Chemical and electrical passivation of single-crystal silicon(100) surfaces Through a two-step chlorination/alkylation process

E. Joseph Nemanick, Patrick T. Hurley, Lauren J. Webb, David W. Knapp, David J. Michalak, Bruce S. Brunschwig, Nathan S Lewis

Research output: Contribution to journalArticle

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Abstract

Single-crystal Si(100) surfaces have been functionalized by using a two-step radical chlorination-Grignard (R = MgCl, R = CH3, C 2H5, C4H9, C6H 5, or CH2C6H5) alkylation method. After alkylation, no chlorine was detectable on the surface by X-ray photoelectron spectroscopy (XPS), and the C 1 s region showed a silicon-induced peak shift indicative of a Si-C bond. The relative intensity of this peak decreased, as expected, as the steric bulk of the alkyl increased. Despite the lack of full alkyl termination of the atop sites of the Si(100) surface, functionalization significantly reduced the rate of surface oxidation in air compared to that of the H-terminated Si(100) surface, with alkylated surfaces forming less than half a monolayer of oxide after over one month of exposure to air. Studies of the charge-carrier lifetime with rf photoconductivity decay methods indicated a surface recombination velocity of -1 for methylated surfaces, and -1 for Si surfaces functionalized with the other alkyl groups evaluated. Soft X-ray photoelectron spectroscopic data indicated that the H-Si(100) surfaces were terminated by SiH, SiH2, and SiH3 species, whereas Cl-Si(100) surfaces were predominantly terminated by monochloro (SiCl and SiHCl) and dichloro (SiCl 2 and SiHCl2) Si species. Methylation produced signals consistent with termination by Si-alkyl bonding arising from SiH-(CH 3)-, SiH2(CH3)-, and Si(CH3) 2-type species.

Original languageEnglish
Pages (from-to)14770-14778
Number of pages9
JournalJournal of Physical Chemistry B
Volume110
Issue number30
DOIs
Publication statusPublished - Aug 3 2006

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chlorination
Chlorination
alkylation
Alkylation
Silicon
Passivation
passivity
Single crystals
single crystals
silicon
methylidyne
methylation
Methylation
Carrier lifetime
Chlorine
air
Photoconductivity
carrier lifetime
Photoelectrons
Air

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Chemical and electrical passivation of single-crystal silicon(100) surfaces Through a two-step chlorination/alkylation process. / Nemanick, E. Joseph; Hurley, Patrick T.; Webb, Lauren J.; Knapp, David W.; Michalak, David J.; Brunschwig, Bruce S.; Lewis, Nathan S.

In: Journal of Physical Chemistry B, Vol. 110, No. 30, 03.08.2006, p. 14770-14778.

Research output: Contribution to journalArticle

Nemanick, E. Joseph ; Hurley, Patrick T. ; Webb, Lauren J. ; Knapp, David W. ; Michalak, David J. ; Brunschwig, Bruce S. ; Lewis, Nathan S. / Chemical and electrical passivation of single-crystal silicon(100) surfaces Through a two-step chlorination/alkylation process. In: Journal of Physical Chemistry B. 2006 ; Vol. 110, No. 30. pp. 14770-14778.
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AU - Lewis, Nathan S

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