锗硅薄膜的光学特性研究

GeSi薄膜的光学特性可以随内部组分的变化而变化,在光电子集成方面优于GaAs、InP等传统的发光材料,已引起了人们的广泛关注.采用等离子体CVD法在玻璃衬底上沉积GeSi薄膜,研究了不同生长条件下的样品的光学特性,从样品的紫外\|可见光反射谱和透射谱计算出光学带隙,发现随着Ge含量的增加,薄膜的光学带隙减小.并且研究了样品的光学带隙与温度的关系,当GeH4流量为4sccm时,薄膜的光学带隙随温度的升高有一个最小值,当GeH4流量为8sccm时,温度升高而薄膜的光学带隙基本不变.     

CdO - ZnO复合薄膜的光电学特性研究

采用磁控溅射技术制备了不同原子百分比的CdO - ZnO复合薄膜,并利用X射线衍射仪、扫描电子显微镜、紫外可见近红外分光光度计、四探针电阻测试仪研究了薄膜的结构和光电学特性.研究表明:适量增加CdO掺杂量可提高薄膜在近红外区域的透射率; CdO - ZnO复合薄膜的光学带隙和电阻率随CdO含量的增加而减小,且当CdO和ZnO的原子百分比为4:1时薄膜的带隙和电阻率分别为2.09 eV和10.79×10^-3 Ω·cm.该研究结果可为制备高导电性和高透过率的薄膜提供参考.     

溶胶-凝胶法制备掺镧钛酸钡薄膜及其光学性质研究

以硝酸镧、醋酸钡、钛酸四丁酯为原料,采用溶胶一凝胶旋涂法制备掺La的钛酸钡薄膜,研究薄膜的晶体结构、表面形貌、紫外-可见光吸收性能及光学带隙。研究结果表明,纯钛酸钡和掺La钛酸钡薄膜均为单一四方钙钛矿结构,La3＋的引入可以使钛酸钡薄膜在可见光区的透过率和光学带隙有一定程度下降,而退火温度对掺镧钛酸钡薄膜光学带隙基本无...     

纤锌矿和亚稳岩盐矿结构氧化锌的电学光学特性

利用密度泛函赝势法对纤锌矿结构和亚稳岩盐矿结构氧化锌电学和光学特性进行了对比研究,计算表明,亚稳岩盐矿结构氧化锌的电离度下降,对于亚稳岩盐矿结构氧化锌得到的GGA带隙略大于纤锌矿结构氧化锌,两种多形体电学结构的差别导致了光学特性的不同．预测了亚稳岩盐氧化锌具有负的微分电导效应,特别是在施主杂质重掺杂的情况下．强烈的电子-光子的耦合以及宽的光学响应区使它更适合于光学领域的应用,特别是在极短的波段,尽管它具有间接带隙的特性．     

溶胶凝胶法制备LiTaO3薄膜

用溶胶凝胶法在FTO导电玻璃基片上沉积LiTaO₃薄膜,采用TG-DTA、SEM、XRD、UV-Vis光谱法分析薄膜的表面形貌、结晶性能和光学性能。结果表明,650 °C下退火的薄膜具有在(006)晶向上强烈的择优取向性,表面形貌均匀致密,薄膜裂纹减少,杂质LiTa₃O₈峰的半高峰宽和光学带隙E_g明显受到薄膜结晶性能的影响,光学带隙值E_g随着杂质LiTa₃O₈半高峰宽的降低而增加,LiTaO₃薄膜的光学带隙E_g蓝移从3.87 eV增加到3.91 eV。     

氧气气氛对氧化铪薄膜性能的影响

在有氧和无氧气氛条件下,采用真空电子束热蒸发技术在P-Si(100)硅衬底上制备了HfO2薄膜.利用X射线光电子能谱,对薄膜的化学组分进行表 征,利用椭偏法对薄膜的膜厚和折射率进行测定,利用紫外可见光谱测量了薄膜的在200 nm～1 200 nm范围内的光透过率,并计算出其光学能隙,利用C-V测试系统对退火后薄膜的介电性能进行测试.结果表明,有氧和无氧条件下制备的薄膜中组分含量存在明显差异,相比于无氧条件下制备的薄膜,有氧条件下制备的薄膜中含有较少的铪单质,因而在可见光范围内具有较高透光率和光学能隙,较低的折射率和更优异的介电性能.     

快速退火对HfO_2高k薄膜结构和电学性能的影响

文章采用射频反应磁控溅射法在p型Si(100)衬底上制备了HfO2高k薄膜,并对样品进行了N2气氛快速退火处理。对薄膜进行了Raman光谱、UV-VIS-NIR透过光谱、XPS以及C-V特性的分析,研究了快速退火对HfO2薄膜结构、成分、禁带宽度和电学特性的影响。结果表明,HfO2薄膜有良好的非晶稳定性,组分基本符合化学剂量比。经N2气氛快速退火处理后,薄膜的化学剂量比得到改善,禁带宽度增大,且薄膜内的固定电荷密度和平带电压偏移减小。     

退火温度对Al掺杂ZnO薄膜结构和性能的影响

采用直流磁控溅射技术,在玻璃衬底上制备了ZnO:Al(ZAO)薄膜样品。其他参数不变,在不同的温度下对样品进行了退火处理,研究了薄膜的结构性质、电学和光学性质随退火温度的变化关系。实验结果表明:在退火温度为200℃时,ZAO薄膜具有较优的光电性能,其电阻率为9.62×10-5.cm,可见光区平均透射率为89.2%。     

射频磁控溅射制备的CdSe薄膜的光电学性质

采用射频磁控溅射技术在不同溅射功率下制备了CdSe薄膜,并利用X射线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、能量色散X射线光谱仪(EDAX)、紫外可见近红外(UV-VIS-NIR)分光光度计和霍尔效应测试仪研究了溅射功率对薄膜的结构和光电学性质的影响.研究表明：增加溅射功率有利于增强薄膜的结晶性能;随着溅射功率的增加,薄膜的光学带隙和电阻率逐渐减小,载流子浓度逐渐增加,即薄膜的光电性能不断增强.该研究结果可为CdSe薄膜在光电器件方面的应用提供参考.     

掺杂与退火温度对VO2薄膜性能的影响

采用真空蒸发法在普通玻璃表面制备了VO2薄膜,研究了退火温度和掺杂对薄膜表面形貌、晶体结构、电学性能和光学性能的影响.结果表明:经400℃、420℃、450℃、500℃退火得到的VO2薄膜其表面形貌和晶体结构存在明显的差异,其中420℃退火后的薄膜结晶形态良好,主要成分是VO2,在65℃左右表现出明显的电阻突变,常温下在波长1 700 nm附近薄膜的光透过率达59.9％;在VO2薄膜中掺入W6 ,相变温度有所降低,但掺杂使薄膜光透过率降低.     

面向平板结构钙钛矿太阳能电池的金属氧化物综述

作为平板结构钙钛矿太阳能电池的电荷传输层，金属氧化物薄膜对器件性能有重要影响. 系统性概述平板结构钙钛矿太阳能电池对金属氧化物薄膜形貌、电学、光学、化学及热等物理特性要求，并对目前在高效钙钛矿太阳电池制备中最有前景的金属氧化物电子传输层及空穴传输层材料特性及代表性工作进行总结. 针对大多数金属氧化物迁移率低、表面缺陷多及能级匹配差的问题，分析元素掺杂、表面改性、复合薄膜设计等手段解决的相关进展. 总结目前金属氧化物薄膜沉积技术现状及优缺点，探讨今后薄膜沉积技术发展、改进方向. 对低温沉积金属氧化物薄膜在柔性器件方面的应用进行展望.     

快速循环热处理对(Co0.35Fe0.65)99O1薄膜磁性能的影响

针对(Co0.35Fe0.65)99O1薄膜,研究了两种不同热处理工艺对其磁性能的影响。结果表明:快速循环热处理可以改善高磁矩(Co0.35Fe0.65)99O1薄膜磁性能,在450℃几个快速循环热处理后,沉积薄膜的矫顽力从105下降到3 Oe,电阻率下降到70%,a-Fe (Co)相晶粒尺寸可以减小到15~35 nm,该处理方法较以往的热处理更能改善软磁薄膜的性能。     

铝掺杂氧化锌薄膜的电学及光学性能

利用脉冲激光沉积法,在氧气氛下(氧分压为11 Pa)以石英玻璃为基体沉积了铝掺杂氧化锌薄膜。靶材选用锌铝合金靶,沉积过程中基体温度保持在150℃。研究了ZnO薄膜中铝的质量分数与薄膜电学性能和发光性能的关系。结果表明,掺杂铝的质量分数为1.37%时所获得的ZnO薄膜具有最小的电阻率和较强的紫外发光特性。     

Effect of Ag addition on the microstructure and magnetic properties of FePt thin films

FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin films, effects of Ag addition on the structure and properties of FePt thin films were investigated. Proper Ag addition was found helpful for FePt phase transition at lower annealing temperature. With Ag addition, the magnetic domain pattern of FePt thin film changed from maze-like pattern to more discrete island-like domain pattern in [FePt/Ag]n multilayer thin films. In addition, introducing nonmagnetic Ag hindered FePt grains from growing larger. The in-depth defects in FePt films and [FePt/Ag]n multilayer films verify that Ag addition is attributed to a large number of pinning site defects in [FePt/Ag]n film and therefore has effects on its magnetic properties and microstructure.     

Preparation and electrical properties of BaPbO3 thin film

BaPbO3 thin films were deposited on Al2O3 substrates by sol-gel spin-coating and rapid thermal annealing. The microstructure and phase of BaPbO3 thin films were determined by X-ray diffractometry, scanning electrons microscopy and energy dispersive X-ray spectrometry. The influence of annealing temperature and annealing time on sheet resistance of the thin films was investigated. The results show that heat treatment, including annealing temperature and time, causes notable change in molar ratio of Pb to Ba, resulting in the variations of sheet resistance. The variation of electrical properties demonstrates that the surface state of the film changes from two-dimensional behavior to three-dimensional behavior with the increase of film thickness. Crack-free BaPbO3 thin films with grain size of 90 nm can be obtained by a rapid thermal annealing at 700 ℃ for 10 min. And the BaPbO3 films with a thickness of 2.5 μm has a sheet resistance of 35 Ω·-1.     

Effect of Annealing on Structural, Optical and Electrical Properties of CdS Thin Films Grown by ILGAR

CdS thin films were deposited by ILGAR （ ion lay gas reaction） method. The effect of annealing temperature under N2 atmosphere on the structural, chemical, topographical development and optical and electrical properties of CdS thin films was investigated by XRD, SEM, XPS, UV- VIS and two-probe technique. It is found that the cubic-phase of as-deposited CdS film transforms to hexagonal phase with a perfected orientation along （002） plane at 300 ℃ . The band gap decreases with increasing annealing temperature until 300 ℃ , which is consistent with the grain growth. The fall of dark and light resistivitiy is obvious with increasing annealing temperature, corresponding to the continuous grain growth and deviation of stoichiometry at higher temperature. The smooth and uniform surface of as-deposited films becomes rougher through thermal treatment, which is related to grain growth and sublimation of CdS at a higher annealing temperature.     

纳米VO2薄膜相变特性的红外透射表征研究

采用双离子束溅射VOx薄膜附加热处理的方式制备纳米VO2薄膜,利用X射线衍射仪和扫描电子显微镜分别对其结晶结构和表面形貌进行了测试,利用傅立叶变换红外光谱仪(FTIR)对热驱动下纳米VO2薄膜相变过程中的光学性能进行测试与分析。实验结果表明,经400℃N2热处理后,获得了由纳米颗粒组成的VO2薄膜;在所测试的红外波段,纳米VO2薄膜内颗粒发生相变的初始温度随波长的增加而升高,薄膜的相变温度点随波长增加也逐渐升高。 更多还原     

Physical properties of Al-doped ZnO and Ga-doped ZnO thin films prepared by direct current sputtering at room temperature

Al-doped zinc oxide(AZO) and Ga-doped zinc oxide(GZO) thin films with the same doping concentration(3.6 at%) were deposited on glass substrates at room temperature by direct current(DC) magnetron sputtering.Consequently,we comparatively studied the doped thin films on the basis of their structural,morphological,electrical,and optical properties for optoelectronic applications.Both thin films exhibited excellent optical properties with more than 85%transmission in the visible range.The GZO thin film had better crystallinity and smoother surface morphology than the AZO thin film.The conductivity of the GZO thin film was improved compared to that of the AZO thin film:the resistivity decreased from 1.01×10~(-3) to 3.5×10~(-4) Ω cm,which was mostly due to the increase of the carrier concentration from 6.5×10~(20) to 1.46×10~(21)cm~(-3).These results revealed that the GZO thin film had higher quality than the AZO thin film with the same doping concentration for optoelectronic applications.     

Infrared thermochromic properties of VO2 thin films prepared through aqueous sol-gel process

The stoichiometric vanadium(IV) oxide thin films were obtained by controlling the temperature, time and pressure of annealing. The thermochromic phase transition and the IR thermochromic property of 400 nm and 900 nm VO2 thin films in the 7.5 μm-14 μm region were discussed. The derived VO2 thin film samples were characterized by Raman, XRD, XPS, AFM, SEM, and DSC. The resistance and infrared emissivity of VO2 thin films under different temperature were measured, and the thermal images of films were obtained using infrared imager. The results show that the VO2 thin film annealed at 550 ℃ for 10 hours through aqueous sol-gel process is pure and uniform. The 900 nm VO2 thin film exhibits better IR thermochromic property than the 400 nm VO2 thin film. The resistance of 900 nm VO2 film can change by 4 orders of magnitude and the emissivity can change by 0.6 during the phase transition, suggesting the outstanding IR thermochromic property. The derived VO2 thin film can control its infrared radiation intensity and lower its apparent temperature actively when the real temperature increases, which may be applied in the field of energy saving, thermal control and camouflage.