This letter considers field emission from self-assembled silicon nanostructure arrays fabricated on n- and p-type silicon (100) substrates using electron beam rapid thermal annealing. Arrays of nanostructures with an average height of 8 nm were formed by substrate annealing at 1100 °C for 15 s. Following conditioning, the Si nanostructure field emission characteristics become stable and reproducible with Fowler–Nordheim tunneling occurring for fields as low as 2Vμm−1. At higher fields, current saturation effects are observed for both n-type and p-type samples. These studies suggest that the mechanism influencing current saturation at high fields acts independently of substrate conduction type.

Effect of crystal orientation on self-assembled silicon nanostructures formed by electron-beam annealing J. Appl. Phys. 97, 094301 (2005); 10.1063/1.1877819Incorporation of manganese into semiconducting ScN using radio frequency molecular beam epitaxy A technique for the rapid, uncomplicated and lithography free fabrication of silicon nanostructures on both n-type and p-type Si͑100͒ substrates is presented. The nanofabrication method employs electron beam rapid thermal annealing of Si͑100͒ substrates which have undergone no prior processing and thus still contain the native oxide. The resulting nanostructures are distributed across the entire Si surface and are square based and aligned to the ͓110͔ direction. Nanostructure growth was only observed in the temperature range 800-1200°C and has been shown to occur following annealing durations as short as 3 s. Nanopillars over 20 nm high have been fabricated following annealing for 120 s. The initial stage of nanostructure growth involves thermal decomposition of the native oxide resulting in atomic scale disorder of the Si surface. Following complete oxide desorption, diffusive Si species migrate across the surface in response to diffusion barriers established on the strained potential-energy surface, nucleating islands at kinetically favored sites. With continued annealing the island number and size evolves according to crystal ripening processes. Enhancement of the oxide desorption and crystal growth rates due to electron irradiation are discussed.

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SiC-surface nanostructures on silicon were produced by 10keV carbon ion implantation into silicon followed by annealing to 1000°C for 15s under high-vacuum conditions using a raster-scanned electron beam. Following implantation, an amorphous layer is produced which starts at the surface and extends 65nm into the substrate. Following annealing, the implanted surface layer remains amorphous but becomes covered with semi-spherical crystalline features up to 300nm in diameter. The nanocrystals have been confirmed to be SiC which, following nucleation, grow as a result of C and Si diffusion across the oxide free substrate surface during annealing.

The tracer diffusion of hydrogen is studied in amorphous Si 3 N 4 :H films which were produced by rf magnetron reactive sputtering. The diffusion experiments were carried out in the temperature range between 700 and 1000 • C with ion implanted deuterium isotopes. Secondary ion mass spectrometry was used for depth profile analysis. While a considerable part of the tracer is immobilized due to the interaction with the implantation damage, the other part migrates freely into the film, wherefrom diffusivities are extracted. These diffusivities coincide with those obtained from a control experiment with a gas exchange technique, demonstrating that the implantation damage has no significant influence on the determination of the correct diffusivities themselves. 2 H transport can be described by the concept of trap limited diffusion, where the tracer atoms are temporarily trapped by intrinsic film defects, presumably nitrogen dangling bonds. For the present case of a considerably high dissociation rate of trapped hydrogen, effective diffusivities are derived which obey an Arrhenius behaviour with a large activation energy of E = 3.4 eV and a pre-exponential factor of D 0 = 5 × 10 −4 m 2 s −1 . The effect on diffusion of pre-annealing the films prior to diffusion in nitrogen and possible structural rearrangements involved, as well as of charging the films with hydrogen up to 2.6 at.%, is analysed.

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This paper discusses the growth of silicon nanostructures on silicon (100), (110), and (111) substrates by electron-beam annealing. The nanofabrication procedure involves annealing of the untreated Si substrates at 1100°C for 15s using a raster scanned 20-keV electron beam. Nanostructuring occurs as a result of kinetic amplification of the surface disorder induced by thermal decomposition of the native oxide. Pyramidal and truncated pyramidal nanocrystals were observed on Si(100) surfaces. The nanostructures are randomly distributed over the entire surface and square based, reflecting the twofold symmetry of the substrate surface. Similar square-based pyramidal structures with four equivalent facets are observed following the nanostructuring of Si(110). With Si(111), nanostructure growth occurs preferentially along step edges formed on the vicinal surfaces. Significant differences in the shapes of nanostructures formed on step edges and terraces are related to the different growth mechanisms on the unreconstructed and 7×7 reconstructed domains, respectively.

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