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将纳米技术与光纤技术相结合,利用改进的化学气相沉积法(MCVD)制作纳米级InP薄膜内包层光纤及在普通单模光纤纤芯中掺杂纳米级InP粒子的新型光纤,前者单位长度放大系数最大达到15.35dB/m,能在较短的长度上对信号光起到放大作用,便于集成化;后者经实验证实其纤芯具有光波导传输性能.两种新型高非线性光纤在光通信器件中的具有应用前景. 相似文献
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分别采用化学气相沉积法和电弧放电法制备了多壁碳纳米管.利用扫描电镜测量了两种不同方法所制备样品的形貌,并在室温下测量了这两种样品的喇曼光谱、吸收光谱和光致发光光谱.结果显示:电弧法所制的纳米管管径较小,且纳米管相互缠绕明显;两种样品的喇曼光谱中均存在D模和G模,但化学气相沉积法制备的碳管的结构更完美,石墨化程度和碳管纯度更高;两种样品都在250 nm处有一个强的吸收峰,当采用共振激发时,两种样品均在480 nm处有带状发射光谱,而用550 nm的光激发时,化学气相沉积法制备的多壁碳纳米管在820 nm处具有光致发光,电弧法制备的样品在此波段则无光致发光. 相似文献
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实现高速沉积对于薄膜微晶硅太阳电池产业化降低成本是一个重要手段.采用超高频等离子体增强化学气相沉积(VHF-PECVD)技术,实现了微晶硅硅薄膜的高速沉积,并通过改变气体总流量改变气体滞留时间,考察了气体滞留时间在化学气相沉积(CVD)过程中对薄膜的生长速率以及光电特性和结构特性的影响.采用沉积速率达到12?/s的高速微晶硅工艺制备微晶硅电池,电池效率达到了5.3%.
关键词:
气体滞留时间
高速沉积
微晶硅
超高频等离子体增强化学气相沉积 相似文献
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介绍了采用了MgB2薄膜的化学气相沉积(CVD)异位退火和双温区混合物理化学气相沉积(HPCVD)制备技术,并以B膜作为势垒层在多晶的Al2O3基底上制作了三明治结构的MgB2/B/MgB2多层膜.采用扫描电子显微镜(SEM)、X射线衍射(XRD)和标准四线法对制备的MgB2/B/MgB2多层膜的断面结构、超导薄膜晶体结构及超导特性进行了测量研究.结果表明,制备的MgB2/B/MgB2多层膜结构清晰,底层和顶层超导薄膜显示出良好的超导特性. 相似文献
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碳氢(cH)及其掺杂材料常被用作ICF实验靶丸烧蚀层材料。制备CH薄膜及其掺杂材料的方法有很多,诸如:离子束辅助沉积、离子溅射沉积、低压等离子体化学气相沉积(LPPCVD)等。近年来,详细研究了LPPCVD法制备CH薄膜的制备方法与工艺,形成了比较成熟的技术路线与工艺路线,并为“神光”实验提供了一系列实验靶丸。 相似文献
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负色散斜率的色散补偿光纤的研制 总被引:4,自引:1,他引:3
对三包层的大负色散、负色散斜率的色散补偿光纤进行了理论研究,分析了各个参量对色散曲线的调节作用,发现色散补偿光纤只有在一定范围的拉丝芯径内,以牺牲负色散数值才能大负色散斜率,采用在光纤拉丝时旋转预制棒的工艺减小了光纤的偏振模色散进一步改进国内已有的的改进的化学汽相沉积(MCVD)光纤生产工艺,研制出了较高水平的色散补偿光纤。 相似文献
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Abstract In order to achieve a high fiber preform production rate, the deposition mechanism in the VAD process has been investigated. The particle-deposition rate was found to depend largely on the Reynolds number value in the flame stream. Based on the flame stream Schlieren observation results, this Reynolds number relationship to the deposition rate can be explained in terms of two fine glass particle-diffusion effects: One is molecular diffusion and the other is eddy diffusion. Finally, by applying such particle-diffusion effects to the actual VAD process, a 4.5 gr/min preform production rate was attained. 相似文献
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Watekar P.R. Goswami M.L.N. Biswas J.C. Acharya H.N. 《Optical and Quantum Electronics》2004,36(5):405-411
The Er-doped double-core dispersion compensating fiber (EDDCF) has been fabricated using modified chemical vapor deposition
(MCVD) technique. We have obtained 14 dB gain at 1550 nm (using a diode laser of 980 nm wavelength which provides 100 mW of
pump power) with dispersion of about −165 ps/km nm. It is useful for the optical fiber network where amplification as well
as negative dispersion is necessary. We are the first to report the experimental realization and characterization of the EDDCF. 相似文献
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H. M. Presby 《Fiber and Integrated Optics》1979,2(2):111-126
The refractive index depression that exists along the axis in modified chemical vapor deposited (MCVD) preforms and fibers doped mainly with GeO2 or P2O5 is studied by interference microscopy. The index profile of a preform, determined as a function of its transition from the uncollapsed to the fully collapsed state, shows that this central region is fully depleted of dopant and has an index value corresponding to that of the pure fused silica cladding. The same results are found in samples taken from six preform tips and from a relatively large fiber, indicating that this effect is a general property of an uncompensated fabrication process. Implications for its influence on the fiber's transmission properties are discussed. 相似文献
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Fufei Pang Xianglong Zeng Zhenyi Chen Tingyun Wang 《Optical and Quantum Electronics》2007,39(12-13):975-981
We fabricated a novel special silica optical fiber doped with nano-semiconductor material InP in double cladding layers by using conventional modified chemical vapor deposition (MCVD) process. During the deposition process, InP powder was placed at the entrance of silica substrate tube and vaporized by high temperature. With the help of nitrogen gas flow, the vaporized InP was carried into silica substrate tube and deposited on the inner surface in the form of nano-particle. The physical structure and amplification characteristics of the special fiber were investigated. From the refractive index distribution of the preform, we can observe obvious increase in inner cladding index, which attributes to InP dopant. By using 532 nm LD as pump, a broadband amplified spontaneous emission (ASE) was demonstrated in the wavelength range from 1,080 to 1,350 nm. The proposed nano- semiconductor doped fiber with optical amplification is expected to a wide application in optical fiber communications. 相似文献
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S. M. Aljamimi M. S. Khairul Anuar S. Z. Muhamad-Yassin M. I. Zulkifli S. Hanif N. Tamchek 《Fiber and Integrated Optics》2014,33(1-2):105-119
AbstractIncorporation of alumina (Al2O3) into a silica matrix by modified chemical vapor deposition and a solution doping technique is investigated in this study. Multiple soaking cycles were used to increase the aluminum content in the core layer. The effect of alumina retention in silica matrix soot is focused by multiple cycles of soaking with different solution concentrations, while the effect of the adsorption mechanism is fixed by maintaining the soot deposition process (such as temperature [1,800°C], precursor, total gas flow, and soaking time). The deposited soot is examined for porosity characteristics and effective surface area by a gas adsorption technique with Brunauer–Emett–Teller surface area analysis and the surface and cross-section morphology using scanning electron microscopy. Three different concentrations are used in this work (0.3, 0.7, and 1.2 M) with multiple cycles of soaking. Sintering and the collapsing process is controlled for each preform. The result shows that the alumina content is increased substantially as the number of soaking processes is increased, which may be due to the retention effect as only a small amount of adsorption process takes place as indicated by the slight decrease in the surface area of soot. The collapsed preforms are analyzed using a preform analyzer. Energy dispersive x-ray spectrometry is used to check aluminum content and distribution into the core layer. 相似文献
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In order to achieve a high fiber preform production rate, the deposition mechanism in the VAD process has been investigated. The particle-deposition rate was found to depend largely on the Reynolds number value in the flame stream. Based on the flame stream Schlieren observation results, this Reynolds number relationship to the deposition rate can be explained in terms of two fine glass particle-diffusion effects: One is molecular diffusion and the other is eddy diffusion. Finally, by applying such particle-diffusion effects to the actual VAD process, a 4.5 gr/min preform production rate was attained. 相似文献
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《Current Applied Physics》2014,14(7):954-959
We report the design and fabrication of an integrated Mach–Zehnder interferometric (MZI) biochip based on silicon oxynitride layers deposited with a plasma-enhanced chemical vapor deposition (PECVD) process. A rib waveguide for an integrated MZI sensor has been designed to have a high surface sensitivity and a single-mode behavior by using an effective index method. The integrated MZI chip operating at 637 nm is fabricated via conventional photolithography and reactive ion etching. As a biosensor application, the real-time and label-free detection of the covalent immobilization and hybridization of DNA strands is performed and verified with this device. 相似文献
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Sn/Yb codoped silica optical fiber preform is prepared by the modified chemical vapor deposition (MCVD) followed by the solution-doping method. Ultraviolet (UV) optical absorption, photoluminescence (PL) spectra under 978-nm laser diode (LD) pumping, and refractive index change after exposure to 266-nm laser pulses are obtained. There is only a little change in the PL spectra while a positive refractive index change up to 2×10^-4 is observed after 30-min exposure to 266-nm laser pulses. The results show that both of the peculiar photosensitivity of Smdoped silica and the gain property of Yb-doped silica fiber are preserved in the Sn/Yb codoped silica optical fiber preform. The experimental data suggest that the photosensitivity of the fiber preform under high energy density laser irradiation should be mainly due to the bond-breaking of oxygen deficient defects, while under relatively low energy density laser irradiation, the refractive index change probably originates from the photoconversion of optically active defects. 相似文献