共查询到20条相似文献,搜索用时 15 毫秒
1.
Anees A. Ansari M. A. M. Khan M. Naziruddin Khan Salman A. Alrokayan M. Alhoshan M. S. Alsalhi 《半导体学报》2011,32(4):043001-6
This paper reports the optical and electrical properties of electrochemically deposited polyaniline (PANI)-cerium oxide (CeO2) hybrid nano-composite film onto indium-tin-oxide (ITO) glass substrate. UV–visible spectroscopy and I-V characteristic were performed to study the optical and electrical parameters of the electrochemically deposited film. The film exhibited a strong absorption below 400 nm (3.10 eV) with a well defined absorbance peak at around 285nm (4.35 eV). The estimated band gap of the CeO2 sample was 3.44 eV and this value is higher than bulk CeO2 powder (Eg = 3.19 eV) due to quantum confinement effect. 相似文献
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研究了退火温度对电子束制备Ag/TiO2薄膜光学 性质和光催化性能的影响。在石英玻璃、硅片 上沉积了Ag/TiO2复合薄膜,在空气氛围下,进行了400℃, 500℃的退火一小时.用紫外-可见分光光度 计、X射线衍射仪(XRD) 、原子力显微镜(AFM)对沉积和退火后的薄膜分别进行光学、结构、 形貌分析。结 果表明:300℃下制备的Ag/TiO2复合薄膜为无定形结构,400℃以上薄呈多晶态。吸光度和表面粗糙度 随退火温度的增加而增大,薄膜的光学带隙随退火温度的增加而减小。锐钛矿相表现出了更 好的光催化性能。 相似文献
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Hyeong-Ho ParkXin Zhang Soon-Won LeeDong-Joo Jeong Sang-Moo LeeKi-don Kim Dae-Geun ChoiJun-Hyuk Choi Jihye LeeEung-Sug Lee Ho Kwan KangHyung-Ho Park Ross H. HillJun-Ho Jeong 《Microelectronic Engineering》2011,88(6):923-928
A direct ultraviolet (UV)-assisted nanoimprinting procedure using photosensitive titanium di-n-butoxide bis(2-ethylhexanoate) is employed in this study for the nanopatterning of anatase titanium dioxide (TiO2) structure. Upon annealing at 400 °C for 1 h, the lateral shrinkage and thickness shrinkage of the TiO2 nanostructure were 39.6% and 52.5%, respectively, which indicated an anisotropic volume loss. During UV irradiation and annealing treatment, the refractive index of UV-irradiated TiO2 film is gradually increased by improvement in the packing density and crystallinity of the film. According to increasing UV exposure time and annealing temperature, the optical band gap (Eg) of UV-irradiated TiO2 film is red-shifted from 3.73 to 3.33 eV due to the formation of lattice defects, vacancies and voids during the photochemical reaction and due to the effect of quantum confinement during annealing treatment. These results suggest that the refractive index and optical Eg of TiO2 nanostructure could be controlled by tuning the UV exposure time and annealing treatment conditions. Nanopatterns of TiO2 fabricated by direct UV-assisted nanoimprint lithography are potential candidates for use in protective coatings for optical mirrors and filters, high-reflectivity mirrors, broadband interference filters and active electro-optical devices where ordered surface nanostructures could be necessary. 相似文献
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TiO2 thin films were deposited using Sol-Gel spin coating technique using titanium isoperoxide as the Titania precursor. The films were characterized using X-ray diffraction, capacitance voltage measurement and Raman characterization technique. The XRD and Raman spectra indicate the presence of anatase TiO2 phase in the film. The grain size as calculated using the Scherrer’s formula was found to be 30, 66 and 59 nm for TiO2(0 0 4), TiO2(2 0 0) and TiO2(2 1 1), respectively. The grain size was found to increase after annealing at 800 °C. The dielectric constant as calculated using capacitance voltage measurement was found to be 25. The refractive index of the film was 2.34. 相似文献
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Xingqi Fu Chunyang JiaXiaolong Weng Jianliang XieLongjiang Deng 《Organic Electronics》2014,15(11):2702-2709
Titanium dioxide (TiO2) nanorods (NRs) array was successfully prepared via hydrothermal method on fluorine doped tinoxide (FTO) coated transparent conductive glass substrate. The hybrid film of polyaniline (PANI)/TiO2 NRs was achieved through electrochemical polymerization of aniline onto the TiO2 NRs array film. The electrochromic and optical properties of the hybrid film were investigated by cyclic voltammetry (CV), amperometric i–t and UV–vis spectroscopy. The results indicate that the hybrid film has long term stability and reversible color changes after cyclic voltammetry scans for 200 circles. The PANI/TiO2 NRs hybrid film can show three different colors. Response time of PANI/TiO2 NRs hybrid film is about 0.7 s and 2.6 s at different states, respectively. The TiO2 NRs array and the loose, porous surface among the hybrid film facilitate charge transmission and also provide large surface area for electrochemical reaction. 相似文献
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原子层沉积(ALD)方法可以制备出高质量薄膜,被认为是可应用于柔性有机电致发光器件(OLED)最有发展前景的薄膜封装技术之一。本文采用原子层沉积(ALD)技术,在低温(80℃)下,研究了Al2O3及TiO2薄膜的生长规律,通过钙膜水汽透过率(WVTR)、薄膜接触角测试等手段,研究了不同堆叠结构的多层Al2O3/TiO2复合封装薄膜的水汽阻隔特性,其中5 nm/5 nm×8 dyads(重复堆叠次数)的Al2O3/TiO2叠层结构薄膜的WVTR达到2.1×10-5 g/m2/day。采用优化后的Al2O3/TiO2叠层结构薄膜对OLED器件进行封装,实验发现封装后的OLED器件在高温高湿条件下展现了较好的寿命特性。 相似文献
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在本文中,采用化学机械抛光(CMP)对TiO2薄膜进行平坦化处理,以降低TiO2薄膜表面粗糙度和提升抛光去除速率。实验基于优化的TiO2薄膜CMP工艺参数,通过研究抛光液组分:硅溶胶浓度、螯合剂和活性剂浓度以及抛光液pH值对材料去除速率和表面粗糙度的影响,获得最佳的抛光液组分。实验结果表明:在磨料SiO2浓度为8 %、螯合剂为10 ml/L、活性剂为50 ml/L,pH = 9.0时,TiO2薄膜材料去除速率(MRR)为65.6 nm/min,表面粗糙度(Ra)为1.26 ?(测试范围: 10 μm×10 μm),既保证了较高去除速率又降低了表面粗糙度。 相似文献
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采用热蒸发法技术沉积Ge34Ga2S64非晶薄膜,并对薄膜样品在375℃热处理2h。通过分光光度计、表面轮廓仪和显微拉曼光谱仪测试热处理前后薄膜样品的透过曲线、薄膜厚度和拉曼结构。利用薄膜干涉曲线的波峰和波谷计算了薄膜的厚度和折射率,并根据Swanepoel方法以及Tauc公式分别计算了薄膜折射率色散曲线和光学带隙等参数。结果表明,Ge34Ga2S64非晶薄膜经热处理后发生热致漂白效应,大分子团簇以及Ge-Ge、S-S同极错键含量明显减少,网络结构无序性降低,从而引起薄膜的光学吸收边蓝移、折射率降低、表面粗糙度(Ra)降低0.515nm和光学带隙增大0.118eV。 相似文献
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Wan-Gee Kim 《Microelectronic Engineering》2009,86(11):2153-2156
The effect of annealing on the resistive switching of 35-nm-thick TiO2 thin film deposited with magnetron sputtering system was studied. Pt and Ag were used as a top electrode (TE), and Pt was used as a bottom electrode (BE). For Pt/as-deposited TiO2/Pt structure, both unipolar (URS) and bipolar resistive switching (BRS) were observed depending on the current compliance level. For Pt/400 °C annealed TiO2/Pt structure, only BRS was observed regardless of the current compliance level. The increase in the work function of the TiO2 film after annealing lowers the potential barrier height and changes the electron transfer process which was also confirmed from Ag/as-deposited TiO2/Pt structure. Above 600 °C, the film becomes leaky with the increase in grain size and roughness and the resistive switching behavior was not observed. 相似文献
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采用溶胶-凝胶旋涂法(Sol-Gel Spin-Coating Method)制备了Al掺杂量为3.00at%,N掺杂量分别为6.00at%,7.00at%,8.00at%和9.00at%的Al/N共掺杂TiO2薄膜样品。对样品测试的结果表明,共掺杂样品依旧保留了TiO2的基本结构,并且Al/N共掺杂样品的晶粒尺寸有不同程度的减小,使样品表面得以修饰,变得更加均匀、平整。共掺杂样品吸收边都出现了不同程度的红移,在紫外光区以及可见光区的吸光性都有所增强。N掺杂量为7.00at%时,(101)衍射峰值最大,峰型最尖锐,所得到的TiO2薄膜的光学性能最好。共掺杂后的样品与本征TiO2相比带隙值都有所减小,且最小值为2.873eV。以上结果表明Al/N共掺杂TiO2薄膜使其光学性能得到了改善。 相似文献
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D. Lenssen R. Carius S. Mesters D. Guggi H. L. Bay S. Mantl 《Microelectronic Engineering》2000,50(1-4):243-248
Recent band structure calculations indicate, that ruthenium silicide (Ru2Si3) is semiconducting with a direct band gap. Electrical measurements lead to a band gap around 0.8 eV which is technologically important for fiber communications. This makes Ru2Si3 a promising candidate for silicon-based optical devices, namely LEDs. We present results on the epitaxial growth of ruthenium silicide films on Si(100) and Si(111) fabricated by the template method, a special molecular beam epitaxy technique. We structurally characterized the films by Rutherford backscattering and ion channeling, X-ray diffraction and transmission electron microscopy. To determine the electrical resistivity at high temperatures films were grown on insulating substrates to prevent parallel conduction through the substrate. Finally we show first results of the optical absorption performed by photothermal deflection spectroscopy indicating pronounced absorption above 1.5 eV. 相似文献
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Debashis Sarmah Juti R. Deka Satyajib Bhattacharyya Nidhi S. Bhattacharyya 《Journal of Electronic Materials》2010,39(10):2359-2365
Low-density polyethylene (LDPE)/titania (TiO2) and polystyrene (PS)/titania (TiO2) composite systems have been developed as alternative substrates for microstrip patch antennas (MPA) for handheld devices.
Morphological, thermal, and microwave characterizations of these composites have been conducted for different volume fractions
of TiO2 in the polymer matrix. The size of the titania particles was found to be of the order of 0.5 μm, and their distribution in the composite was quite uniform. Composite materials showed an improvement in thermal and microwave
properties over the parent polymer. Verification of these composites as potential substrates for MPA was carried out by fabricating
simple rectangular patch X-band antennas. Materials with optimized substrate properties were chosen to design the MPA. The
patches were designed with 4% volume fraction TiO2 in the LDPE composite system and 6% volume fraction TiO2 in the PS composite system. Return loss of ∼18 dB was observed for both systems. 相似文献
15.
Wan-Gee Kim 《Microelectronic Engineering》2010,87(2):98-103
Effect of the top electrode (TE) metal on the resistive switching of (TE)/TiO2/Pt structure was investigated. It was confirmed that the potential barrier height between the metal and TiO2 is an important factor on the resistive switching characteristics. When high Schottky barrier was formed with the TiO2 film, using Pt or Au as a top electrode, both stable URS (unipolar) and BRS (bipolar resistive switching) characteristics were observed depending on the current compliance level. In the case of Ag, which forms a relatively low Schottky barrier, only BRS characteristics were observed, regardless of the current compliance level. In the case of Ni and Al, which have similar work function as Ag, unstable URS and BRS at very low current compliance levels were observed due to a chemical reaction at the interface. For the Ti electrode, resistive switching was not observed, because the work function of Ti is lower than that of TiO2 and TiO phase was formed at the interface (Ti/TiOx contact is ohmic). 相似文献
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Abstract: Surface roughness by peaks and depressions on the surface of titanium dioxide (TiO2) thin film, which was widely used for an antireflection coating of optical systems, caused the extinction coefficient increase and affected the properties of optical system. Chemical mechanical polishing (CMP) is a very important method for surface smoothing. In this polishing experiment, we used self-formulated weakly alkaline slurry. Other process parameters were working pressure, slurry flow rate, head speed, and platen speed. In order to get the best surface roughness (1.16 A, the scanned area was 10 × 10 μm2) and a higher polishing rate (60.8 nm/min), the optimal parameters were: pressure, 1 psi; slurry flow rate, 250 mL/min; polishing head speed, 80 rpm; platen speed, 87 rpm. 相似文献
17.
TiO_2/SiO_2、ZrO_2/SiO_2多层介质膜光学损耗及激光损伤研究 总被引:9,自引:0,他引:9
以TiO_2/SiO_2及ZrO_2/SiO_2多层介质膜为例,测试了不同工艺条件及不同膜系结构下薄膜样品的光学损耗及激光损伤阈值,同时对实验结果作了初步的分析讨论. 相似文献
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The trapping/detrapping behavior of charge carriers in ultrathin SiO2/TiO2 stacked gate dielectric during constant current (CCS) and voltage stressing (CVS) has been investigated. Titanium tetrakis iso-propoxides (TTIP) was used as the organometallic source for the deposition of ultra-thin TiO2 films at low temperature (<200 °C) on strained-Si/relaxed-Si0.8Ge0.2 heterolayers by plasma-enhanced chemical vapor deposition (PECVD) in a microwave (700 W, 2.45 GHz) plasma cavity discharge system at a pressure of 66.67 Pa. Stress-induced leakage current (SILC) through SiO2/TiO2 stacked gate dielectric is modeled by taking into account the inelastic trap-assisted tunneling (ITAT) mechanism via traps located below the conduction band of TiO2 layer. The increase in the gate current density observed during CVS from room temperature up to 125 oC has been analyzed and modeled considering both the buildup of charges in the layer as well as the SILC contribution. Trap generation rate and trap cross-section are extracted. A capture cross-section in the range of 10−19 cm2 as compared to 10−16 cm2 in SiO2 has been observed. A temperature-dependent trap generation rate and defects have also been investigated using time-dependent current density variation during CVS. The time dependence of defect density variation is calculated within the dispersive transport model, assuming that these defects are produced during random hopping transport of positively charge species in the insulating high-k stacked layers. SILC generation kinetics, i.e. defect generation probability under different injected fluences for various high-constant stress voltages in both polarities have been studied. An empirical relation between trap generation probability and applied stress voltage for various injected fluences has been developed. 相似文献