Defect reduction in Cu chemical-mechanical polishing

The chemical-mechanical polishing (CMP) of Cu is a critical step in the manufacture of ultra-large-scale integrated (ULSl) semiconductor devices. During this process, undesirable scratches are formed on the surface being polished [I -3]. Recent research suggests that the "killer" scratches...

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Bibliographic Details
Main Authors: Eusner, Thor, Saka, Nannaji, Chun, Jung-Hoon
Other Authors: Massachusetts Institute of Technology. Laboratory for Manufacturing and Productivity
Format: Article
Language:en_US
Published: Institute of Electrical and Electronics Engineers 2013
Online Access:http://hdl.handle.net/1721.1/78335
https://orcid.org/0000-0002-8480-5572
https://orcid.org/0000-0003-1607-3581
Description
Summary:The chemical-mechanical polishing (CMP) of Cu is a critical step in the manufacture of ultra-large-scale integrated (ULSl) semiconductor devices. During this process, undesirable scratches are formed on the surface being polished [I -3]. Recent research suggests that the "killer" scratches found on the Cu wafers are due to the soft pad asperities and not necessarily by the hard abrasives in the slurry [4,5]. Figure 1 shows examples of scratches on a Cu coating due to pad asperities. This paper presents the theory and experimental validation of scratching by soft pad asperities in Cu CMP. Based on the models and experimental results, practical solutions for mitigating scratching by pad asperities in Cu CMP are suggested.