Correlation between Oxygen Related Bonds and Defects Formation in ZnO Thin Films by Using X-ray Diffraction and X-ray Photoelectron Spectroscopy

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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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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Resistive Switching Characteristics of Li-Doped ZnO Thin Films Based on Magnetron Sputtering

Materials ◽

10.3390/ma12081282 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1282 ◽

Cited By ~ 8

Author(s):

Zhao ◽

Li ◽

Ai ◽

Wen

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Resistive Switching ◽

Photoelectron Spectroscopy ◽

Lattice Structure ◽

Zno Thin Films ◽

Bipolar Resistive Switching ◽

X Ray ◽

Doped Zno ◽

Switching Characteristics

A kind of devices Pt/Ag/ZnO:Li/Pt/Ti with high resistive switching behaviors were prepared on a SiO2/Si substrate by using magnetron sputtering method and mask technology, composed of a bottom electrode (BE) of Pt/Ti, a resistive switching layer of ZnO:Li thin film and a top electrode (TE) of Pt/Ag. To determine the crystal lattice structure and the Li-doped concentration in the resulted ZnO thin films, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) tests were carried out. Resistive switching behaviors of the devices with different thicknesses of Li-doped ZnO thin films were studied at different set and reset voltages based on analog and digital resistive switching characteristics. At room temperature, the fabricated devices represent stable bipolar resistive switching behaviors with a low set voltage, a high switching current ratio and a long retention up to 104 s. In addition, the device can sustain an excellent endurance more than 103 cycles at an applied pulse voltage. The mechanism on how the thicknesses of the Li-doped ZnO thin films affect the resistive switching behaviors was investigated by installing conduction mechanism models. This study provides a new strategy for fabricating the resistive random access memory (ReRAM) device used in practice.

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Comparative Study of ZnO Thin Films Grown on Quartz Glass and Sapphire (001) Substrates by Means of Magnetron Sputtering and High-Temperature Annealing

Applied Sciences ◽

10.3390/app9214509 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4509

Author(s):

Weijia Yang ◽

Fengming Wang ◽

Zeyi Guan ◽

Pengyu He ◽

Zhihao Liu ◽

...

Keyword(s):

Thin Films ◽

High Temperature ◽

Magnetron Sputtering ◽

Comparative Study ◽

Quartz Glass ◽

Photoelectron Spectroscopy ◽

Zno Thin Films ◽

High Temperature Annealing ◽

X Ray ◽

Glass Substrates

In this work, we reported a comparative study of ZnO thin films grown on quartz glass and sapphire (001) substrates through magnetron sputtering and high-temperature annealing. Firstly, the ZnO thin films were deposited on the quartz glass and sapphire (001) substrates in the same conditions by magnetron sputtering. Afterwards, the sputtered ZnO thin films underwent an annealing process at 600 °C for 1 h in an air atmosphere to improve the quality of the films. X-ray diffraction, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectra, photoluminescence spectra, and Raman spectra were used to investigate the structural, morphological, electrical, and optical properties of the both as-received ZnO thin films. The ZnO thin films grown on the quartz glass substrates possess a full width of half maximum value of 0.271° for the (002) plane, a surface root mean square value of 0.50 nm and O vacancies/defects of 4.40% in the total XPS O 1s peak. The comparative investigation reveals that the whole properties of the ZnO thin films grown on the quartz glass substrates are comparable to those grown on the sapphire (001) substrates. Consequently, ZnO thin films with high quality grown on the quartz glass substrates can be achieved by means of magnetron sputtering and high-temperature annealing at 600 °C.

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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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Effect of Flexible Substrates on the Structural and Optical Properties of ZnO Films Deposited by Sputtering Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1107.678 ◽

2015 ◽

Vol 1107 ◽

pp. 678-683 ◽

Cited By ~ 2

Author(s):

Lam Mui Li ◽

Azmizam Manie Mani ◽

Saafie Salleh ◽

Afishah Alias

Keyword(s):

Thin Films ◽

Band Gap ◽

Low Cost ◽

Argon Plasma ◽

Optical Transmittance ◽

Zno Thin Films ◽

Plastic Substrate ◽

Zno Films ◽

X Ray Diffraction ◽

X Ray

Zinc Oxide (ZnO) has attracted much attention because of its high optical transmittance approximately ~80 % with a wide band gap of (3.3 eV at 300 K) and a relatively low cost material. ZnO thin films were deposited on plastic substrate using RF powered magnetron sputtering method. The target used is ZnO disk with 99.99 % purity. The sputtering processes are carried out with argon gas that flow from 10-15 sccm. Argon is used to sputter the ZnO target because the ability of argon that can remove ZnO layer effectively by sputtering with argon plasma bombardment. The deposited ZnO thin films are characterized using X-Ray Diffraction (XRD) and UV-Vis Spectrometer. The analysis of X-ray diffraction show that good crystalline quality occurs at nominal thickness of 400 nm. The optical studies showed that all the thin films have high average transmittance of approximately 80 % and the estimated value of optical band gap is within 3.1 eV-3.3 eV range.

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X-ray diffraction analysis of residual stresses in textured ZnO thin films

Applied Surface Science ◽

10.1016/j.apsusc.2016.06.060 ◽

2017 ◽

Vol 395 ◽

pp. 16-23 ◽

Cited By ~ 11

Author(s):

E. Dobročka ◽

P. Novák ◽

D. Búc ◽

L. Harmatha ◽

J. Murín

Keyword(s):

Thin Films ◽

Residual Stresses ◽

Diffraction Analysis ◽

Zno Thin Films ◽

X Ray Diffraction ◽

X Ray

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Electron carrier concentration dependent magnetization in ZnO:Co and ZnO:Mn thin films

MRS Proceedings ◽

10.1557/proc-1035-l06-06 ◽

2007 ◽

Vol 1035 ◽

Author(s):

Zheng Yang ◽

Maurizio Biasini ◽

Leelaprasanna J Mandalapu ◽

Zheng Zuo ◽

Ward P Beyermann ◽

...

Keyword(s):

Thin Films ◽

Carrier Concentration ◽

Concentration Dependence ◽

Long Range ◽

Room Temperature ◽

Zno Thin Films ◽

X Ray Diffraction ◽

Electron Carrier ◽

X Ray ◽

Curie Temperatures

AbstractCo and Mn ions were implanted into n-type ZnO thin films with different electron carrier concentrations. X-ray diffraction measurements show that the ZnO:Co and ZnO:Mn thin films are of high crystallinity. From magnetization measurements, ferromagnetism was observed in both n-type ZnO:Co and n-type ZnO:Mn thin films with Curie temperatures well-above room temperature. Furthermore, the electron carrier concentration dependence of the saturated magnetization was measured in both types of thin films, and our results support an electron-mediated mechanism for ferromagnetism in ZnO:Co, as predicted by theory. However, our measurements seem to contradict theory for ZnO:Mn, which only predicts long-range ferromagnetism for p-type mediated material.

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