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Enhanced crystallinity of epitaxial graphene grown on hexagonal SiC surface with molybdenum plate capping.

ABSTRACT: The crystallinity of epitaxial graphene (EG) grown on a Hexagonal-SiC substrate is found to be enhanced greatly by capping the substrate with a molybdenum plate (Mo-plate) during vacuum annealing. The crystallinity enhancement of EG layer grown with Mo-plate capping is confirmed by the significant change of measured Raman spectra, compared to the spectra for no capping. Mo-plate capping is considered to induce heat accumulation on SiC surface by thermal radiation mirroring and raise Si partial pressure near surface by confining the sublimated Si atoms between SiC substrate and Mo-plate, which would be the essential contributors of crystallinity enhancement.

SUBMITTER: Jin HB

PROVIDER: S-EPMC5386107 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Enhanced crystallinity of epitaxial graphene grown on hexagonal SiC surface with molybdenum plate capping.

Jin Han Byul HB Jeon Youngeun Y Jung Sungchul S Modepalli Vijayakumar V Kang Hyun Suk HS Lee Byung Cheol BC Ko Jae-Hyeon JH Shin Hyung-Joon HJ Yoo Jung-Woo JW Kim Sung Youb SY Kwon Soon-Yong SY Eom Daejin D Park Kibog K

Scientific reports 20150424

The crystallinity of epitaxial graphene (EG) grown on a Hexagonal-SiC substrate is found to be enhanced greatly by capping the substrate with a molybdenum plate (Mo-plate) during vacuum annealing. The crystallinity enhancement of EG layer grown with Mo-plate capping is confirmed by the significant change of measured Raman spectra, compared to the spectra for no capping. Mo-plate capping is considered to induce heat accumulation on SiC surface by thermal radiation mirroring and raise Si partial p ...[more]

PMID: 25905989

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