Characterization of flexible switchable mirror film prepared by DC magnetron sputtering

An electrochromic switchable mirror on a flexible plastic sheet was developed taking into consideration practical use, low cost and high adaptability. The mirror has a multilayer of Mg₄Ni/Pd/Al/Ta₂O₅/WO₃, which was fabricated by DC magnetron sputtering on an ITO-coated PET sheet. In the previous research, when the mirror was exposed to air for a long period of time, its optical switching properties disappeared. This work focused on the mechanism of degradation of the mirror in different environments. When the mirror was stored in a desiccator for 50 days as a means of preservation, its switching speed was seven times higher as compared with the mirror exposed to air. It is also well known that oxygen and moisture in air easily penetrate PET sheets. The features of the PET sheet strongly affected the durability of the optical switching layer. When the state of the optical switching layer was changed to nonmetallic due to the formation of oxide and hydroxide, the optical switching properties almost disappeared.     

Characteristics of tin oxide-based thin film transistors prepared by DC magnetron sputtering

Here we demonstrate the fabrication of SnO(x) thin-film transistors (TFTs), where SnO(x) thin films are deposited as an active channel layer by DC magnetron sputtering. We analyzed the effects of the oxygen partial pressure ratio and post-deposition heat treatment (PDHT) on the characteristics of the SnO(x) thin films. We found improved performance of the TFTs obtained by using interface modification with the optimized deposition condition of SnO(x) thin films. These results are helpful for fabricating oxide-TFTs, including simple binary oxide semiconductors, as an active channel layer.     

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。     

PZT thin film preparation by pulsed DC magnetron sputtering

Pulsed DC magnetron sputtering was used in this study to prepare lead zirconate titanate (Pb(Zr_xTi_1−x)O₃, PZT) thin films. A single metallic target was used for the deposition onto a Pt/Ti/SiO₂/Si substrate and parameters such as: pulse frequency, duty cycle, O₂/Ar flow ratio controlled so as to analyze the effect of the parameters on thin film deposition rate, crystalline structure and morphology. After the deposition, the thin film was annealed in a rapid thermal annealing (RTA) furnace. The experimental results showed that, when the pulse frequency was in the range of 10 kHz-100 kHz, along with the lowering of frequency and the oxygen argon flow rate ratio, the deposition rate gradually increased and the formation of PZT thin film perovskite phase was enhanced; however, if the oxygen argon flow rate ratio was too high, it caused the PZT thin film to generate a pyrochlore phase. However, when the duty cycle was in the range of 95%-75%, the highest deposition rate and better perovskite phase could be obtained in the range of 75%-80%.     

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.     

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.     

Large phase-transition hysteresis for nanostructured VOx film prepared on ITO conductive glass by DC reactive magnetron sputtering

Nanostructured vanadium oxide (nano-VO_x) films were prepared on indium-tin oxide (ITO) glass substrate at low temperature by means of direct current (DC) reactive magnetron sputtering from pure vanadium target in Ar + O₂ atmosphere. Field emission scanning electron microscope (SEM) reveals that the VO_x film is composed of spheroidal nanoparticles whose diameters are in the range of 20–40 nm. This nano-VO_x film shows a broad hysteresis loop whose width is as large as 41.6 °C. Moreover, the metal-insulator transition (MIT) can also be triggered by Joule heat produced by electrical current through the ITO sublayer. Compared to traditional heating of the sample by heating plate, this Joule heating is more efficient and convenient, which enables potential applications of this nano-VO_x film on ITO conductive glass in compact storage devices.     

直流磁控溅射制备铝薄膜的工艺研究

采用直流磁控溅射方法，以高纯Al为靶材，高纯Ar为溅射气体，在玻璃衬底上成功地制备了铝薄膜，并对铝膜的沉积速率、结构和表面形貌进行了研究。结果表明：A1膜的沉积速率随着溅射功率的增大先几乎呈线性增大而后缓慢增大；随着溅射气压的增加，沉积速率先增大，在一定气压时达到峰值后继续随气压的增大而减小。X射线衍射图谱表明Al膜结构为多晶态；用扫描电子显微镜对薄膜进行表面形貌的观察，溅射功率为2600W，溅射气压为0．4Pa时制备的Al膜较均匀致密。     

靶基距对直流反应磁控溅射制备TiO2薄膜光学性质的影响

应用DC(直流)反应磁控溅射设备在硅基底上制备TiO2薄膜,在固定的电源功率下,氩气流量为42.6 sccm,氧流量为15 sccm,溅射时间为30 min的条件下,通过控制靶基距改变TiO2薄膜的光学性质.应用n&k Analyzer 1200测量,当靶基距增加时薄膜的平均反射率降低,同时反射低谷先短波后长波之后再短波;靶基距对消光系数k影响较大;随着靶基距的增加薄膜的折射率出现了下降的趋势,但当靶基距达到一定的量值时折射率的变化趋于稳定.通过XRD和SEM表征发现,随着靶基距的增加TiO2的晶体结构由金红石相向锐钛矿相转变,薄膜表面的颗粒度大小由粗大变得微小细密.     

靶基距对直流反应磁控溅射制备TiO2薄膜光学性质的影响

应用DC(直流)反应磁控溅射设备在硅基底上制备TiO2薄膜,在固定的电源功率下,氩气流量为42.6 sccm,氧流量为15 sccm,溅射时间为30 min的条件下,通过控制靶基距改变TiO2薄膜的光学性质.应用n&k Analyzer 1200测量,当靶基距增加时薄膜的平均反射率降低,同时反射低谷先短波后长波之后再短波;靶基距对消光系数k影响较大;随着靶基距的增加薄膜的折射率出现了下降的趋势,但当靶基距达到一定的量值时折射率的变化趋于稳定.通过XRD和SEM表征发现,随着靶基距的增加TiO2的晶体结构由金红石相向锐钛矿相转变,薄膜表面的颗粒度大小由粗大变得微小细密.     

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.     

直流反应溅射TiO2薄膜的制备及其性能研究

采用直流反应磁控溅射的方法,溅射高纯钛靶在ITO石英衬底上制备了TiO2薄膜.用XRD、Raman光谱、AFM和紫外-可见光分光光度计分别测试了TiO2薄膜的结构、表面形貌和紫外-可见光透射谱,研究了工艺因素中溅射气压、氧氩比和退火温度对薄膜结构的影响.采用C(胶)/TiO2/ITO三层结构研究了锐钛矿TiO2薄膜的紫外光响应.实验结果表明:较低的溅射气压、合适的氧氩比和较高的退火温度有利于锐钛矿TiO2薄膜的结晶.在2 V的偏压下,锐钛矿TiO2薄膜的紫外光响应上升迟豫时间约为3 s,稳定光电流可达到2.1 mA,对紫外光的灵敏性和稳定的光响应表明TiO2薄膜有可能成为一种新的紫外光探测器材料.     

直流反应溅射TiO2薄膜的制备及其性能研究

采用直流反应磁控溅射的方法,溅射高纯钛靶在ITO石英衬底上制备了TiO2薄膜.用XRD、Raman光谱、AFM和紫外-可见光分光光度计分别测试了TiO2薄膜的结构、表面形貌和紫外-可见光透射谱,研究了工艺因素中溅射气压、氧氩比和退火温度对薄膜结构的影响.采用C(胶)/TiO2/ITO三层结构研究了锐钛矿TiO2薄膜的紫外光响应.实验结果表明较低的溅射气压、合适的氧氩比和较高的退火温度有利于锐钛矿TiO2薄膜的结晶.在2 V的偏压下,锐钛矿TiO2薄膜的紫外光响应上升迟豫时间约为3 s,稳定光电流可达到2.1 mA,对紫外光的灵敏性和稳定的光响应表明TiO2薄膜有可能成为一种新的紫外光探测器材料.     

Fabrication of LiCoO2 thin film cathodes by DC magnetron sputtering method

LiCoO₂ thin films were fabricated on Al substrate by direct current magnetron sputtering method. The effects of Ar/O₂ gas rates and annealing temperatures were investigated. Crystal structures and surface morphologies of the deposited films were investigated by X-ray diffraction, Raman scattering spectroscopy and field emission scanning electron microscopy. The as-deposited LiCoO₂ thin films exhibited amorphous structure. The crystallization starts at the annealing temperature over 400 °C. However, the annealed films have the partially disordered structure without completely ordered crystalline structure even at 600 °C annealing. The electrochemical properties of the LiCoO₂ films were investigated by the charge–discharge and cycle measurements. The 500 °C annealing film has the highest capacity retention rate of 78.2% at 100th cycles.     

Transparent conducting zinc oxide thin film prepared by off-axis rf magnetron sputtering

Highly conducting and transparent ZnO : Al thin films were grown by off-axis rf magnetron sputtering on amorphous silica substrates without any post-deposition annealing. The electrical and optical properties of the films deposited at various substrate temperatures and target to substrate distances were investigated in detail. Optimized ZnO : Al films have conductivity of 2200 S cm^-1 and average transmission in the visible range is higher than 85%. The conductivity and mobility show very little temperature dependence.     

Reactive DC sputter-deposited tantalum oxide thin film for all-solid-state switchable mirror

We have developed an all-solid-state switchable mirror of Mg₄Ni/Pd/Ta₂O₅/WO₃/ITO on glass. Each material of Mg₄Ni, Pd, and Ta₂O₅ in the device acts as an optical switching, a proton injector and a solid electrolyte, respectively. The initial state of the device is a reflective state as a mirror and the state changes to a transparent one by applying voltage. In this work, solid electrolyte of Ta₂O₅ thin film was deposited on the WO₃/ITO/glass substrate by reactive DC magnetron sputtering with Ar/O₂ mixture gases. The effect of Ar/O₂ ratio on the electrochemical property of Ta₂O₅ thin film and the optical switching property of the device were investigated. The film deposited at Ar/O₂ of 4.7 had better electrochemical property than that of other films. The transmittance at a wavelength of 670 nm of the device using Ta₂O₅ thin film deposited at Ar/O₂ of 4.7 was reached from the reflective state of 0.1% to the transparent state of 44% less than 15 s by applying voltage of 5 V. The device showed a stable durability of up to 1000 switching cycles.     

Characterization of CNx films prepared by twinned ECR plasma source enhanced DC magnetron sputtering

The DC discharge of a planar magnetron was enhanced by twinned microwave electron cyclotron resonance plasma source. The magnetic cusp geometry formed in the processing chamber was used for plasma confinement. The sputtering discharge characteristics was investigated and a combined mode of voltage and current was observed at a pressure as low as 0.007 Pa. Carbon nitride thin films were synthesized using this method. Characterization of the films showed that the deposition rate was high, and the films were composed of a single amorphous carbon nitride phase with N/C ratio close to that of C₃N₄, with the bonding mainly of C---N type.     

Investigation of antiperovskite Mn3CuNx film prepared by DC reactive magnetron sputtering

Antiperovskite Mn₃CuN_x film was prepared by dc reactive magnetron sputtering. It is the first time to report an antiperovskite ternary nitride film. The composition and crystal structure were characterized by energy dispersive spectroscope (EDS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). From the XRD pattern, it displays a (1 0 0) preferential orientation. A comparative study on the properties of Mn₃CuN_x film and the bulk sample was presented. The film exhibits an antiferromagnetic to paramagnetic transition around 135 K, similar with the bulk sample. With temperature, the resistivity of the film shows semiconductor-like behavior throughout the measured temperature region, whereas there is an abrupt drop around the magnetic transition for the bulk. The variable temperature XRD results indicate that the film did not display any structure transition and shows a normal linear thermal expansion property around the magnetic transition.     

基底结构对纳米铜膜光电性能影响

采用射频磁控溅射法,在涤纶机织布、纺粘非织造布、针织布、纤维膜表面沉积纳米铜薄膜,并用紫外-可见分光光度计与四探针测试仪测试样品透光和导电性能,用彩色摄像机观察溅射样品的表面形貌,用毛管流动孔隙仪测试不同基底孔隙大小及分布,并对结果进行比较分析。结果表明,基底布表面结构形貌与孔隙大小对样品光透射率、导电性能均产生影响。随基底布孔隙率的增加,样品透射率提高,导电性能减弱,针织布由于其松散的线圈结构使得其表面电阻难以测知。