New CMP processes development and challenges for 7nm and beyond

Huang, Haigou; Koli, Dinesh; Zhang, Junyi; Tsai, Stan; Chao, Taifong; Lu, Yuanfang; Kim, Hee Jin; Fang, Qiang; Lu, Wenyin

doi:10.1109/cstic.2018.8369258

Cited by 4 publications

(1 citation statement)

References 5 publications

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“…CMP slurries have been utilized in processes to planarize structures which consist of several different materials. Chemical reagents in the CMP slurry react with the wafer surface being polished, forming a chemically modified top layer with desirable properties compared to the initial wafer surface [10][11]. The selectivity to different films in CMP is commonly determined by the type of slurry and depends on the addition of pH regulators, oxidizers, or stabilizers [12][13].…”

Section: Introductionmentioning

confidence: 99%

Enhancement of Selectivity for Chemical Mechanical Polishing by Ultra-High-Dose C and Si Ion Implantation

Yuan,

Omori,

Yamaguchi

et al. 2024

IEEE J. Electron Devices Soc.

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The selectivity of chemical mechanical polishing (CMP) is successfully enhanced due to the modification of the film surface by ultra-high-dose ion implantation for the first time. The removal rate (RR) of CMP for SiO2 and Si3N4 films was changed by implanted ions. On the other hand, polycrystalline silicon (poly-Si) films had no change regardless of ion implantation. When C + is implanted at 3×10 16 ions/cm 2 into SiO2, the RR decreases by about 40% compared with that without implantation. However, no significant change was observed after the implantation of C + at 1×10 16 ions/cm 2 or Si + to SiO2 and poly-Si films. New findings about CMP mechanism that are against Borst's Langmuir-Hinshelwood model have been made when the film is modified by using high-dose implantation.

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Section: Introductionmentioning

confidence: 99%

Enhancement of Selectivity for Chemical Mechanical Polishing by Ultra-High-Dose C and Si Ion Implantation

Yuan,

Omori,

Yamaguchi

et al. 2024

IEEE J. Electron Devices Soc.

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Super fine cerium hydroxide abrasives for SiO2 film chemical mechanical planarization performing scratch free

Son

Jeong

Kim

et al. 2021

Sci Rep

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Face-centered-cubic crystallized super-fine (~ 2 nm in size) wet-ceria-abrasives are synthesized using a novel wet precipitation process that comprises a Ce4+ precursor, C3H4N2 catalyst, and NaOH titrant for a synthesized termination process at temperature of at temperature of 25 °C. This process overcomes the limitations of chemical–mechanical-planarization (CMP)-induced scratches from conventional dry ceria abrasives with irregular surfaces or wet ceria abrasives with crystalline facets in nanoscale semiconductor devices. The chemical composition of super-fine wet ceria abrasives depends on the synthesis termination pH, that is, Ce(OH)4 abrasives at a pH of 4.0–5.0 and a mixture of CeO2 and Ce(OH)4 abrasives at a pH of 5.5–6.5. The Ce(OH)4 abrasives demonstrate better abrasive stability in the SiO2-film CMP slurry than the CeO2 abrasives and produce a minimum abrasive zeta potential (~ 12 mV) and a minimum secondary abrasive size (~ 130 nm) at the synthesis termination pH of 5.0. Additionally, the abrasive stability of the SiO2-film CMP slurry that includes super-fine wet ceria abrasives is notably sensitive to the CMP slurry pH; the best abrasive stability (i.e., a minimum secondary abrasive size of ~ 130 nm) is observed at a specific pH (6.0). As a result, a maximum SiO2-film polishing rate (~ 524 nm/min) is achieved at pH 6.0, and the surface is free of stick-and-slip type scratches.

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