| 1. |
- Kubart, Tomas, 1977-, et al.
(författare)
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On the description of metal ion return in reactive high power impulse magnetron sputtering
- 2021
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Ingår i: Surface & Coatings Technology. - : Elsevier. - 0257-8972 .- 1879-3347. ; 418
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Tidskriftsartikel (refereegranskat)abstract
- Back-attraction of ionized metal is an important process in reactive high power impulse magnetron sputtering (R-HiPIMS). Here, we discuss the implementation of the metal return in balance type models for reactive magnetron sputtering. We show that the existing description of surface processes needs to be modified to satisfy mass conservation. A new steady-state time-averaged model is presented and used to evaluate the effect of the metal return in R-HiPIMS. The results show that the metal return leads to an increased oxide fraction in the deposited coating in R-HiPIMS. This effect can explain the high rate deposition of stoichiometric compounds deposited in the metal mode of operation that has been observed experimentally.
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| 2. |
- Prusakova, Lucie, et al.
(författare)
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Room Temperature Reactive Deposition of InGaZnO and ZnSnO Amorphous Oxide Semiconductors for Flexible Electronics
- 2020
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Ingår i: Coatings. - : MDPI. - 2079-6412. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Amorphous oxide semiconductors (AOSs) are interesting materials which combine optical transparency with high electron mobility. AOSs can be prepared at low temperatures by high throughput deposition techniques such as magnetron sputtering and are thus suitable for flexible transparent electronics such as flexible displays, thin-film transistors, and sensors. In magnetron sputtering the energy input into the growing film can be controlled by the plasma conditions instead of the substrate temperature. Here, we report on magnetron sputtering of InGaZnO (IGZO) and ZnSnO (ZTO) with a focus on the effect of deposition conditions on the film properties. IGZO films were deposited by radio-frequency (RF) sputtering from an oxide target while for ZTO, reactive sputtering from an alloy target was used. All films were deposited without substrate heating and characterized with respect to microstructure, electron mobility, and resistivity. The best as-deposited IGZO films exhibited a resistivity of about 2 x 10(-2) Ohm center dot cm and an electron mobility of 18 cm(2)center dot V-1 center dot s(-1). The lateral distribution of the electrical properties in such films is mainly related to the activity and amount of oxygen reaching the substrate surface as well as its spatial distribution. The lateral uniformity is strongly influenced by the composition and energy of the material flux towards the substrate.
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| 3. |
- Cheng, Fangwen, et al.
(författare)
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Embedding biocatalysts in a redox polymer enhances the performance of dye-sensitized photocathodes in bias-free photoelectrochemical water splitting
- 2024
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- Dye-sensitized photoelectrodes consisting of photosensitizers and molecular catalysts with tunable structures and adjustable energy levels are attractive for low-cost and eco-friendly solar-assisted synthesis of energy rich products. Despite these advantages, dye-sensitized NiO photocathodes suffer from severe electron-hole recombination and facile molecule detachment, limiting photocurrent and stability in photoelectrochemical water-splitting devices. In this work, we develop an efficient and robust biohybrid dye-sensitized NiO photocathode, in which the intermolecular charge transfer is enhanced by a redox polymer. Owing to efficient assisted electron transfer from the dye to the catalyst, the biohybrid NiO photocathode showed a satisfactory photocurrent of 141±17 μA·cm−2 at neutral pH at 0 V versus reversible hydrogen electrode and a stable continuous output within 5 h. This photocathode is capable of driving overall water splitting in combination with a bismuth vanadate photoanode, showing distinguished solar-to-hydrogen efficiency among all reported water-splitting devices based on dye-sensitized photocathodes. These findings demonstrate the opportunity of building green biohybrid systems for artificial synthesis of solar fuels.
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| 4. |
- Cheng, Haoliang, et al.
(författare)
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Atomic Layer Deposition of SnO2 as an Electron Transport Material for Solid-State P-type Dye-Sensitized Solar Cells
- 2022
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Ingår i: ACS Applied Energy Materials. - : American Chemical Society (ACS). - 2574-0962. ; 5:10, s. 12022-12028
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Tidskriftsartikel (refereegranskat)abstract
- Tin oxide (SnO2) as an electron transport material was prepared by atomic layer deposition in dye-sensitized NiO films to fabricate solid-state p-type dye-sensitized solar cells using two organic dyes PB6 and TIP as photosensitizers. Due to the excellent electron mobility and satisfactory penetration of SnO2 material into the NiO film, a record photocurrent density over 1 mA cm–2 was achieved with a power conversion efficiency of 0.14%. The effect of an inserted Al2O3 layer between the dye-sensitized NiO and SnO2 layer on photovoltaic performance of the devices was also investigated. The results suggest that the charge recombination between NiO and SnO2 can be significantly suppressed, showing prolonged charge lifetime and enhanced photovoltage.
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| 5. |
- Comparotto, Corrado, et al.
(författare)
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Chalcogenide Perovskite BaZrS3 : Thin Film Growth by Sputtering and Rapid Thermal Processing
- 2020
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Ingår i: ACS Applied Energy Materials. - : AMER CHEMICAL SOC. - 2574-0962. ; 3:3, s. 2762-2770
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Tidskriftsartikel (refereegranskat)abstract
- Tandem solar cells based on hybrid organic-inorganic metal halide perovskites have reached efficiencies up to 28%, but major concerns for long-term stability and the presence of Pb have raised interest in searching for fully earth-abundant, intrinsic chemically stable, and nontoxic alternatives. With a direct band gap around 1.8 eV and stability in air up to at least 500 degrees C, BaZrS3 is a promising candidate. This work presents the first approach of synthesizing a thin film of such compound by sputtering at ambient temperature with a subsequent rapid thermal process. Despite the short fabrication time, the width of the XRD diffraction peaks and the energy and distribution of the photoluminescence response show comparable crystalline quality to that from bulk synthesis methods. Good crystallization required around 900 degrees C. Such a high temperature could be incompatible with fabrication of tandem solar cells.
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| 6. |
- Comparotto, Corrado, et al.
(författare)
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Synthesis of BaZrS3 Perovskite Thin Films at a Moderate Temperature on Conductive Substrates
- 2022
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Ingår i: ACS Applied Energy Materials. - : American Chemical Society (ACS). - 2574-0962. ; 5:5, s. 6335-6343
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Tidskriftsartikel (refereegranskat)abstract
- Chalcogenide perovskites are being considered for various energy conversion applications, not least photovoltaics. BaZrS3 stands out for its highly stable, earth-abundant, and nontoxic nature. It exhibits a very strong light-matter interaction and an ideal band gap for a top subcell in a two-junction photovoltaic device. So far, thin-film synthesis-necessary for proper optoelectronic characterization as well as device integration-remains underdeveloped. Sputtering has been considered, among others, but the need for an annealing step of at least 900 degrees C has been a cause for concern: such a high temperature could lead to damaging the bottom layers of prospective tandem devices. Still, a solid-state fabrication route has already demonstrated that BaZrS3 can form at much lower temperatures if excess S is present. In this work, sputtered Ba-Zr precursors capped by SnS are sulfurized at under 600 degrees C for 20 min. Although some Sn is still present at the surface after sulfurization, the resulting crystalline quality is comparable to samples synthesized at much higher temperatures. The results are rationalized, and the effect of key process variables is examined. This study represents the first successful synthesis of BaZrS3 perovskite that is compatible with conductive substrates-an important step forward for device integration.
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| 7. |
- Elo, Robin, 1988-, et al.
(författare)
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Tailoring residual stresses in CrNx films on alumina and silicon deposited by high-power impulse magnetron sputtering
- 2020
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Ingår i: Surface & Coatings Technology. - : Elsevier BV. - 0257-8972 .- 1879-3347. ; 397
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Tidskriftsartikel (refereegranskat)abstract
- Chromium nitride films, deposited using reactive magnetron sputtering, were optimised for wear resistance. The performance was measured by scratch resistance and optimised by tailoring the residual stresses. The depositions were carried out with either direct current magnetron sputtering (DCMS) or high-power impulse magnetron sputtering (HiPIMS), and with varying substrate bias and nitrogen gas flow. With DCMS, all films remained under tensile stresses and exhibited poor performance in scratch testing. Although the tensile stresses could be reduced by increasing the nitrogen flow, compressive stresses could only be induced when employing HiPIMS. Substrate bias had a strong effect in HiPIMS in contrast to the DCMS. The effect of the substrate bias in HiPIMS can be explained by the high ionisation of the flux of film forming species. In all cases, increased nitrogen flow favoured formation of CrN over Cr2N. All films showed signs of limited adhesion, which was improved using a titanium interlayer. Cracking across the scratch could be completely avoided for films with lower tensile or compressive stresses, the latter also exhibiting the highest critical load. The results show that it is possible to increase the scratch resistance by tailoring the residual stresses, for which HiPIMS proved a very useful tool.
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| 8. |
- Fernandes, Daniel Filipe Félix, et al.
(författare)
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Photocatalytic activity of TiO2 deposited by reactive HiPIMS with long target-to-substrate distance
- 2023
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Ingår i: Surface & Coatings Technology. - : Elsevier BV. - 0257-8972 .- 1879-3347. ; 467
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Tidskriftsartikel (refereegranskat)abstract
- Reactive High Power Impulse Magnetron Sputtering (HiPIMS) of TiO2 thin films was carried out to investigate the influence of ion parameters and the deposition temperature on the film crystallinity and photocatalytic performance. In order to limit unintentional substrate heating, a deposition setup with long target-to-substrate distance was used. Different HiPIMS pulse configurations, deposition temperatures and substrate bias were evaluated. TiO2 films prepared by pulsed dc magnetron sputtering were used as reference. Films deposited at room temperature were all found to be X-ray amorphous, and a minimum temperature of 200 degrees C was needed for film crystallization irrespective of the mode of operation. This is attributed to the relatively long target-to -substrate distance of 180 mm used in this work. The growth of a specific polymorph was shown to be depen-dent on the operation mode, where a high oxygen partial pressure was ideal for anatase formation. The pho-todegradation rates were, as expected, found to be highest for crystalline samples, where single-and mixed-phase films yielded similar rates. Furthermore, the photodegradation rates of HiPIMS films deposited without substrate heating could be enhanced up to 3 times as compared to the corresponding pulsed dc reference film. The ion assistance in HiPIMS is also beneficial at moderate temperatures, here 200 degrees C, where an improved crystallinity as compared to pdcMS, was observed.
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| 9. |
- Honnali, Sanath Kumar, 1996-
(författare)
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Energy-efficient physical vapor deposition of transition metal nitride thin films
- 2024
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on providing insights into energy-efficient ways of growing protective thin films using physical vapor deposition (PVD) by magnetron sputtering, specifically high-power impulse magnetron sputtering (HiPIMS). This technique involves ionizing the material to be deposited to a high degree. The properties of the film for applications such as protective coatings could thus be controlled by modulating the energy and guiding the ions using electric and magnetic fields, respectively. The multiprincipal element TiZrNbTa nitride system is of interest for its corrosion-resistant coating applications. This material system consists of refractory metals that exhibit different ionic charge states with significant mass contrast. Thus, when sputtered with HiPIMS, the properties of the films strongly depend on the mass and energy of the bombarding metal ions. The transport of these ions to the substrate is influenced by the magnetic field distribution in the chamber. To demonstrate the influence of the magnetron arrangement, the deposition is performed without external heating. Two magnetron arrangements were chosen: a tilted closed-field design with four magnetrons and a single magnetron. The films exhibited different properties depending on the magnetron design used. The single magnetron design induces changes in the preferred orientation of the films from 111 to 200 along with film composition and density. A reduction in residual stress was observed with only a ~6 % degradation in the hardness compared to the closed-field design. I also demonstrate epitaxial growth of TiZrNbTaNx films without external heating. The films were grown with a single magnetron design on single crystal sapphire substrate. Applying a pulsed substrate bias with a long pulse width instead of a constant bias, resulted in low argon (~1 at. %) and oxygen (0.5 at. %) content in the films. In addition, the films exhibited a higher optical absorbance in the near-infrared region than the high-temperature grown films. The total energy consumption for film deposition was reduced by approximately 50 % compared to dc magnetron sputtering (DCMS) at 400°C growth temperature. This reduction is without considering the substrate heating and stabilization phase, which is shorter compared to the industry standard where the entire chamber is heated up to ~500-600°C. These findings are beneficial in designing film growth conditions for energy-efficient processes without compromising film quality. This could also address the challenges of growing high-quality films on temperature-sensitive substrates.
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| 10. |
- Jacobo-Martin, Alejandra, et al.
(författare)
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Resilient moth-eye nanoimprinted antireflective and self-cleaning TiO2 sputter-coated PMMA films
- 2022
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Ingår i: Applied Surface Science. - : Elsevier. - 0169-4332 .- 1873-5584. ; 585
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Tidskriftsartikel (refereegranskat)abstract
- Moth-eye nanostructures are amongst the most remarkable surfaces in nature because of their multi-functionality including antireflection, self-cleaning and bactericidal ability. Moth-eye surfaces consist of subwavelength arrays of tapered nanostructures, which are challenging to reproduce artificially. Nanoimprint lithography is probably one of the most suited technologies for this purpose. However, the poor mechanical resilience and durability of the polymeric nanocones when exposed to the environment, hinders their use in actual applications. To overcome these limitations, this work demonstrates the use of a thin oxide coating over the polymer moth-eye features imprinted on poly methyl methacrylate (PMMA) films. Particularly TiO2 conformal thin film coatings are deposited by unipolar pulsed dc magnetron sputtering over the antireflective nanopatterns acting as encapsulant. The coating, while preserving the antireflective properties, protects the nanostructures against mechanical scratching and improves substantially their thermal stability to over 250 ?. Furthermore, the TiO2 layer provides additional photoinduced self-cleaning functionality and at the same time it protects the matrix from UV photodegradation. The robust and durable antireflective surfaces developed here may find application on solar cells covers, flat panel displays or on optical components.
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| 11. |
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| 12. |
- Keller, Jan, et al.
(författare)
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Wide-Gap Chalcopyrite Solar Cells with Indium Oxide-Based Transparent Back Contacts
- 2022
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Ingår i: Solar RRL. - : John Wiley & Sons. - 2367-198X. ; 6:8
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Tidskriftsartikel (refereegranskat)abstract
- Herein, the performance of wide-gap Cu(In,Ga)Se-2 (CIGS) and (Ag,Cu)(In,Ga)Se-2 (ACIGS) solar cells with In2O3:Sn (ITO) and In2O3:H (IOH) as transparent back contact (TBC) materials is evaluated. Since both TBCs restrict sodium in-diffusion from the glass substrate, fine-tuning of a NaF precursor layer is crucial. It is found that the optimum Na supply is lower for ACIGS than for CIGS samples. An excessive sodium amount deteriorates the solar cell performance, presumably by facilitating GaOx growth at the TBC/absorber interface. The efficiency (eta) further depends on the absorber stoichiometry, with highest fill factors (and eta) reached for close-stoichiometric compositions. An ACIGS solar cell with eta = 12% at a bandgap of 1.44 eV is processed, using IOH as a TBC. The best CIGS device reaches eta = 11.2% on ITO. Due to its very high infrared transparency, IOH is judged superior to ITO for implementation in a top cell of a tandem device. However, while ITO layers maintain their conductivity, IOH films show an increased sheet resistance after absorber deposition. Chemical investigations indicate that incorporation of Se during the initial stage of absorber processing may be responsible for the deteriorated conductivity of the IOH back contact in the final device.
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| 13. |
- Kubart, Tomas, 1977-, et al.
(författare)
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High power impulse magnetron sputtering of diamond-like carbon coatings
- 2020
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Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films. - : American Vacuum Society. - 0734-2101 .- 1520-8559. ; 38:4
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Tidskriftsartikel (refereegranskat)abstract
- High power impulse magnetron sputtering (HiPIMS) of diamond-like carbon coatings is reviewed. Three variations of HiPIMS were used to deposit diamond-like carbon coatings: use of neon as compared to argon for sputtering, very high discharge peak current density in an Ar atmosphere, and the use of bursts of short sputtering pulses. All three variations were able to provide sufficient ion-to-neutral ratios to effectively control the coating quality using substrate bias. The resulting coatings are typically smooth, amorphous, hard (up to 25 GPa), and dense but have low stress (below 2.5 GPa). The coatings exhibit an increased stability at higher temperature (up to 500 °C) compared to the coatings prepared using standard magnetron sputtering. The resulting coatings also exhibited low wear rates in ambient ball-on-disc tests (2.1 × 10−8 mm3 N−1 m−1). These improvements are explained in terms of the rate of sputtered carbon atom ionization in the plasma and material transport to the substrate. However, the chemical bonding in the films is not yet well understood as relatively low sp3 bond content has been observed.
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| 14. |
- Oliveira, Joao, et al.
(författare)
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Correlation between Substrate Ion Fluxes and the Properties of Diamond-Like Carbon Films Deposited by Deep Oscillation Magnetron Sputtering in Ar and Ar plus Ne Plasmas
- 2020
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Ingår i: Coatings. - : MDPI. - 2079-6412. ; 10:10
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Tidskriftsartikel (refereegranskat)abstract
- Recently, the use of Ne as a processing gas has been shown to increase the ionization degree of carbon in High Power Impulse Magnetron Sputtering (HiPIMS) plasmas. In this work, time-resolved measurements of the substrate's current density were carried out in order to study the time evolution of the ionic species arriving at the growing film. The addition of Ne to the plasma resulted in a steep increase of the sp(3)/sp(2) ratio in the films once the Ne contents in the processing atmosphere exceeded 26%. Increasing the Ne content is shown to increase both the total number of C ions generated in the plasmas and the ratio of C/gaseous ions. The time-resolved substrate ion current density was used to evaluate the possibility of substrate biasing synchronizing with the discharge pulses in the HiPIMS process. It is shown that in pure Ar plasmas, substrate biasing should be confined to the time interval between 25 and 40 mu s after the pulse starts, in order to maximize the C+/Ar+ ratio bombarding the substrate and minimize the formation of film stresses. However, Ne addition to the processing gas shortens the traveling time of the carbon species towards the substrate, reducing the separation between the gaseous and carbon ion arrival times.
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| 15. |
- Ravensburg, Anna Lena
(författare)
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Growth of high quality Fe thin films : A study of the effect of mismatch strain on the physical properties of Fe
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The work in this licentiate is devoted to investigating the epitaxial growth of thin Fe layers on MgAl2O4 (001) and MgO (001) substrates using dc magnetron sputtering. The aim is to qualitatively and quantitatively determine the crystal quality of the grown Fe layers depending on their thickness, substrate material, and selected deposition parameters. The effect of the crystal quality on the magnetic and electronic transport properties is discussed. The structural characterization of the epitaxial Fe thin films is carried out by x-ray reflectometry and diffraction as well as transmission electron microscopy. X-ray scattering measurements and analysis with related models allow for a quantitative determination of layering, crystal quality, and strain profiles in the growing Fe. Magnetic properties are determined using a combination of longitudinal magneto-optical Kerr effect measurements, Kerr microscopy, and scanning electron microscopy with polarization analyser. Electronic transport properties are characterized by four-point probe measurements of the thin films. The epitaxial growth of Fe is found to be highly substrate dependent: Fe layers grown on MgAl2O4 have a significantly higher crystal quality, as compared to Fe grown on MgO. The difference in crystal quality is attributed to different strain states in Fe, which is supported by theoretical calculations of the critical thickness on both substrates. Moreover, an anomalous elastic response in Fe at the thin film limit is found. The magnetic properties of Fe are weakly reflecting the differences in crystal quality of the Fe layers. However, the difference in crystal quality affects the electronic transport properties. The results of this study on epitaxial Fe layers can provide insights into strain and defect engineering in Fe thin films, which can additionally serve as model systems for finite size effects.
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| 16. |
- Vethaak, T. D., et al.
(författare)
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Influence of substrate-induced thermal stress on the superconducting properties of V3Si thin films
- 2021
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Ingår i: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 129:10
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Tidskriftsartikel (refereegranskat)abstract
- Thin films of superconducting V3Si were prepared by means of RF sputtering from a compound V3Si target at room temperature onto sapphire and oxide-coated silicon wafers, followed by rapid thermal processing under secondary vacuum. The superconducting properties of the films thus produced are found to improve with annealing temperature, which is ascribed to a reduction in defects in the polycrystalline layer. Critical temperatures (Tc) up to 15.3 K were demonstrated after thermal processing, compared to less than 1 K after deposition. The Tc was always found to be lower on the silicon wafers, by on average 1:9+ 0:3 K for the annealed samples. This difference, as well as a broadening of the superconducting transitions, is nearly independent of the annealing conditions. In situ XRD measurements reveal that the silicide layer becomes strained upon heating due to a mismatch between the thermal expansion of the substrate and that of V3Si. Taking into account the volume reduction due to crystallization, this mismatch is initially larger on sapphire, though stress relaxation allows the silicide layer to be in a relatively unstrained state after cooling. On oxidized silicon, however, no clear evidence of relaxation upon cooling is observed, and V3Si ends up with an out-of-plane strain of 0.3% at room temperature. This strain increases as the sample is cooled down to cryogenic temperatures, though the deformation of the polycrystalline layer is expected to be highly inhomogeneous. Taking into account also the reported occurrence of a Martensitic transition just above the critical temperature, this extrapolated strain distribution is found to closely match an existing model of the strain dependence of A-15 superconducting compounds.
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| 17. |
- Vethaak, T. D., et al.
(författare)
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Superconducting V3Si for quantum circuit applications
- 2021
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Ingår i: Microelectronic Engineering. - : Elsevier. - 0167-9317 .- 1873-5568. ; 244
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Tidskriftsartikel (refereegranskat)abstract
- V3Si thin films are known to be superconducting with transition temperatures up to 15 K, depending on the annealing temperature and the properties of the substrate underneath. Here we investigate the film structural properties with the prospect of further integration in silicon technology for quantum circuits. Two challenges have been identified: (i) the large difference in thermal expansion coefficient between V3Si and the Si substrate leads to large thermal strains after thermal processing, and (ii) the undesired silicide phase VSi2 forms when V3Si is deposited on silicon. The first of these is studied by depositing layers of 200 nm V3Si on wafers of sapphire and oxidized silicon, neither of which react with the silicide. These samples are then heated and cooled between room temperature and 860 degrees C, during which in-situ XRD measurements are performed. Analysis reveals a highly nonlinear stress development during heating with contributions from crystallization and subsequent grain growth, as well as the thermal expansion mismatch between silicide and substrate, while the film behaves thermoelastically during cooling. The second challenge is explored by depositing films of 20, 50, 100 and 200 nm of V3Si on bulk silicon. For each thickness, six samples are prepared, which are then annealed at temperatures between 500 and 750 degrees C, followed by measurements of their resistivity, residual resistance ratio and superconducting critical temperature. A process window is identified for silicide thicknesses of at least 100 nm, within which a trade-off needs to be made between the quality of the V3Si film and its consumption by the formation of VSi2.
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| 18. |
- Vitelaru, Catalin, et al.
(författare)
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A Strategy for Alleviating Micro Arcing during HiPIMS Deposition of DLC Coatings
- 2020
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Ingår i: Materials. - : MDPI. - 1996-1944. ; 13:5
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we investigate the use of high power impulse magnetron sputtering (HiPIMS) for the deposition of micrometer thick diamond like carbon (DLC) coatings on Si and steel substrates. The adhesion on both types of substrates is ensured with a simple Ti interlayer, while the energy of impinging ions is adjusted by using RF (Radio Frequency) biasing on the substrate at -100 V DC self-bias. Addition of acetylene to the working Ar+Ne atmosphere is investigated as an alternative to Ar sputtering, to improve process stability and coatings quality. Peak current is maintained constant, providing reliable comparison between different deposition conditions used in this study. The main advantages of adding acetylene to the Ar+Ne gas mixture are an increase of deposition rate by a factor of 2, when comparing to the Ar+Ne process. Moreover, a decrease of the number of surface defects, from similar to 40% surface defects coverage to similar to 1% is obtained, due to reduced arcing. The mechanical and tribological properties of the deposited DLC films remain comparable for all investigated gas compositions. Nanoindentation hardness of all coatings is in the range of 25 to 30 GPa, friction coefficient is between 0.05 and 0.1 and wear rate is in the range of 0.47 to 0.77 x 10(-6) mm(3) N(-1)m(-1).
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| 19. |
- Wrede, Sina, et al.
(författare)
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A solid-state p–n tandem dye-sensitized solar cell
- 2024
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Ingår i: Sustainable Energy & Fuels. - : Royal Society of Chemistry. - 2398-4902. ; 8:5, s. 1004-1011
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Tidskriftsartikel (refereegranskat)abstract
- The development of p–n tandem dye-sensitized solar cells (t-DSCs) offers the potential for substantial open-circuit voltages, holding great promise for a wide range of applications, particularly in the fields of photovoltaics and photoelectrochemical devices. Most reported t-DSCs are liquid-based, and suffer from unsatisfactory stability due to the leakage of liquid electrolytes and photovoltage that is limited to the energy difference of the two utilized semiconductors. In this study, we present the first realization of a solid-state p–n tandem dye-sensitized solar cell that incorporates both p-type and n-type solid-state dye-sensitized solar cells (ssDSCs) by using a transparent indium-doped tin oxide (ITO) back contact for both sides. Notably, this tandem system shows a remarkable open-circuit voltage of 1.4 V, surpassing the constraints of its liquid-based counterparts. Although the performance variations between p-ssDSCs and n-ssDSCs hint at challenges related to charge recombination and the efficiency of p-ssDSCs, this study underscores the significant potential inherent in solid-state tandem configurations.
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