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A PASSIVATION STUDY OF Ti-MODIFIED Fe-BASE ALLOY SYNTHESIZED BY MAGNETRON SPUTTERING TECHNIQUE
A PASSIVATION STUDY OF Ti-MODIFIED Fe—BASE ALLOY SYNTHESIZED BY MAGNETRON SPUTTERING TECHNIQUE

LI Huiqin,ZHOU Honghui,YANG Dejun,SUN DongbaiUniversity of Science,Technology Beijing,China,
LI Huiqin
,ZHOU Honghui,YANG Dejun,SUN DongbaiUniversity of Science and Technology Beijing,China

金属学报(英文版) , 1994,
Abstract: A set of fracture device was designed on the basis of traditional scratching-electrode technology and used to study the passivation process of two magnetron-sputtered stainless sleel coatings (amorphous and crystalline struture). The results of fracture tests in 3.5 % NaCl aqueous solution show that the amorphous alloy has a high bare surface reactivity and a high passive rate in comparison with the crystalline alloy. The effect of structure on corrosion resistance is also discussed. The excellent corrosion resistance of amorphous alloy is considered to be partly attributed to its great passivation ability.
Nanocrystalline GaN and GaN: H films grown by RF-magnetron sputtering
Leite, D. M. G.;Pereira, A. L. J.;Silva, L. F. da;Silva, J. H. Dias da;
Brazilian Journal of Physics , 2006, DOI: 10.1590/S0103-97332006000600048
Abstract: the structural and optical properties of nanocrystalline gan and gan:h films grown by rf-magnetron sputtering are focused here. the films were grown using a ga target and a variety of deposition parameters (n2/h2/ar flow rates, rf power, and substrate temperatures). si (100) and fused silica substrates were used at relatively low temperatures (ts < 420k). the main effects resulting from the deposition parameters variations on the films properties were related to the presence of hydrogen in the plasma. the x-ray diffraction analysis indicates that the grain sizes ( ~ 15nm) and the crystallized volume fraction significantly decrease when hydrogen is present in the plasma. the optical absorption experiments indicate that the hydrogenated films have absorption edges very similar to that of gan single crystal films reported in the literature, while the non-hydrogenated samples present larger absorption tails encroaching into the gap energies.
Structural and Optical Properties of HfLaO Films Prepared by RF Magnetron Sputtering
LI Zhi, MIAO Chun-Yu, MA Chun-Yu, ZHANG Qing-Yu
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.01281
Abstract: HfLaO films doped with different La contents, varying from 17% to 37%, were deposited using RF magnetron sputtering. The structure, thermal stability, surface morphology, and optical properties of HfLaO films were investigated by X―ray diffraction (XRD), atomic force microscope (AFM) and spectrophotometry. The results indicate that as―deposited HfLaO with 25%―37% La films are amorphous. With the increase of La contents, the crystallization temperature for HfLaO films is increased. The HfLaO film with 37% La remains amorphous even after annealed at 900 . The AFM images show amorphous HfLaO films, which imply a good thermal stability have a relatively smooth surface. The average transmittance in the visible range is above 82% for all the films. The amorphous structure yields films of significantly higher transparency than the polycrystalline structure does. The refractive indices of the films are determined to be in the range 1.77―1.87. As the La concent increases the refractive indices of the films are initially increased and then decreased. The optical band gap of the HfLaO films decreases to 5.9eV (La 17%), 5.87eV(La 25%), 5.8eV(La 33%), 5.77eV(La 37%), respectively.
Growth of Films by RF Magnetron Sputtering: Studies on the Structural, Optical, and Electrochromic Properties  [PDF]
S. Subbarayudu,V. Madhavi,S. Uthanna
ISRN Condensed Matter Physics , 2013, DOI: 10.1155/2013/806374
Abstract: Molybdenum oxide (MoO3) films were deposited on glass and silicon substrates held at temperature 473?K by RF magnetron sputtering of molybdenum target at various oxygen partial pressures in the range mbar. The deposited MoO3 films were characterized for their chemical composition, crystallographic structure, surface morphology, chemical binding configuration, and optical properties. The films formed at oxygen partial pressure of mbar were nearly stoichiometric and nanocrystalline MoO3 with crystallite size of 27?nm. The Fourier transform infrared spectrum of the films formed at mbar exhibited the characteristics vibrational bands of MoO3. The optical band gap of the films increased from 3.11 to 3.28?eV, and the refractive index increased from 2.04 to 2.16 with the increase of oxygen partial pressure from to mbar, respectively. The electrochromic performance of MoO3 films formed on ITO coated glass substrates was studied and achieved the optical modulation of about 13% with color efficiency of about 20 cm2/C. 1. Introduction Transition metal oxides constitute an interesting group of semiconducting materials because of their technological applications in various fields such as display devices, optical smart windows, electrochromic devices, and gas sensors [1, 2]. Among the transition metal oxides, molybdenum oxide (MoO3) exhibits interesting structural, chemical, and optical properties. MoO3 finds application as a cathode material in the development of high energy density solid state microbatteries [3, 4]. It is considered as a chromogenic material since it exhibits electro-, photo-, and gaso chromic (coloration) effects by virtue of which material is of potential for the development of electronic display devices [5]. MoO3 films in nanocrystalline form also find applications in sensors and lubricants [6]. It is also a promising candidate as a back contact layer for cadmium telluride solar cells in superstrate configuration because of its high work function, which possibly reduces the back contact barrier [7]. Various physical thin film deposition techniques such as thermal evaporation [8, 9], electron beam evaporation [10, 11], pulsed laser deposition [12, 13], and sputtering [14–18] and chemical methods such as electrodeposition [19], chemical vapour deposition [20], spray pyrolysis [21, 22], and sol-gel process [23–25] were employed for the growth of MoO3 films. Among these films deposition techniques, magnetron sputter deposition is an industrially practiced technique for the growth of oxide films. The physical properties of the sputter deposited MoO3
Al-Doping Effect on the Surface Morphology of ZnO Films Grown by Reactive RF Magnetron Sputtering  [PDF]
Erica Pereira da Silva, Michel Chaves, Gilvan Junior da Silva, Larissa Baldo de Arruda, Paulo Noronha Lisboa-Filho, Steven Frederick Durrant, José Roberto Ribeiro Bortoleto
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.412096
Abstract:

Zinc oxide (ZnO) and aluminum-doped zinc oxide (ZnO:Al) thin films were deposited onto glass and silicon substrates by RF magnetron sputtering using a zinc-aluminum target. Both films were deposited at a growth rate of 12.5 nm/min to a thickness of around 750 nm. In the visible region, the films exhibit optical transmittances which are greater than 80%. The optical energy gap of ZnO films increased from 3.28 eV to 3.36 eV upon doping with Al. This increase is related to the increase in carrier density from 5.9 × 1018 cm-3 to 2.6 × 1019 cm-3. The RMS surface roughness of ZnO films grown on glass increased from 14 to 28 nm even with only 0.9% at Al content. XRD analysis revealed that the ZnO films are polycrystalline with preferential growth parallel to the (002) plane, which corresponds to the wurtzite structure of ZnO.

Effect of RF power on the properties of transparent conducting zirconium-doped zinc oxide films prepared by RF magnetron sputtering
Lii Mao-Shui,Pang Zhi-Yong,Xiu Xian-Wu,Dai Ying,Hart Sheng-Hao,
吕茂水
,庞智勇,修显武,戴 瑛,韩圣浩

中国物理 B , 2007,
Abstract: Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency (RF) magnetron sputtering at room temperature. The RF power is varied from 75 to 150W. At first the crystallinity and conductivity of the film are improved and then both of them show deterioration with the increase of the RF power. The lowest resistivity achieved is 2.07×10-3\Omegacm at an RF power of 100W with a Hall mobility of 16cm2V-1s-1 and a carrier concentration of 1.95×1020cm-3. The films obtained are polycrystalline with a hexagonal structure and a preferred orientation along the c-axis. All the films have a high transmittance of approximately 92% in the visible range. The optical band gap is about 3.33eV for the films deposited at different RF powers.
Design and preparation of stress-free epitaxial BaTiO3 polydomain films by RF magnetron sputtering  [cached]
Wei Zhang, Meiling Yuan, Xianyang Wang, Wei Pan, Chun-Ming Wang and Jun Ouyang
Science and Technology of Advanced Materials , 2012,
Abstract: Domain structures of BaTiO3 thick films grown on (100) SrTiO3 single-crystal substrates were engineered using an RF magnetron sputtering deposition process. By tuning the sputtering power and cooling rate and using an off-axis sputtering technique to prepare conducting perovskite oxide bottom electrode with heteroepitaxial quality, we have deposited epitaxial tetragonal single-domain and polydomain BaTiO3 films with a self-assembled three-domain architecture. The electrical properties and microstructure of the BaTiO3 films were characterized, and a c/a1/a2 cellular polydomain structure was clearly observed in as-grown films by optical microscopy. Such a polydomain structure was a consequence of a complete relaxation of misfit stresses of the film. Engineering of this self-assembled microstructure has great potential in providing large, field-tunable pyroelectric and electromechanical responses in next-generation microelectronic devices and micro-electro-mechanical systems (MEMS).
Ar Pressure Dependence of the Properties of Molybdenum-doped ZnO Films Grown by RF Magnetron Sputtering
Xianwu XIU,Zhiyong PANG,Maoshui LV,Ying DAI,Li''''na YE,Shenghao HAN,
Xianwu XIU
,Zhiyong PANG,Maoshui LV,Ying DAI,Li′na YE,Shenghao HAN

材料科学技术学报 , 2007,
Abstract: Transparent conducting oxide film of molybdenum-doped zinc oxide (MZO) with high transparency and relatively low resistivity was prepared by RF (radio frequency) magnetron sputtering at room temperature. The structural, electrical, and optical properties of the films deposited under different Ar pressure were investigated.XRD (X-ray diffraction) patterns show that the nature of the films is polycrystalline with a hexagonal structure and a preferred orientation along the c-axis. The resistivity increases as Ar pressure increases. The lowest range exceeds 88% for all the samples. The optical band gap decreases from 3.27 to 3.15 eV with increasing Ar pressure from 0.6 to 3.0 Pa.
RF Power and Thermal Annealing Effect on the Properties of Zinc Oxide Films Prepared by Radio Frequency Magnetron Sputtering  [PDF]
Chaoyang Li,Mamoru Furuta,Tokiyoshi Matsuda,Takahiro Hiramatsu,Hiroshi Furuta,Takashi Hirao
Advances in Materials Science and Engineering , 2007, DOI: 10.1155/2007/26459
Abstract: Polycrystalline zinc oxide (ZnO) films were prepared by radio frequency (RF) magnetron sputtering under different powers. The XRD results showed that ZnO crystallite size along c-axis decreased by 43% with deposition power increased from 60 W to 300 W, increased 36% with annealing temperature rising to 400∘C. TDS measurement revealed that the desorption peaks of both atomic Zn (60 W-deposited) and oxygen molecule (180 W and 300 W-deposited) obtained from ZnO films were originated from 300∘C. When annealing temperature was higher than 300∘C, the sheet resistance dramatically decreased, and compressive stress in the (002) plane changed to tensile stress as well. The comparison measurements of ZnO films crystallinity strongly suggested that both lower deposition power and certain thermal annealing temperature over 300∘C would contribute to the formation of high quality ZnO films.
Structural, Optical, and Electrochromic Properties of Pure and Mo-Doped WO3 Films by RF Magnetron Sputtering  [PDF]
Vempuluri Madhavi,Paruchuri Kondaiah,Obili Mahammad Hussain,Suda Uthanna
Conference Papers in Science , 2013, DOI: 10.1155/2013/104047
Abstract: Pure and Mo-doped WO3 films were formed on ITO-coated glass substrate held at 473?K by RF magnetron sputtering technique. The structural, morphological, and optical properties of pure and Mo-doped WO3 thin films have been systematically studied. The structural properties revealed that the pure WO3 films exhibited a (020) reflection related to the orthorhombic phase of WO3, whereas Mo-doped films showed (200) reflection. The surface morphology revealed that pure WO3 films showed the dense surface and Mo-doped films contained agglomerated grains which were uniformly distributed on the surface of the substrate. The optical transmittance decreased from 85% to 75% for pure and Mo-doped WO3 films, respectively. The electrochromic properties of the films were measured by cyclic voltametry in 1?M Li2SO4 electrolyte solution. The optical modulation of pure WO3 films at near IR was 50%, and the calculated color efficiency was 33.8?cm2/C, while in Mo-doped WO3 the efficiency improved to 42.5?cm2/C. 1. Introduction Tungsten oxide (WO3) is the most widely used electrochromic material because of easiness in synthesis and favorable electrical and optical properties. The application of electrochromic materials for smart windows, displays, and antiglare mirrors and several applications have been developed such as control of incoming daylight into buildings, smart windows, rearview mirrors, and aphotochromic and electrochromic devices [1–3]. Tungsten oxide is the extensively studied electrochromic material [4, 5]. Doping of vanadium, niobium, nitrogen, titanium, or nickel to WO3 enhances in the electrochromic properties. Muthu Karuppasamy and Subramanyam [6] reported that the color efficiency decreased from 121 to 13?cm2/C with increase of vanadium doping of 9 at. % in tungsten oxide films deposited by DC magnetron sputtering. Bathe and Patil [7] studied the electrochromic properties of niobium-doped WO3 films, and the coloration efficiency decreased with the increase of niobium doping. Sun et al. [8] studied the nitrogen-doped WO3 films formed by reactive DC pulsed sputtering and the color efficiency achieved to 45?cm2/C at 5 at. % nitrogen doped films. Karuppasamy and Subrahmanyam [9] studied the electrochromic properties of titanium doped tungsten oxide films and realized the improvement in the electrochromic properties with the increase of titanium doping. Gesheva et al. [10] studied MoO3-WO3 films formed by chemical vapour deposition method and showed the color efficiency of 141?cm2/C when compared to 84?cm2/C for WO3 and 39?cm2/C for MoO3 films. Valyukh et al. [11]
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