Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers

Satake, Makoto; Yamada, Masaki; Li, Hu; Karahashi, Kazuhiro; Hamaguchi, Satoshi

doi:https://doi.org/10.1116/1.4930242

Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers

Satake, Makoto; Yamada, Masaki; Li, Hu et al.

Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics, 2015, 33(5), 051810

Number of Access:444（2025-08-14 16:33 Counts）

Identifier to cite or link to this item: https://hdl.handle.net/11094/78463

Link to primary information

File	Format	Terms of use	Size	Views	Date.Available	Description	information
JVacSciTechnolB_33_05_051810	pdf	None	1.85 MB	320	2021.02.05

Item Information

Output File Export EndNote Basic Export Mendeley

Title	Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers
Creator	CreatorName Satake, Makoto
	CreatorName Yamada, Masaki
	CreatorName Li, Hu
	NRID 1000060451118 1000060451118 ORCID 0000-0001-9951-6573 0000-0001-9951-6573 researchmap permalink karahashi karahashi Scopus Author ID 6602275601 6602275601 CreatorName Karahashi, Kazuhiro
	NRID 1000060301826 1000060301826 ORCID 0000-0001-6580-8797 0000-0001-6580-8797 researchmap permalink satoshi_hamaguchi satoshi_hamaguchi Scopus Author ID 55220082400 55220082400 CreatorName Hamaguchi, Satoshi
Description	M. Satake et al., Journal of Vacuum Science & Technology B 33, 051810 (2015) https://doi.org/10.1116/1.4930242
Abstract	Mechanisms of dry etching resistance of Ta masks, which are widely used for magnetic random access memory etching processes, have been investigated for a better understanding of their faceting characteristics. In magnetic-material etching processes by CO/NH3 or CH3OH plasmas, CO+ ion is considered as one of the most dominant ion species irradiating the substrate surface. An earlier study by Li et al. [J. Vac. Sci. Technol. A 33, 040602 (2015)] has shown that the Ta sputtering yield by CO+ ion irradiation depends strongly on the ion irradiation angle and the level of the surface oxidation. In this study, the primary focus is placed on the effects of surface oxidation and physical sputtering only (without possible chemical effects of carbon) on the etching rate of Ta, and the etching characteristics of Ta and Ta2O5 have been examined with Ar+ and/or oxygen ion beams. It has been found that there is a strong negative correlation between the etching rate of Ta and the oxidation states of the surface oxide layer formed during the etching process; the higher the oxidation states are, the lower the etching rate becomes. The results indicate that a strong propensity of a Ta mask to taper by irradiation of oxidizing ions (i.e., strong ion-irradiation-angle dependence of the Ta etching rate) arises from less efficient oxidation of a tapered surface by incident oxidizing ions, which enter the surface with an oblique angle.
Publisher	American Institute of Physics
Source Title	Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics
Volume (Issue)	33(5)
Page	051810
Date of Issued	2015-09
Language	English
Handle URL	https://hdl.handle.net/11094/78463
PISSN	21662746
eISSN	21662754
NCID	AA10804928
Relation.isIdenticalTo	DOI (Publisher Version) https://doi.org/10.1116/1.4930242
Access Rights	open access
CopyRight	This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Journal of Vacuum Science & Technology B 33, 051810 (2015) and may be found at https://doi.org/10.1116/1.4930242.
oaire:version	Version of Record
Category	学術雑誌論文 Journal Article

Resource Type	journal article
Local Type	Journal Article
DCTERMS.bibliographicCitation	Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics. 2015, 33(5), p. 051810
DC.title	Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers
DC.creator	Satake, Makoto
	Yamada, Masaki
	Li, Hu
	Karahashi, Kazuhiro
	Hamaguchi, Satoshi
DC.publisher	American Institute of Physics
DC.language' scheme='DCTERMS.RFC1766	English
DCTERMS.issued' scheme='DCTERMS.W3CDTF	2015-09
DC.identifier	https://doi.org/10.1116/1.4930242
DC.description	M. Satake et al., Journal of Vacuum Science & Technology B 33, 051810 (2015) https://doi.org/10.1116/1.4930242
DCTERMS.abstract	Mechanisms of dry etching resistance of Ta masks, which are widely used for magnetic random access memory etching processes, have been investigated for a better understanding of their faceting characteristics. In magnetic-material etching processes by CO/NH3 or CH3OH plasmas, CO+ ion is considered as one of the most dominant ion species irradiating the substrate surface. An earlier study by Li et al. [J. Vac. Sci. Technol. A 33, 040602 (2015)] has shown that the Ta sputtering yield by CO+ ion irradiation depends strongly on the ion irradiation angle and the level of the surface oxidation. In this study, the primary focus is placed on the effects of surface oxidation and physical sputtering only (without possible chemical effects of carbon) on the etching rate of Ta, and the etching characteristics of Ta and Ta2O5 have been examined with Ar+ and/or oxygen ion beams. It has been found that there is a strong negative correlation between the etching rate of Ta and the oxidation states of the surface oxide layer formed during the etching process; the higher the oxidation states are, the lower the etching rate becomes. The results indicate that a strong propensity of a Ta mask to taper by irradiation of oxidizing ions (i.e., strong ion-irradiation-angle dependence of the Ta etching rate) arises from less efficient oxidation of a tapered surface by incident oxidizing ions, which enter the surface with an oblique angle.
DC.rights	This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Journal of Vacuum Science & Technology B 33, 051810 (2015) and may be found at https://doi.org/10.1116/1.4930242.
DC.format	78463
citation_title	Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers
citation_author	Satake, Makoto
	Yamada, Masaki
	Li, Hu
	Karahashi, Kazuhiro
	Hamaguchi, Satoshi
citation_publisher	American Institute of Physics
citation_language	English
citation_date	2015-09
citation_journal_title	Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics
citation_volume	33
citation_issue	5
citation_firstpage	051810
citation_doi	https://doi.org/10.1116/1.4930242
citation_public_url	https://hdl.handle.net/11094/78463

Correlation between dry etching resistance of Ta masks and the oxidation states of the surface oxide layers

Link to primary information

Item Information

Show details