Characterization of WO3Thin Films Grown on Silicon by HFMOD

We studied the effect of annealing temperature on the physical properties of WO3thin films using different experimental techniques. WO3has been prepared by hot-filament metal oxide deposition (HFMOD). The films, chemical stoichiometry was determined by X-ray photoelectron spectroscopy (XPS). The monoclinic single-phase nature of the as-deposited films, structure was changed to triclinic structure by annealing them at higher temperatures than 400°C, which has been determined by the X-ray diffraction analysis. By Raman scattering is confirmed the change of crystalline phase, of monoclinic to triclinic, since that lattice vibrational modes of as-deposited WO3and annealed at 500°C present clearly differences. WO3band gap energy can be varied from 2.92 to 3.15 eV by annealing WO3from 0 to 500°C as was obtained by transmittance measurements. The photoluminescence response of the as-deposited film presents three radiative transitions observed at 2.85, 2.41, and 2.04 eV that could be associated with oxygen vacancies; the first one is shifted to higher energies as the annealing temperature is increased due to the change of crystalline phase of the WO3.

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Effects of Thermal Annealing on the Properties of Zirconium-Doped MgxZn1−XO Films Obtained through Radio-Frequency Magnetron Sputtering

Membranes ◽

10.3390/membranes11050373 ◽

2021 ◽

Vol 11 (5) ◽

pp. 373

Author(s):

Wen-Yen Lin ◽

Feng-Tsun Chien ◽

Hsien-Chin Chiu ◽

Jinn-Kong Sheu ◽

Kuang-Po Hsueh

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

Free Electrons ◽

X Ray ◽

Mg Content

Zirconium-doped MgxZn1−xO (Zr-doped MZO) mixed-oxide films were investigated, and the temperature sensitivity of their electric and optical properties was characterized. Zr-doped MZO films were deposited through radio-frequency magnetron sputtering using a 4-inch ZnO/MgO/ZrO2 (75/20/5 wt%) target. Hall measurement, X-ray diffraction (XRD), transmittance, and X-ray photoelectron spectroscopy (XPS) data were obtained. The lowest sheet resistance, highest mobility, and highest concentration were 1.30 × 103 Ω/sq, 4.46 cm2/Vs, and 7.28 × 1019 cm−3, respectively. The XRD spectra of the as-grown and annealed Zr-doped MZO films contained MgxZn1−xO(002) and ZrO2(200) coupled with Mg(OH)2(101) at 34.49°, 34.88°, and 38.017°, respectively. The intensity of the XRD peak near 34.88° decreased with temperature because the films that segregated Zr4+ from ZrO2(200) increased. The absorption edges of the films were at approximately 348 nm under 80% transmittance because of the Mg content. XPS revealed that the amount of Zr4+ increased with the annealing temperature. Zr is a potentially promising double donor, providing up to two extra free electrons per ion when used in place of Zn2+.

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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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Annealing-Driven Microstructural Evolution and Its Effects on the Surface and Nanomechanical Properties of Cu-Doped NiO Thin Films

Coatings ◽

10.3390/coatings9020107 ◽

2019 ◽

Vol 9 (2) ◽

pp. 107 ◽

Cited By ~ 5

Author(s):

San-Ho Wang ◽

Sheng-Rui Jian ◽

Guo-Ju Chen ◽

Huy-Zu Cheng ◽

Jenh-Yih Juang

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Film Surface ◽

X Ray Diffraction ◽

X Ray ◽

Nanomechanical Properties ◽

Glass Substrates ◽

Structural Surface ◽

Diffraction Peaks

The effects of annealing temperature on the structural, surface morphological and nanomechanical properties of Cu-doped (Cu-10 at %) NiO thin films grown on glass substrates by radio-frequency magnetron sputtering are investigated in this study. The X-ray diffraction (XRD) results indicated that the as-deposited Cu-doped NiO (CNO) thin films predominantly consisted of highly defective (200)-oriented grains, as revealed by the broadened diffraction peaks. Progressively increasing the annealing temperature from 300 to 500 °C appeared to drive the films into a more equiaxed polycrystalline structure with enhanced film crystallinity, as manifested by the increased intensities and narrower peak widths of (111), (200) and even (220) diffraction peaks. The changes in the film microstructure appeared to result in significant effects on the surface energy, in particular the wettability of the films as revealed by the X-ray photoelectron spectroscopy and the contact angle of the water droplets on the film surface. The nanoindentation tests further revealed that both the hardness and Young’s modulus of the CNO thin films increased with the annealing temperature, suggesting that the strain state and/or grain boundaries may have played a prominent role in determining the film’s nanomechanical characterizations.

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Effect of Annealing Temperature on Microstructure and Resistivity of TiC Thin Films

Coatings ◽

10.3390/coatings11040457 ◽

2021 ◽

Vol 11 (4) ◽

pp. 457

Author(s):

Litipu Aihaiti ◽

Kamale Tuokedaerhan ◽

Beysen Sadeh ◽

Min Zhang ◽

Xiangqian Shen ◽

...

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

High Vacuum ◽

X Ray Diffraction ◽

X Ray ◽

Good Crystallinity ◽

Different Temperatures ◽

Amorphous States ◽

Spherical Growth

Titanium carbide (TiC) thin films were prepared by non-reactive simultaneous double magnetron sputtering. After deposition, all samples were annealed at different temperatures under high-vacuum conditions. This paper mainly discusses the influence of deposition methods and annealing temperatures on microstructure, surface topography, bonding states and electrical resistivity of TiC films. XRD (X-ray diffraction) results show that TiC thin films can still form crystals without annealing, and the crystallinity of thin films is improved after annealing. The estimated grain size of the TiC films varies from 8.5 nm to 14.7 nm with annealing temperature. It can be seen from SEM (scanning electron microscope) images that surfaces of the films are composed of irregular particles, and when the temperature reaches to 800 °C, the shape of the particles becomes spherical. Growth rate of film is about 30.8 nm/min. Oxygen-related peaks were observed in XPS (X-ray photoelectron spectroscopy) spectra, which is due to the absorption of oxygen atoms on the surface of the film when exposed to air. Raman spectra confirm the formation of TiC crystals and amorphous states of carbon. Resistivity of TiC films decreases monotonically from 666.73 to 86.01 μΩ·cm with the increase in annealing temperature. In brief, the TiC thin films prepared in this study show good crystallinity, thermal stability and low resistivity, which can meet the requirements of metal gate applications.

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Nanostructure and Optical Property Investigations of SrTiO3 Films Deposited by Magnetron Sputtering

Materials ◽

10.3390/ma12010138 ◽

2019 ◽

Vol 12 (1) ◽

pp. 138

Author(s):

Da Xu ◽

Yafei Yuan ◽

Huanfeng Zhu ◽

Ling Cheng ◽

Chunmin Liu ◽

...

Keyword(s):

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Band Gap Energy ◽

Optical Parameters ◽

X Ray Diffraction ◽

X Ray ◽

Lorentz Oscillator ◽

Transmission Electron ◽

Deposited Film ◽

Srtio3 Film

Strontium titanate thin films were deposited on a silicon substrate by radio-frequency magnetron sputtering. The structural and optical properties of these films were characterized by X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry, respectively. After annealing at 600–800 °C, the as-deposited films changed from amorphous to polycrystalline. It was found that an amorphous interfacial layer appeared between the SrTiO3 layer and Si substrate in each as-deposited film, which grew thicker after annealing. The optical parameters of the SrTiO3 film samples were acquired from ellipsometry spectra by fitting with a Lorentz oscillator model. Moreover, we found that the band gap energy of the samples diminished after thermal treatment.

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Biochar as a low-cost, eco-friendly, and electrically conductive material for terahertz applications

Scientific Reports ◽

10.1038/s41598-021-98009-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Woongkyu Park ◽

Hyuntae Kim ◽

Hajung Park ◽

Soobong Choi ◽

Sung Ju Hong ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Low Cost ◽

X Ray Diffraction ◽

Electrically Conductive ◽

X Ray ◽

High Annealing ◽

Structural And Electrical Properties ◽

Terahertz Frequencies ◽

Terahertz Conductivity

AbstractWe investigate conducting characteristics of biochar derived from the pyrolysis of a paper at terahertz frequencies. Paper is annealed under temperatures ranging from 600 to 1000 °C to modify structural and electrical properties. We experimentally observe that the terahertz conductivity increases above 102 S/m as the annealing temperature increases up to 800 °C. From structural characterization using energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, we confirm that more graphitic biochars are produced in high annealing temperature, in agreement with the improvement of terahertz conductivity. Our results show that biochar can be a highly promising candidate to be used in paper-based devices operating at terahertz frequencies.

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Structural and optical characterization of the crystalline phase transformation of electrospinning TiO2 nanofibres by high-temperatures annealing

Revista Mexicana de Física ◽

10.31349/revmexfis.65.459 ◽

2019 ◽

Vol 65 (5 Sept-Oct) ◽

pp. 459

Author(s):

O. Secundino-Sánchez ◽

J. Diaz-Reyes ◽

J. F. Sánchez-Ramírez ◽

And J.L. Jiménez-Pérez

Keyword(s):

Phase Transformation ◽

Raman Scattering ◽

High Temperatures ◽

Crystalline Phase ◽

Annealing Temperature ◽

Crystal Phase ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Range ◽

Wide Range

The electrospinning technique has been used to synthesize TiO2 nanofibres, which by annealing at high temperatures in a wide range achieves the crystal phase transformation of anatase to rutile passing through the anatase+rutile mixed. The investigated temperature range was 0-1000°C. The TiO2 nanofibres chemical stoichiometry and surface morphology were obtained by Scanning Electron Microscopy and Energy Dispersive Spectrometry. The nanofibres diameter was ranged from 137.0 to 115.3 nm in the annealing temperature interval of 0-1000°C. The influence of the annealing temperature on the structure and crystal phase quality of the TiO2crystal has been investigated by X-ray diffraction and Raman scattering. Clear evidence of nanofibres structural transformation from pure anatase to pure rutile structures, including the quasi-amorphous and anatase+rutile mixed phases has been confirmed by Raman scattering. By X-ray diffraction was found that the nanofibres crystalline phases present as preferential growth direction (101) for anatase and (110) for rutile. The Raman spectroscopy exhibits the anomalous behaviour for band broadening and shifting of Raman bands with increasing crystallite size that form the nanofibres. The room-temperature photoluminescence presents radiative bands whose main band redshifts, from 2.56 to 1.32 eV, as the crystalline phase transforms in the investigated annealing temperature range.

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Formation of ZnO films using the SILAR method

Chemija ◽

10.6001/chemija.v30i2.3999 ◽

2019 ◽

Vol 30 (2) ◽

Cited By ~ 1

Author(s):

Birutė Šimkūnaitė-Stanynienė ◽

Giedrė Grincienė ◽

Leonas Naruškevičius ◽

Loreta Tamašauskaitė-Tamašiūnaitė ◽

Algirdas Selskis ◽

...

Keyword(s):

Optical Properties ◽

Photoelectron Spectroscopy ◽

Precursor Solution ◽

Band Gap Energy ◽

Zno Films ◽

X Ray Diffraction ◽

Silar Method ◽

X Ray ◽

Glass Substrates ◽

Layer Adsorption

The thin ZnO films were deposited using the successive ionic layer adsorption and reaction (SILAR) method. The morphology, structure and composition of the thin ZnO films were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The optical properties of the thin ZnO layers, which were deposited onto glass substrates, were investigated using ultraviolet–visible spectrophotometry (UV/Vis). It was found that the optical properties of the ZnO films depend on the composition of anionic precursor solutions, which were used for deposition of the ZnO layers. Moreover, the highest band gap energy of 3.86 eV was obtained for the ZnO layer when the 0.026 mol l–1 Na2B4O7 + 0.002 mol l–1 KMnO4 solution was used as the anionic precursor solution for the deposition of ZnO layers.

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Структура и фотоэлектрические свойства пленок PbSe, осажденных в присутствии аскорбиновой кислоты

Физика и техника полупроводников ◽

10.21883/ftp.2020.10.49935.9411 ◽

2020 ◽

Vol 54 (10) ◽

pp. 1004

Author(s):

Л.Н. Маскаева ◽

В.М. Юрк ◽

В.Ф. Марков ◽

М.В. Кузнецов ◽

В.И. Bоронин ◽

...

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

X Ray Diffraction ◽

Ir Detectors ◽

X Ray ◽

Optical Band Gaps ◽

Photoelectric Properties ◽

Highly Sensitive ◽

Deposited Films

PbSe thin films chemically deposited using ascorbic acid as an antioxidant for selenourea were examined by X -ray diffraction (XRD), scanning electron microscopy (SEM) with X -ray microanalysis (EDX) and X -ray photoelectron spectroscopy (XPS). Influence of annealing temperature on chemical and phase composition, lattice parameters, surface morphology and photoelectric properties were studied. Determined that PbSe thin films contain dopant phase PbSeO3, PbSeO4, PbI2 after annealing at 633−683K. The direct and indirect optical band gaps Eg layers were observed. It has been shown that the deposited films are comparable with known commercial samples by their threshold photoelectric characteristics and can be used to create highly sensitive IR detectors.

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Hot Filament Assisted CVD of Titanium Nitride Films

MRS Proceedings ◽

10.1557/proc-327-115 ◽

1993 ◽

Vol 327 ◽

Cited By ~ 1

Author(s):

Sadanand V. Deshpande ◽

Erdogan Gulari

Keyword(s):

Thin Films ◽

Titanium Nitride ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

X Ray Diffraction ◽

Titanium Chloride ◽

X Ray ◽

Aluminum Metallization ◽

Temperature Deposition ◽

Hot Filament

AbstractTitanium nitride thin films have been deposited using a novel Hot Filament Chemical Vapor Deposition (HFCVD) technique. In this technique, a resistively heated tungsten wire (∼1700°C) is used to decompose ammonia to obtain highly reactive nitrogen precursor species. This approach allows for low temperature deposition of nitride thin films. In the past, we have used this method to deposit good quality silicon and aluminum nitride films. Titanium nitride thin films have been deposited on Si(100) at substrate temperatures from 500°C to 600°C. These films were characterized using X-ray photoelectron spectroscopy (XPS), X-ray diffraction, Rutherford backscattering spectroscopy (RBS) and scanning electron microscopy. The effects of deposition pressure, substrate temperature and titanium chloride flow rate on film properties have been studied. TiN films with resistivities as low as 80.0 μΩ-cm have been deposited. RBS analysis indicates that the films serve as excellent diffusion barriers for copper and aluminum metallization on silicon.

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