Characterization of organic polymer thin films deposited by rf magnetron sputtering

Organic polymer thin films deposited by sputtering using polytetrafluoroethylene (PTFE) and polyimide (PI) targets were investigated with Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM). Films deposited from the PTFE target were poly-hydro-fluoro-carbon. The thin films showed water repellency with an H₂O contact angle of about 110° and were transparent in the visible region. C-F combination states in the films were similar to those of bulk PTFE. Films deposited from the PI target were found to contain C-N bonds and were harder than bulk PI. The color of thin films was dark brown, showing the existence of C-N bonds, such as those in imide and/or amide groups. However, the combination states characterized by FTIR and XPS analyses were considerably different from those of bulk PI. The difference in chemical composition and combination states between the films deposited from PTFE and PI is thought to result from the difference in types of particles sputtered from the targets; in the case of PTFE sputtering, less C-F bonds are broken by collision of Ar ions for sputtering, whereas in the case of PI sputtering, C-H and C-C bonds are broken by collision of Ar ions.     

沉积时间对磁控反应溅射制备TiO2薄膜性能的影响

应用直流磁控反应溅射法,在玻璃基体上制备了具有光催化活性的TiO2薄膜.TiO2薄膜的厚度随沉积时间的增加而均匀增长.基体温度则在溅射的最初1h很快上升到110℃,溅射7h基体温度不超过130℃.溅射2h得到的是非晶态TiO2薄膜,而溅射3～7h制备的薄膜为锐钛矿型结构.非晶态和小晶粒TiO2薄膜的紫外一可见透射光谱谱带边沿与结晶较好的TiO2薄膜相比有明显的蓝移,薄膜的透射率随沉积时间的增加而下降.钛以四价钛的形式存在于TiO2薄膜中.TiO2薄膜的光催化活性随沉积时间争薄膜厚度的增加而有较大提高.     

氧分压对TiO2膜结构与光学性质的影响

报道了用反应溅射法制备TiO2 膜的实验研究 .详细研究了膜的沉积、膜结构及其光学性质 ,随溅射氧分压的变化 .随氧分压由 6× 10 - 2 Pa增加到 9× 10 - 2 Pa时 ,晶体结构由金红石变到锐钛矿 ,氧分压超过 9× 10 - 2 Pa时趋向于无定形结构 .与膜结构密切相关的折射率n随氧分压的增大由 2 .4 4变到 1.96 ,禁带宽度Eg 则由大变小 ,然后再增大的变化 (3.4 1→ 3.2 6→3.4 2 ) .     

Effect of oxygen flow rate on ITO thin films deposited by facing targets sputtering

Tin-doped indium oxide (ITO) thin films were deposited on glass substrates at various oxygen flow rates using a planar magnetron sputtering system with facing targets. In this system, the strong internal magnets inside the target holders confine the plasma between the targets. High resolution transmission electron microscopy revealed a combination of amorphous and crystalline phases on the glass substrate. X-ray photoelectron spectroscopy suggested that the decrease in carrier concentration and increase in mobility were caused by a decrease in the concentration of Sn⁴⁺ states. The electrical and optical properties of the ITO films were examined by Hall measurements and UV-visible spectroscopy, which showed a film resistivity and transmittance of 4.26 × l0⁻⁴ Ω cm, and > 80% in the visible region, respectively.     

Fabrication of cerium oxide films on sapphire by rf magnetron sputtering

Results are presented of experiments to fabricate preferentially (200) oriented CeO₂ films without mechanical stresses on Al₂O₃ substrates. Pis’ma Zh. Tekh. Fiz. 25, 47–51 (June 12, 1999)     

Thin films prepared by sputtering MgF2 in an rf planar magnetron

Magnesium fluoride granules have been sputtered in an rf planar magnetron at 20 MHz. Films deposited in Ar developed a strong optical absorption at high power levels arising from fluorine depletion and magnesium oxidation. The latter was attributed to a reaction between residual water vapour and the dissociated compound. Films prepared at a low power input with a growth rate of about 2 nm min^?1 had the lowest optical absorption and a refractive index near to that of bulk MgF₂ but their growth was too slow for most practical uses. The magnetron discharge probably resulted in greater target dissociation than a non-magnetron discharge operated at the same power input because of the ion impact localisation at the magnetron target. Film analysis showed that biasing the film substrate positively with respect to ground to enhance impact of fluorine negative ions raised the fluorine content of the film. Sputtering in a CF₄+Ar+O₂ mixture to enhance fluorine sorption by the film and reduce carbon deposition by oxidation was ineffective. The resultant deposit was a fluorocarbon polymer with a low Mg/F content.     

Influence of fabrication parameters on crystallization,microstructure, and surface composition of NbN thin films deposited by rf magnetron sputtering

In this work NbN thin films have been grown by magnetron rf sputtering of a δ-NbN (99.99%) target. In particular, the influence of certain fabrication parameters (substrate temperature, power supplied to the target or additional N₂ flux in the preparation chamber) on the crystallization, microstructure, and surface composition of the deposited films have been studied. The films have been characterized by X-ray diffraction (XRD) at grazing angle in the θ–2θ configuration, scanning electron microscopy (SEM), wavelength dispersive spectrometry (WDS), and X-ray photoelectron spectroscopy (XPS). XRD results show that films grown at a substrate temperature of 573 K and a power supply applied to the target of 300 W present the same crystalline structure of the target while films grown at these temperature and power supply conditions plus the additional presence of N₂ during fabrication, grow highly textured along the plane (200). SEM results indicate that the films present columnar growth and a high homogeneity. WDS analysis shows that films grown at 573 K and 300 W are stoichiometric. XPS shows a complex surface composition of the films most external 5 nm, indicating the presence of niobium nitride (NbN _x ), niobium oxy-nitride (NbN _x O _y ), and niobium oxide (Nb₂O₅).     

Influence of substrate temperature on N-doped ZnO films deposited by RF magnetron sputtering

Nitrogen-doped ZnO films were deposited by RF magnetron sputtering in 75% of N₂ / (Ar + N₂) gas atmosphere. The influence of substrate temperature ranging from room temperature (RT) to 300 °C was analyzed by X-ray diffractometry (XRD), spectrophotometry, X-ray photoelectron spectroscopy (XPS), secondary-ion mass spectrometry (SIMS) and Hall measurements setup. The XRD studies confirmed the hexagonal ZnO structure and showed that the crystallinity of these films increased with increasing substrate temperature (T_s). The optical studies indicate the average visible transmittance in the wavelength ranging 500-800 nm increases with increasing T_s. A minimum transmittance (9.84%) obtained for the films deposited at RT increased with increasing T_s to a maximum of 88.59% at 300 °C (500-800 nm). Furthermore, it was understood that the band gap widens with increasing T_s from 1.99 eV (RT) to 3.30 eV (250 °C). Compositional analyses (XPS and SIMS) confirmed the nitrogen (N) incorporation into the ZnO films and its decreasing concentration with increasing T_s. The negative sign of Hall coefficients confirmed the n-type conducting.     

氧分压对RF磁控溅射ZrO2薄膜生长特性的影响

采用反应射频(RF)磁控溅射法在n型(100)单晶S基片上沉积了ZrO2膜,研究了氧分压与ZrO：薄膜的表面粗糙度和沉积速率、SiO2中间界层的厚度以及ZrO2薄膜的折射率之间关系。结果表明：随着氧分压增高,薄膜的沉积速率降低,表面粗糙度线性地增加;在低的氧分压情况下,Si基片表面的本征SiO2层的厚度增加幅度较小,在高的氧分压情况下,Si基片表面的本征SiO2层的厚度有较大幅度地增加;在O2／Ar混和气氛下,溅射沉积的ZrO2薄膜的折射率受氧分压的影响不显著,而在纯氧气气氛环境下,ZrO2薄膜的折射率明显偏低,薄膜的致密性变差。     

Structural and surface properties of TiO2 thin films doped with neodymium deposited by reactive magnetron sputtering

Thin films were deposited using modified, high energy magnetron sputtering method from Ti-Nd mosaic targets. The amount of neodymium dopant incorporated into two sets of thin films was estimated to be 0.8 and 8.5 at.%, by means of energy dispersive spectroscopy. On the basis of x-ray diffraction method, the type of crystalline structure and crystallites size were evaluated directly after the deposition process and after additional post-process annealing at 800 °C temperature. The influence of annealing on the surface properties was evaluated with the aid of atomic force microscopy. Uniformity of the dopant distribution in titanium dioxide matrix was examined with the aid of secondary ion mass spectroscopy. Additionally, using atomic force microscope, diversification and roughness of the surface was determined. Chemical bonds energy at the surface of TiO₂:Nd thin films was investigated by x-ray photoelectron spectroscopy method. Wettability measurements were performed to determine contact angles, critical surface tensions and surface free energy of prepared coatings. On the basis of performed investigations it was found, that both factors, the amount of neodymium dopant and the post-process annealing, fundamentally influenced the physicochemical properties of prepared thin films.     

Preferentially oriented vanadium nitride films deposited by magnetron sputtering

Because of solid state lubricious properties of vanadium oxides, wear resistant coatings based on nitrides and carbides of that metal are still of interest for research teams. The aim of this report is to show phase composition evolution from metallic vanadium through intermediate phases up to δ-VN phase supersaturated with nitrogen in thin films deposited by reactive, pulsed magnetron sputtering from vanadium target. This analysis is completed by remarks on preferential orientation, lattice constant and crystallite size. Presented work is a part of research on composite hard coatings for woodworking tools where vanadium nitrides and carbides are considered as a component reducing friction.     

Protective YSZ-based thin films deposited by RF magnetron sputtering

Protective Zr(Y)O_2−δ-based films sputter-deposited onto apatite-type lanthanum silicate ceramics were appraised for potential applications in solid oxide fuel cells with silicate-based solid electrolytes, where the performance may suffer from surface decomposition processes in reducing atmospheres. Dense and crystalline coatings were deposited using radio-frequency magnetron sputtering from an yttria-stabilized zirconia target. On the basis of microstructural analysis and profile measurements, a sputtering power of 300 W was selected in order to achieve deposition rates in the range 0.50-0.75 μm/h. The surface morphology studies using an atomic force microscope revealed typical film structures with small (<50 nm) grains. The polarization of model electrochemical cells with cermet anodes comprising Ni, yttria-stabilized zirconia and Ce_0.8Gd_0.2O_2−δ (50:30:20 wt.%), deposited onto the protective zirconia films, was found quite similar to that of copper-zirconia cermets without interlayers, suggesting that the electrochemical reaction is essentially governed by the oxygen anion transfer from zirconia phase and/or hydrogen oxidation in the vicinity of zirconia film surface.     

Copper nitride films deposited by dc reactive magnetron sputtering

Copper nitride (Cu₃N) films were deposited on glass substrates by sputtering of copper target under various substrate temperatures in the range 303–523 K using dc reactive magnetron sputtering. The substrate temperature highly influenced the structural, mechanical, electrical and optical properties of the deposited films. The X-ray diffraction measurements showed that the films were of polycrystalline nature and exhibit preferred orientation of (111) phase of Cu₃N. The microhardness of the films increased from 2.7 to 4.4 GPa with the increase of substrate temperature from 303 to 473 K thereafter decreased to 4.1 GPa at higher temperature of 523 K. The electrical resistivity of the films decreased from 8.7 × 10⁻¹ to 1.1 × 10⁻³ Ωcm and the optical band gap decreased from 1.89 to 1.54 eV with the increase of substrate temperature from 303 to 523 K respectively.     

Effect of substrate temperature on the structure and optical properties of ZnO thin films deposited by reactive rf magnetron sputtering

Zinc Oxide films were deposited on quartz substrates by reactive rf magnetron sputtering of zinc target. The effect of substrate temperature on the crystallinity and band edge luminescence has been studied. The films deposited at 300 °C exhibited the strongest c-axis orientation. AFM and Raman studies indicated that the films deposited at 600 °C possess better overall crystallinity with reduction of optically active defects, leading to strong and narrow PL emission.     

Effects of sputtering power on mechanical properties of Cr films deposited by magnetron sputtering

Abstract

Chromium (Cr) films were deposited on plain carbon steel sheets by dc and rf magnetron sputtering as well as by electroplating. Effects of dc or rf sputtering power on the deposition rate and properties such as, hardness, adhesion strength, surface roughness and corrosion resistance of the Cr films were investigated. X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microcopy (SEM) analyses were performed to investigate the crystal structure, surface roughness, thickness of the Cr films. Salt fog tests were used to evaluate the corrosion resistance of the samples. The deposition rate, hardness and surface roughness of the Cr film deposited by either dc or rf sputtering increase with the increase in sputtering power but the adhesion strength is nearly independent of the sputtering power. The deposition rate, hardness and adhesion strength of the Cr film deposited by dc sputtering are higher than those of the Cr film deposited by rf sputtering, but rf sputtering offers smoother surface and higher corrosion resistance. The sputter deposited Cr film is harder and has a smoother surface than the electroplated one. The sputter deposited Cr film also has higher corrosion resistance than the electroplated one, which may be attributed to the smoother surface of the sputter deposited film.     

非平衡磁控溅射类金刚石碳膜的性能

用非平衡磁控溅射的方法在室温下制备了光滑、均匀、致密的类金刚石(DLC)薄膜,分析和研究了DLC膜的形貌、结构和摩擦特性.结果表明,靶工作电流对DLC膜的沉积有重要的影响.随着工作电流的增大,薄膜的沉积速率增大,薄膜中sp3键的含量增加.薄膜的摩擦系数随着工作电流的增加略有增大,在摩擦的初始阶段,摩擦系数较高,随着摩擦循环次数的增加,摩擦系数逐渐减小,并逐渐趋于稳定.     

Transparent conductive ZnO:B films deposited by magnetron sputtering

This paper focuses on the preparation of boron doped ZnO (ZnO:B) films prepared by nonreactive mid-frequency magnetron sputtering from ceramic target with 2 wt.% doping source. Adjusting power density, ZnO:B film with low resistivity (1.54 × 10^− 3 Ω cm) and high transparency (average transparency from 400 to 1100 nm over 85%) was obtained. Different deposition conditions were introduced as substrate fixed in the target center and hydrogen mediation. Hall mobility increased from 11 to above 26 cm²/V·s, while carrier concentration maintained almost the same, leading to low resistivity of 6.45 × 10^− 4 Ω cm. Transmission spectra of ZnO:B films grown at various growth conditions were determined using a UV-visible-NIR spectrophotometer. An obvious blue-shift of absorption edge was obtained while transmittances between 600 nm and 1100 nm remained almost the same. Optical band baps extracted from transmission spectra showed irregular enhancement due to the Burstein-Moss effect and band gap renormalization. Photoluminescence spectra also showed a gradual increase at UV emission peak due to free exciton transition near band gap. We contributed this enhancement in both optical band gap and UV photoluminescence emission to the lattice structure quality melioration.