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1.
辛煜  狄小莲  虞一青  宁兆元 《物理学报》2006,55(7):3494-3500
基于单组多匝线圈的小腔体感应耦合等离子体,研究了线圈配置与耦合效率等之间的关联,并将实验结果应用到多组并联螺旋天线感应耦合等离子体放电体系中.采用了改进的朗谬尔探针方法对单源和多源感应耦合等离子体的电参量分别进行了表征.结果表明,使用多螺旋天线并联方式可以产生低气压高密度的感应耦合等离子体放电,通过调整工艺参量,可以将等离子体密度和光刻胶的刻蚀均匀性控制在80%以上. 关键词: 多源感应耦合等离子体 朗谬尔探针 等离子体灰化  相似文献   

2.
首次自行研制了导通电流可达100kA的微秒导通时间POS(等离子体断路开关),并初步开展了等离子体源参数,包括等离子体枪与主回路之间的触发延时、等离子体枪的工作电压以及等离子体枪的数目对开关性能的影响规律研究。  相似文献   

3.
 毛细管放电等离子体是近年来发展起来的一种新型脉冲高能粒子源,可以产生高温、高密和高速等离子体射流,具有推进、发射、加速等功能,可以加热或引燃化学工质,具有广泛的应用前景。介绍了毛细管等离子体的基本原理和特点,综述了国内外研究现状,对毛细管等离子体应用前景进行了展望,以期引起我国对这一技术研究的重视,促进毛细管等离子体技术的发展。  相似文献   

4.
给出了一种感应耦合等离子体源的设计,用于等离子体中和枪装置.通过实验方法研究等离子体源的电子引出特性,并结合理论分析了等离子体密度随射频功率的变化关系.研究结果表明等离子体源的电子引出特性与放电腔内气压有关联性,E?H模式转换中电子密度的变化与负载的电感值相关.研究成果对等离子体中和枪的发展有重要的参考价值.  相似文献   

5.
通过测量脉冲磁过滤阴极弧等离子体沉积系统中的基片台悬浮电位,发现了弧源接地方式对基片台悬浮电位与等离子体电位影响很大。当阳极接地时基片台悬浮电位可达-60V,而弧源悬浮时却只有-5V。因此,要获得相似沉积条件的沉积薄膜,弧源接地方式不同,给基片施加偏压也应有所不同。  相似文献   

6.
介绍一种矩形反应腔体结构的表面波等离子体源,通过对垫层介质及天线结构的优化设计,产生了大面积均匀的等离子体.采用静电探针测量了等离子体参数(密度,电子温度)在不同运行条件(气压,功率)下的空间分布;采用扩散模型,数值模拟了等离子体密度在垂直方向上的空间分布,并比较好地解释了实验测量结果. 关键词: 表面波等离子体 狭缝天线 数值模拟 探针测量  相似文献   

7.
林景全 《物理》1998,27(7):431-434
分析了常规金属靶激光等离子体源产生固体碎屑的原因及其对软X射线光学元件的危害,介绍了近年来发展起来的无碎屑激光等离子体软X射线源,归纳了无碎屑激光等离子体软X射线源的几种形式和特点,并且描述了这种新型光源在软X射线显微术及光刻术中的应用.  相似文献   

8.
在KT—5C装置上用高输出能力的宽频带功率源驱动静电探针调制等离子体湍流振动,研究了等离子体边界湍流扰动的传播特性。在实验中用静电探针和磁探针探测到该功率源驱动的扰动沿磁力线传播,得出湍流扰动既可通过静电涨落形式传播,又可通过电磁落落选径传播。  相似文献   

9.
狄小莲  辛煜  宁兆元 《物理学报》2006,55(10):5311-5317
基于感应耦合等离子体的变压器模型,分析了感应耦合等离子体的功率耦合效率与线圈配置(几何尺寸、电学参量)及等离子体基本参量(等离子体电子密度、电子-中性粒子有效碰撞频率)之间的关系;然后,改变平板型线圈的匝数从而改变了线圈的几何尺寸、电学参量,并且测量出了不同的线圈所对应的功率耦合效率.实验结果表明,线圈的电感量是能否实现放电的决定性因素;而功率耦合效率则与感应线圈的Q值、放电参量(气压、功率)等密切相关,射频输入功率的增加、放电气压的上升都会导致感应耦合等离子体耦合效率的提高,这与感应耦合等离子体的变压器模型预测结果是符合的. 然而,变压器模型给出的提高线圈Q值可导致耦合效率增强的预测结果仅适用于同等电感量的线圈条件. 本文对于单线圈的感应耦合等离子体源的研究为线圈的优化设计甚至大面积的多线圈感应耦合等离子体源研制提供了理论依据. 关键词: 感应耦合等离子体 功率耦合效率 变压器模型  相似文献   

10.
研究了氮氧源大气压等离子体射流对表面大肠杆菌灭活作用,分析了氮氧源大气压等离子体射流的光谱性质。结果表明,在放电电压为6.8kV,气体流速为4L?min?1,处理3min时,氮氧比为1:4的大气压等离子体射流对大肠杆菌的灭活率达到98.4%,接近氧气源大气压等离子体射流灭菌效果。通过大气压等离子体射流发射光谱(OES)分析了氮氧源大气压等离子体射流中活性物质,进而解释大肠杆菌微生物灭活机理,认为NO?γ、OI、?OH等活性物质在表面大肠杆菌灭活过程中起到了重要作用。这将为大气压氮氧等离子体射流在环境卫生、微生物灭活等方面的应用研究提供实验基础和技术支持。  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

13.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

14.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

15.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

16.
17.
We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.  相似文献   

18.
Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.  相似文献   

19.
A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.  相似文献   

20.
Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.  相似文献   

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