非平衡磁控溅射系统离子束流磁镜效应模型

为了研究非平衡磁控溅射沉积系统的等离子体特性，采用常规磁控溅射靶和同轴约束磁场构成非平衡磁控溅射沉积系统.在放电空间不同的轴向位置，Ar放电，02Pa和150V偏压条件下，采用圆形平面离子收集电极，测量不同约束磁场条件下的饱和离子束流密度.研究结果表明，在同轴磁场作用下，收集电极的离子束流密度能达到饱和值9mA/cm2左右，有利于在沉积薄膜的过程中产生离子轰击效应.根据磁流体理论分析了同轴约束磁场形成的磁镜效应和对放电过程的影响机理.实验与模型计算结果的比较表明，模型从理论上表达了同轴磁场约束对非平衡磁控溅射等离子体特性的影响规律. 关键词： 等离子体 金属薄膜/非磁性 磁控溅射 磁镜     

强流二极管阳极靶温度和热形变模拟

以电子束在靶中的能量沉积剖面为桥梁,建立了二极管阳极靶温度和热形变模拟方法。该方法可获知二极管不同工作状态下靶的温度分布和热形变情况,为靶热-力学损伤研究提供基础数据,为二极管构型设计和寿命提升提供技术支撑。将该方法应用于“强光一号”短γ二极管,计算结果显示:当阳极离子密度大于1014 cm?3时（强箍缩）,靶表面温度最高可达5500～6000 ℃,热形变量达约4.5 mm;无离子流时（弱箍缩）,温度处在4500 ℃左右,形变为2.8～3.5 mm。     

Characterization of the ion cathode fall region in relation to the growth rate in plasma sputter deposition

In plasma-assisted magnetron sputtering, the ion cathode fall region is the part of the plasma where the DC electric field and ion current evolve from zero to their maximum values at the cathode. These quantities are straightforwardly related to the deposition rate of the sputtered material. In this work we derive simple relations for the measurable axially averaged values of the ion density and the ion current at the ion cathode fall region and relate them with the deposition rate. These relations have been tested experimentally in the case of an argon plasma in a magnetron sputtering system devoted to depositing amorphous silicon. Using a movable Langmuir probe, the profiles of the plasma potential and ion density were measured along an axis perpendicularly to the cathode and in front of the so-called race-track. The deposition rate of silicon, under different conditions of pressure and input power, has been found to compare well with those determined with the relations derived.     

Generation of a submillisecond electron beam with a high-density current in a plasma-emitter diode under the conditions of open plasma boundary emission

The generation of a 250-μs-wide electron beam in a plasma-emitter diode is studied experimentally. A plasma was produced by a pulsed arc discharge in hydrogen. The electron beam is extracted from a circular emission hole 3.8 mm in diameter under open plasma boundary conditions. The beam accelerated in the diode gap enters into a drift space in the absence of an external magnetic field through a hole 4.1 mm in diameter made in the anode. The influence of electron current deposition at the edge of the anode hole on the beam’s maximum attainable current, above which the diode gap breaks down, is studied for different accelerating voltages and diode gaps. The role of processes occurring on the surface of the electrodes is shown. For an accelerating voltage of 32 kV, a mean emission current density of 130 A/cm² is achieved. The respective mean strength of the electric field in the acceleration gap is 140 kV/cm. Using the POISSON-2 software package, the numerical simulation of the diode performance is carried out and the shape of steady plasma emission boundaries in the cathode and anode holes is calculated. The influence of the density of the ion current from the anode plasma surface on the maximum attainable current of the electron beam is demonstrated.     

Deposition of amorphous hydrogenated semiconductors by magnetron assisted silane decomposition

Magnetron assisted silane decomposition (MASD) is proposed as a method for deposition of a-Si:H and its alloys. In this method a silane containing gas mixture is passed through the magnetron plasma near a target and decomposed there. The deposition rate in the case of the c-Si target is increased 3 times compared to magnetron sputtering and film properties are changed. a-SiSn:H is obtained with a Sn target.     

阴阳极等离子体运动对强箍缩离子束二极管束流特性的影响

 主要研究了阴阳极等离子体运动对“闪光二号”加速器强箍缩离子束二极管束流特性的影响。给出了考虑阴阳极产生的等离子体运动对二极管间隙影响的Child-langmuir流、弱聚焦流、强聚焦流和饱和顺位流4个阶段的离子流和二极管总束流修正公式，利用这些修正公式计算的二极管总束流和离子束流强度与实测结果符合很好，在此基础上分析了提高离子束流强度和效率的方法，通过调整加速器参数，实验得到了峰值能量约500 keV，峰值电流约160 kA的高功率离子束。     

强流二极管阳极电子束时域能量沉积特性模拟

以强流脉冲电子束为研究对象,提出了一种基于离散时间、限定靶面位置,通过测量靶面不同时刻入射角分布,利用蒙卡程序计算得到电子束的能量(r, z)二维分布沉积值的方法。给出了典型弱箍缩平板二极管(电压峰值700 kV、阻抗7 Ω)阳极靶面不同位置时域的能量沉积值,分析了(0, 0°),(25 mm, 135°),(36 mm, 270°)三个位置纵切剖面的能量沉积特性,结果表明：在各个时间段内电子束入射能量确定的情况下,能量沉积特性与入射角呈现相关性,仿真结果与实验结果符合较好,偏差均小于10%;距阳极靶心25 mm以外的靶面位置,受束流箍缩影响,入射角分布变化较大;当入射角较小时(小于40°),强流电子束能量沉积峰值深度约0.2 mm;当入射角超过40°时,能量沉积峰值深度减小到0.1 mm左右;而阳极靶心位置附近,受束流箍缩影响较小,这些位置的能量沉积特性更接近于小角度入射角情形。     

Pulse intense metal-ion diode with a vacuum arc plasma anode

An intense pulsed ion beam of metal was extracted from a magnetically insulated ion diode operated in a mode of plasma prefill generated from a vacuum arc discharge, anode plasma source. With this ion diode, an intense metal-ion beam of a high melting-point metal (Ta) was obtained. A variety of operational modes appeared, depending on the amount of plasma in the diode gap at the initiation of the high-voltage pulse. The energy, current, and duration time of the ion beam were 20~100 keV, ~1 kA, and 1 μs, respectively. Measurements of ions were performed with an ion energy analyzer or a biased ion collector located at the end of a long drift tube and a Thomson parabola ion spectrometer. The Ta ions in the first to fifth states of ionization were detected accompanied by C⁺, O⁺, F⁺, and H⁺ . A Ta ion beam current of about half the total ion flux was obtained in this experiment     

Development of protective metal coatings on aluminum by magnetron sputtering

Depositions of copper and titanium coatings on aluminum foils and polished aluminum plates for thier protection against corrosion in alkaline media were performed. The coatings were deposited in three different types of magnetron sputtering systems: a direct current (DC) magnetron discharge, a high current impulse magnetron discharge, and a DC magnetron discharge with melted cathode. Only aluminum foils coated with copper films obtained by combined ion-plasma technology, which included preliminarily sputtering of the aluminum surface with an ion beam, deposition of a dense interlayer in the DC magnetron discharge with ion assistance of initial stage of deposition, and deposition of additional layer in the magnetron discharge with melted cathode, were resistant against 30 wt % NaOH solution.     

Computer Simulation of High-Power Ion Beam Generation Using the Plasma Erosion Opening Switch and Microsecond Store Systems

This paper deals with computer simulation of plasma erosion opening switch (PEOS) operation in the context of short-pulse high-power ion beam (HPIB) generation in microsecond store systems. The scaling of PEOS parameters and ion diode characteristics with various operating conditions was determined. The simulations showed the best PEOS characteristics for a hydrogen plasma (i.e., the lowest mass) with a high flow velocity and low density, although for some applications a plasma with A/Z > 1 may be preferable. It was shown that the efficiency of HPIB generation in the diode depends on its location relative to the PEOS, the time delay of anode plasma formation, the use of a spiral electrode in the PEOS region, and the use of an arrangement involving an ion return current bypass through the PEOS region. The optimization of the PEOS and ion diode with coaxial configurations and 100 kJ stored in the 600-kV Marx yielded a 16-percent overall efficiency HPIB generation in the diode, with a diode voltage and power of 4.2 MV and 0.42 TW, respectively.     

高压耦合高功率脉冲磁控溅射的增强放电效应

等离子体源离子注入与沉积技术作为一种可生产高结合力、高致密度涂层的真空镀膜技术,具有广阔的应用前景,尤其适用于高载荷工况下服役的功能涂层制备.该技术中金属等离子体源是关键,而现有的脉冲阴极弧源结构复杂,且由于伴随"金属液滴"而需要增加过滤装置.本文研究了另一种简单结构的金属等离子体源备选一高功率脉冲磁控溅射源(HPPMS)的放电特性,采用等离子体发射光谱仪探索了不同的耦合高压对HPPMS放电靶电流特性和等离子体特性的作用.发现耦合高压对HPPMS放电有明显的促进作用,相同靶电压下的放电强度大幅增加,相对于金属放电,耦合高压对气体放电的促进作用更加明显,但在自溅射为主的高压放电阶段对金属放电的促进作用明显增强.讨论了耦合高压对HPPMS放电的增强机制,发现耦合高压自辉光放电、耦合高压和HPPMS电压构成双向负压形成的空心阴极效应,以及耦合高压鞘层改善的双极扩散效应都对HPPMS放电的增强有明显作用.     

Relativistic electron beam generation in a plasma-filled diode withfoilless injection into a dense plasma

In the experiments an relativistic electron beam (REB)-plasma interaction, the foilless injection of REB from a magnetized diode is of special interest due to the low spread angle of the beam and high repetition rate of the shots. In the experiments presented, the problem of diode shortening in the presence of a dense plasma from the interaction chamber has been solved using a special drift pipe as an anode of the foilless diode. The electron beam (U_d~0.7 MeV, t _b~100-200 ns) produced by an axially symmetric magnetically insulated diode has been injected into a magnetized hydrogen plasma column with density ranging from 1·10¹⁵-3·10 ¹⁶ cm^-3. It has been found that the anode pipe substantially reduces the plasma flow into the diode gap, but does not stop it completely, thus the REB generation in a plasma-filled diode has taken place. In some regimes of the beam generation it becomes possible to increase significantly the injected current and total energy deposition of the beam in comparison with the case of a vacuum magnetized diode of the same geometry. The experiments have shown effective dense plasma heating under the foilless injection     

预充等离子体密度对杆箍缩二极管特性的影响

在杆箍缩二极管工作前预先填充一定密度的等离子体,可以改善二极管特性,从而提高二极管出射X射线的剂量率。建立了预充等离子体的杆箍缩二极管的粒子模拟模型,通过收集轰击到阳极上的电子,诊断其轴向分布,可以给出不同时刻的束流箍缩特性。利用剑光一号加速器低阻抗状态(1 MV/9 /40 ns)开展了预充等离子体的杆箍缩二极管实验研究。预充适当密度的等离子体后,二极管阻抗降低到10 ,X射线辐射剂量从0.76 mGy提高到3.19 mGy,侧向焦斑从9 mm降到4 mm。模拟结果和实验基本符合。     

Influence of the Basic Process Parameters on the Ion/Atom Arrival Rate Ratio during Magnetron Sputter Deposition of Thin Carbon Films

The behaviour of the ratio of the argon ion flux and the sputtered atom flux to the substrate with the variation of the basic process parameters was studied in a planar magnetron sputtering system. Finding ways to control this ratio is important with respect to carrying out ion-assisted thin film growth by magnetron sputtering under well-defined conditions. Combined deposition rate measurements and plasma probe measurements were carried out in order to determine the ion/atom arrival rate ratio. In addition calculations of the neutral atom flux were performed on the basis of a simple model and the results compared with the measured values. A considerable change in the values of the ion/atom arrival rate ratio with the variation of the argon pressure and the discharge power was found under operating conditions, at which the back diffusion of the sputtered material is pronounced. The distribution of the ion flux over the substrate surface was found to become more homogeneous with the increase of the working pressure or the target-to-substrate distance.     

“闪光二号”加速器HPIB的产生及应用初步结果

主要给出了“闪光二号”加速器高功率离子束(HPIB)产生及应用研究的初步结果.介绍了强箍缩反射离子束二极管的结构及工作原理，给出了考虑阴阳极产生的等离子体运动对二极管间隙影响的饱和顺位流修正公式.实验得到的离子束峰值能量约500keV，峰值电流约160kA.介绍了利用高功率离子束(质子束)轰击¹⁹F靶产生6—7MeV准单能脉冲γ射线的初步实验结果，给出了利用高功率脉冲离子束模拟1keV黑体辐射x射线对材料的热-力学效应初步研究结果. 关键词： 高功率离子束 箍缩二极管 准单能脉冲γ射线 热-力学效应     

Method for modifying the structure and elemental composition of the solid surface during a high-voltage vacuum discharge

A new method for modifying the surface of a solid, which makes it possible to change effectively the structure and elemental composition of the surface with a high precision, is developed and tested experimentally. The method is based on the action of the plasma of a pulsed high-voltage vacuum discharge, the ion beam from the plasma, and the electron beam on a solid target. The emission and plasma parameters are observed in a pulsed electric field produced in the diode system to which a pulsed voltage with an amplitude of ～10³–10⁵ V and a duration from 10^?9 to 10^?5 s is applied.     

筒形溅射阴极的磁场优化及其高功率放电特性研究

基于高功率脉冲磁控溅射(HiPIMS)技术开发的筒形溅射阴极,配合电磁系统可有效地提升等离子体的输运效率.然而电磁系统的引入反作用于筒内放电特性,从而使靶面放电面积和放电强度无法同时维持.鉴于此,本文通过调整磁场布局,研究了靶面切向(横向)磁场和法向(纵向)磁场对靶面放电的作用规律,优化后靶面切向磁场分布更加均匀,磁场强度高于40 mT的靶面区域占比由51%增至67%,同时法向峰值强度外移,强度由73 mT增至96 mT.采用Ar/Cr体系放电发现:相同工艺条件下,优化后的溅射阴极辉光变亮,靶电流增大,放电面积变宽,放电特性得到显著提升.利用等离子体整体模型仿真和发射光谱仪检测发现优化后离子电流和光谱强度得到明显提升,Cr粒子密度提高一倍,增至2.6×10^20 m^–3,且离化率上升至92.1%,同时输出离子通量提高近一倍,实现了靶面放电与离子输出的双促进.     

To the Kinetics of Nitrogen Incorporation during dc Magnetron Deposition

Investigations of nitrogen incorporation during film deposition by dc magnetron sputtering with a CrSiAl target in Ar/N₂ mixtures have been carried out in the range of the metallic mode. The rate of the nitrogen consumption is proportional to the nitrogen partial pressure during deposition and to the amperage. The corresponding rate constant decreases with the argon pressure. Furthermore, the condensation rate of the target species decreases with the nitrogen partial pressure and is determined by the rate constant of the nitrogen consumption. The experimental results are explained by a 4-stepped reaction sequence of nitrogen incorporation consisting in (1) ionization, (2) ion bombardment of the target and formation of a coverage by plating, (3) removal of the coverage by the sputter process, (4) condensation on the substrate.     

沉积工艺对二氧化锆薄膜生长特性影响的研究

利用反应离子束溅射、反应磁控溅射和电子束蒸发在K9基底上沉积ZrO2薄膜，并用原子力显微镜对薄膜表面形貌进行测量。通过数值相关运算，对不同工艺条件下薄膜生长界面进行定量描述，得到了薄膜表面的粗糙度指数、横向相关长度、标准偏差粗糙度等参量。由于沉积条件的不同，薄膜生长具有不同的动力学过程。在反应离子束溅射和反应磁控溅射沉积薄膜过程中，薄膜生长动力学行为均可用Kuramoto-Sivashinsky方程来描述，电子束蒸发制备薄膜的过程可以用Mullins扩散模型来描述，并发现在沉积薄膜过程中基底温度和沉积过程的稳定性对薄膜表面特征影响很大。     

Deposition of transparent indium tin oxide electrodes by magnetron sputtering of a metallic target on a cold substrate

Indium tin oxide layers with a surface resistance of 50 Ω/□ and a transmission in the visible range of up to 100% are obtained by magnetron sputtering of a metallic target on a cold substrate without ion enhancement of deposition and subsequent annealing. It is shown that the above parameters of the layers can be achieved in a wide range of oxygen partial pressures by controlling the deposition rate and in a wide range of deposition rates by controlling the oxygen partial pressure. An unambiguous dependence of the deposition rate on the oxygen partial pressure in the chamber is constructed.