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Nanometer-thick conformal pore sealing of self-assembled mesoporous silica by plasma-assisted atomic layer deposition.

ABSTRACT: On a porous substrate, regular atomic layer deposition (ALD) not only takes place on top of the substrate but also penetrates into the internal porosity. Here we report a plasma-assisted process in which the ALD precursors are chosen to be nonreactive unless triggered by plasma, so that ALD can be spatially defined by the supply of plasma irradiation. Since plasma cannot penetrate within the internal porosity, ALD has been successfully confined to the immediate surface. This not only gives a possible solution for sealing of porous low dielectric constant films with a conformal layer of nm-scale thickness but also enables us to progressively reduce the pore size of mesoporous materials in a sub-A/cycle fashion for membrane formation.

SUBMITTER: Jiang YB

PROVIDER: S-EPMC2707262 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Nanometer-thick conformal pore sealing of self-assembled mesoporous silica by plasma-assisted atomic layer deposition.

Jiang Ying-Bing YB Liu Nanguo N Gerung Henry H Cecchi Joseph L JL Brinker C Jeffrey CJ

Journal of the American Chemical Society 20060801 34

On a porous substrate, regular atomic layer deposition (ALD) not only takes place on top of the substrate but also penetrates into the internal porosity. Here we report a plasma-assisted process in which the ALD precursors are chosen to be nonreactive unless triggered by plasma, so that ALD can be spatially defined by the supply of plasma irradiation. Since plasma cannot penetrate within the internal porosity, ALD has been successfully confined to the immediate surface. This not only gives a pos ...[more]

PMID: 16925407

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