Co类空心球阵列的制备及其光学性能调节

采用磁控溅射的方法,在单层胶体晶体模板上合成了具有六方周期性排列的Co类空心球纳米阵列,并对其结构和光学性能进行了表征和测试。其光学吸收峰与类空心球壳结构的几何参数密切相关:如随着类空心球尺寸的变化,可以实现吸收峰位在几百纳米内的大范围调节(770~1 270nm);而球壳厚度的变化,又可以实现吸收峰位在几十纳米内的精细调节。类空心球结构的周期及球壳厚度,可以通过选择适当的胶体晶体模板(600~1 000nm)及磁控溅射沉积时间来调控。该结构及其特殊的光学性能使其在光学器件、光子晶体及传感器等方面具有重要的应用前景。     

大功率射频板条CO_2激光器电极波导介质膜研究

针对高功率射频板条CO2激光器铜电极表面放电氧化、受射频放电的电子溅射,致使电极表面不光滑,辉光放电不均匀,光波导损耗严重等问题。利用Al2O3波导介质膜具有的反常色散效应、耐高温能力强的特点,采用磁控溅射镀膜技术对激光器电极表面先镀Al,而后阳极氧化获得Al2O3波导介质膜。分析了磁控溅射工艺对膜层结构的影响,测量了镀膜电极对CO2激光的反射率,并进行了放电实验检测。结果表明,溅射功率为250 W时可得到致密的镀膜层结构;厚度6μm的Al2O3薄膜,对波长10.6μm的CO2激光波导反射率最高达75%;电极镀膜后激光器输出功率在占空比为30%时为700 W,占空比为60%时达到了1300 W。     

磁控溅射Ti膜对AZ91镁合金耐磨耐蚀性能的影响

目的通过表面镀Ti膜提高AZ91镁合金的耐磨性能。方法通过直流磁控溅射方法在AZ91镁合金表面镀Ti膜,用拉伸实验法在电子万能实验机上测定薄膜的附着强度,用原子力显微镜观察薄膜与基体的界面形貌,并分析不同溅射参数时膜基的结合能力。通过湿摩擦实验分析两种试样的耐磨性能,采用Js M-670l F冷场发射型扫描电子显微镜观测两种试样磨损后的表面形貌。采用动电位极化曲线测试装置测得两试样的极化曲线,从而判定其耐腐蚀能力。结果通过直流磁控溅射方法制备的Ti膜和AZ91镁合金基体的结合能力与溅射时间有关,当溅射时间为6 min时,膜基结合能力最佳,但结合其他两项参数,所制备试样采用的时间应为4 min。AZ91镁合金镀Ti膜后磨损率降低,腐蚀电流降低,腐蚀电位升高。结论直流磁控溅射方法镀Ti膜提高了AZ91镁合金的耐磨耐蚀性能。     

锆合金表面磁控溅射与多弧离子镀Cr涂层的高温抗氧化性能

为了研究磁控溅射(MS)和多弧离子镀(MAIP)技术制备Cr涂层的高温抗氧化性能,分别在锆合金表面制备厚度约5μm的Cr涂层。利用氧化动力学曲线对比研究800℃条件下涂层的高温抗氧化性能,利用SEM、XRD、EDS分析涂层表面形貌和相结构。结果表明:磁控溅射和多弧离子镀Cr涂层均能显著提高锆合金的高温抗氧化性能;磁控溅射Cr涂层表面光滑、致密,但涂层表面存在一定数量的孔洞,占涂层表面积0.40%,氧化7 h后涂层表面出现裂纹,单位面积氧化增重6.434 mg/cm2;与磁控溅射Cr涂层相比,多弧离子镀Cr涂层不再有(211)单一择优取向,Cr涂层厚度均匀,表面平整,膜/基界面分明,孔洞相对较少,占涂层表面积0.21%,氧化7 h后涂层表面依然致密,单位面积氧化增重5.616 mg/cm2,高温抗氧化性能优于磁控溅射Cr涂层。     

High power impulse magnetron sputtered p-type γ-titanium monoxide films: Effects of substrate bias and post-annealing on microstructure characteristics and optoelectrical properties

In view of wide potential use as p-type oxide semiconductor of titanium monoxide (TiO), it is deposited in this work by using high power impulse magnetron sputtering (HIPIMS), which is known to provide less hysteresis effect in reactive sputtering and better control in stoichiometry. A strong correlation among the preparation parameters on the microstructure and optoelectrical characteristics of the obtained Ti-O films are investigated.Experimental results show that the crystallinic cubic γ-TiO can be directly grown on unheated glass substrate. In regard to the effects of substrate bias and post-annealing, the as-grown γ-TiO transfers into rutile (R-TiO₂) at a critical substrate bias voltage of −125 V or post-annealing temperature of 500 °C. For the purpose of p-type channel layer in transistor, the optimum γ-TiO film exhibiting a high hole mobility of 8.2 cm²/V s is grown at the substrate bias voltage of −25 V and followed by the post-annealing at 400 °C.     

Facile synthesis of three‐dimensional graphene networks by magnetron sputtering for supercapacitor electrode

Three‐dimensional (3D) graphene network deposition on Ni foam without any conductive agents and polymer binders was successfully synthesized by radio frequency magnetron sputtering at low temperature. The direct and close contact between graphene and Ni foam is beneficial to the enhanced conductivity of the electrode, as well as the improvement of ion diffusion/transport into the electrode. As a result, the 3D graphene network deposition on Ni foam electrode delivered a high specific capacitance of 122.0 F g⁻¹ at 1.0 A g⁻¹ and excellent cycle stability with capacitance retention of 99.0% after 1000 charge–discharge cycles. The work shows a new way to facile synthesis of 3D graphene network for various applications in the future. Copyright © 2016 John Wiley & Sons, Ltd.     

Influence of N2 introduction on structural and optical properties of V-doped ZnO thin films grown by low-temperature reactive RF magnetron sputtering

The influences of N₂ introduction to a sputtering gas on structural and optical properties of vanadium-doped ZnO (VZO) films, grown by using reactive RF magnetron sputtering on a quartz substrate at room temperature, were investigated. In the VZO films, V doping caused to form a large number of O vacancies (V_O) and degraded both the c-axis orientation and optical transmittance. While, on the contrary, the ZnO(002) diffraction intensity of 3.5-at.% VZO films increased adding N₂ with a partial pressure ratio (α_N2) >2% reaching a maximum at α_N2 =5%. The average optical transmittance (wavelengths: 450−800 nm) of the 3.5-at.% VZO films was also improved by the N₂ introduction and reached 74% at α_N2 =5%. As a result of the analyses of the chemical binding states of the incorporated N atoms via the Raman spectroscopy and XPS, it was confirmed that the O sites were substituted by the N atoms and the amount of incorporated N increased by the high V doping. From the above, the N₂ introduction was effective to suppress the V_O formation even in room-temperature-grown VZO films, so it enables to improve both the c-axis orientation and optical transmittance.     

Expanded Polystyrene Foam Formed from Polystyrene Beads Coated with a Nanocrystalline SiO2 Film and the Analysis of Its Moisture Adsorption and Resistance to Mechanical Stress

Conventional expanded polystyrene can absorb moisture, which significantly degrades its properties. In the present study, it was demonstrated that SiO₂ can be deposited on polystyrene beads before pre-expansion and molding steps. Under the applied test conditions, expanded polystyrene with nanocrystalline SiO₂ additives had approximately 10% lower moisture adsorption and an 8.4% better resistance to deformation. Expanded polystyrene analysis suggested that the observed improvements were caused by the hydrophobic nature of nanocrystalline SiO₂ and, even more importantly, because SiO₂ acted as an amalgamation catalyst and significantly increased adhesion between the expanded polystyrene beads during the expanded polystyrene molding process.     

磁控溅射制备ITO薄膜光电性能的研究

采用直流磁控溅射方法在玻璃基底上制备了ITO薄膜.分别用分光光度计和四探针仪测试了所制备ITO薄膜在可见光区域内的透过率和电阻率,研究了溅射气压、氧氩流量比和溅射功率三个工艺参数对ITO薄膜光电性能的影响.研究结果表明,制备ITO薄膜的最佳工艺参数为:溅射气压0.6 Pa,氧氩流量比1:40,溅射功率108 W.采用此工艺参数制备的ITO薄膜在可见光区平均透过率为81.18％,薄膜电阻率为8.9197×10-3Ω·cm.