Article
Materials Science, Multidisciplinary
Koichi Tanaka, Michael E. Liao, Angel Aleman, Hicham Zaid, Mark S. Goorsky, Suneel Kodambaka
Summary: Highly-oriented B1-TaC(111) and rhombohedral-Ta3C2(0001) phases were successfully formed on Al2O3(0001) substrates during ultrahigh vacuum dc magnetron sputtering, with different film surface structures observed under varying ethylene partial pressures. Ta3C2 phase was found to be more stable than TaC phase on the Al2O3(0001) substrate.
Article
Materials Science, Multidisciplinary
Marc Stevens, Hanna Pazniak, Alexander Jemiola, Merve Felek, Michael Farle, Ulf Wiedwald
Summary: Pulsed Laser Deposition was used to grow phase pure and epitaxial Cr2AlC MAX phase thin films on MgO(111) and Al2O3(0001). The results demonstrate the potential of this method for the growth of epitaxial MAX phase thin films, with the film thickness affecting the material properties significantly.
MATERIALS RESEARCH LETTERS
(2021)
Article
Chemistry, Physical
J. E. Prieto, E. M. Trapero, P. Prieto, E. Garcia-Martin, G. D. Soria, P. Galan, J. de la Figuera
Summary: In this work, the growth of epitaxial Ru films on single-crystalline Al2O3 substrates by magnetron sputtering was investigated. The films were characterized using Rutherford backscattering spectrometry. The results showed that the thicker films exhibited a well-defined epitaxial relation with the substrate and high crystal quality, comparable to the Ru single crystal, while thinner films showed some degree of dechanneling.
APPLIED SURFACE SCIENCE
(2022)
Article
Physics, Applied
Fangdi Wen, Tsung-Chi Wu, Xiaoran Liu, Michael Terilli, Mikhail Kareev, Jak Chakhalian
Summary: This study achieved successful layer-by-layer growth of frustrated quantum pyrochlores thin films, confirming their high crystallinity and proper chemical composition, which offers a new platform to explore strain and magnetic field-dependent properties in the quasi-2D limit.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Ik-Jae Lee, Hee Seob Kim, Young Duck Yun, Seen-Woong Kang, Hyo-Yun Kim, Hyuk Chae Kwon, Jin Woo Kim, Mankil Joo, Younghak Kim
Summary: Epitaxial Cu thin films were grown on Al2O3 (0001) substrate, with the surface unaffected by oxygen adsorption from the air. The electrical resistivity decreased as the thickness of Cu layer increased, with the trend described well by a second-order exponential function.
Article
Materials Science, Multidisciplinary
Sudhanshu Gautam, V Aggarwal, Bheem Singh, Rahul Kumar, J. S. Tawale, B. S. Yadav, R. Ganesan, V. N. Singh, S. P. Singh, M. Senthil Kumar, S. S. Kushvaha
Summary: Thin films of Bi2Se3 were deposited on various substrates using magnetron sputtering. The films were found to have good crystalline quality, pure rhombohedral phase, and truncated hexagonal morphology. The optical bandgap of the films was in the range of 1.40-1.48 eV, and they showed potential for the development of futuristic devices.
JOURNAL OF MATERIALS RESEARCH
(2023)
Article
Nanoscience & Nanotechnology
Hanna Pazniak, Marc Stevens, Martin Dahlqvist, Benjamin Zingsem, Lidia Kibkalo, Merve Felek, Sergey Varnakov, Michael Farle, Johanna Rosen, Ulf Wiedwald
Summary: In this study, chemical stability in the (Cr1-xFex)(2)AlC MAX phase system was modeled using density functional theory, and nanolaminated (Cr1-xFex)(2)AlC MAX phase thin films were successfully synthesized with different Fe contents. Experimental results revealed a maximum Fe solubility of 3.4 at % and metallic behavior in the thin films, making them promising candidates for highly conductive coatings.
ACS APPLIED NANO MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Aida Serrano, Jesus Lopez-Sanchez, Iciar Arnay, Rosalia Cid, Maria Vila, Eduardo Salas-Colera, German R. Castro, Juan Rubio-Zuazo
Summary: This work demonstrates the functional character of complex alpha-Fe2O3(0001)/SrTiO3(111) and Au(111) islands/alpha-Fe2O3(0001)/SrTiO3(111) heterostructures as gas sensors at room temperature. The epitaxial growth of Au islands and alpha-Fe2O3 thin film on SrTiO3(111) substrates is investigated for their gas-sensing response. The incorporation of epitaxial Au islands on top of the alpha-Fe2O3(0001) layer enhances gas-sensing activity under CO and CH4 gas exposure, with the response to CO gas being higher than to CH4 gas.
Article
Nanoscience & Nanotechnology
Aditya Deshpande, Koki Hojo, Koichi Tanaka, Pedro Arias, Hicham Zaid, Michael Liao, Mark Goorsky, Suneel Kumar Kodambaka
Summary: By growing van der Waals-bonded hexagonal boron nitride (hBN) layers on Al2O3 (0001) substrates and depositing MoSx layers via reactive magnetron sputtering, researchers obtain MoSx multilayers with higher crystalline quality on hBN/Al2O3 (0001) compared to bare Al2O3 (0001). The presence of hBN buffer layer enhances surface diffusion, resulting in improved crystallinity of MoSx layers. These findings have implications for nanoelectronic device fabrication.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ya. Yu. Matyash, A. S. Anokhin, A. V. Pavlenko, N. V. Malomyzheva
Summary: The lattice dynamics and dielectric properties of Ba0.5Sr0.5Nb2O6 ferroelectric thin films grown by high-frequency RF-deposition on a Pt(111)/Al2O3 substrate were investigated. The film exhibited a higher transition temperature from the ferroelectric to the paraelectric phase compared to the bulk material. The Ba0.5Sr0.5Nb2O6/Pt/Al2O3 heterostructure showed behavior characteristic of a ferroelectric relaxor, with a detected Burns temperature of 180-190 degrees Celsius.
Article
Chemistry, Physical
C. Ruano Merchan, T. T. Dorini, F. Brix, L. Pasquier, M. Jullien, D. Pierre, S. Andrieu, K. Dumesnil, S. S. Parapari, S. Sturm, J. Ledieu, M. Sicot, O. Copie, E. Gaudry, V Fournee
Summary: This study investigated the formation of new complex phases in thin films deposited on Al2O3(0001) substrate by pulsed laser deposition followed by high temperature annealing. The discovered phases include a large square approximant and a 2D hexagonal approximant, both constructed from similar basic tiles. The research also revealed differences in electronic structure and adhesion properties of the two approximants, suggesting unique chemical and physical characteristics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Guang Yang, Jun-Shuai Chai, Kun Bu, Li-Fang Xu, Jian-Tao Wang
Summary: This study presents a systematic investigation of the structural, magnetic, and electronic properties of EuSi2 thin films on the Si(111) surface using ab initio calculations. The calculations show that the AA stacking structure is more favorable for EuSi2 thin films. The Eu2+ ions exhibit ferromagnetic coupling within each layer and antiferromagnetic coupling across adjacent silicene layers. The monolayer EuSi2 thin film is a semiconductor with an indirect surface band gap, while the multilayer EuSi2 thin films exhibit metallic behavior.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Koichi Tanaka, Pedro Arias, Koki Hojo, Tomoyasu Watanabe, Michael E. Liao, Angel Aleman, Hicham Zaid, Mark S. Goorsky, Suneel Kumar Kodambaka
Summary: We report a phenomenon in which thin films sputter deposited on single-crystalline Al2O3(0001) substrates exposed to borazine show higher orientation compared to those grown on bare Al2O3(0001). This was observed in Pd, Mo, and Ta2C thin films grown on Al2O3(0001). Interestingly, intermittent exposure to borazine during the growth of Ta2C thin films leads to better crystallinity than direct deposition. We attribute these results to enhanced adatom mobilities on, and with, surfaces to borazine during deposition.
Article
Materials Science, Ceramics
Antonio Diaz-Parralejo, M. Angeles Diaz-Diez, Jose Sanchez-Gonzalez, Antonio Macias-Garcia, Juan Pablo Carrasco-Amador
Summary: This study prepared thin multilayer coatings of ZrO2-Y2O3-Al2O3 using the sol-gel method and dip-coating technique, investigating the influence of Al2O3 incorporation on the films. It was found that increasing alumina content improved the toughness and resistance to thermal shock of the coatings.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Tae Yeon Kim, Je Oh Choi, Gopinathan Anoop, Jaegyu Kim, Seong Min Park, Shibnath Samanta, Wooseon Choi, Young-Min Kim, Seungbum Hong, Ji Young Jo
Summary: In this study, ultrahigh energy density singlecomponent Sn-doped BaTiO3 (BTS) epitaxial thin film capacitors were successfully developed, achieving an ultrahigh energy density of 92.5 J/cm3 and energy efficiencies above 78%. These excellent results were attributed to the formation of multi-nanodomains accompanied by delayed polarization saturation, low remnant polarization, high breakdown strength, and high cycling stability. Engineering multi-nanodomains through chemical doping and epitaxial orientation is a facile approach to develop energy-efficient ultrahigh energy density capacitors.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Coatings & Films
Arun Haridas Choolakkal, Hans Hogberg, Jens Birch, Henrik Pedersen
Summary: We demonstrate the conformal chemical vapor deposition of boron carbide thin films using triethylboron as a single source precursor on silicon substrates with 8:1 aspect-ratio morphologies. The films deposited at temperatures below 450°C exhibit excellent step coverage, attributed to the low reaction probability at lower temperatures. The boron carbide films are determined to have B-B, B-C, C-B, and C-C chemical bonds and show a boron-rich composition of approximately B5C.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Coatings & Films
Xiao Li, Ivan Petrov, Lars Hultman, Grzegorz Greczynski
Summary: Hybrid high-power impulse and dc magnetron co-sputtering (HiPIMS/DCMS) with synchronized substrate bias can reduce energy consumption and enable coatings on temperature-sensitive substrates. Direct evidence shows that W+ ion irradiation plays a crucial role in the densification of Ti0.31Al0.60W0.09N films.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Multidisciplinary
Samira Dorri, Jens Birch, Fredrik Eriksson, Justinas Palisaitis, Per O. A. Persson, Babak Bakhit, Lars Hultman, Naureen Ghafoor
Summary: In this study, CrBx/TiBy (0001) diboride superlattices were grown epitaxially on Al2O3 substrates using direct-current magnetron sputter epitaxy. The effects of period and B/TM ratio on the structural quality were investigated. It was found that increasing the relative thickness of TiBy improved the superlattice quality but excessive TiBy led to structural distortion. On the other hand, increasing the relative thickness of CrBx enhanced the superlattice quality and hindered the formation of B-rich boundaries. The hardness values of the superlattices ranged from 29-34 GPa.
MATERIALS & DESIGN
(2023)
Article
Materials Science, Multidisciplinary
Sjoerd Broekhuijsen, Naureen Ghafoor, Alexei Vorobiev, Jens Birch, Fredrik Eriksson
Summary: This study shows that the interface width of Ni/Ti multilayers can be improved by incorporating low-neutron-absorbing 11B4C and applying a modulated ion-assistance scheme. The accumulated roughness is eliminated in the 11B4C-containing multilayers, resulting in a mean interface width of 4.5 angstrom and an increase in reflectivity at the first Bragg peak by a factor of 2.3 and 1.5 for neutron and X-ray measurements, respectively.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Fredrik Eriksson, Naureen Ghafoor, Sjoerd Broekhuijsen, Grzegorz Greczynski, Norbert Schell, Jens Birch
Summary: By modulating ion assistance, the interface width of Ni/Ti broad band neutron multilayer supermirrors can be reduced, leading to improved optical contrast and minimum layer thickness.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Naureen Ghafoor, Samira Dorri, Justinas Palisaitis, Lina Rogstrom, Babak Bakhit, Grzegorz Greczynski, Lars Hultman, Jens Birch
Summary: Metastable super-saturated Zr1_xAlxN alloys tend to phase separate into the equilibrium cubic (c) ZrN and wurtzite (w) AlN. Different transformation paths were observed depending on the deposition method and post-deposition annealing. The surface segregation effects and secondary phase transformations were studied using in situ high-energy synchrotron wide-angle X-ray scattering and analytical transmission electron microscopy. The results showed the formation of AlN-ZrN labyrinthine structure and the inhibition of c-AlN formation during transformation.
Article
Physics, Applied
G. Greczynski, L. Hultman, I. Petrov
Summary: The quest for reducing energy consumption during thin film growth is important for sustainable development goals. Metal ion irradiation has been shown to be effective in densifying films grown without external heating. This Perspective provides an overview of the novel film growth method and discusses the role of metal ion mass, energy, momentum, and concentration.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Sanjay Nayak, Sathish Kumar Shanmugham, Ivan Petrov, Johanna Rosen, Per Eklund, Jens Birch, Arnaud le Febvrier
Summary: The epitaxial growth of boron rich hexagonal zirconium diborides (h-ZrB2+delta) thin films on Si(111) substrates using the magnetron co-sputtering technique with elemental zirconium and boron is reported. The effect of process temperature (700-900 degrees C) on the compositions and epitaxy quality was investigated. The experimental results showed that an epitaxial thin film of h-ZrB2+delta can be grown on Si(111) substrate using a magnetron co-sputtering technique at a relatively low processing temperature (700 degrees C) and has the potential to be used as a template for III-nitride growth on Si substrates.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Coatings & Films
Vladyslav Rogoz, Oleksandr Pshyk, Bartosz Wicher, Justinas Palisaitis, Jun Lu, Daniel Primetzhofer, Ivan Petrov, Lars Hultman, Grzegorz Greczynski
Summary: The traditional method for synthesizing high-entropy sublattice nitride (HESN) coatings is expensive and inflexible. This study demonstrates a new approach to grow HESN films using rotating substrates and elemental targets arranged in a multicathode configuration, which reduces costs and achieves compositional uniformity.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Coatings & Films
Hwan-Seok Seo, Taeyoon Lee, Hyungjun Kim, Ivan Petrov, J. E. Greene
Summary: We investigated the phase composition of HfNx and the effects of low-energy ion irradiation on the microstructure of polycrystalline layers. The results show that the phases in the layers change with increasing x, and the properties of the layers are influenced by ion irradiation.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Coatings & Films
Smita G. Rao, Pascal Manuel Illgner, Robert Boyd, Gyula Nagy, Philippe Djemia, Daniel Primetzhofer, Ivan Petrov, Arnaud le Febvrier, Per Eklund
Summary: Low-temperature epitaxial growth of multicomponent alloy-based thin films is a challenging task in materials science, which is crucial for understanding the fundamental properties of these complex materials. In this study, Cantor nitride (CrMnFeCoNi)N thin films were epitaxially grown on MgO(100) substrates at low deposition temperature using magnetic-field-assisted dc-magnetron sputtering. The epitaxial growth was observed as the ion flux was increased.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Materials Science, Multidisciplinary
Jui-che Chang, Eric Nestor Tseng, Yi-ling Lo, Sanjay Nayak, Daniel Lundin, Per O. A. Persson, Ray-hua Horng, Lars Hultman, Jens Birch, Ching-lien Hsiao
Summary: By using a high-quality AlN buffer layer, the threading dislocation density of sputtered GaN films can be reduced, leading to an improvement in the crystal quality of GaN.
Article
Multidisciplinary Sciences
Grzegorz Greczynski, Oleksandr Pshyk, Lars Hultman
Summary: X-ray photoelectron spectroscopy (XPS) spectra of solid samples are usually referenced to the spectrometer Fermi level (FL). However, for insulating samples, this method is not feasible. By depositing insulating amorphous alumina films on conducting substrates, it is found that the alumina energy levels align with the vacuum level, providing a solution to the binding energy reference problem for reliable assessment of chemical bonding.
