Atmospheric DBD plasma Deposition of ECO‐Friedly Release Liners for Pressure Sensitive Adhesive Tapes

The presented paper reports on the development of eco‐friendly non‐silicone containing release liners on plastic foils for pressure sensitive adhesive tapes. A solvent free process based on aerosol assisted dielectric barrier discharge (DBD) plasma deposition was used to obtain nano‐sized coatings. Various precursors have been investigated ranging from hydrocarbons and fluorinated hydrocarbons to (meth)acrylates and fluorinated (meth)acrylates. Best results were obtained using 2‐ethylhexyl acrylate. To improved the stability of release properties upon ageing, addition of photo initiators and acrylic cross‐linkers have been evaluated. Tape adhesion tests showed stable release values below 25 cN/20 mm for 2‐ethylhexyl acrylate plasma coatings with acrylic cross‐linkers. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Plasma diffusion and transport in a magnetic duct filter

A cathodic arc plasma source equipped with a curved magnetic duct to filter macro-particles was used to study plasma diffusion and transport in the duct. We determine the optimal duct bias, at which the magnetic duct produces the maximum plasma output, for titanium cathodic arc plasma at 50, 100 and 150 A arc current, and we investigate the parametric effects of the arc current and guiding magnetic field on the optimal duct bias. The optimal bias decreases as the guiding magnetic field increases from 0.01 to 0.04T and is almost independent of the guiding magnetic field when the magnetic field strength ranges from 0.04 to 0.06T, the upper limit for our equipment. The optimal duct bias at 0.04T guiding magnetic field decreases with increasing arc current.     

Different configurations of transferred atmospheric pressure plasma jet and their application to polymer treatment

The employment of atmospheric pressure plasma jets (APPJs) in a large sort of applications is limited by the adversities related to the size of the treated area and the difficulty to reach the target. The use of devices that employ long tubes in their structure has contributed significantly to overcome these challenges. In this work, two different plasma systems employing the jet transfer technique are compared. The main difference between the two devices is how the long plastic tube was assembled. The first one uses a copper wire placed inside a long plastic tube. The other device has a metallic mesh installed in a concentric arrangement between two coaxial plastic tubes. As a result, the two APPJ systems exhibit different properties, with the wire assembly being more powerful, also presenting higher values for the electrical current and rotational temperature when compared to the mesh mounting. X-ray photoelectron spectroscopy (XPS) demonstrates that both configurations were capable of inserting O-containing functional groups on the polypropylene (PP) surface. However, the transferred plasma jet with wire assembly was able to add more functional groups on the PP surface. The results from XPS analysis were corroborated with water contact angle measurements (WCA), being that lower WCA values were obtained when the PP surface presented higher amounts of O-containing groups. Furthermore, the results suggest that the APPJ with wire configuration is more appropriate for material treatments, while the transferred jet with mesh arrangement tends to present lower electrical current values, being more suitable for biological applications.     

射频电感耦合夹层等离子体中的模式转换

本文利用微波相位法和光谱诊断法, 研究了ICP放电等离子体在圆台状夹层等离子体中E模和H模相互转换的物理现象. E模和H模的之间转换过程是一个瞬间突变的, 转换点的输入功率随真空室压强的变化而变化. H模向E模转换的阈值功率低于E模向H模转换的值, 等离子体参数随输入功率变化曲线类似于铁磁物质中的磁滞回线. Ar II 408.2 nm谱线的强度的变化规律和电子密度随功率变化的规律基本一致. 通过本实验可以获得一种电子密度范围为3.85×10¹¹ cm^-3 < n_e < 4.68× 10¹¹ cm^-3, 外表面积为0.3 m², 厚度为2 cm稳定工作的等离子体源.     

有源等离子体在开放大气环境下的反应扩散过程研究

利用一维模型用数值模拟的方法,研究了低气压开放环境下大气等离子体在存在等离子体源的情况下的反应扩散过程.得到了考虑化学反应、扩散以及漂移共同作用下的大气等离子体的主要成分随等离子体注入流量的变化规律及一定流量情况下主要带电成分随时空的演化规律. 将数值模拟结果与一个近似解析公式相衔接,估计达到稳态时维持一定电子密度所需要的等离子体流量,可据此进一步估计所需功率. 关键词： 大气等离子体 等离子体源 数值模拟 反应扩散过程     

Interaction between plasma and electromagnetic field in ion source of 10 cm ECR ion thruster

Through diagnosing the plasma density and calculating the intensity of microwave electric field, four 10 cm electron cyclotron resonance (ECR) ion sources with different magnetic field structures are studied to reveal the inside interaction between the plasma, magnetic field and microwave electric field. From the diagnosing result it can be found that the plasma density distribution is controlled by the plasma generation and electron loss volumes associated with the magnetic field and microwave power level. Based on the cold plasma hypothesis and diagnosing result, the microwave electric field intensity distribution in the plasma is calculated. The result shows that the plasma will significantly change the distribution of the microwave electric field intensity to form a bow shape. From the boundary region of the shape to the center, the electric field intensity varies from higher to lower and the diagnosed density inversely changes. If the bow and its inside lower electric field intensity region are close to the screen grid, the performance of ion beam extracting will be better. The study can provide useful information for the creating of 10 cm ECR ion source and understanding its mechanism.     

Influence of ion species ratio on grid-enhanced plasma source ion implantation

Grid-enhanced plasma source ion implantation (GEPSII) is a newly proposed technique to modify the inner-surface properties of a cylindrical bore. In this paper, a two-ion fluid model describing nitrogen molecular ions N_2^+ and atomic ions N^+ is used to investigate the ion sheath dynamics between the grid electrode and the inner surface of a cylindrical bore during the GEPSII process, which is an extension of our previous calculations in which only N_2^+ was considered. Calculations are concentrated on the results of ion dose and impact energy on the target for different ion species ratios in the core plasma. The calculated results show that more atomic ions N^+ in the core plasma can raise the ion impact energy and reduce the ion dose on the target.     

Calculations of polytropic coefficient for the Tonks–Langmuir Electron-ion plasma with non-Maxwellian electron distributions

The dynamics of the Tonks and Langmuir-type bounded plasma requires a closure relation to make the system of equations self-consistent. Fluid equations are obtained from the moments of velocity distribution function. The two most frequently used closure relations are (a) completely neglecting ion temperature, and (b) setting a constant value for the ion polytropic coefficient. It has been shown that, for a Maxwellian source, either of these assumptions leads to erroneous results. Here, the premise of polytropic coefficient being a function of the potential is extended to a nonthermal plasma. Two different cases for the electron velocity distribution function are studied, namely (a) the Kappa distribution, and (b) the Cairns distribution. Number density (n_i) and temperature (T_i) for the ions are numerically calculated, for respective spectral indices. The polytropic coefficient is then calculated as a function of the potential, using the relation γ_i = 1 + (n_i/T_i)(dT_i/dn_i) . It is concluded that better approximations, vetted by kinetic means, to the polytropic coefficient are crucial for appropriate closure of fluid equations. Present work will be useful in fusion devices where non-Maxwellian electrons may exist due to various physical phenomena.     

Mitigation of energetic ion debris from Gd plasma using dual laser pulses and the combined effect with ambient gas

For the next-generation beyond extreme ultraviolet lithography(EUVL) sources, gadolinium(Gd) plasma with emission wavelength at 6.7 nm seems to be the leading candidate. Similar to the Sn target 13.5 nm light source, ion debris mitigation is one of the most important tasks in the laser-produced Gd plasma EUV source development. In this paper,a dual-laser-pulse scheme, which uses a low energy pulse to produce a pre-plasma and a main pulse after a time delay to shoot the pre-plasma, is employed to mitigate the energetic ion generation from the source. Optimal conditions(such as pre-pulse energy and wavelength, and the time delay between the pre-pulse and the main pulse for mitigating the ion energy) are experimentally obtained, and with the optimal conditions, the peak of the ion energy is found to be reduced to1/18 of that of a single laser pulse case. Moreover, the combined effect by applying ambient gas to the dual-pulse scheme for ion debris mitigation is demonstrated, and the result shows that the yield of Gd ions is further reduced to around 1/9 of the value for the case with dual laser pulses.     

水窗波段附近激光等离子体X光辐射产生的途径

讨论了利用激光等离子体产生水窗波段Ｘ光辐射的可能途径。靶材，即原子序数的选取是决定产生这一波段辐射的基本因素，利用激光等离子体的平衡态和非平衡态特性都可在水窗波段产生亮度Ｘ光辐射，提出利用黑体辐射来实现水窗波段Ｘ光显微成像研究的方案。     

ATOMKI-ECRIS由离子源向等离子体装置的改造

In order to extend the capabilities of the ATOMKI-ECRIS it is being transformed into a modified plasma device by changing its three main components with new ones.The cylindrical plasma chamber is replaced by a larger one(ID=10cm,L=40cm).A new NdFeB multi-pole radial trap was designed and purchased.The basic configuration is 6-pole,but 8-or 12-pole arrangements can also be formed later.The Dresent microwave source(2000W,14.5GHz)and two additional low-power,wide frequency TWT amplifiers give many opportunities to form plasmas with different sizes and characters. Actually a new facility with two sharply different operation modes is being established.All the modifications are reversible so the transformation of the ECRIS into this new device or back can be easily done.     

25kW氩壁稳电弧离子体LTE性的光谱学实验研究

本文利用光谱学诊断方法对25kW氩壁稳电弧等离子体的LTE性进行了实验研究.结果发现在实验条件下等离子体至少是PLTE的,压力高于0.05MPa、电流大于50A时,基本上是LTE的,谱线半宽度与等离子状态无关,只取决于电子密度.     

ECR离子源束流发射度的实验研究

利用最新自行研制的电扫描发射度探测系统, 在ECR离子源上进行了一系列关于ECR离子源引出束流发射度的研究. 这套电扫描发射度探测系统安装在中国科学院近代物理研究所(兰州)的LECR3试验平台的束运线上. 试验中, 通过测量相关参数, 研究了磁场、微波、掺气效应及负偏压效应等对引出束流发射度的影响. 利用实验所得的结果与关于ECR等离子体和离子源束流发射度的半经验理论, 分析推导了离子源各可调参数与ECR等离子体的直接关系, 这为分析探索ECR离子源的工作机制提供了一定的参考依据.     

稀薄等离子体中超辐射的发展过程及相干特性

用量子Ｍａｘｗｅｌｌ－ＢｌｏｃｈＣ－数方程讨论了存在均匀消相阻尼的一维稀薄等离子体系统中电场和极化的发展过程及相干特性，给出了线性阶段的解析结果和非线性阶段的数值结果。数值结果显示了电场和极化的发展过程及随机源对它们的影响。最后给出了电场和极化的相干度及自由电子对相干度的影响。当等离子体频率远小于辐射频率时，自由电子的作用可以忽略。     

Penning型负氢离子源诊断

 为了给小型医用回旋加速器提供负氢离子,研制了一台Penning型负氢离子源。采用发射光谱法对该负氢离子源进行了诊断,同时结合离子源功率变化对离子源工作状态进行了分析。实验测量了不同氢气流量、离子源弧流及磁场条件下,该离子源等离子体氢原子巴尔末系中前三条谱线的相对光强和离子源功率变化,分析了不同工作条件对离子源工作状态的影响。结果表明：在可调节范围内,该离子源的工作状态主要受氢气流量的影响,对离子源弧流及磁场的变化不敏感。     

球形夸克-胶子等离子体演化源的π干涉学分析

本文对球形演化的夸克–胶子等离子体膨胀源进行了2π干涉学分析.夸克–胶子等离子体的演化由相对论流体力学和熵密度的物态方程描述,而2πHanbury-Brown-Twiss(HBT)关联函数由量子几率振幅的路径积分公式计算.研究结果表明,由2π干涉学得到的源的空间参量敏感地依赖于π介子发射源的相空间分布,源的膨胀速度导致HBT半径变小,并会改变HBT半径与冻结温度之间的关系.     

柱形夸克-胶子等离子体演化源的π干涉学分析

本文对Bjorken柱形夸克-胶子等离子体演化膨胀源进行了2π Hanbury-Brown-Twiss (HBT)干涉学分析.利用量子几率振幅的路径积分公式计算2π HBT关联函数并得到对膨胀和静态源的HBT半径. 研究发现，在冻结发射情况下的HBT半径要明显大于没有考虑多重散射吸收情况下的结果，源的膨胀速度导致HBT半径变小.对相变温度宽度为零的Bjorken柱形源，膨胀速度的影响要小于对应的球形源的结果.     

人工等离子体云的时间演化

分析了高空中人工等离子体云的时间演化。发现人工等离子体云中电子密度的空间分布存在着指数衰减区和平缓衰减区。等离子体发生器的粒子流密度仅影响指数衰减区,对平缓衰减区没有什么影响。平缓衰减区中的平均电子密度约为中性分子密度的十万分之一。并且可以覆盖较大范围。这些结果对于电磁波与人工等离子体相互作用的研究、导弹和空间飞行器的等离子体隐身研究及人工等离子体发生器的设计有一定的参考价值。     

SECRAL等离子体中EUV光功率的产生

The high power EUV source is one of key issues in the development of EUV lithography which is considered to be the most promising technology among the next generation lithography.However neither DPP nor LPP seems to meet the requirements of the commercial high-volume product.Insufficiency of DPP and LPP motivate the investigation of other means to produce the EUV radiation required in lithography.ECR plasma seems to be one of the alternatives.In order to investigate the feasibility of ECR plasma as a EUV light source,the EUV power emitted by SECRAL was measured.A EUV power of 1.03W in 4~ sr solid angle was obtained when 2000W 18GHz rf power was launched,and the corresponding CE was 0.5%.Considering that SECRAL is designed to produce very high charge state ions,this very preliminary result is inspiring. Room-temperature ECR plasma and Sn plasma are both in the planned schedule.     

螺旋波激发等离子体源的原理和应用

介绍了一种低气压，高密度等离子体源－螺旋波激发等离子体源，讲述了它的结构位形，该离子源在实际中的应用以及目前研究状况。