Long Wavelength Roughness Optimization during Thin Cu Film Electropolish
| Autor: | Anne E. Miller, Tatyana N. Andryushchenko, Fischer Paul B |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Materials science
business.industry General Chemical Engineering Analytical chemistry Surface finish Diffusion layer Root mean square Electropolishing Overburden Optics Chemical-mechanical planarization Electrochemistry Surface roughness General Materials Science Wafer Electrical and Electronic Engineering Physical and Theoretical Chemistry business |
| Zdroj: | Electrochemical and Solid-State Letters. 9:C181 |
| ISSN: | 1099-0062 |
| DOI: | 10.1149/1.2344828 |
| Popis: | Recent studies of Cu electropolish indicate planarization is not possible due to a large diffusion layer thickness relative to a small post-electroplate step height and small Cu overburden available for electropolish. Assuming an integration scheme that includes a CMP step followed by electropolish, the subsequent challenge of maintaining surface roughness over 300 μm range while electropolishing thin Cu films is addressed by optimizing applied current. For a typical electropolish solution of 6.4 M H 3 PO 4 , 5.4 M glycerin and 17.5 M H 2 O, an rms value of 38 A, comparable to the incoming post-CMP wafers, is demonstrated for 2500 A Cu removal. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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