Titanium-doped indium oxide films prepared by d.c. magnetron sputtering using ceramic target

Polycrystalline thin films of Ti-doped indium oxide (indium–titanium-oxide, ITiO) were prepared by d.c. magnetron sputtering and their electrical and optical properties were investigated. Doping of Ti was effective in improvement of the electroconductivity of the indium oxide: the electrical resistivity of 1.7 × 10⁻³ Ω cm of non-doping decreased to minimum value of 1.8 × 10⁻⁴ Ω cm at 2.4 at.% Ti-doping when the films were deposited at 300 °C. The polycrystalline ITiO films of 0.8–1.6 at. % Ti-doping showed the high Hall mobilitiy (82–90 cm² V⁻¹ s⁻¹) and the relatively low carrier density (2.4–3.5 × 10²⁰ cm⁻³) resulting in characteristics of both low resistivity (2.1–3.0 × 10⁻⁴ Ω cm) and high transmittance in the near-infrared region (over 80% at 1550 nm), which cannot be shown in the conventional Sn-doped indium oxide (ITO) films.     

Al-Mg-B thin films prepared by magnetron sputtering

Hard, nanocomposite aluminum magnesium boride thin films were prepared on Si (100) substrates with a three target magnetron sputtering system. The films were characterized by X-ray diffraction, atomic force microscope, electron micro-probe, Fourier transform infrared spectroscopy and nanoindentation. The results show that the maximum hardness of the as-deposited films is about 30.7 GPa and these films are all X-ray amorphous with smooth surfaces. The influences of substrate temperature and boron sputtering power on the quality of the films are discussed. From the results of this work, magnetron sputtering is a promising method to deposit Al-Mg-B thin films.     

直流磁控溅射制备TiNxOy薄膜的性能研究

利用直流磁控溅射技术在玻璃衬底上制备了TiNxOy薄膜样品,研究了溅射过程中电压与N2流量之间的迟滞效应,通过X射线衍射（XRD）、UV-Vis分光光度计、四探针电阻仪等测试手段表征了样品的物相、光吸收谱、电阻等性能。结果表明：随着N2含量的提高和薄膜厚度的增加,XRD显示薄膜样品出现明显的衍射峰,吸收光谱向可见光方向展宽至500nm,电阻随着N2含量的提高呈逐渐下降的趋势。     

RF reactive magnetron sputtering for Fe-doped titania films deposited from ceramic targets

Fe-doped titania films are prepared by RF magnetron sputtering on Si wafers with specifically designed TiO₂ targets containing different amounts of Fe₂O₃ powder as a dopant source. The physical properties of the films are investigated in terms of the preparation conditions, such as Fe₂O₃ content in the target, RF power, substrate temperature and working pressure. The films show the typical crystallographic orientation. The growth rate increases with increasing RF power, but decreases with working pressure. Films with 40 nm and the transmittance over 90% at the visible region are prepared by using Fe-doped titania target.     

Structural analysis of amorphous Si films prepared by magnetron sputtering

A study is presented on the structural changes occurring in thin amorphous silicon (a-Si) during thermal treatments. The a-Si films were deposited on single-crystalline Si substrates held at room temperature by magnetron sputtering of a Si target in pure Ar atmosphere, and therefore the films were hydrogen-free. All samples were annealed in vacuum and subsequently studied by electron paramagnetic resonance (EPR) and grazing incidence X-ray diffraction (GIXRD). A slight increase in the dangling bonds content at lower annealing temperatures, and then a strong increase of it at around 650 °C, suggested significant structural changes. The samples were also studied by grazing incidence small-angle X-ray scattering (GISAXS) which confirmed changes at the nanometric scale attributed to voids in the material. A nice correlation of the results of the three techniques shows advantages of this approach in the analysis of structural changes in a-Si material.     

磁控溅射Ni-Mn-Ga薄膜的磁致应变

采用直流磁控溅射的方法,在NaCl基底上沉积了Ni-Mn-Ga薄膜,对薄膜进行了形貌观察、微区成分及结构分析,并测量了薄膜的磁致应变.结果表明,薄膜表面可见大小不一的团簇颗粒,具有明显的岛状结构,表明Ni-Mn-Ga薄膜的形成为典型的核生长型机制.热处理前的薄膜具有部分非晶存在,热处理后薄膜晶化为多晶形态.无约束薄膜在磁场下呈现负的磁致应变,在1.3T磁场下,其最大应变值可达-0.008%,并且可以完全恢复.     

Biomineralization capability of adherent bio-glass films prepared by magnetron sputtering

Radiofrequency magnetron sputtering deposition at low temperature (150°C) was used to deposit bioactive glass coatings onto titanium substrates. Three different working atmospheres were used: Ar 100%, Ar + 7%O₂, and Ar + 20%O₂. The preliminary adhesion tests (pull-out) produced excellent adhesion values (~75 MPa) for the as-deposited bio-glass films. Bioactivity tests in simulated body fluid were carried out for 30 days. SEM–EDS, XRD and FTIR measurements were performed. The tests clearly showed strong bioactive features for all the prepared films. The best biomineralization capability, expressed by the thickest chemically grown carbonated hydroxyapatite layer, was obtained for the bio-glass coating sputtered in a reactive atmosphere with 7% O₂.     

Ellipsometry study of InN thin films prepared by magnetron sputtering

Indium nitride (InN) thin films have been deposited on Si(1 0 0) substrates at temperature of 100–400 °C by reactive radio frequency (RF) magnetron sputtering. We measured the ellipsometric spectra of the InN film samples, and obtained the optical constants for the wavelength range of 410–1100 nm. The absorption edge of the InN films is 1.85–1.90 eV. The thicknesses of various InN films are found to be dependent on the substrate temperature.     

Residual stress in polytetrafluoroethylene-metal nanocomposite films prepared by magnetron sputtering

In the present research we have evaluated residual stress as well as thermal stability of polytetrafluoroethylene (PTFE) and PTFE-based silver (Ag) nanocomposite films fabricated by dual magnetron sputtering. We used a RF magnetron system for sputtering PTFE, and a DC magnetron sputter source for metal. We have demonstrated that thin nanocomposite films of Ag/sputtered PTFE (thickness 800 to 1100 nm, Ag concentration 3.5 to 24.5%) deposited on silicon are stressed (6.24 to 12.2 MPa). The residual stress depends on the concentration of the nanoparticles. Pure sputter deposited PTFE films are under a small tensile stress, which becomes increasingly more compressive upon increasing the filling factor of the metallic nanoparticles. Depending on the concentration of nanoparticles, the residual stress is determined by a thermal component that is sensitive to temperature variation, even in the range of room temperature. In the evaluation of the thermal response of the nanocomposite-silicon system, both the changes in the thermal expansion coefficient as well as the elastic modulus of the nanocomposite with the concentration should be taken into account.     

磁控溅射ITO薄膜的退火处理

采用直流磁控溅射方法在室温下玻璃基板上制备ITO(Indium tin oxide)薄膜,并在真空中不同温度(100℃~400℃)下退火处理.研究了退火对薄膜表面形貌、电光特性的影响.XRD测试发现薄膜在200℃退火后结晶,优选晶向为(222).随退火温度升高,方块电阻迅速下降,表面更加平整,薄膜在可见光范围平均透过率提高到85%.     

Amorphous indium tungsten oxide films prepared by DC magnetron sputtering

Indium-tungsten-oxide (IWO) films were prepared by dc magnetron sputtering at ambient substrate temperature (T_s). Characteristics of the films were compared with those of In₂O₃–SnO₂ (ITO) thin films prepared under the same condition. The sputter-deposited IWO films have entirely amorphous structure with an average transmittance of over 85% in the visible range and exhibit a minimum resistivity of 3.2 × 10^–4cm at W content [W/(In + W)] of 0.57 at.%. An in-situ heating X-ray diffraction measurement have shown that the crystallization temperature of IWO films is higher than those of ITO films (150–160C) and increases with increasing W content. This enabled a smooth amorphous surface of IWO films as compared with a rough surface of partially crystallized ITO films as revealed by an atomic force microscopy. IWO films are useful for transparent electrode of organic light emitting diode and polymer LCDs because of the low resistivity, high transparency and smooth surface obtainable by the conventional dc magnetron sputtering at room temperature.     

Properties of zirconia thin films prepared by reactive magnetron sputtering

The search for alternative dielectric materials with high dielectric constant, thermodynamic stable on silicon substrate and low direct tunneling current leads to oxide based materials like zirconia. Zirconia thin films were prepared by reactive magnetron sputtering. The capacitance voltage, ac and dc electrical characteristics were investigated and the values like fixed oxide charges were calculated and compared among the samples with and without annealing. Films annealed at 700 °C showed a dielectric constant ∼ 26 with interface trap densities of 1.629 × 10¹² eV^− 1 cm^− 2.     

直流反应磁控溅射在3003铝箔表面制备薄膜的研究

为有效提高3003铝箔表面光泽度、比面积及强硬度,采用直流反应磁控溅射的方法.在一定溅射参数条件下,选用高纯钼靶和钛靶对3003铝箔进行溅射实验,分别在铝箔表面主要沉积出AlMo3、Al3Mo薄膜和TiAl、(Ti,Al)N薄膜,利用X射线衍射、扫描电镜分析相组成及微观组织结构,并测试了显微硬度和薄膜厚度,实验结果表明:制备出的AlMo3、Al3Mo薄膜和TiAl薄膜结晶良好,与基底结合良好,铝箔表面美观漂亮、硬度增高及比表面积得到一定提高.     

Inclining columnar structure in Co-Cr films prepared by roll magnetron sputtering

Co-Cr films, sputtered onto continuously transported substrates, exhibit columnar structure bowing according to incident angle variation during deposition. Surface grains were found to be elongated along the substrate moving direction. This factor seems to be related with the relative film motion. The column inclination is well approximated by the incident angle of the atom beam vector sum, considering the incidence probability from the two line target sources. It was found, by analysing the surface grain shapes using a high speed image processor, that the Co-Cr grains exhibited a sharp normal probability distribution in regard to diameter.     

Electrical characterisation of AlCuMo thin films prepared by DC magnetron sputtering

Thin film resistors have been manufactured to evaluate the electrical performance characteristics of AlCuMo thin films. The films were prepared on Al2O3 substrates at room temperature as a function of Mo concentration by DC magnetron sputtering and were then annealed at various temperatures in air and N2 atmospheres. The effect of annealing temperature on the electrical properties of the films was systematically investigated. Increase in Mo content produced a decrease in temperature coefficient of resistance (TCR), an increase in resistivity (r) and an improvement in long term stability (DV/V) of the films. TCR varied from negative to positive and further improvements in resistance stability of the films were also achieved through increasing annealing temperature in both air and N2 atmospheres. A temperature region is proposed where `near zero? TCR (ppm/8C) and long term stability of better than 0.2% can be realised.     

Structural properties of Eu-doped GaN films prepared by RF magnetron sputtering

Films of Eu-doped GaN (GaN:Eu) were grown on c-plane of sapphire (c-Al₂O₃), GaAs(1 0 0), Si(1 0 0) and glass substrates by RF magnetron sputtering method. The X-ray diffraction (XRD) measurement of the sputtered film was carried out. For GaN:Eu and undoped GaN, the lattice constants c and a of as-grown films were larger than those of the bulk GaN. After annealing, the lattice constants c and a of the films decreased.     

On the structure and surface chemical composition of indium-tin oxide films prepared by long-throw magnetron sputtering

Structures and surface chemical composition of indium tin oxide (ITO) thin films prepared by long-throw radio-frequency magnetron sputtering technique have been investigated. The ITO films were deposited on glass substrates using a 20 cm target-to-substrate distance in a pure argon sputtering environment. X-ray diffraction results showed that an increase in substrate temperature resulted in ITO structure evolution from amorphous to polycrystalline. Field-emission scanning electron microscopy micrographs suggested that the ITO films were free of bombardment of energetic particles since the microstructures of the films exhibited a smaller grain size and no sub-grain boundary could be observed. The surface composition of the ITO films was characterized by X-ray photoelectron spectroscopy (XPS). Oxygen atoms in both amorphous and crystalline ITO structures were observed from O 1 s XPS spectra. However, the peak of the oxygen atoms in amorphous ITO phase could only be found in samples prepared at low substrate temperatures. Its relative peak area decreased drastically when substrate temperatures were larger than 200 °C. In addition, a composition analysis from the XPS results revealed that the films deposited at low substrate temperatures contained high concentration of oxygen at the film surfaces. The oxygen-rich surfaces can be attributed to hydrolysis reactions of indium oxides, especially when large amount of the amorphous ITO were developed near the film surfaces.     

Nanostructured ZnTe films prepared by D.C. magnetron sputtering

ZnTe films in nanostructured form have been deposited by high pressure d.c. magnetron sputtering of a ZnTe target onto different substrates kept at various temperatures ranging from 223–373 K. Shift of the band gap to higher energies depended on the relative magnitudes of substrate temperature and gas pressure during deposition.     

Characterization of CuAlO2 films prepared by dc reactive magnetron sputtering

Thin films of copper aluminum oxide (CuAlO₂) were prepared on glass substrates by dc magnetron sputtering at a substrate temperature of 523 K under various oxygen partial pressures in the range 1 × 10⁻⁴–3 × 10⁻³ mbar. The dependence of cathode potential on the oxygen partial pressure was explained in terms of oxidation of the sputtering target. The influence of oxygen partial pressure on the structural, electrical and optical properties was systematically studied. p-Type CuAlO₂ films with polycrystalline nature, electrical resistivity of 3.1 Ω cm, Hall mobility of 13.1 cm² V⁻¹ s⁻¹ and optical band gap of 3.54 eV were obtained at an oxygen partial pressure of 6 × 10⁻⁴ mbar.