Control of Tungsten Protrusion with Surface Active Agent during Tungsten Chemical Mechanical Polishing. (29th November 2017)

• Record Type: Journal Article
• Authors: You, Keungtae; Seo, Jihoon; Kim, Patrick Joo Hyun; Song, Taeseup
• Is Part Of: ECS journal of solid state science and technology. Volume 6:Number 12(2017)
• Page Start: P822
• Page End: P827
• Publication Date: 2017-11-29
• Subjects: Chemical Mechanical Polishing -- CTAB -- Tungsten; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2.0151712jss
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : With shrinkage of the minimum feature size to sub-14 nm, protrusion/dishing issues in chemical mechanical planarization (CMP) processes have become increasingly important to address. In this study, we propose an advanced slurry formulation with a surface active agent to prevent W protrusion during the W CMP process. In the presence of surface active agent, blanket removal rates on both W and SiO2 films showed non-Prestonian behavior at a low threshold pressure, which is explained by adsorption characteristics of the surface active agent on the films. To study the effect of the surface active agent on W protrusion, W-patterned wafers were polished at the threshold pressure. As the concentration of the surface active agent increased from 0 to 12 mM, W protrusion from patterns with line/space widths of 0.5 μm/0.5 μm decreased significantly from 186 to 30 Å. The mechanism on the significant decrease in W protrusion behavior in the presence of the surface active agent is discussed.