 18th IEEE International Symposium on the

Conference_Location

Incheon

ISSN

1946-1542

Print_ISBN

978-1-4577-0159-7

Electronic_ISBN

1946-1542

Type

conf

DOI

10.1109/IPFA.2011.5992766

Filename

5992766