193 nm氟化物增透膜的特性

 为了研制低损耗、高性能的193 nm氟化物增透膜,研究了基底和不同氟化物材料组合对氟化物增透膜的影响。在熔石英基底上,将挡板法和预镀层技术相结合,采用热舟蒸发方式制备了不同氟化物材料组合增透膜,对增透膜的剩余反射率和光学损耗等光学特性,以及表面粗糙度和应力等特性进行了测量和比较。在分析比较和优化的基础上,设计制备的3层1/4波长规整膜系AlF3/LaF3增透膜在193 nm的剩余反射率低于0.14%,单面镀膜增透膜的透射率为93.85%,增透膜表面均方根粗糙度为0.979 nm,总的损耗约为6％。要得到高性能的193 nm增透膜,应选用超级抛光基底。     

CdS纳米粒子的自组装单分子膜制备研究

利用疏基乙酸与草酸的混合自组装单分子膜成功制备了粒径分布均匀的CdS纳米粒子，并用SEM，XRD，XPS，PL对样品进行了表征。SEM表明形成在自组装单分子膜表面上的CdS纳米粒子的平均粒径约为45nm。XPS表明在自组装单分子膜表面形成了CdS纳米粒子。PL谱表明CdS纳米粒子在675nm有一峰值波长，我们认为这一发光是由表面缺陷造成的。     

Fe3O4纳米粒子对P3HT:PCBM电池的影响

为了提高太阳能电池的性能,研究磁性纳米粒子在外加磁场的作用下对聚合物太阳能电池有源层P3HT:PCBM成膜及太阳能电池性能的影响。本文采用热分解法制备了磁性Fe₃O₄纳米粒子,将不同质量分数的Fe₃O₄纳米粒子掺入到P3HT:PCBM溶液中,旋涂后在外加磁场的作用下自组成膜。通过TEM、XRD对制备的Fe₃O₄纳米粒子进行表征,并利用偏光显微镜、原子力显微镜对成膜质量进行探究。结果表明,采用热分解法制备的Fe₃O₄纳米粒子直径在10 nm左右,在外加磁场作用下,Fe₃O₄纳米粒子对成膜有一定的调控作用。当Fe₃O₄纳米粒子掺杂质量分数为1%时,太阳能电池器件的开路电压增加3.77%,短路电流增加24.93%,光电转换效率提高7.82%。     

基于PS球刻蚀技术制备纳米孔滤波器结构的优化分析

金属纳米孔阵列作为彩色滤波器件在OLED中有很好的应用前景。本文提出利用胶体晶体刻蚀与真空沉积技术制作大面积金属纳米孔阵列滤波器,并用FDTD模拟优化所需要加工的金属孔阵列的结构参数,分析了其滤波效果及其物理规律和机制。研究表明:在选择粒径为720 nm的PS球、刻蚀剩余粒径为240nm、金属膜厚度为120 nm的条件下,满足CIE红光显示标准的共振波长为704.06 nm,强度透射率为52%,透射谱带宽为24.8 nm。模拟结果为用PS球刻蚀技术制备金属纳米孔阵列的实验提供了理论支持。     

纳米TiO_2颗粒强化CO_2吸收的研究

本文研究了纳米TiO_2颗粒对碳酸丙烯酯(PC)吸收CO_2的影响,并基于输运机理、微对流机理,建立了三维非稳态多粒子双机理模型对实验结果进行预测。研究表明:纳米流体的黏度随着颗粒纳米颗粒粒径越小,增强因子越大固含量的增大而增大;增强因子随着颗粒固含量的增大先增大后减小,存在最佳固含量;颗粒固含量较小时,相同固含量,纳米颗粒粒径越小,增强因子越大;颗粒固含量较大时,相同固含量,纳米颗粒粒径越大,增强因子越大;随着纳米颗粒粒径的增大,最佳固含量逐渐增大;模型计算值与实验值符合的较好,模型可以预测实验结果。     

可见与红外双波段宽带增透膜的研制

根据军用光学仪器的使用要求,在多光谱ZnS基底上镀制增透膜,要求薄膜在可见与近红外波段400～1000 nm及远红外波段7～11 μm的平均透射率均大于90%.采用电子束真空镀膜的方法并加以离子辅助沉积系统,通过选择ZnS和YbF3作为高低折射率材料,利用最新OptilLayer软件三大模块的功能辅助,调整镀膜工艺参数,改进监控方法,减少膜厚控制误差,在多光谱ZnS基底上成功镀制符合使用要求的增透膜.所镀膜层在可见与近红外波段400～1000 nm的平均透射率大于91%,远红外波段7～11μm的平均透射率大于90%,能够承受恶劣的环境测试,完全满足军用光学仪器的使用要求.     

基于傅里叶模方法的KDP晶体镀膜减反技术

 采用傅里叶模方法,分析了单点金刚石铣削后KDP晶体表面小尺度波纹的周期和幅值对单层增透膜折射率、厚度以及透射率的影响。研究表明：膜层最佳折射率在1.22左右,在此折射率条件下,保证透射率大于99%的单层增透膜的理想厚度范围应为180~220 nm,并且折射率和膜厚值的选取基本不受晶体表面小尺度波纹周期和幅值的影响。若只考虑SPDT法加工后KDP晶体表面小尺度波纹周期和幅值的实际范围,透射率基本不受波纹周期的影响,但却会随波纹幅值的增大而加速下降。理想镀膜条件下透射率最大值大于99%,并且通常在99.67%~99.94%之间。     

纳米Pt-Au合金修饰电极对鲁米诺电化学发光的增敏研究

用化学还原法制备了不同比例及不同粒径的纳米Au-Pt合金,并用UV-Vis、TEM、激光粒径、XRD等方法进行了表征,确认所合成物质确系双金属合金纳米粒子而非两种金属纳米粒子的混合物,通过改变合成方法和条件,可以得到一系列不同含量比和粒径,粒径范围在4.025～92.33 nm之间。采用电化学沉积法可将所制备合金修饰到铂盘电极上,在碱性介质(pH 12)中,随着合金比例的改变和合金粒径的减小,鲁米诺的电化学发光强度显著增强,当合金中Pt∶Au=6∶1,粒子粒径为最小时,所获得修饰电极上鲁米诺的电化学发光强度较裸电极增强近1个数量级。     

纳米晶Ti薄膜的结构研究

用高密度、高电离度的电子迴旋共振等离子体溅射方法在室温基片上沉积出纳米晶Ti薄膜,基体为玻璃、NaCl单晶、纯Al等。对Ti薄膜的结构、形貌和成分进行X射线衍射(XRD),透射电子显微镜(TEM)和X射线光电子能谱(XPS)分析,表明所沉积的Ti薄膜是平均粒径d<10nm,晶粒大小均匀且具有比较稳定的fcc反常结构的纳米晶粒膜。我们还较系统地研究了各工作参数对Ti薄膜的晶体结构、晶粒尺寸、成膜速率以及对基体粘附力的影响,分析了成膜机理。 关键词：     

多层增透薄膜透射特性仿真分析

基于多层薄膜的组成特性,建立了可见光波段以氧化铪和二氧化硅为高、低折射率材料的多层增透膜模型,计算机仿真结果表明:当膜层为单层膜时,其中心透射率为17.31%,通带宽度为102nm;而当膜层增至十一层和二十一层时,其中心透射率分别达到了99.30%和99.99%,但其通带宽度却分别下降至57.1nm和50.2nm.研究表明:随着膜层的不断增加,膜系的透射率也在逐渐增加,且透射率增加的趋势随着膜层数增加而变缓,峰值透射波长缓慢减小,通带半宽度也逐渐变小.     

Antireflective structures via spin casting of polymer latex

Introducing nanosized pores can greatly reduce the refractive index of thin films. Thus antireflective structures can be fabricated by controlled assembly of nanoparticles to form a nanoporous layer. We report what we believe to be the first example of preparing antireflective coatings on glass slides by spin casting polymer latex. Optical transmittances at 550 nm of 95.7% for a single-sided coating and 99.5% for a double-sided coating were achieved. Structure investigations with atomic force microscopy and scanning electron microscopy revealed that the antireflective coatings were highly porous and affected by spin speed and by the concentration and particle size of PMMA latex. Spin coating may be a better method for mass production, because of its convenience, low cost, and good reproducibility.     

Sol-gel preparation of a silica antireflective coating with enhanced hydrophobicity and optical stability in vacuum

A new silica antireflective coating with improved hydrophobicity and optical stability in a vacuum is obtained by a two-step route. Firstly, silica sols are prepared with a sol-gel process, in which tetraethyl orthosilicate is utilized as a precursor. And by introduction of fluorine containing glycol into the sols,the porosity of silica particles and surface polarity of the coatings are decreased. Afterward, coatings are constructed with low surface roughness by modification of PMBA-PMMA. The coatings retain transmission of up to 99.6%, and laser damage threshold of about 50 J/cm2at a wavelength of 532 nm(1-on-1, 10 ns).     

改性剂对旋转法SiO2减反膜均匀性的影响

 分析了采用旋转涂膜法制备溶胶-凝胶SiO₂减反膜过程中条纹缺陷产生的机理,利用含氟醇类试剂对减反膜溶胶进行改性,使溶胶链段柔顺性及流动性得到改善。在光学显微镜下对改性前后的膜层进行了对比和分析,对膜层的表面形貌、表面粗糙度以及透射比等特性进行了表征。结果表明:溶胶改性之后的膜层未出现条纹缺陷,表面粗糙度均方根值从4.55 nm下降到小于1.00 nm,膜层表面质量有了较大提高;改性前后膜层的增透性能相当,在熔石英基片上制备的膜层峰值透射比为99.60%~99.89%,膜层激光损伤阈值为21.0~25.3 J/cm²。     

短波段光学减反膜的溶胶-凝胶法制备及性能分析

 随着大型激光器的发展，对短波段减反膜的要求日益提高，其中钕玻璃激光三倍频（355nm）的减反射成为新的技术要点。采用溶胶-凝胶工艺合成SiO₂溶胶，采用提拉镀膜法制备纳米多孔SiO₂薄膜，薄膜厚度为75nm，折射率控制在1.22，镀制在石英基底上的薄膜其355nm波长的反射率仅为0.2%。通过氨处理工艺和薄膜的表面修饰，薄膜的抗磨擦性能和疏水性能大大提高，薄膜经过蘸有灰尘、乙醇的棉花球擦洗20次和50次后，透射率最大值仅分别降低0.13% 和 0.39%，与水珠的接触角达到110°。     

旋涂法制备KDP晶体减反膜

对KDP晶体旋转涂膜过程中的技术问题进行了探讨,包括元件夹持安全性、膜层均匀性、膜层透射比、膜层疏水性能、膜层激光损伤阈值等。分析了晶体元件加速旋转阶段的受力情况,明确了KDP晶体元件在旋涂操作过程中受力状态的安全性。对不同溶剂体系的膜层均匀性进行了判断,在400 mm尺寸的元件上获得了透射比均匀性为0.3%的减反膜。对溶胶进行稳态剪切流变分析得知,在现有的涂膜转速 (对应剪切速率100~200 s-1)范围内,其粘度随着剪切速率的增加几乎不变,近似牛顿流体。在旋涂过程中,处于基底不同位置的溶胶的粘度大致相等,这是影响膜层均匀性的重要原因之一。膜层疏水性能较好,水接触角测试结果大于152。在SiO2基底上制备的减反膜,1053 nm处透射比大于99.8%。在熔石英基片上制备的三倍频减反膜样品的功能性激光损伤阈值约为10 J/cm2（355 nm, 3 ns）。     

聚乙烯醇/二氧化硅复合增透膜的制备和可清除性

 用溶胶-凝胶法制备了易清洗的聚乙烯醇/二氧化硅(PVA/SiO₂)复合增透膜。先在K9玻璃基片上镀制PVA薄膜,然后在PVA薄膜上镀上二氧化硅增透膜。用紫外可见光分光光度计、椭偏仪、光学显微镜、扫描探针显微镜和静滴接触角测量仪分别分析了膜层和基片的透射率、膜层厚度和折射率、表面形貌、水接触角等性质,用去离子水作溶剂对复合膜层进行清洗。结果表明：聚乙烯醇/二氧化硅复合增透膜峰值透射率达到99.8％,峰值透射率位置可以随SiO₂厚度而调节。复合膜层能够被热水清除,清除后基片完好,其透射率、表面形貌和水接触角与镀膜前一致。     

溶胶—凝胶法制备高强度二氧化硅增透膜的研究

以正硅酸乙酯（ＴＥＯＳ）为原料，用溶胶－凝胶（ＳＯＬ－ＧＥＬ）法在碱性催化条件下制睾一氧化硅膜，经氨气氛和热处理工艺，提高了二氧化硅透膜的拭和抗氙灯辐照能力，可用于激光器泵浦光学元件的增透。在５７０－８００ｎｍ范围内，双面涂的Ｋ９下班的平均透过率可提高到９８％以上。     

Surface modification on a glass surface with a combination technique of sol-gel and air brushing processes

This study fabricated the large area and optically transparent superhydrophobic silica based films on glass surface with optimized hardness. A silane coupling agent, tetraethoxysilane (TEOS), effectively bonds silica particles onto the glass substrate. Desired surface roughness was obtained by adjusting nano silica particles concentration of the precursors prepared by the sol-gel process. Silica suspension was coated onto the glass substrate by the air brushing methods. This method can deposit a uniform, transparent coating on the glass substrate efficiently. Diluting the precursor by adding ethanol or a mixture of D.I. water and ethanol further improved the transmittance and superhydrophobicity efficiency. The results showed that as the silica particle concentration and the thickness of the coating were increased, the surface roughness was enhanced. Rougher surface displayed a higher superhydrophobicity and lower transmittance. Therefore, the concentration of silica particle, volume of coatings, and the ratio of ethanol and D.I. water are of great importance to deposit a transparent, superhydrophobic coating on glass.     

Improved performance of a crystalline silicon solar cell based on ZnO/PS anti-reflection coating layers

A porous silicon (PS) layer was prepared by photoelectrochemical etching (PECE), and a zinc oxide (ZnO) film was deposited on a PS layer using a radio frequency (RF) sputtering system. The surface morphology of the PS and ZnO/PS layers was characterised using scanning electron microscopy (SEM). Nano-pores were produced in the PS layer with an average diameter of 5.7 nm, which increased the porosity to 91%. X-ray diffraction (XRD) of the ZnO/PS layers shows that the ZnO film is highly oriented along the c-axis perpendicular to the PS layer. The average crystallite size of the PS and ZnO/PS layers are 17.06 and 17.94 nm, respectively. The photoluminescence (PL) emission spectra of the ZnO/PS layers present three emission peaks, two peaks located at 387.5 and 605 nm due to the ZnO nanocrystalline film and a third located at 637.5 nm due to nanocrystalline PS. Raman measurements of the ZnO/PS layers were performed at room temperature (RT) and indicate that a high-quality ZnO nanocrystalline film was formed. Optical reflectance for all the layers was obtained using an optical reflectometer. The lowest effective reflectance was obtained for the ZnO/PS layers. The fabrication of crystalline silicon (c-Si) solar cells based on the ZnO/PS anti-reflection coating (ARC) layers was performed. The I–V characteristics of the solar cells were studied under 100 mW/cm² illumination conditions. The ZnO/PS layers were found to be an excellent ARC and to exhibit exceptional light-trapping at wavelengths ranging from 400 to 1000 nm, which led to a high efficiency of the c-Si solar cell of 18.15%. The ZnO/PS ARC layers enhance and increase the efficiency of the c-Si solar cell. In this paper, the fabrication processes of the c-Si solar cell with ZnO/PS ARC layers are an attractive and promising technique to produce high-efficiency and low-cost of c-Si solar cells.     

Preparation of monodisperse polystyrene/silica core-shell nano-composite abrasive with controllable size and its chemical mechanical polishing performance on copper

Monodisperse silica-coated polystyrene (PS) nano-composite abrasives with controllable size were prepared via a two-step process. Monodisperse positively charged PS colloids were synthesized via polymerization of styrene by using a cationic initiator. In the subsequent coating process, silica formed shell on the surfaces of core PS particles via the ammonia-catalyzed hydrolysis and condensation of tetraethoxysilane. Neither centrifugation/water wash/redispersion cycle process nor surface modification or addition surfactant was needed in the whole process. The morphology of the abrasives was characterized by scanning electron microscope. Transmission electron microscope and energy dispersive X-ray analysis results indicated that silica layer was successfully coated onto the surfaces of PS particles. Composite abrasive has a core-shell structure and smooth surface. The chemical mechanical polishing performances of the composite abrasive and conventional colloidal silica abrasive on blanket copper wafers were investigated. The root mean square roughness decreases from 4.27 nm to 0.56 nm using composite abrasive. The PS/SiO₂ core-shell composite abrasives exhibited little higher material removal rate than silica abrasives.