Growth and Characterisation Studies of Eu3O4 Thin Films Grown on Si/SiO2 and Graphene

We report the growth, structural and magnetic properties of the less studied Eu-oxide phase, Eu3O4, thin films grown on a Si/SiO2 substrate and Si/SiO2/graphene using molecular beam epitaxy. The X-ray diffraction scans show that highly textured crystalline Eu3O4(001) films are grown on both substrates, whereas the film deposited on graphene has a better crystallinity than that grown on the Si/SiO2 substrate. The SQUID measurements show that both films have a Curie temperature of ∼5.5±0.1 K, with a magnetic moment of ∼320 emu/cm3 at 2 K. The mixed valence of the Eu cations has been confirmed by the qualitative analysis of the depth-profile X-ray photoelectron spectroscopy measurements with the Eu2+:Eu3+ ratio of 28:72. However, surprisingly, our films show no metamagnetic behaviour as reported for the bulk and powder form. Furthermore, the microscopic optical images and Raman measurements show that the graphene underlayer remains largely intact after the growth of the Eu3O4 thin films.

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A novel and potentially scalable CVD-based route towards SnO2:Mo thin films as transparent conducting oxides

Journal of Materials Science ◽

10.1007/s10853-021-06269-3 ◽

2021 ◽

Author(s):

Tianlei Ma ◽

Marek Nikiel ◽

Andrew G. Thomas ◽

Mohamed Missous ◽

David J. Lewis

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Mixed Valence ◽

Chemical Vapour ◽

X Ray Diffraction ◽

X Ray ◽

Conducting Oxides ◽

Valence States ◽

3 Omega ◽

First Time

AbstractIn this report, we prepared transparent and conducting undoped and molybdenum-doped tin oxide (Mo–SnO2) thin films by aerosol-assisted chemical vapour deposition (AACVD). The relationship between the precursor concentration in the feed and in the resulting films was studied by energy-dispersive X-ray spectroscopy, suggesting that the efficiency of doping is quantitative and that this method could potentially impart exquisite control over dopant levels. All SnO2 films were in tetragonal structure as confirmed by powder X-ray diffraction measurements. X-ray photoelectron spectroscopy characterisation indicated for the first time that Mo ions were in mixed valence states of Mo(VI) and Mo(V) on the surface. Incorporation of Mo6+ resulted in the lowest resistivity of $$7.3 \times 10^{{ - 3}} \Omega \,{\text{cm}}$$ 7.3 × 10 - 3 Ω cm , compared to pure SnO2 films with resistivities of $$4.3\left( 0 \right) \times 10^{{ - 2}} \Omega \,{\text{cm}}$$ 4.3 0 × 10 - 2 Ω cm . Meanwhile, a high transmittance of 83% in the visible light range was also acquired. This work presents a comprehensive investigation into impact of Mo doping on SnO2 films synthesised by AACVD for the first time and establishes the potential for scalable deposition of SnO2:Mo thin films in TCO manufacturing. Graphical abstract

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Effect of Substrate Temperature on Structural and Optical Properties of ZnO:Co Thin Films Fabricated by Laser Molecular Beam Epitaxy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.64 ◽

2013 ◽

Vol 834-836 ◽

pp. 64-69

Author(s):

Xian Gang Wang

Keyword(s):

Thin Films ◽

Molecular Beam Epitaxy ◽

Substrate Temperature ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

Axis Orientation ◽

X Ray ◽

Laser Molecular Beam Epitaxy

We synthesized ZnO:Co thin films on sapphire (0001) substrates by laser molecular beam epitaxy (LMBE) method. X-ray diffraction (XRD) spectra indicated that all samples possessed wurtzite structure with the preferential c-axis-orientation and the value of the c-axis lattice decreased with increasing substrate temperature. UVvis transmittance spectra and X-ray photoelectron spectroscopy (XPS) implied that Co2+ions incorporated into ZnO lattice with substitution for Zn2+ions and the non-bivalent Zn existed in as-prepared thin films. Two emission bands located at 418 nm (2.97 eV) and 490 nm (2.53 eV) were observed from the photoluminescence (PL) spectra of all samples. The two emission bands were in relation to Zn interstitials and the complex of VOand Zni(VOZni). The quantity of the Zn interstitials remained mostly invariable as substrate temperature increased.

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Reactive Dual Magnetron Sputtering: A Fast Method for Preparing Stoichiometric Microcrystalline ZnWO4 Thin Films

Surfaces ◽

10.3390/surfaces4020013 ◽

2021 ◽

Vol 4 (2) ◽

pp. 106-114

Author(s):

Yannick Hermans ◽

Faraz Mehmood ◽

Kerstin Lakus-Wollny ◽

Jan P. Hofmann ◽

Thomas Mayer ◽

...

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Fast Method ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Post Annealing ◽

Rf Signal ◽

First Time

Thin films of ZnWO4, a promising photocatalytic and scintillator material, were deposited for the first time using a reactive dual magnetron sputtering procedure. A ZnO target was operated using an RF signal, and a W target was operated using a DC signal. The power on the ZnO target was changed so that it would match the sputtering rate of the W target operated at 25 W. The effects of the process parameters were characterized using optical spectroscopy, X-ray diffraction, and scanning electron microscopy, including energy dispersive X-ray spectroscopy as well as X-ray photoelectron spectroscopy. It was found that stoichiometric microcrystalline ZnWO4 thin films could be obtained, by operating the ZnO target during the sputtering procedure at a power of 55 W and by post-annealing the resulting thin films for at least 10 h at 600 °C. As FTO coated glass substrates were used, annealing led as well to the incorporation of Na, resulting in n+ doped ZnWO4 thin films.

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Optical properties of anatase TiO2 films modified by N ion implantation

Canadian Journal of Physics ◽

10.1139/p11-136 ◽

2012 ◽

Vol 90 (1) ◽

pp. 39-43 ◽

Cited By ~ 2

Author(s):

X. Xiang ◽

D. Chang ◽

Y. Jiang ◽

C.M. Liu ◽

X.T. Zu

Keyword(s):

Thin Films ◽

Ion Implantation ◽

Photoelectron Spectroscopy ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

X Ray ◽

Atomic Force ◽

Light Region ◽

Uv Visible ◽

Substrate Temperatures

Anatase TiO2 thin films are deposited on K9 glass samples at different substrate temperatures by radio frequency magnetron sputtering. N ion implantation is performed in the as-deposited TiO2 thin films at ion fluences of 5 × 1016, 1 × 1017, and 5 × 1017 ions/cm2. X-ray diffraction, atomic force microscope, X-ray photoelectron spectroscopy (XPS), and UV–visible spectrophotometer are used to characterize the films. With increasing N ion fluences, the absorption edges of anatase TiO2 films shift to longer wavelengths and the absorbance increases in the visible light region. XPS results show that the red shift of TiO2 films is due to the formation of N–Ti–O compounds. As a result, photoactivity is enhanced with increasing N ion fluence.

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Structural and Electrochemical Properties of Lithium Nickel Oxide Thin Films

Journal of Chemistry ◽

10.1155/2014/824083 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Gyu-bong Cho ◽

Tae-hoon Kwon ◽

Tae-hyun Nam ◽

Sun-chul Huh ◽

Byeong-keun Choi ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrochemical Properties ◽

Discharge Capacity ◽

Oxygen Deficiency ◽

Oxide Phase ◽

Rf Magnetron Sputtering ◽

X Ray Diffraction ◽

X Ray ◽

Lithium Nickel Oxide

LiNiO2thin films were fabricated by RF magnetron sputtering. The microstructure of the films was determined by X-ray diffraction and field-emission scanning electron microscopy. The electrochemical properties were investigated with a battery cycler using coin-type half-cells. The LiNiO2thin films annealed below 500°C had the surface carbonate. The results suggest that surface carbonate interrupted the Li intercalation and deintercalation during charge/discharge. Although the annealing process enhanced the crystallization of LiNiO2, the capacity did not increase. When the annealing temperature was increased to 600°C, the FeCrNiO4oxide phase was generated and the discharge capacity decreased due to an oxygen deficiency in the LiNiO2thin film. The ZrO2-coated LiNiO2thin film provided an improved discharge capacity compared to bare LiNiO2thin film suggesting that the improved electrochemical characteristic may be attributed to the inhibition of surface carbonate by ZrO2coating layer.

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Limitations to the use of Sb as a Surfactant During SiGe MBE

MRS Proceedings ◽

10.1557/proc-533-289 ◽

1998 ◽

Vol 533 ◽

Author(s):

Glenn G. Jernigan ◽

Conrad L. Silvestre ◽

Mohammad Fatemi ◽

Mark E. Twigg ◽

Phillip E. Thompson

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Quantum Well ◽

Photoelectron Spectroscopy ◽

Surface Coverage ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Alloy Concentration

AbstractThe use of Sb as a surfactant in suppressing Ge segregation during SiGe alloy growth was investigated as a function of Sb surface coverage, Ge alloy concentration, and alloy thickness using xray photoelectron spectroscopy, x-ray diffraction, and transmission electron microscopy. Unlike previous studies where Sb was found to completely quench Ge segregation into a Si capping layer, we find that Sb can not completely prevent Ge segregation while Si and Ge are being co-deposited. This results in the production of a non-square quantum well with missing Ge at the beginning and extra Ge at the end of the alloy. We also found that Sb does not relieve strain in thin films but does result in compositional or strain variations within thick alloy layers.

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Study by X-ray photoelectron spectroscopy and X-ray diffraction of the growth of TiN thin films obtained by nitridation of Ti layers

Thin Solid Films ◽

10.1016/s0040-6090(96)09126-2 ◽

1996 ◽

Vol 290-291 ◽

pp. 376-380 ◽

Cited By ~ 6

Author(s):

S. Santucci ◽

L. Lozzi ◽

M. Passacantando ◽

P. Picozzi ◽

R. Alfonsetti ◽

...

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

X Ray ◽

Tin Thin Films

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Defect-Related Photoluminescence from SiO2 Thin Films by Si-Ge Ions Doped

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.328-330.1153 ◽

2011 ◽

Vol 328-330 ◽

pp. 1153-1156 ◽

Cited By ~ 1

Author(s):

Kun Zhong ◽

Yan Dong Xia ◽

Ju Hong Miao ◽

Jiang Fu

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Annealing Treatment ◽

X Ray Diffraction ◽

X Ray

Si and Ge ions are implanted into SiO2thin films, subsequently the annealing treatment are carried out. The samples exhibit photoluminescence (PL) peaks at 400, 470, 550 and 780 nm. With the annealing temperature increasing, the intensity of 400-470 nm PL band increases remarkably. After oxidation annealing treatment, the intensity of 400-470 nm PL band decreases, and that of 550 nm and 780 nm PL peaks rises. Combing with the results of X-ray photoelectron spectroscopy(XPS), X-ray diffraction (XRD) and PL measurement, we propose that the PL peaks at 400 nm, 470 nm, 550 nm and 780 nm originate from ≡Ge−Si≡ center, ≡Si−Si≡ center, SPR center and GeO center, respectively.

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Origin of Ultraviolet Luminescence from Bulk ZnO Thin Films Grown by Molecular Beam Epitaxy

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.1.135 ◽

2011 ◽

Vol 1 ◽

pp. 135-139 ◽

Cited By ~ 1

Author(s):

M. Asghar ◽

Khalid Mahmood ◽

Adnan Ali ◽

M.A. Hasan ◽

I. Hussain ◽

...

Keyword(s):

Thin Films ◽

Raman Spectroscopy ◽

Molecular Beam Epitaxy ◽

Room Temperature ◽

Molecular Beam ◽

Energy Dispersive ◽

Zno Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Uv Luminescence

Origin of ultraviolet (UV) luminescence from bulk ZnO has been investigated with the help of photoluminescence (PL) measurements. Thin films of ZnO having 52%, 53% and 54% of Zn-contents were prepared by means of molecular beam epitaxy (MBE). We observed a dominant UV line at 3.28 eV and a visible line centered at 2.5 eV in the PL spectrum performed at room temperature. The intensity of UV line has been found to depend upon the Zn percentage in the ZnO layers. Thereby, we correlate the UV line in our samples with the Zn-interstitials-bound exciton (Zni-X) recombination. The results obtained from, x-ray diffraction, the energy dispersive X-ray spectrum (EDAX) and Raman spectroscopy supported the PL results.

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