2011 Abstracts IEEE International Conference on Plasma Science最新文献_第8页

Study of plasma in bias pluse duty ratio at ICP etch chamber ICP蚀刻室中偏置脉冲占空比等离子体的研究

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993306

T. Jo, M. Yun, BuII Jeon, GwangSup Cho, G. Kwon, Jang-Hoon Choi, Dong-Jin Kim, Chang-Kil Nam

引用次数: 0

Optical characterization of atmospheric torch operating modes 大气火炬操作模式的光学特性

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993140

A. Mcwilliams, S. Shannon, S. Hudak, J. Cuomo

引用次数: 0

Minimizing damage of porous SiCOH using He/H2 plasmas 利用He/H2等离子体减少多孔SiCOH的损伤

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993187

J. Shoeb, M. Kushner

引用次数: 4

Wideband fast wave amplifiers 宽带快波放大器

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5992992

C. Whyte, C. Robertson, K. Ronald, A. Young, W. He, A. Cross, P. Macinnes, A. Phelps

{"title":"Wideband fast wave amplifiers","authors":"C. Whyte, C. Robertson, K. Ronald, A. Young, W. He, A. Cross, P. Macinnes, A. Phelps","doi":"10.1109/PLASMA.2011.5992992","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5992992","url":null,"abstract":"In a number of applications, wideband amplifiers1–5 provide significant advantages over oscillators of similar output power. For instance, in spherical tokamak fusion plasma heating, frequency agility allows targeted heating of specific plasma layers, possibly providing an additional plasma stabilization technique. Experimental and theoretical investigations of wideband amplifiers at MW power levels in the centimeter to millimeter wavelength range have shown that devices with greater than 20% bandwidth, suitable for long pulse to CW operation are a practical proposition. In cases where the ultimate in amplifier bandwidth is required, reversed guide magnetic field Free Electron Maser (FEM) amplifiers5 have demonstrated tunability over 70% of center frequency with 40% instantaneous bandwidth. Gyro-amplifiers1–4 using helically corrugated waveguides6 have shown exceptional gain, power, bandwidth and efficiency performance at cm and mm wavelengths. In all cases, the performance of a long pulse (and therefore high vacuum) system is strongly influenced by factors other than the intrinsic bandwidth of the interaction. For example, the stability of all of these devices can be greatly enhanced by appropriate control of the radiation polarization. However, polarization converters work optimally at only one frequency with declining efficiency at frequencies far from the center frequency. Also low reflection windows with 40% bandwidth for circularly polarized radiation require innovative design solutions. When the design must also be compatible with 500°C bakeout it becomes even more difficult.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128324795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design, construction and first tests of a stainless steel load for high power MM-wave radiation 高功率毫米波辐射不锈钢负载的设计、建造和首次测试

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993174

S. Illy, G. Gantenbein, M. Schmid, J. Weggen

{"title":"Design, construction and first tests of a stainless steel load for high power MM-wave radiation","authors":"S. Illy, G. Gantenbein, M. Schmid, J. Weggen","doi":"10.1109/PLASMA.2011.5993174","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5993174","url":null,"abstract":"The load is a critical and essential component of a test stand for high-power CW gyrotrons. It both has to absorb and to measure the microwave power in an accurate and reliable way. Up to now cylindrical loads with ceramic coating have been operated at KIT/IHM, which show a good absorption behavior and are capable to absorb up to 1MW of microwave power. Unfortunately this type of load has the drawback that the ceramic layer may degrade and even may flake off due to local overheating. To avoid this problem, a load has been designed and constructed that is purely made of stainless steel. Due to the relatively low absorption rate of this material, we had to enlarge the total absorbing surface of this device by inserting an additional structure made of U-shaped stainless steel pipes. Preliminary measurements with a load without any active cooling have shown that 700kW of microwave radiation with a pulse length of two seconds could be absorbed under atmospheric pressure using a 1MW, 140GHz CW series gyrotron for W7-X as source. During the measurement sequence, the load heated up to temperatures of 100°C at the outer surface and up to 250°C at the inner structure which is a critical value in terms of arcing. In the experiments a water-cooled pre-load showed that the reflected power is approximately 2%, which is considered a very good value.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"35 18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132073503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

NX-3 plasma focus device: High flux pulsed neutron source NX-3等离子体聚焦装置:高通量脉冲中子源

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993202

R. Verma, T. L. Tan, P. Lee, A. Talebitaher, H. Shariff, S. V. Springham, A. Shyam, R. Rawat

{"title":"NX-3 plasma focus device: High flux pulsed neutron source","authors":"R. Verma, T. L. Tan, P. Lee, A. Talebitaher, H. Shariff, S. V. Springham, A. Shyam, R. Rawat","doi":"10.1109/PLASMA.2011.5993202","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5993202","url":null,"abstract":"Preliminary experimental results of a new, high energy, dense plasma focus device NX-3 that has recently been made operational at Plasma Radiation Source Lab, NIE, Nanyang Technological University, Singapore is reported. The NX-3 capacitor bank stores 20kJ energy in eight modules (of 2.5kJ each) and cumulatively delivers peak current in the range of 200kA to 600kA (depending upon load and operating parameters) in a quarter time period of ∼3.5µs. In the recent investigations, at ∼10kJ operation, the average neutron yield has been found to be in the order of 109 neutrons/pulse in 4πsr., for the deuterium filling gas pressure range of 6 to 8mbar. Both the time integrated and time resolved techniques are employed simultaneously to study the neutron emission characteristics of this novel device. For the time integrated measurements of neutron yield, 3He proportional counter has been used. The time resolved measurements have been done using plastic scintillator photomultiplier detectors placed at different angular positions. Detailed characterization experiments at higher energies are presently underway and will be reported in the conference.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122556520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Time resolved visible spectroscopy characterizations of single wire aluminum plasmas 单线铝等离子体的时间分辨可见光谱特性

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5992918

K. Blesener, S. Pikuz, T. Shelkovenko, D. Hammer, Y. Maron, V. Bernshtam, L. Weingarten

{"title":"Time resolved visible spectroscopy characterizations of single wire aluminum plasmas","authors":"K. Blesener, S. Pikuz, T. Shelkovenko, D. Hammer, Y. Maron, V. Bernshtam, L. Weingarten","doi":"10.1109/PLASMA.2011.5992918","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5992918","url":null,"abstract":"The conditions within plasmas generated by current-driven explosions of single 15–50µm aluminum (Al) wires are being investigated using time-resolved emission spectroscopy at visible wavelengths. The experiments are being carried out at Cornell University on the 10kA, 500ns rise time Low Current Pulser 3 (LCP3). The plasma parameters being determined as a function of time and radial position include electron temperature and density, ionization state and magnetic field. To determine the magnetic field, a new diagnostic method is being developed which makes use of Zeeman-effect-produced differences in the line shapes of two fine structure components of a multiplet that are equally broadened by both Stark effect and Doppler broadening. This method has been demonstrated at the Weizmann Institute of Science (WSI) in laser-produced plasmas [1] with lower energy densities than are being studied here. As in the work at WSI, we use the Al III [4s–4p] transitions at 5696Å and 5722Å to determine the magnitude of the magnetic field. In the experimental plasmas generated by LCP3, electron number densities are in the range 1017–1018cm−3 while electron temperatures are between 2 and 5eV. Under these conditions, seen close to peak current 300 µm away from the wire, the line broadening due to a magnetic field of 6.5 T is calculated to be 3.0 Å while the Stark broadening at 1018/cm3 is calculated to be 3.5 Å; the Doppler broadening is negligible. The total FWHM difference of the doublet lines resulting from these mechanisms is estimated to be 10%. We are setting up a new spectroscopic system capable of clearly detecting this difference after carrying out preliminary experiments on a lower resolution system. Initial high-resolution data will be presented.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"156 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121048753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical and laboratory investigation of astrophysical cyclotron emission processes 天体物理回旋辐射过程的数值和实验室研究

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993120

D. Speirs, K. Ronald, K. Gillespie, S. McConville, A. Phelps, A. Cross, R. A. Cairns, I. Vorgul, R. Bingham, B. Kellett

{"title":"Numerical and laboratory investigation of astrophysical cyclotron emission processes","authors":"D. Speirs, K. Ronald, K. Gillespie, S. McConville, A. Phelps, A. Cross, R. A. Cairns, I. Vorgul, R. Bingham, B. Kellett","doi":"10.1109/PLASMA.2011.5993120","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5993120","url":null,"abstract":"There are numerous types of astrophysical radio emission in association with non-uniform magnetic fields that have been the subject of particular interest and debate over the last thirty years [1]. Such sources, including planetary and stellar auroral radio emission are spectrally well defined with a high degree of extraordinary (X-mode) polarisation. In particular, for the terrestrial auroral case it is now widely accepted that such emissions are generated by an electron cyclotron-maser instability driven by a horseshoe shaped electron velocity distribution [2,3] formed through magnetic compression. Experiments have been conducted at the University of Strathclyde investigating the electrodynamics of an electron beam subject to significant magnetic compression within a bounding waveguide structure [4]. More recently, a background plasma of variable density has been introduced to the interaction region of the laboratory experiment through use of a Penning discharge geometry [5]. Corroboratory simulations have been conducted using the PiC code VORPAL to investigate the cyclotron emission process in the presence of a background plasma of variable density. The dynamics of the emission mechanism will be discussed for both bounded and unbounded interaction scenarios as a function of ωce / ωpe in line with recent laboratory experiments [5] and earlier numerical simulations of unconstrained electron-cyclotron emission [6].","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121422634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of pre-pulses on extreme ultraviolet conversion efficiency in laser-produced tin plasmas 预脉冲对激光锡等离子体极紫外转换效率的影响

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993265

J. Freeman, R. W. Coons, S. S. Harilal, S. Hassan, A. Hassanein

{"title":"Effects of pre-pulses on extreme ultraviolet conversion efficiency in laser-produced tin plasmas","authors":"J. Freeman, R. W. Coons, S. S. Harilal, S. Hassan, A. Hassanein","doi":"10.1109/PLASMA.2011.5993265","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5993265","url":null,"abstract":"Extreme ultraviolet (EUV) lithography is being considered for manufacturing the next generation of computer chips. However, a suitable source for EUV emission at 13.5 nm must be identified. The source must be able to provide reliable, clean, and powerful EUV emission at 13.5 nm with 2% bandwidth and be capable of meeting the demands of high volume manufacturing. Laser produced plasmas (LPP) have emerged as a promising source for EUV emission, but higher in-band conversion efficiency (CE) and debris control must first be realized.1 Tin is considered the material of choice for producing this plasma, as its plasma emits strongly in the EUV in-band region, contributed by various ionic stages (Sn8+ – Sn14+). However, the net emission of 13.5 nm photons is controlled by plasma opacity, which depends on level populations of different ionic states, ionization balance, and electron density. For obtaining the highest CE, ideal plasma temperatures and densities should be created for the longest possible period of time with the maximum collectable size.2 Reheating of a pre-formed plasma is one of the methods for controlling density and hence optimizing plasma opacity for maximum EUV emission.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129088410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Destabilization of backward waves by space charge in gyrotron beams 回旋加速器光束中空间电荷对后向波的不稳定作用

2011 Abstracts IEEE International Conference on Plasma Science Pub Date : 2011-06-26 DOI: 10.1109/PLASMA.2011.5993069

J. Yu, T. Antonsen, G. Nusinovich, A. Vlasov

{"title":"Destabilization of backward waves by space charge in gyrotron beams","authors":"J. Yu, T. Antonsen, G. Nusinovich, A. Vlasov","doi":"10.1109/PLASMA.2011.5993069","DOIUrl":"https://doi.org/10.1109/PLASMA.2011.5993069","url":null,"abstract":"The beam tunnels of high power gyrotrons can become unstable to the excitation of gyro-backward waves, degrading beam quality and lowering the efficiency of the desired, operating mode. Efforts are usually made to suppress this instability by disrupting or damping the backward propagating electromagnetic mode. We study here the effect on start oscillation currents of the coupling of the backward wave to the forward propagating electrostatic cyclotron maser instability [1, 2]. Normally, in the analysis of the gyro-bwo an absolutely unstable mode is formed due to coupling of the backward propagating structure mode and the forward propagating beam perturbation. When space charge is included the forward propagating signal also acquires gain due to the negative mass effect, and this results in a lowering of the start current threshold for the gyro-bwo instability. The start current is minimal when the cyclotron resonance condition is maintained over the beam tunnel. This may take place when an axial wavenumber of unstable perturbations on the beam corresponds to the tapering of the magnetic field. This implies the modes will be sensitive to the magnetic field tapering and to the spread in electron axial velocity.","PeriodicalId":221247,"journal":{"name":"2011 Abstracts IEEE International Conference on Plasma Science","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128647208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1