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1.
The effect of substrate roughness on growth of ultra thin diamond-like carbon (DLC) films has been studied. The ultra thin DLC films have been deposited on silicon substrates with initial surface roughness of 0.15, 0.46 and 1.08 nm using a filted cathodic vacuum arc (FCVA) system. The films were characterized by Raman spectroscope, transmission electron microscope (TEM) and atomic force microscopy (AFM) to investigate the evolution of the surface roughness as a function of the film thickness. The experimental results show that the evolution of the surface morphology in an atomic scale depends on the initial surface morphology of the silicon substrate. For smooth silicon substrate (initial surface roughness of 0.15 nm), the surface roughness decreased with DLC thickness. However, for silicon substrate with initial surface roughness of 0.46 and 1.08 nm, the film surface roughness decreased first and then increased to a maximum and subsequently decreased again. The preferred growth of the valley and the island growth of DLC were employed to interpret the influence of substrate morphology on the evolution of DLC film roughness. 相似文献
2.
S. Knebel A. Kyriakidou H. Bracht H. Rösner G. Wilde 《Applied Physics A: Materials Science & Processing》2011,103(1):149-158
Stoichiometric mixed germanate–silicate glass films were fabricated on boron-doped silicon substrates by means of a sol–gel
based synthesis procedure. In order to initiate the growth of elemental germanium (Ge) nanocrystals, the glass films were
annealed in forming gas at temperatures between 600 and 1000°C. High-resolution and conventional transmission electron microscopy
show that the shape and size of Ge nanocrystals embedded in the glass film are strongly influenced by the annealing conditions.
Energy-dispersive X-ray analysis reveals that Ge segregates at the interface to the silicon substrate and evaporates from
the free surface. This leads to a denuded zone of Ge nanoparticles close to the Si substrate and the SiO2 surface. Capacitance–voltage measurements of a metal–oxide–semiconductor structure with and without Ge particles demonstrate
the charge-storage characteristic of the thin-layer structure. We identify clear trends in the electrical properties of the
nanoparticles as a function of the annealing conditions and observe correlations between trapped charge and particle density. 相似文献
3.
The initial stages of Heusler alloy (Co2FeSi) thin film growth by reactive epitaxy on the Si(100)2 × 1 surface are studied, and formation conditions for this alloy
are found. At a substrate temperature of lower than, or equal to, 180°C, an island film of ternary Co-Fe-Si film grows on
the surface. The silicon content in this film is lower than in the compound to be synthesized. The film becomes continuous
when its thickness exceeds 1.2 nm. It is shown that post-growth annealing at 240°C can raise the silicon content in the film
and be conducive to obtaining Heusler alloy of a desired composition. In situ measurements of the films show that ferromagnetic
ordering in them has a threshold and shows up at the coalescence growth stage of the Co-Fe-Si island alloy. 相似文献
4.
V. K. Turkov V. S. Vlasov L. N. Kotov V. A. Ustyugov M. P. Lasek Yu. E. Kalinin A. V. Sitnikov 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(10):1223-1227
The effect of annealing on the structure and microwave magnetic properties of composite single-layer and multilayer films is investigated. It is found that as the threshold annealing temperature is attained, the width of the FMR line increases abruptly, depending on the concentration ratio of metallic alloy and dielectric. It is shown that the FMR line broadening is also associated with the occurrence of and increase in high-frequency modes of absorption. The surfaces of annealed and unannealed films are investigated at various concentrations of metallic alloys and dielectrics using an atomic force microscope. The strong change in the magnetic characteristics after film annealing is associated with a change in surface roughness and inhomogeneity, and in the size distribution of nano- and submicron formations and their spacing. 相似文献
5.
K. Siraj M. Khaleeq-ur-RahmanM.S. Rafique M.Z. MunawarS. Naseem S. Riaz 《Applied Surface Science》2011,257(15):6445-6450
Cobalt-DLC multilayer films were deposited with increasing content of cobalt, keeping carbon content constant by pulsed laser deposition technique. A cobalt free carbon film was also deposited for comparison. Excimer laser was employed to ablate the materials onto silicon substrate, kept at 250 °C, while post-deposition annealing at 400 °C was also performed in situ. The formation of cobalt grains within the carbon matrix in Co-DLC films can be seen through scanning electron and atomic force micrographs while no grains on the surface of the cobalt-free DLC film were observed. Raman spectra of all the films show D- and G-bands, which is a confirmation that the films are DLC in nature. According to Vibrating sample magnetometer (VSM) measurements, the DLC films with cobalt revealed ferromagnetic behaviour whereas the cobalt free DLC film exhibited diamagnetic behaviour. The pure DLC film also shows ferromagnetic nature when diamagnetic background is subtracted. Spectroscopic Ellipsometry (SE) analysis showed that the optical band gaps, refractive indices and extinction coefficients of Co-DLC films can be effectively tuned with increasing content of cobalt. 相似文献
6.
采用双极脉冲磁控反应溅射法在不同参数条件下制备了一系列氮化硅薄膜。利用数字式显微镜和紫外-可见光光谱仪研究了沉积薄膜的表面形貌及其光学带隙,利用共焦显微拉曼光谱仪比较了硅衬底、氮化硅薄膜退火前后的拉曼光谱。结果表明,氮气流量对薄膜的光学带隙影响较大,制备的薄膜主要为富硅氮化硅薄膜。原沉积薄膜的拉曼光谱存在明显的非晶硅和单晶硅峰,退火处理后非晶硅峰减弱或消失,表明薄膜出现明显的结晶化;单晶硅峰出现频移现象,表明薄膜中出现硅纳米颗粒,平均尺寸约为6.6 nm。 相似文献
7.
In this paper we investigate the formations and morphological stabilities of Co-silicide films using 1-8-nm thick Co layers sputter-deposited on silicon(100) substrates.These ultrathin Co-silicide films are formed via solid-state reaction of the deposited Co films with Si substrate at annealing temperatures from 450℃ to 850℃.For a Co layer with a thickness no larger than 1 nm,epitaxially aligned CoSi2 films readily grow on silicon(100) substrate and exhibit good morphological stabilities up to 600℃.For a Co layer thicker than 1 nm,polycrystalline CoSi and CoSi2 films are observed.The critical thickness below which epitaxially aligned CoSi2 film prevails is smaller than the reported critical thickness of the Ni layer for epitaxial alignment of NiSi2 on silicon(100) substrate.The larger lattice mismatch between the CoSi2 film and the silicon substrate is the root cause for the smaller critical thickness of the Co layer. 相似文献
8.
Anastasiya Olegovna Puchkova Petr Sokolov Yuri Vladimirovich Petrov Nina Anatolievna Kasyanenko 《Journal of nanoparticle research》2011,13(9):3633-3641
New simple way for silver deoxyribonucleic acid (DNA)-based nanowires preparation on silicon surface was developed. The electrochemical
reduction of silver ions fixed on DNA molecule provides the forming of tightly matched zonate silver clusters. Highly homogeneous
metallic clusters have a size about 30 nm. So the thickness of nanowires does not exceed 30–50 nm. The surface of n-type silicon
monocrystal is the most convenient substrate for this procedure. The comparative analysis of DNA metallization on of n-type
silicon with a similar way for nanowires fabrication on p-type silicon, freshly cleaved mica, and glass surface shows the
advantage of n-type silicon, which is not only the substrate for DNA fixation but also the source of electrons for silver
reduction. Images of bound DNA molecules and fabricated nanowires have been obtained using an atomic force microscope and
a scanning ion helium microscope. DNA interaction with silver ions in a solution was examined by the methods of ultraviolet
spectroscopy and circular dichroism. 相似文献
9.
In this paper we investigate the formations and morphological stabilities of Co-silicide fihns using 1-8-nm thick Co layers sputter-deposited on silicon (100) substrates. These ultrathin Co-silicide films are formed via solid-state reaction of the deposited Co films with Si substrate at annealing temperatures from 450 ℃ to 850 ℃. For a Co layer with a thickness no larger than i nm, epitaxially aligned CoSi2 films readily grow on silicon (100) substrate and exhibit good morphological stabilities up to 600 ℃. For a Co layer thicker than 1 nm, polycrystalline CoSi and CoSi2 films are observed. The critical thickness below which epitaxially aligned CoSi2 film prevails is smaller than the reported critical thickness of the Ni layer for epitaxial alignment of NiSi2 on silicon (100) substrate. The larger lattice mismatch between the CoSi2 film and the silicon substrate is the root cause for the smaller critical thickness of the Co layer. 相似文献
10.
I. S. Grudzinskaya Z. Ya. Kosakovskaya V. N. Reshetov A. A. Chaban 《Acoustical Physics》2001,47(5):548-551
The Young modulus of a thin layer consisting of densely packed carbon nanotubes oriented normally to a substrate is measured using a scanning probe atomic force microscope. It is found that the adhesion of the film and the silicon substrate is not very strong, and, at certain conditions, this may lead to an intense energy dissipation in an oscillatory system loaded by the film. 相似文献
11.
《Superlattices and Microstructures》1988,4(6):709-712
Measurement of gold surface self-diffusion by the method of surface profile decay, using a scanning tunneling microscope (STM) have been done on a polycrystalline gold film deposited on a glass substrate. The peak-to-peak surface roughness was measured as a function of annealing time after annealing at 170 °C with a special pan-cake furnace in the STM. The gold surface diffusion coefficient at 170 °C can then be extracted from these measurements. 相似文献
12.
N. Sankara Subramanian T. Sornakumar S. Gurumoorthy M. Harihara Sundar P. Vickraman 《Ionics》2007,13(6):461-466
Ceria-stabilized zirconia (CSZ) thin films have been developed over Ni-based alloy substrate by vacuum evaporation method
using an electron beam. X-ray diffraction (XRD) analysis of the film heat treated at different temperatures reveals monoclinic
phase stabilization. Transmission measurements of the films annealed at different temperatures, in the wavelength region 300–1,100 nm,
indicate that the band gap energy of the films lies between 3.6 and 3.8 eV. Refractive index of the films was found to increase
with the increase in the annealing temperature. Micro hardness of the films increases nonlinearly with the increase in annealing
temperature, indicating an improvement in the hardness of the films. Thermal conductivity studies of the CSZ-coated substrate
show a nonlinear decrease with the increase in annealing temperature. Surface investigations of the CSZ films confirm an increase
in grain size and a decrease in surface roughness with the increase in annealing temperature of the films.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
13.
14.
Hydroxyapatite coating on porous silicon substrate obtained by precipitation process 总被引:2,自引:0,他引:2
Chen Shaoqiang Zhu Ziqiang Zhu Jianzhong Zhang Jian Shi Yanling Yu Ke Wang Weiming Wang Xiaohua Feng Xiao Luo Laiqiang Shao Li 《Applied Surface Science》2004,230(1-4):418-424
Hydroxyapatite Ca10(PO4)6(OH)2 (HAP) is known as a bioactive and biocompatible material, HAP coatings were used to improve the biocompatible of substrate by many researcher, In this work, HAP thin films on porous silicon (PS) substrates have been prepared by aqueous precipitation method with rapid thermal annealing (RTA) processes. The HAP films had been prepared under the annealing temperature ranging from 300 to 1000 °C. By the measurement of X-ray diffraction (XRD), it was found that for the crystallinity optimization, the heat-treatment at 850–950 °C for 1 h would be favorable. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements reveal a dense and smooth surface of the HAP film, and tightly adherence of the coating on porous silicon substrate after sintered. Thus, by this method, porous silicon could be increased its bioactivity and so that could be used in the biomedical area. 相似文献
15.
The change of the size distribution of Au clusters induced by annealing was studied in situ by transmission electron microscopy. Starting from statistically distributed Au clusters on a thin amorphous carbon film, “islands” are formed within a few months storage at room temperature, which consist of Au clusters with sizes <4 nm embedded in a thin Au film. These islands cover originally areas with sizes around 25 × 70 nm2. If the temperature is increased in the transmission electron microscope two different processes can be clearly distinguished that lead to the coarsening of the cluster size distribution: cluster coalescence and (contactless) Ostwald ripening. The degree and rate of the coarsening are found to depend on the underlying surface (Au film or amorphous carbon) and the exposure to the high-flux high-energy electron beam, which can be estimated to lead to high-temperature excursions in a cluster on a 10−12 s time scale. The experimental findings are confirmed by Monte-Carlo simulations using the many-body Gupta potentials in order to calculate the Au/Au interaction. Moreover, the results of MC simulations suggest an electron-beam induced formation of a “quasi-two-dimensional gas” of small highly mobile Au species on the Au film, which promotes Ostwald ripening. 相似文献
16.
T. E. Sukhanova P. G. Ulyanov G. G. Vladimirov S. I. Fedoseenko V. K. Adamchuk S. V. Valueva A. Ya. Volkov N. A. Matveeva L. N. Borovikova 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(3):440-446
Morphological characteristics and electronic structures of platinum-containing nanosystems obtained during a redox reaction
in water medium at different concentrations of a stabilizing polymer and platinum were studied by atomic-force microscopy
(AFM), X-ray photoelectron spectroscopy, and dynamic light scattering. It was shown that individual and associated structures
of different morphologies were formed on the silicon substrate surface. Comparison of the dimension characteristics of nanoclusters
in the Pt nanoparticle-polymer systems (in solution by means of molecular optics, on the silicon substrate surface in air
by means of AFM) for ionogenic and nonionogenic polymer matrices upon the change of the mass ratio ν has shown that the nanocluster
sizes in solution are two to three times larger than those in a thin film formed on the substrate surface. The size dependences
of the nanoclusters on ν obtained by these methods exhibit the same character. 相似文献
17.
Melissa A. Holmes Michael E. Mackay Rachel K. Giunta 《Journal of nanoparticle research》2007,9(5):753-763
Addition of fullerenes (C60 or buckyballs) to a linear polymer has been found to eliminate dewetting when a thin (∼50 nm) film is exposed to solvent
vapor. Based on neutron reflectivity measurements, it is found that the fullerenes form a coherent layer approximately 2 nm
thick at the substrate – polymer film interface during the spin-coating process. The thickness and relative fullerene concentration
(∼29 vol%) is not altered during solvent vapor annealing and it is thought this layer forms a solid-like buffer shielding
the adverse van der Waals forces promoted by the underlying substrate. Several polymer films produced by spin- or spray-coating
were tested on both silicon wafers and live surface acoustic wave sensors demonstrating fullerenes stabilize many different
polymer types, prepared by different procedures and on various surfaces. Further, the fullerenes drastically improve sensor
performance since dewetted films produce a sensor that is effectively inoperable. 相似文献
18.
Boryakov A. V. Nikolitchev D. E. Tetelbaum D. I. Belov A. I. Ershov A. V. Mikhaylov A. N. 《Physics of the Solid State》2012,54(2):394-403
The chemical and phase compositions of silicon oxide films with self-assembled nanoclusters prepared by ion implantation of
carbon into SiO
x
(x < 2) suboxide films with subsequent annealing in a nitrogen atmosphere have been investigated using X-ray photoelectron spectroscopy
in combination with depth profiling by ion sputtering. It has been found that the relative concentration of oxygen in the
maximum of the distribution of implanted carbon atoms is decreased, whereas the relative concentration of silicon remains
almost identical over the depth in the layer containing the implanted carbon. The in-depth distributions of carbon and silicon
in different chemical states have been determined. In the regions adjacent to the layer with a maximum carbon content, the
annealing results in the formation of silicon oxide layers, which are close in composition to SiO2 and contain silicon nanocrystals, whereas the implanted layer, in addition to the SiO2 phase, contains silicon oxide species Si2+ and Si3+ with stoichiometric formulas SiO and Si2O3, respectively. The film contains carbon in the form of SiC and elemental carbon phases. The lower limit of the average size
of silicon nanoclusters has been estimated as ∼2 nm. The photoluminescence spectra of the films have been interpreted using
the obtained results. 相似文献
19.
采用XeCl准分子激光对非晶碳化硅(a-SiC)薄膜的脉冲激光晶化特性进行了研究.通过原子力显微镜(AFM)和Raman光谱技术对退火前后薄膜样品的形貌、结构及物相特性进行了分析.结果表明,选用合适的激光能量采用激光退火技术能够实现a-SiC薄膜的纳米晶化.退火薄膜中的纳米颗粒大小随着激光能量密度的增加而增大;Raman谱分析结果显示了退火后的薄膜的晶态结构特性并给出了伴随退火过程存在的物相分凝现象.根据以上结果并结合激光退火特性,对a-SiC的脉冲激光晶化机理进行了讨论.
关键词:
激光退火
晶化
碳化硅 相似文献
20.
W. Deng T. Ohgi H. Nejo D. Fujita 《Applied Physics A: Materials Science & Processing》2001,72(5):595-601
Highly conductive and transparent indium tin oxide (ITO) thin films, each with a thickness of 100 nm, were deposited on glass
and Si(100) by direct current (DC) magnetron sputtering under an argon (Ar) atmosphere using an ITO target composed of 95%
indium oxide and 5% tin oxide for photon-STM use. X-ray diffraction, STM observations, resistivity and transmission measurements
were carried out to study the formation of the films at substrate temperatures between 40 and 400 °C and the effects of thermal
annealing in air between 200 and 400 °C for between1 and 5 h. The film properties were highly dependent on deposition conditions
and on post-deposition film treatment. The films deposited under an Ar atmosphere pressure of ∼1.7×10-3 Torr by DC power sputtering (100 W) at substrate temperatures between 40 and 400 °C exhibited resistivities in the range
3.0–5.7×10-5 Ω m and transmissions in the range 71–79%. After deposition and annealing in air at 300 °C for 1 h, the films showed resistivities
in the range 2.9–4.0×10-5 Ω m and transmissions in the range 78–81%. Resistivity and transmission measurements showed that in order to improve conductive
and transparent properties, 2 h annealing in air at 300 °C was necessary. X-ray diffraction data supported the experimental
measurements of resistivity and transmission on the studies of annealing time. The surface roughness and film uniformity improve
with increasing substrate temperature. STM observations found the ITO films deposited at a substrate temperature of 325 °C,
and up to 400 °C, had domains with crystalline structures. After deposition and annealing in air at 300 °C for 1 h the films
still exhibited similar domains. However, after deposition at substrate temperatures from 40 °C to 300 °C, and annealing in
air at 300 °C for 1 h, the films were shown to be amorphous. More importantly, the STM studies found that the ITO film surfaces
were most likely to break after deposition at a substrate temperature of 325 °C and annealing in air at 300 °C for 2 or 3 h.
Such findings give some inspiration to us in interpreting the effects of annealing on the improvement of conductive and transparent
properties and on the transition of phases. In addition, correlations between the conductive/transparent properties and the
phase transition, the annealing time and the phase transition, and the conductive/transparent properties and the annealing
time have been investigated.
Received: 10 July 2000 / Accepted: 27 October 2000 / Published online: 9 February 2001 相似文献