Comparison of novel cleaning solutions with various chelating agents for post-CMP cleaning on poly-Si film

Author

Pan, Tung Ming ; Lei, Tan Fu ; Ko, Fu Hsiang ; Chao, Tien Sheng ; Chiu, Tzu Huan ; Lee, Ying Hao ; Lu, Chih Peng

Author_Institution

Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

14

Issue

4

fYear

2001

fDate

11/1/2001 12:00:00 AM

Firstpage

365

Lastpage

371

Abstract

In this study, various cleaning solutions containing chelating agents with carboxyl acid group (-COOH), such as ethylenediaminetetraacetic acid, citric acid and oxalic acid, were developed for post-poly-Si CMP cleaning. The chelating agent and tetramethylammonium hydroxide (TMAH) were simultaneously added into 2% ammonium hydroxide alkaline solution to promote the removal efficiency on particles and metallic impurities. The effectiveness of various cleaning recipes and their interaction mechanism with the poly-Si surface were studied. We could explain the surface behavior of various cleaning solutions by the different molecular size and charge of chelating agents. Based on the mechanism, the behavior of surface particle and metallic impurity can be realized. The co-existence of TMAH with citric acid or oxalic acid in the alkaline cleaning solutions can significantly enhance the electrical properties of capacitors

Keywords

chemical mechanical polishing; elemental semiconductors; impurities; integrated circuit manufacture; rough surfaces; semiconductor technology; semiconductor thin films; silicon; substrates; surface cleaning; NH₄OH; NH₄OH alkaline solution; Si; alkaline cleaning solutions; carboxyl acid group; chelating agents; citric acid; cleaning recipes; cleaning solutions comparison; ethylenediaminetetraacetic acid; metallic impurities; molecular size; oxalic acid; particle removal; poly-Si surface; polysilicon film; post-CMP cleaning; removal efficiency; surface behavior; tetramethylammonium hydroxide; Chaos; Chemicals; Cleaning; EPROM; Impurities; Planarization; Rough surfaces; Slurries; Surface contamination; Surface roughness;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.964323

Filename

964323