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دسترسی آزاد مقاله
1 - Modifying and adjusting features of ZnO-based UV sensors through singly- and co-doping with Ti and Zr using low current sputtering technique
Nader Madani-Mashaei Ebrahim Asl Soleimani Hamidreza Shirvani-MahdaviThe possibility of modifying and adjusting the properties of ZnO-based sensors in the post-fabrication stage is demonstrated by singly- and co-sputtering of ZnO thin films with zirconium and titanium nanoparticles. First, thin films of zinc oxide are created on glass su چکیده کاملThe possibility of modifying and adjusting the properties of ZnO-based sensors in the post-fabrication stage is demonstrated by singly- and co-sputtering of ZnO thin films with zirconium and titanium nanoparticles. First, thin films of zinc oxide are created on glass substrates by sol-gel process and spin coating, and some of these films are converted to UV sensors through electrode placement on them by thermal evaporation method. Then, a number of the initial detectors are singly- and co-doped with Ti and Zr using sputtering deposition technique. Experiments show that the modification and adjustment of the parameters of the sensors through low current sputtering technique (LCST) is possible more efficiently and controllably. The transient response of all sensors are measured using I-t tests with periodic UV illumination before and after sputtering. Comparison of the results before and after doping shows that the photoresponsivity is improved on all doped sensors, and in many cases, a simultaneous improvement in this quantity and rise time is observed. In the best-case scenario, relative to undoped sensors, the photoresponsivity of the sensors doped with zirconium increases by more than 429 times, while the rise time of the sensors co-doped with titanium and zirconium decreases to less than 50%. This experience indicates that the modification and adjustment of the properties of ZnO-based sensors and actuators after electrode placement, to a large extent, is possible through LCST. It is noteworthy that this can be performed depending on the need and selectively in the shortest time, at the lowest cost. پرونده مقاله -
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2 - Optical imaging and magnetic field simulation of a DC circular planar magnetron sputtering discharge
Ahmad Rastkar Ali Reza Niknam Mostafa SalahshoorIn this paper, the optical images of glow discharge plasma and the finite element method simulation of the magnetic field strength in a balanced and two types of unbalanced DC circular planar magnetron sputtering sources are presented. The investigation showed that wher چکیده کاملIn this paper, the optical images of glow discharge plasma and the finite element method simulation of the magnetic field strength in a balanced and two types of unbalanced DC circular planar magnetron sputtering sources are presented. The investigation showed that wherever the magnetic field strength is stronger, the intensity of light and the ionization are greater and consequently, the deposition is higher. The comparison of recorded optical images with the finite element simulation results of the magnetic field strength indicated the correlation between regions of high magnetic field strength and high light emission. پرونده مقاله -
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3 - Chromium thin film deposition on ITO substrate by RF sputtering
Elaheh Akbarnejad Ebrahim Asl Soleimani Zohreh GhorannevisAbstractTo obtain a suitable ohmic contact with the lowest resistivity, chromium (Cr) thin films were deposited on transparent conductive oxide indium tin oxide (ITO) by RF sputtering method in argon atmosphere and its electrical properties were optimized. The depositio چکیده کاملAbstractTo obtain a suitable ohmic contact with the lowest resistivity, chromium (Cr) thin films were deposited on transparent conductive oxide indium tin oxide (ITO) by RF sputtering method in argon atmosphere and its electrical properties were optimized. The deposition of Cr thin film has been performed for the layers with thickness of 150, 300 and 600 nm in constant Ar gas flow of 30 SCCM. Results show that the lowest contact resistivity belongs to the layer with 600 nm thickness. Furthermore, Cr/ITO has been studied for five different RF powers of 100, 150, 200, 250 and 300 W. Experimental results show that specific contact resistance of Cr/ITO contact decreases in condition of depositing chromium thin films on ITO at higher RF powers. Analysis of SEM has been performed on the samples. The SEM micrographs show Cr thin films have smaller grains at RF power of 150 W, in comparison with other RF powers. The lowest specific contact resistivity for Cr/ITO has been obtained 4.7 × 10−2 Ω cm2 at RF power of 150 W with 600 nm thickness of chromium thin films. پرونده مقاله -
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4 - Role of substrate and deposition conditions on the texture evolution of titanium nitride thin film on bare and plasma-nitrided high-speed steel
Partha Saikia Alphonsa Joseph Ramakrishna Rane Bipul Kumar Saikia Subroto MukherjeeAbstractTitanium nitride (TiN) films are prepared by direct current (DC) magnetron sputtering of a titanium (Ti) target in an argon (Ar) + nitrogen (N2) atmosphere on bare and pulsed DC plasma-nitrided high-speed steel (AISI M2) substrate. One set of coating is deposite چکیده کاملAbstractTitanium nitride (TiN) films are prepared by direct current (DC) magnetron sputtering of a titanium (Ti) target in an argon (Ar) + nitrogen (N2) atmosphere on bare and pulsed DC plasma-nitrided high-speed steel (AISI M2) substrate. One set of coating is deposited using different N2 partial pressures keeping the working pressure fixed, and it leads to variable film thickness. Another set of coating of equal thickness is prepared at the same working pressure with variable substrate biasing voltage. The detailed structure of the coatings is analyzed by X-ray diffraction study. The texture coefficient (Tc) determined from X-ray diffraction studies at various deposition conditions gives information about crystallographic orientation. It is found that the same deposition condition leads to different orientation of TiN coatings on bare AISI M2 and plasma-nitrided AISI M2 substrate. The results are discussed in terms of energy minimization and substrate-induced preferred orientation. پرونده مقاله -
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5 - Growth of europium-doped gallium oxide (Ga2O3:Eu) thin films deposited by homemade DC magnetron sputtering
Putut Marwoto Sugianto Sugianto Edy WibowoAbstractEuropium-doped gallium oxide (Ga2O3:Eu) thin films have successfully been grown using direct current magnetron sputtering by means of Eu concentration variation. Energy-dispersive X-ray spectroscopy spectra indicate gallium, oxygen, and europium elements as the چکیده کاملAbstractEuropium-doped gallium oxide (Ga2O3:Eu) thin films have successfully been grown using direct current magnetron sputtering by means of Eu concentration variation. Energy-dispersive X-ray spectroscopy spectra indicate gallium, oxygen, and europium elements as the growing films' chemical compositions. Based on scanning electron microscopy images, the morphology of Ga2O3:Eu thin film is seemingly like a granulated nano-size configuration. In this study, UV-visible spectrophotometer results show that the variation of Eu doping concentration inflicted no change toward the optical bandgap of the growing films. The optical bandgaps of undoped Ga2O3 film and Ga2O3:Eu film were seen to be relatively similar, i.e., approximately 3.4 eV. Yet, the presence of Eu doping in Ga2O3 configuration had led to blueshift phenomenon when the concentration was 2% and redshift phenomenon when it was 5%. Photoluminescence emissions of all samples were observed in the red area with the emission peak between 593 and 602 nm. پرونده مقاله -
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6 - Optical characterization of Cu3N thin film with Swanepoel method
Davoud Dorranian Laya Dejam Gelareh MosayebianAbstractSwanepoel method is employed for spectroscopic determination of optical properties of Cu3N thin film using transmittance data. Investigated films have been deposited using reactive magnetron sputtering system. Deposition time was 9 to 21 min. Refractive index, a چکیده کاملAbstractSwanepoel method is employed for spectroscopic determination of optical properties of Cu3N thin film using transmittance data. Investigated films have been deposited using reactive magnetron sputtering system. Deposition time was 9 to 21 min. Refractive index, absorption coefficient, and bandgap energy of the samples are determined. Thickness of the films is calculated by Swanepoel method, and result is compared with the thickness of the films measured by profilmeter. It is shown that Swanepoel method is a reliable way to calculate the optical constants of thin films when the transmittance spectrum of the film is influenced by wavelike patterns due to reflection of the probe beam from different interfaces. پرونده مقاله -
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7 - Effect of silver thickness on structural, optical and morphological properties of nanocrystalline Ag/NiO thin films
S. Jalili F. Hajakbari A. HojabriAbstractSilver (Ag) nanolayers were deposited on nickel oxide (NiO) thin films by DC magnetron sputtering. The thickness of Ag layers was in range of 20–80 nm by variation of deposition time between 10 and 40 s. X-ray diffraction results showed that the crystalline prop چکیده کاملAbstractSilver (Ag) nanolayers were deposited on nickel oxide (NiO) thin films by DC magnetron sputtering. The thickness of Ag layers was in range of 20–80 nm by variation of deposition time between 10 and 40 s. X-ray diffraction results showed that the crystalline properties of the Ag/NiO films improved by increasing the Ag film thickness. Also, atomic force microscopy and field emission scanning electron microscopy images demonstrated that the surface morphology of the films was highly affected by film thickness. The film thickness and the size of particles change by elevating the Ag deposition times. The composition of films was determined by Rutherford back scattering spectroscopy. The transmission of light was gradually reduced by augmentation of Ag films thickness. Furthermore; the optical band gap of the films was also calculated from the transmittance spectra. پرونده مقاله -
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8 - Effect of substrate temperature on structural, morphological and optical properties of deposited Al/ZnO films
Z. Ghorannevis M. T. Hosseinnejad M. Habibi P. GolmahdiAbstractAl-doped ZnO (Al/ZnO) thin film is a promising alternative to an ITO electrode in solar cell applications due to its low price, non-toxicity and other promising properties. In this paper, Al/ZnO thin films at different substrate temperatures were deposited on gl چکیده کاملAbstractAl-doped ZnO (Al/ZnO) thin film is a promising alternative to an ITO electrode in solar cell applications due to its low price, non-toxicity and other promising properties. In this paper, Al/ZnO thin films at different substrate temperatures were deposited on glass substrates as transparent conducting (TCO) films by DC magnetron sputtering. The effect of substrate temperature on the structural, morphological and optical properties of Al/ZnO films was investigated. X-ray diffraction (XRD) analysis suggests that crystal structure characteristics of synthesized thin films depend on the substrate temperature. The structure growth and variation in surface roughness with increasing substrate temperature are revealed by scanning electron microscope (SEM) micrographs and atomic force microscopy (AFM) analyses. Thicknesses of the deposited films were also examined by surface profiler. Moreover, obtained results from optical transmission patterns revealed that with the increasing substrate temperature, optical transmittance decreases. پرونده مقاله -
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9 - Investigation of annealing temperature effect on magnetron sputtered cadmium sulfide thin film properties
E. Akbarnejad Z. Ghorannevis F. Abbasi M. GhorannevissAbstractCadmium sulfide (CdS) thin films are deposited on the fluorine doped tin oxide coated glass substrate using the radio frequency magnetron sputtering setup. The effects of annealing in air on the structural, morphological, and optical properties of CdS thin film چکیده کاملAbstractCadmium sulfide (CdS) thin films are deposited on the fluorine doped tin oxide coated glass substrate using the radio frequency magnetron sputtering setup. The effects of annealing in air on the structural, morphological, and optical properties of CdS thin film are studied. Optimal annealing temperature is investigated by annealing the CdS thin film at different annealing temperatures of 300, 400, and 500 °C. Thin films of CdS are characterized by X-ray diffractometer analysis, field emission scanning electron microscopy, atomic force microscopy, UV–Vis–NIR spectrophotometer and four point probe. The as-grown CdS films are found to be polycrystalline in nature with a mixture of cubic and hexagonal phases. By increasing the annealing temperature to 500 °C, CdS film showed cubic phase, indicating the phase transition of CdS. It is found from physical characterizations that the heat treatment in air increased the mean grain size, the transmission, and the surface roughness of the CdS thin film, which are desired to the application in solar cells as a window layer material. پرونده مقاله -
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10 - The texture ordering in L10-FePt–Ag nanocomposites
R. Roghani S. A. Sebt A. KhajehnezhadAbstractL10-FePt nanoparticles with different Ag percentages were prepared. The presence of 6% Ag in co-sputtering process with deposition rate of 1 A˙/sdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepack چکیده کاملAbstractL10-FePt nanoparticles with different Ag percentages were prepared. The presence of 6% Ag in co-sputtering process with deposition rate of 1 A˙/sdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ {dot{A}}/ ext{s} $$end{document} at 500 °C led to the formation of FePt nanoparticles with 5–7 nm size in L10-fct phase. Moreover, Ag atoms laying in boundaries of these nanoparticles in these circumstances caused c axis to orient and (001) peak intensity in XRD spectrum to increase. This is the result of the indirect exchange interactions of Fe magnetic atoms through Ag atoms in these boundaries. Therefore, where L10-FePt grains have the most boundaries with each other, the order index would be maximum. پرونده مقاله -
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11 - Effect of rapid thermal annealing on structural and optical properties of ZnS thin films fabricated by RF magnetron sputtering technique
M. S. Bashar Rummana Matin Munira Sultana Ayesha Siddika M. Rahaman M. A. Gafur F. AhmedAbstractThe ZnS thin films have been deposited by radio frequency magnetron sputtering at room temperature. Post-deposition rapid thermal annealing treatment was done for the films deposited at different powers ranging from 70 to 100 W. One peak is observed for as-depos چکیده کاملAbstractThe ZnS thin films have been deposited by radio frequency magnetron sputtering at room temperature. Post-deposition rapid thermal annealing treatment was done for the films deposited at different powers ranging from 70 to 100 W. One peak is observed for as-deposited and annealed thin films at around 28.48° corresponding to the (111) reflection plane indicating a zincblende structure. The overall intensity of the peaks and the FWHM values of as-deposited films increased after annealing corresponding to the increase in crystallinity. The optical energy bandgap is found in the range of 3.24–3.32 eV. With increasing annealing temperature, the decrease in the Urbach energy values indicating a decrease in localized states which is in good agreement with the XRD results where the crystallinity increased. The surface morphology of the films seems to be composed of Nano-granules with a compact arrangement. Apparently, the grain size increases in the deposited films as annealing temperature increases. The compositional ratio attained close to the stoichiometric ratio of 1:1 after annealing. From the Hall effect measurement, the carrier concentration and mobility are found to increase after annealing. The high carrier concentration and mobility also comply with structural and optical analysis. Best results are found for the film annealed at 400 °C deposited at 90 W. پرونده مقاله -
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12 - Comparing the structural and magnetic properties of FePt/MgO/Si and FePt/Ag/Si granular nanolayers
M. Sheikhi S. A. Sebt A. KhajehnezhadAbstractThe properties of L10-FePt nanoparticles can be improved in the presence of MgO and Ag interlayers in direct sputtering and annealing method, respectively. Such properties are crystal and compound ordering, nanostructure and crystal orientation. In this work, Fe چکیده کاملAbstractThe properties of L10-FePt nanoparticles can be improved in the presence of MgO and Ag interlayers in direct sputtering and annealing method, respectively. Such properties are crystal and compound ordering, nanostructure and crystal orientation. In this work, FePt nanoparticles in ferromagnetic L10-fct phase were synthesized using sputtering method on Ag and MgO layers. According to XRD analyses, the impact of the presence of these two kinds of interlayer on crystal structure and its orientation has been investigated. Furthermore, the effect of the presence of 10% Ag on these properties has been studied and their granular layer nanostructures were characterized through the FE-SEM analysis. The results show that the presence of Ag as nanocompound and interlayer is desirable on declining the transition temperature and controlling the size during annealing. The presence of MgO as a sublayer in direct synthesis leads to the formation of 10 nm monosize smaller nanoparticles. According to VSM analysis, MgO and Ag sublayers have increased the magnetic coercivity of the FePt nanoparticles by 3.4 times and 3.7 times, respectively. پرونده مقاله -
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13 - The effect of varying temperature and O2 flow rate in ex situ annealed tin-doped indium for fabrication of commercial grade indium tin oxide
M. R. Kiyani Y. S. JaliliAbstractIn this work, tin-doped indium was deposited on a glass substrate via the electron beam evaporation technique. Then, the as-grown thin films were baked in the presence of oxygen at different O2 flow rates and temperatures inside a furnace to obtain transparent c چکیده کاملAbstractIn this work, tin-doped indium was deposited on a glass substrate via the electron beam evaporation technique. Then, the as-grown thin films were baked in the presence of oxygen at different O2 flow rates and temperatures inside a furnace to obtain transparent conducting oxide thin film structures. The electrical and optical properties of the layers were investigated, the thickness of all samples was kept at 500 nm and the rate of deposition was set at 0.1 nm min−1. The best optical and electrical properties were obtained at O2 flow rate of 1.5 Nl min−1 and temperatures of 500 °C where above 90 % optical transparency and ≤4 × 10−3ohm cm−1 electrical resistivity were achieved. پرونده مقاله -
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14 - Structural and optical characterization of ZrO2 thin films grown on silicon and quartz substrates
Alireza HojabriAbstractZirconium oxide thin films were grown successfully by thermal annealing of zirconium thin films deposited on quartz and silicon substrates by direct current magnetron sputtering technique. The structural and optical properties in relation to thermal annealing ti چکیده کاملAbstractZirconium oxide thin films were grown successfully by thermal annealing of zirconium thin films deposited on quartz and silicon substrates by direct current magnetron sputtering technique. The structural and optical properties in relation to thermal annealing times were investigated. The X-ray diffraction patterns revealed that structure of films changes from amorphous to crystalline by increase of annealing times in range 60–240 min. The composition of films was determined by Rutherford back scattering spectroscopy. Atomic force microscopy results exhibited that surface morphology and roughness of films depend on the annealing time. The refractive index of the films was calculated using Swanepoel’s method. The optical band gap energy of annealed films decreased from 5.50 to 5.34 eV with increasing thermal annealing time. پرونده مقاله -
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15 - Effects of various deposition times and RF powers on CdTe thin film growth using magnetron sputtering
Z. Ghorannevis E. Akbarnejad M. GhorannevissAbstractCadmium telluride (CdTe) is a p-type II-VI compound semiconductor, which is an active component for producing photovoltaic solar cells in the form of thin films, due to its desirable physical properties. In this study, CdTe film was deposited using the radio fre چکیده کاملAbstractCadmium telluride (CdTe) is a p-type II-VI compound semiconductor, which is an active component for producing photovoltaic solar cells in the form of thin films, due to its desirable physical properties. In this study, CdTe film was deposited using the radio frequency (RF) magnetron sputtering system onto a glass substrate. To improve the properties of the CdTe film, effects of two experimental parameters of deposition time and RF power were investigated on the physical properties of the CdTe films. X-ray Diffraction (XRD), atomic force microscopy (AFM) and spectrophotometer were used to study the structural, morphological and optical properties of the CdTe samples grown at different experimental conditions, respectively. Our results suggest that film properties strongly depend on the experimental parameters and by optimizing these parameters, it is possible to tune the desired structural, morphological and optical properties. From XRD data, it is found that increasing the deposition time and RF power leads to increasing the crystallinity as well as the crystal sizes of the grown film, and all the films represent zinc blende cubic structure. Roughness values given from AFM images suggest increasing the roughness of the CdTe films by increasing the RF power and deposition times. Finally, optical investigations reveal increasing the film band gaps by increasing the RF power and the deposition time. پرونده مقاله -
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16 - Role of Ar/O2 mixture on structural, compositional and optical properties of thin copper oxide films deposited by DC magnetron sputtering
N. Aghilizadeh A. H. Sari D. DorranianAbstractIn this study, the effect of oxygen content on a thin copper oxide layer deposited on BK7 and steel substrates by DC magnetron sputtering were investigated. Argon as working gas with impurity of 99.9% and various oxygen ratios were used to sputter a pure Cu cath چکیده کاملAbstractIn this study, the effect of oxygen content on a thin copper oxide layer deposited on BK7 and steel substrates by DC magnetron sputtering were investigated. Argon as working gas with impurity of 99.9% and various oxygen ratios were used to sputter a pure Cu cathode target in a cylindrical geometry. The produced samples were analyzed by X-ray diffraction (XRD), energy-dispersive X-ray (EDX), atomic force microscopy (AFM), and spectrophotometry techniques. The films thickness was measured by profilometer facility. The results show that by increasing oxygen content in the working gas the sputtering rate reduces. Moreover, the type of oxide phase (Cu2O or CuO) in the synthesized layer and consequently its optical properties dramatically depend on Ar/O2 ratio in the working gas. پرونده مقاله -
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17 - Structural and morphological properties of ITO thin films grown by magnetron sputtering
Z. Ghorannevis E. Akbarnejad M. GhorannevissAbstractPhysical properties of transparent and conducting indium tin oxide (ITO) thin films grown by radiofrequency (RF) magnetron sputtering are studied systematically by changing deposition time. The X-ray diffraction (XRD) data indicate polycrystalline thin films wit چکیده کاملAbstractPhysical properties of transparent and conducting indium tin oxide (ITO) thin films grown by radiofrequency (RF) magnetron sputtering are studied systematically by changing deposition time. The X-ray diffraction (XRD) data indicate polycrystalline thin films with grain orientations predominantly along the (2 2 2) and (4 0 0) directions. From atomic force microscopy (AFM) it is found that by increasing the deposition time, the roughness of the film increases. Scanning electron microscopy (SEM) images show a network of a high-porosity interconnected nanoparticles, which approximately have a pore size ranging between 20 and 30 nm. Optical measurements suggest an average transmission of 80 % for the ITO films. Sheet resistances are investigated using four-point probes, which imply that by increasing the film thickness the resistivities of the films decrease to 2.43 × 10−5 Ω cm. پرونده مقاله -
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18 - Capacitive properties of zinc oxide thin films by radiofrequency magnetron sputtering
Roger Ondo-Ndong Hans Essone-Obame Zita Hermance Moussambi Nathaniel KoumbaAbstractThe study focused on the production of zinc oxide (ZnO) thin films as a dielectric material for use in metal–insulator–semiconductor capacitors. The objective of this study has demonstrated the frequency dependence of conductivity and capacity. Zinc oxide (ZnO) چکیده کاملAbstractThe study focused on the production of zinc oxide (ZnO) thin films as a dielectric material for use in metal–insulator–semiconductor capacitors. The objective of this study has demonstrated the frequency dependence of conductivity and capacity. Zinc oxide (ZnO) was thin films deposited by a silicon wavelength sputteringmagnetron cathode sputtering. The capacitive properties of ZnO zinc oxide were studied at room temperature. The frequency dependence of the conductivity, capacitance and the measured current–voltage (I–V) characteristics of ZnO zinc oxide thin films were studied in the frequency range from 5 kHz to 13 MHz. It is shown that the conductivity is total. Indeed, the measurement of the conductivity in alternating regime obeys the Arrhenius equation. In addition, the measured I–V characteristics of the structures studied at 10 kHz and 10 MHz clearly revealed areas of accumulation, depletion and inversion in the plots. It has been observed that AC conductivity and capacity in the ZnO thin films (ZnO) are frequency dependent. This dependence indicates that the conduction is thermally activated and maintains the correlated barrier of the charge carrier on the localized states as a function of the experimental data. The FBAR (expand) devices with the ZnO films exhibited a pronounced resonance peak centered at 537 MHz with a k2 coupling coefficient of 7%. It found therefore that the impedance matching of the FBAR could be easily achieved simply by controlling the resonance the resonator. پرونده مقاله -
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19 - Effect of plasma oxidation parameters on physical properties of nanocrystalline nickel oxide thin films grown by two-step method: DC sputtering and plasma oxidation
F. Hajakbari S. Rashvand A. HojabriAbstractNanocrystalline nickel oxide (NiO) thin films were successfully grown on quartz substrates by two-step method. In the first step, nickel films were deposited on quartz substrates by DC magnetron sputtering technique. Then, the plasma oxidation of nickel films wa چکیده کاملAbstractNanocrystalline nickel oxide (NiO) thin films were successfully grown on quartz substrates by two-step method. In the first step, nickel films were deposited on quartz substrates by DC magnetron sputtering technique. Then, the plasma oxidation of nickel films was used for preparation of nickel oxide. The effect of DC plasma power and treatment time on the structural, morphological and optical properties of the NiO films were investigated by different analyses. XRD results indicated that the plasma powers effectively influenced the structure of films, and the best crystallinity was obtained for plasma power of 15 w and treatment time of 20 min. The XPS, RBS and EDS analysis confirmed the presence of Ni and O elements. The FESEM and AFM images showed a granular structure with spherical shapes of grains. The optical band gap of the films synthesized under different plasma oxidation conditions was also discussed. پرونده مقاله -
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20 - Influence of O2 and N2 Concentrations on the Characteristics of Plasma in DC Cylindrical Magnetron Discharge by Langmuir Probe
Kiomars Yasserian Zahra KarimiUsing the Langmuir probe method, the reactive plasma parameters were studied in different ratios of oxygen and nitrogen concentrations in a DC cylindrical discharge device.The plasma parameters such as plasma potential, electron density and electron temperature weree چکیده کاملUsing the Langmuir probe method, the reactive plasma parameters were studied in different ratios of oxygen and nitrogen concentrations in a DC cylindrical discharge device.The plasma parameters such as plasma potential, electron density and electron temperature wereextracted from the current-voltage characteristic’s curve of Langmuir probe to find the optimum conditions for deposit the oxynitride thin films.Chromium thin films were exposed to various O2/N2 partial pressures to obtain optimum valuefor produce of oxynitride chrome thin films. In addition, the influence of the magnetic field on the structural properties of the chrome oxynitride thin films was obtained. It is observed that for equal percentage of reactive gases, the optimum condition of the plasma discharge takes place in which the crystalline phases of oxynitride chrome thin films appear. پرونده مقاله -
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21 - Effect of Thickness on Structural and Morphological Properties of AlN Films Prepared Using Single Ion Beam Sputtering
Fatemeh Hajakbari Alireza Hojabri Majid Mojtahedzadeh LarijaniAluminum nitride (AlN) thin films have potential applications in microelectronic and optoelectronic devices. In this study, AlN thin films with different thicknesses were deposited on silicon substrate by single ion beam sputtering method. The X-ray diffraction (XRD) sp چکیده کاملAluminum nitride (AlN) thin films have potential applications in microelectronic and optoelectronic devices. In this study, AlN thin films with different thicknesses were deposited on silicon substrate by single ion beam sputtering method. The X-ray diffraction (XRD) spectra revealed that the structure of films with thickness of - nm was amorphous, while the polycrystalline hexagonal AlN with a rough surface was observed at a thickness of nm. Also, the formation of AlN in amorphous films is identified by Fourier transform infrared (FTIR) spectroscopy. Atomic force microscopy (AFM) study confirms that the surface roughness and average grain size of films increased with film thickness. پرونده مقاله -
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22 - Preparation and Characterization of Aluminum Nitride Thin Films with the Potential Application in Electro-Acoustic Devices
Fatemeh HajakbariIn this work, aluminum nitride (AlN) thin films with different thicknesses were deposited on quartz and silicon substrates using single ion beam sputtering technique. The physical and chemical properties of prepared films were investigated by different characterization چکیده کاملIn this work, aluminum nitride (AlN) thin films with different thicknesses were deposited on quartz and silicon substrates using single ion beam sputtering technique. The physical and chemical properties of prepared films were investigated by different characterization technique. X-ray diffraction (XRD) spectra revealed that all of the deposited films have an amorphous structure. The Al-N bond information of deposited films on silicon substrates was identified by Fourier transform infrared (FTIR) spectroscopy. FTIR results confirmed the formation of AlN films in prepared samples. Atomic force microscopy (AFM) revealed that the surface of films was smooth with low values of roughness. The low values of roughness can be caused the low acoustic loss in AlN films, which is interesting for applications in electro-acoustic devices. پرونده مقاله -
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23 - Investigation of Structural, Morphological and Optical Properties of Chromium Oxide Thin Films Prepared at Different Annealing Times
Fatemeh Hajakbari Alireza HojabriChromium oxide (α-Cr2O3) thin films were prepared using thermal annealing of chromium (Cr)films deposited on quartz substrates by direct current (DC) magnetron sputtering. The annealingprocess of the films was performed for different times of 60, 120,180 and 240 m چکیده کاملChromium oxide (α-Cr2O3) thin films were prepared using thermal annealing of chromium (Cr)films deposited on quartz substrates by direct current (DC) magnetron sputtering. The annealingprocess of the films was performed for different times of 60, 120,180 and 240 min. The influenceof annealing time on structural, morphological and optical properties of the prepared films wasinvestigated by different analysis including X-ray diffraction (XRD), atomic force microscopy(AFM) and spectrophotometry. The XRD patterns showed that upon thermal annealing the Crfilms transformed to (α-Cr2O3) and the annealing time has a profound effect on crystallinestructure of chromium oxide films. According to AFM results, the films surface morphologieswere strongly dependent on annealing time and an increase in annealing time led to an increasein the grain size as well as in the surface roughness. The transmittance of the as deposited filmwas found very low and it improved after annealing. پرونده مقاله -
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24 - Formation of Cupric Oxide Films on Quartz Substrates by Annealing the Copper Films
Alireza Hojabri Fatemeh Hajakbari Masoumeh NajarsadeghiIn the present work, cupric oxide (CuO) films were obtained through thermal annealing of the copper (Cu) films deposited on quartz substrates by DC magnetron sputtering method. The annealing was performed in air atmosphere for different times ranging from 60-240 min چکیده کاملIn the present work, cupric oxide (CuO) films were obtained through thermal annealing of the copper (Cu) films deposited on quartz substrates by DC magnetron sputtering method. The annealing was performed in air atmosphere for different times ranging from 60-240 min at temperature of 400 ºC. The influence of annealing times on structural and morphological properties of the films was investigated by different analyses. The XRD results showed that the as-deposited film was Cu, while those annealed at different times were composed of CuO. By increasing annealing times up to 180 min, the intensity of CuO diffraction peaks increased and further enhancement of annealing times led to decrease of the crystallinity. Also, the AFM images of the films conformed the dependence of surface morphology to annealing times. پرونده مقاله -
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25 - Effect of Annealing Temperatures on Structural and Morphological Properties of Copper doped Nickel Oxide Thin Films Prepared by RF Magnetron Sputtering
E Feyzi F Hajakbari A HojabriNickel oxide (NiO) thin film is metal oxide that has attracted much attention in recent years due to its environment friendliness. In addition, by doping impurities such as copper (Cu) in NiO films the properties of prepared films can be changed. In this study, Cu:NiO t چکیده کاملNickel oxide (NiO) thin film is metal oxide that has attracted much attention in recent years due to its environment friendliness. In addition, by doping impurities such as copper (Cu) in NiO films the properties of prepared films can be changed. In this study, Cu:NiO thin films were deposited on silicon substrates by RF reactive magnetron sputtering. Then the deposited films were annealed at different temperatures of 200-600 °C. X-ray diffraction (XRD) results showed that all the prepared films were amorphous and the structural properties of films didn’t vary by annealing temperature. Also, atomic force microscopy (AFM) images demonstrated that the surface morphology of the films was affected by annealing temperature. The root mean square (Rms) roughness and average roughness (Ra) values were obtained from AFM observations. FTIR analysis shows the peaks in the wavenumber of 528 cm-1 and 742 cm-1 which are related to Ni-O stretching mode and Cu-O bond bending vibrations. پرونده مقاله -
دسترسی آزاد مقاله
26 - Preparation and Characterization of Molybdenum Trioxide Thin Films Grown by Two-Step Method: DC Sputtering and Plasma Oxidation
Nouri Z Hojabri A Hajakbari FNanostructured molybdenum trioxide (MoO3) films as environmental friendly materials can be used in various filed such as electrochemical energy storage devices, rechargeable batteries and gas sensors. In this work, nanostructured MoO3 thin films were successfully grown چکیده کاملNanostructured molybdenum trioxide (MoO3) films as environmental friendly materials can be used in various filed such as electrochemical energy storage devices, rechargeable batteries and gas sensors. In this work, nanostructured MoO3 thin films were successfully grown on quartz substrates by two-step method. In the first step, molybdenum films were deposited on quartz substrates by DC magnetron sputtering technique. Then the plasma oxidation of molybdenum films was used to prepare molybdenum oxide. The effect of plasma oxidation power and thermal annealing on the structural, morphological and optical properties of the MoO3 films were investigated by different analysis including XRD, AFM, RBS and spectrophotometry. XRD results indicated that the plasma powers effectively influenced the structure of films. The RBS analysis confirmed the presence of Mo and O elements. The AFM images showed that an increment of plasma power leads to decrease the roughness of films and annealing effectively changed the morphology of films. Furthermore, the optical transmittance decreases by increment of the plasma oxidation powers. پرونده مقاله -
دسترسی آزاد مقاله
27 - بررسی خواص مغناطیسی و میکروساختاری نانوکامپوزیتهای Al2O3/CoCrPt جهت ذخیرهسازی دادهها
رضا پولادی محمد الماسی محمد علی بهره وردر عصر حاضر، مغناطیس و بویژه لایه های نازک مغناطیسی در ساخت حافظه ها نقش اساسی دارند. امروزه راهکارهای زیادی برای افزایش حافظه کامپیوترها بررسی می شود. یکی از راههای رسیدن به چنین نتایجی در کاهش اندازه دانه های مغناطیسی با مجزا کردن این دانه ها می باشد، که با افزایش واد چکیده کاملدر عصر حاضر، مغناطیس و بویژه لایه های نازک مغناطیسی در ساخت حافظه ها نقش اساسی دارند. امروزه راهکارهای زیادی برای افزایش حافظه کامپیوترها بررسی می شود. یکی از راههای رسیدن به چنین نتایجی در کاهش اندازه دانه های مغناطیسی با مجزا کردن این دانه ها می باشد، که با افزایش وادارندگی مغناطیسی همراه است. در کار حاضر با استفاده از روش مگنوترون، نانوکامپوزیت های زمینه فلزی CoCrPt با درصد های مختلف Al2O3 ساخته می شوند. در این حالت، لایه تقریباً آمورف تشکیل می شود که دانه های بسیار ریز دارند. با آنیل کردن آنها در دماهای مختلف و تحت زمانهای متفاوت، دما و زمان بهینه، برای رسیدن به حالت کریستالی فیلم مورد بررسی قرار گرفته است. با مطالعه و اندازه گیری میزان نیروی کوئرسیویته به کمک VSM، میزان افزایش آن در شرایط مختلف برای رسیدن به حالت مطلوب محقق گردیده است. با عملیات حرارتی، لایه های CoCrPt/Al2O3، نیروی وادارندگی به نحو چشمگیری افزایش یافته است، که مقدار این افزایش2500 اورستد است. این افزایش نیروی وادارندگی می تواند افق جدیدی را بر روی دنیای الکترونیک باز کند. پرونده مقاله -
دسترسی آزاد مقاله
28 - Thermal Stability and Dynamic Magnetic Properties of NiO/Fe Multilayered Thin Films Prepared by Oblique-Angle Sputtering Technique
khalil gheisari C.K. OngIn this work, the bilayer NiO/Fe thin films compared with single-layer Fe film were deposited on Si (100) substrate using the sputtering technique at deposition angles of 0° and 31.5°. Structure, the static magnetic properties, and the temperature dependence of چکیده کاملIn this work, the bilayer NiO/Fe thin films compared with single-layer Fe film were deposited on Si (100) substrate using the sputtering technique at deposition angles of 0° and 31.5°. Structure, the static magnetic properties, and the temperature dependence of the dynamic magnetic properties in the range from 300 K to 420 K have been investigated. The results show that the nanocrystalline BCC phase of Fe with the average crystallite size of 11-12 nm and (110) preferred orientation is formed during the deposition process. The resonance frequency is found to rise from 1.03 GHz to 1.13 GHz by employing the NiO sublayer for the typically deposited Fe film. Moreover, the resonance frequency increases for the NiO/Fe films from 1.13 GHz to 1.67 GHz as the deposition angle increases from 0° and 31.5° as a result of the increase in the magnetic anisotropy from 16 Oe to 45 Oe. The permeability values decrease for both as-deposited films with increasing temperature; however, the higher values of the permeability are observed for the film obtained at a deposition angle of 31.5°. پرونده مقاله -
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29 - The tribological properties of Cu-Ni3Al-MoS2 composite coating deposited by magnetron sputtering
Mahdi Mirzaaghaei Mohammad Hossein Enayati Mahdi AhmadiIn industrial applications, most materials are exposed to wear and friction because multiple conditions are used. However, the tribological properties of these materials can be improved with different techniques. One such technique that improves the frictional property چکیده کاملIn industrial applications, most materials are exposed to wear and friction because multiple conditions are used. However, the tribological properties of these materials can be improved with different techniques. One such technique that improves the frictional property of a surface is the use of self-lubricating coatings. In this study, multicomponent coatings of nominal composition Cu-Ni3Al-MoS2 have been sputter from the target using the best sputtering condition to get a good morphology and microstructure of the coating. The morphology and micro structure of the coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy depressive spectroscopy (EDS). The measured microhardness of this coating was 380 HV over 25 g load. Tribological properties of Cu-Ni3Al-MoS2 coatings were investigated using ball-on-disk (BOD) tribometer at atmospheric condition of room temperature. These composite coatings showed a good morphology and adhesion of the coating to the substrate, also it had acceptable friction coefficient and higher wear resistance, because it has hard matrix containing Cu-Ni3Al and MoS2 Nano particles. پرونده مقاله -
دسترسی آزاد مقاله
30 - Fabricating the Tribological Properties and Investigating of Ni3Al-MoS2 Composite Coating
Mahdi Mirzaaghaei Mohammad-Hossein Enayati Mahdi AhmadiSelf-lubricant coatings are among the newly improved type of coatings to reduce the coefficient of friction and protect the substrate in various conditions. Magnetron sputtering is the best technology to fabricate coatings with good morphology. In this paper, the tribol چکیده کاملSelf-lubricant coatings are among the newly improved type of coatings to reduce the coefficient of friction and protect the substrate in various conditions. Magnetron sputtering is the best technology to fabricate coatings with good morphology. In this paper, the tribological properties of magnetron sputtered Ni3Al-MoS2 coating on 4340 steel are reported. For this purpose, five tablets of Ni3Al-30 wt.% MoS2 were prepared as the target material and were placed in a copper holder. At last, we have sputtered from the target using the best sputtering condition to get a good morphology and microstructure of the coating. The morphology and microstructure of the coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The tribological properties of Ni3Al-MoS2 coating were investigated using a ball-on-disc tribometer at atmospheric conditions at room temperature. SEM was used to examine the morphology of the wear track after the ball-on-disc test. The Ni3Al-MoS2 composite coating showed lower frictions coefficient and higher wear resistance because of the hard Ni3Al matrix and soft MoS2 particles. پرونده مقاله -
دسترسی آزاد مقاله
31 - Electrochemical Evaluation of Hydroxyapatite/ZrN Coated Magnesium Biodegradable Alloy in Ringer Solution as a Simulated Body Fluid
Seyed Rahim Kiahosseini Abdollah Afshar Majid Mojtahedzadeh Larijani Mardali YousefpourMagnesium alloys as biodegradable materials can be used in body as an implant materials but since they have poor corrosion resistance, it is required to decrease their corrosion rate by biocompatible coatings. In this study, hydroxyapatite (HA) coatings in the presence چکیده کاملMagnesium alloys as biodegradable materials can be used in body as an implant materials but since they have poor corrosion resistance, it is required to decrease their corrosion rate by biocompatible coatings. In this study, hydroxyapatite (HA) coatings in the presence of an intermediate layer of ZrN as a biocompatible material, deposited on AZ91 magnesium alloy by ion beam sputtering method at 300 °C temperature and at different times 180, 240, 300, 360 and 420 min. Then changes in corrosion resistance of samples in Ringer's solution as a solution similar to the human body was evaluated in two ways, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). To investigate the causes of the destruction of the samples, the surface of samples was studied by scanning electron microscopy (SEM). The results showed that because of porous coatings created, the corrosion potential of the samples was about +55mV higher than the uncoated substrate that by changing the deposition time, was not observed the significant change But with increasing deposition time to 360 min, corrosion current decreased which represents an increase of corrosion resistance of magnesium alloy in body solution. However, a further increase in deposition time to 420 min, due to increase thickness and stress in the layer, the corrosion resistance of the samples was reduced. The results of the EIS confirm the corrosion behavior of the polarization method, too.   پرونده مقاله -
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32 - اثر افزودن سیلیسیم بر رفتار مکانیکی و خوردگی پوشش کاربید تانتالم تولید شده به روش کندوپاش مگنترونی
علیرضا حسینی میناسادات امامیان مصطفی علیشاهیدر این پژوهش پوششهای Ta، TaC و TaSiC به روش کندوپاش مگنترونی غیرواکنشی لایهنشانی شده و خواص ساختاری، ریزساختاری، مکانیکی و خوردگی بررسی شده است. نتایج XRD نشان دادند که پوشش Ta ساختار کریستالی تانتالم α، پوشش TaC ساختار کریستالی TaC0.6 و پوشش TaSiC ماهیت شبهآمو چکیده کاملدر این پژوهش پوششهای Ta، TaC و TaSiC به روش کندوپاش مگنترونی غیرواکنشی لایهنشانی شده و خواص ساختاری، ریزساختاری، مکانیکی و خوردگی بررسی شده است. نتایج XRD نشان دادند که پوشش Ta ساختار کریستالی تانتالم α، پوشش TaC ساختار کریستالی TaC0.6 و پوشش TaSiC ماهیت شبهآمورف از خود نشان دادند. در این ارتباط، پوشش Ta ریزساختاری ستونی با زبری بالا و تنش پسماند کششی از خود نشان داد، در حالیکه افزودن کربن و سیلیسیم به پوشش سبب فشردهشدن ریزساختار، کاهش زبری سطح و تغییر ماهیت تنش پسماند از کششی به فشاری شد. همچنین نتایج آزمون نانوفرورونده نشان داد که افزودن کربن به پوشش تانتالم باعث افزایش حدود چهار برابری سختی پوشش میشود، ولی افزودن سیلیسیم به پوشش TaC سختی پوشش را اندکی کاهش میدهد. مطالعات خوردگی نشان داد همه پوششها نسبت به زیرلایه ST37 ماهیتی کاتدی از خود نشان دادند که میتواند منجر به خوردگی گالوانیک شود. علاوه بر این نتایج خوردگی نشان داد که پوشش Ta بازده حفاظتی به میزان ٪9/78 برای فولاد ساده کربنی را به همراه دارد و افزودن کربن و سیلیسیم به پوشش سبب افزایش بازده حفاظتی به مقادیر ٪1/90 و ٪5/95 به ترتیب برای پوششهای TaC و TaSiC میشود .در این ارتباط نقش این عناصر در فشردگی پوشش و کاهش مسیرهایی که محلول خورنده میتواند به زیرلایه برسد، کلیدی تشخیص داده شد. پرونده مقاله -
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33 - بررسی اثر دمای زیرلایه بر خواص ساختاری و فیزیکی لایه نازک کربن انباشت شده به روش کندوپاش پرتو یونی
الهام محقق پور مرجان رجبی رضا غلامی پور مجید مجتهدزاده لاریجانی شهاب شیبانیدر تحقیق حاضر اثر دمای زیرلایه در محدوده ºC 400-36 بر خواص ساختاری و فیزیکی لایه نازک کربن ایجاد شده بر سطح شیشه به روش کندوپاش پرتو یونی بررسی شده است. خواص نوری و ساختاری لایه به ترتیب به وسیله طیف سنجی UV-visible، طیف سنجی رامان و میکروسکوپ نیروی اتمی مورد مطالع چکیده کاملدر تحقیق حاضر اثر دمای زیرلایه در محدوده ºC 400-36 بر خواص ساختاری و فیزیکی لایه نازک کربن ایجاد شده بر سطح شیشه به روش کندوپاش پرتو یونی بررسی شده است. خواص نوری و ساختاری لایه به ترتیب به وسیله طیف سنجی UV-visible، طیف سنجی رامان و میکروسکوپ نیروی اتمی مورد مطالعه قرار گرفته است. اندازه گیری طیف عبور نمونه ها کاهش میزان عبور نور در محدوده مرئی با افزایش دمای انباشت را نشان می دهد. طیف رامان لایه ها نشان می دهد که ساختار لایه نازک کربن آمورف با افزایش دمای انباشت به سمت کربن آمورف گرافیتی تغییر می کند. بررسی لایه های انباشت شده در دمای بالاتر از ºC100 نشاندهنده روند کاهشی مقاومت الکتریکی اندازه گیری شده توسط روش چهار کاوه و انرژی نوار ممنوعه با افزایش دمای انباشت می باشد. در حالی که نتایج بررسی مورفولوژی سطح افزایش زبری سطح در اثر افزایش دمای زیرلایه را نشان می دهد. در نمونه های انباشت شده در دمای ºC100، حداقل اندازه خوشه های کریستالی گرافیتی با پیوندهایsp2 برابر با nm 36/0 و حداکثر انرژی نوار ممنوعه برابر با eV‎ 3 می باشد. پرونده مقاله -
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34 - بررسی رفتار خوردگی پوشش تانتالم لایهنشانی شده به روش کندوپاش مگنترونی
مصطفی علیشاهی فرزاد محبوبی سیدمحمد موسوی خوئیدر این پژوهش پوشش تانتالم به روش کندوپاش مگنترونی جریان مستقیم روی سیلیکون (۱۰۰) و فولاد زنگنزن L۳۱۶ لایهنشانی شد. خواص ساختاری پوشش تانتالم به کمک آزمون پراش پرتو ایکس ارزیابی شده و از میکروسکوپهای الکترونی عبوری و روبشی و همچنین میکروسکوپ نیروی اتمی جهت بررسی سطح م چکیده کاملدر این پژوهش پوشش تانتالم به روش کندوپاش مگنترونی جریان مستقیم روی سیلیکون (۱۰۰) و فولاد زنگنزن L۳۱۶ لایهنشانی شد. خواص ساختاری پوشش تانتالم به کمک آزمون پراش پرتو ایکس ارزیابی شده و از میکروسکوپهای الکترونی عبوری و روبشی و همچنین میکروسکوپ نیروی اتمی جهت بررسی سطح مقطع و مورفولوژی سطح پوشش استفاده شد. افزون بر این، رفتار خوردگی پوشش تانتالم در مقایسه با فولاد زنگنزن L۳۱۶ به کمک آزمون پلاریزاسیون پتانسیودینامیک بررسی شده و از آزمون طیفسنجی امپدانس الکتروشیمیایی جهت تعیین مکانیزمهای خوردگی استفاده شد. نتایج نشان دادند که استفاده از لایه آستری نیترید تانتالم، میتواند سبب تغییر ساختار کریستالی پوشش تانتالم از مخلوط فازی α و β به ساختار تک فاز α، و کاهش مقاومت الکتریکی پوشش از حدود ۹۰ به ۱۵ میکرواهم در سانتیمتر شود. همچنین مطالعات میکروسکوپی نشان دادند که پوشش تانتالم ساختاری ستونی و بسیار فشرده با سطحی یکنواخت و بدون عیب از خود نشان داده و زبری میانگین آن کمتر از ۶ نانومتر اندازهگیری شد. نتایج آزمونهای خوردگی نشان داد که پوشش تانتالم مانند یک سد فیزیکی از تماس محلول خورنده با زیرلایه جلوگیری کرده و بازده حفاظت بیشتر از ۷۰ درصد از سبب میشود. در این ارتباط، نفوذ محلول خورنده به زیرلایه از طریق حفرات راهباز موجود در پوشش به عنوان مکانیزم خوردگی پوشش تانتالم شناخته شد و شاخص تخلخل پوشش حدود ۶ درصد تعیین شد. پرونده مقاله -
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35 - بررسی چقرمگی شکست و حساسیت به نرخ کرنش لایه نازک نیترید تانتالوم تولید شده به روش کندوپاش مغناطیسی واکنشی
Siavash فیروزآبادی کامران دهقانی مالک نادری فرزاد محبوبینیترید تانتالوم به دلیل سختی بالا و مقاومت به خوردگی خوب توانسته است توجهات زیادی را به عنوان پوششی مناسب جلب نماید. اما چقرمگی شکست لایههای نازک نیترید تانتالوم که یکی از عوامل تاثیرگذار بر طول عمر پوشش است، هنوز به خوبی بررسی نشده است. در این پژوهش، برای نخستین بار، چکیده کاملنیترید تانتالوم به دلیل سختی بالا و مقاومت به خوردگی خوب توانسته است توجهات زیادی را به عنوان پوششی مناسب جلب نماید. اما چقرمگی شکست لایههای نازک نیترید تانتالوم که یکی از عوامل تاثیرگذار بر طول عمر پوشش است، هنوز به خوبی بررسی نشده است. در این پژوهش، برای نخستین بار، چقرمگی شکست، پلاستیسیته و حساسیت به نرخ کرنش لایه های نازک نیترید تانتالوم به کمک روش نانو فرورونده بررسی و ارزیابی شد. در این بررسی نشان داده شده که تغییرات چقرمگی شکست فازهای مختلف نیترید تانتالوم از MPa√m 6/0 تا MPa√m 7/8 بسته به میزان نیتروزن موجود در سیستم لایه نشانی و به تبع آن نیتروژن موجود در شبکه نیترید تانتالوم افزایش مییابد. همچنین دو فاز مهم نیترید تانتالوم یعنی γ-Ta2N و δ-TaN دارای حساسیت به نرخ کرنش منفی و مثبت هستند که میتوان این رفتار را به تغییرات ساختار فازی حین انجام آزمون نسبت داد. پرونده مقاله
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