0000000001095322

AUTHOR

Pekka Simell

showing 4 related works from this author

Low-temperature molecular layer deposition using monifunctional aromatic precursors and ozone-based ring-opening reactions

2017

Molecular layer deposition (MLD) is an increasingly used deposition technique for producing thin coatings consisting of purely organic or hybrid inorganic-organic materials. When organic materials are prepared, low deposition temperatures are often required to avoid decomposition, thus causing problems with low vapor pressure precursors. Monofunctional compounds have higher vapor pressures than traditional bi- or trifunctional MLD precursors, but do not offer the required functional groups for continuing the MLD growth in subsequent deposition cycles. In this study, we have used high vapor pressure monofunctional aromatic precursors in combination with ozone-triggered ring-opening reactions…

Vapor pressureHydrostatic pressure02 engineering and technologyphenols01 natural sciencesdepositionchemistry.chemical_compoundhybrid materialsElectrochemistryGeneral Materials Sciencecharacterizationinfrared spectroscopyta116Spectroscopyring opening reactionTrifluoromethylvapor pressurehybrid organic-inorganiclow-temperatureSurfaces and Interfacesself assembly021001 nanoscience & nanotechnologyCondensed Matter Physicsdecay (organic)hydrostatic pressure0210 nano-technologyHybrid materialLayer (electronics)Inorganic chemistryta221mechanismnegative ions010402 general chemistrycomplex mixturesinorganic coatingsBenzaldehydeAtomic layer depositionPhenolta216ta115ta114aromatic compoundsmonofunctional aromaticstemperature0104 chemical sciencesozonechemistryALDatomic layer depositionMLDLangmuir
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Atomic layer deposition of Ti-Nb-O thin films onto electrospun fibers for fibrous and tubular catalyst support structures

2018

Here, the authors report on the preparation of core-shell carbon-ceramic fibrous as well as ceramic tubular catalyst supports utilizing electrospinning and atomic layer deposition (ALD). In this paper, ALD of Ti-Nb-O thin films using TiCl4, Nb(OEt)5, and H2O as precursors is demonstrated. According to the time-of-flight-elastic recoil detection analysis and Rutherford backscattering spectrometry, carbon and hydrogen impurities were relatively low, but depend on the pulsing ratio of the precursors. Optimized ALD process was used for coating of sacrificial electrospun polyvinyl alcohol (PVA) template fibers to yield tubular Ti-Nb-O structures after thermal or solution based PVA removal. Anoth…

Materials scienceCatalyst supportelectrospun fibers02 engineering and technologyThermal treatmentengineering.materialsupport structures010402 general chemistry01 natural scienceschemistry.chemical_compoundAtomic layer depositionCoatingThin filmta216ta114PolyacrylonitrileSurfaces and Interfacesatomikerroskasvatus021001 nanoscience & nanotechnologyCondensed Matter PhysicsRutherford backscattering spectrometryElectrospinningfibrous and tubular catalyst0104 chemical sciencesSurfaces Coatings and Filmsthin filmschemistryChemical engineeringatomic layer depositionengineeringohutkalvot0210 nano-technologyJournal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films
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Low-temperature atomic layer deposition of SiO2/Al2O3 multilayer structures constructed on self-standing films of cellulose nanofibrils

2018

In this paper, we have optimized a low-temperature atomic layer deposition (ALD) of SiO 2 using AP-LTO® 330 and ozone (O 3 ) as precursors, and demonstrated its suitability to surface-modify temperature-sensitive bio-based films of cellulose nanofibrils (CNFs). The lowest temperature for the thermal ALD process was 80°C when the silicon precursor residence time was increased by the stop-flow mode. The SiO 2 film deposition rate was dependent on the temperature varying within 1.5–2.2 Å cycle −1 in the temperature range of 80–350°C, respectively. The low-temperature SiO 2 process that resulted was combined with the conventional trimethyl aluminium + H 2 O process in order to prepare thin mul…

Water sensitivityMaterials scienceDiffusion barrierSiliconGeneral Mathematicsta221General Physics and Astronomychemistry.chemical_element02 engineering and technology01 natural sciencesOxygenAtomic layer depositionchemistry.chemical_compoundnanorakenteetHybrid multilayersSiO0103 physical sciencesCelluloseta216diffusion barrierta218low-temperature atomic layer depositionDiffusion barrierLow-temperature atomic layer deposition010302 applied physicsta214ta114water sensitivityta111General Engineeringcellulose nanofibrilsAtmospheric temperature range021001 nanoscience & nanotechnologyhybrid multilayerschemistryChemical engineeringCellulose nanofibrilsohutkalvotSiO20210 nano-technologyLayer (electronics)Water vaporPhilosophical Transactions of the Royal Society A : Mathematical Physical and Engineering Sciences
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Low-temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-based Ring Opening Reactions

2017

Molecular layer deposition (MLD) is an increasingly used deposition technique for producing thin coatings consisting of purely organic or hybrid inorganic–organic materials. When organic materials are prepared, low deposition temperatures are often required to avoid decomposition, thus causing problems with low vapor pressure precursors. Monofunctional compounds have higher vapor pressures than traditional bi- or trifunctional MLD precursors, but do not offer the required functional groups for continuing the MLD growth in subsequent deposition cycles. In this study, we have used high vapor pressure monofunctional aromatic precursors in combination with ozone-triggered ring-opening reactions…

ring opening reactionhybrid organic-inorganicALDMLDmonofunctional aromaticslow-temperaturemechanism
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