Surface modification by subsurface pressure induced diffusion

Journal Article · Mon Jan 23 00:00:00 EST 2012 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3679616· OSTI ID:22025414

Zimmermann, Claus G ^[1]

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1. EADS Astrium, 81663 Munich (Germany)

Polycrystalline Ag, covered with a nm thin siloxane layer, was irradiated with ultraviolet light in vacuum at 500 K. Ag particles of different aspect ratios, 50-1000 nm in size, formed on the surface, including a small fraction of nanorods. Pressurized water vapor bubbles are created in the subsurface region by hydrogen radicals photo-chemically released by the siloxane layer. They provide the driving force for a diffusive material flux along grain boundaries to the surface. This mechanism was modeled and found to agree with the experimental timescale: approximately 300 h are required for a 1000 nm particle to form.

• OSTI ID: 22025414
• Journal Information: Applied Physics Letters, Vol. 100, Issue 4; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ASPECT RATIO
DIFFUSION
GRAIN BOUNDARIES
HYDROGEN
LAYERS
MODIFICATIONS
NANOSTRUCTURES
ORGANIC COMPOUNDS
PARTICLE SIZE
PARTICLES
PHOTOCHEMISTRY
POLYCRYSTALS
RADICALS
SILVER
SURFACE TREATMENTS
SURFACES
ULTRAVIOLET RADIATION
VISIBLE RADIATION
WATER VAPOR