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1.
田民波  崔福斋 《物理》1987,16(3):0-0
荷能粒子轰击固体表面,打出离子和中性原子的现象称为溅射.由于离子易于在电磁场中加速或偏转,所以荷能粒子一般为离子,称这种溅射为离子溅射.随着真空技术、薄膜技术、表面分析技术以及表面科学的发展。离子溅射的用途越来越广泛,其重要性也日益为人们所共知.如今,离子溅射在溅射离子源、二次离子质谱分析(SIMS)、离子束分析、溅射镀膜、离子镀、离子和离子束刻蚀、表面微细加工等领域有广泛的应用.同时,溅射?...  相似文献   

2.
田民波  崔福斋 《物理》1987,16(4):0-0
三、合金和化合物的溅射[2,21-23]1.择优(preferential)溅射现象对合金、化合物的溅射与前面所述的对单质的溅射具有十分显著的差别.首先,即使同种原子。由单原子固体变为多种原子固体后,溅射产额也将发生十分显著的变化,这种现象在结合状态发生了很大变化的氧化物等中可以明显地看到.再者.构成固体的每种元素,溅射产额都不相同。所以被溅射固体的表面成分和溅射之前相比,发生了变化,这就是?...  相似文献   

3.
ECR离子源金属离子的产生   总被引:1,自引:0,他引:1  
讨论了ECR离子源金属供料方法,在145GHzECR离子源上应用炉子加热和MIVOC法获得了40Ca11+140eμA和56Fe10+65eμA,并对实验过程和结果作了分析.  相似文献   

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5.
新型相干结构光场由于其在许多领域具有独特的优势,受到越来越多学者的关注.本文回顾了新型相干结构光场构建基础理论,从均匀和非均匀相干结构分类出发,以几种典型的新型相干结构光场为例,重点介绍了其光束模型构建和新奇传输特性,总结归纳了 目前主流的包括泽尼克定理法和模式分解法在内的新型相干结构光场实验产生方法,并讨论了不同方法...  相似文献   

6.
阿秒脉冲光源诞生于21世纪初,是同时具有阿秒时间和纳米空间分辨率的全相干光源,在近20年的时间里,推动了阿秒科学研究不断取得显著的进展和突破.阿秒脉冲为物理、化学、生物、材料、信息等领域的发展提供了全新研究手段和重要创新机遇.本文介绍了阿秒脉冲的重要发展历程,主要综述并总结了高次谐波、阿秒脉冲产生以及阿秒脉冲测量的关键...  相似文献   

7.
本文对Pb_(97.4)Sn_(2.6)合金表面在溅射时所产生的一些现象进行了研究。实验在室温下,利用PHI-590型扫描俄歇微探针进行。根据理论计算结果对实验数据进行分析后,观察到了溅射增强扩散效应。当Ar~ 离子能量为5千电子伏,离子流密度为70微安/厘米~2时,测得锡在合金中的扩散系数为10~(-15)厘米~2/秒量级,影响层厚度约为200埃。  相似文献   

8.
简单介绍了采用炉子加热、 挥发性金属化合物和溅射产生ECR离子源的金属离子的3种方法和实验结果, 主要研究了铜、 锌、 镍和铁等多种电荷态离子的产生. 对3种方法分别进行了探讨.To satisfy the requirements of HIRFL (Heavy Ion Research Facility in Lanzhou), series of experiments have been done to produce metallic ion beams. By now, numerous methods have been tested, in which MIVOC (Metallic Ion from Volatile Compounds), heating oven methods and plasma sputter methods are all included. According to the experiments, the results of using MIVOC methods and heating oven methods are very good. In most of our researches, emphasis was put upon the ion production of iron, Nickel, Tantanum, copper of different charge states. Among the ion beams we have obtained, 210 μA Fe11+, 175 μA Fe12+, 142 μA Fe13+, 25 μA Fe16+, 64 μA Ni10+, 57 μA Ni13+, 31 μA Ni15+ and 15 μA Ni16+ are representative results.  相似文献   

9.
高电荷态金属离子的产生实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
 为满足兰州重离子加速器的实验要求,在14.5GHz高电荷态ECR离子源上做了一系列产生金属离子的实验,尝试了多种方法,包括炉子加热及MIVOC(Metallic Ion form Volatile Compounds)两种方法,其中,用炉子做的结果较理想。实验主要研究了铜、锌、镍多种电荷态离子的产生,具有代表性的是39euA的13+,30euA的Zn13+和29euA的Ni10+。分别给出了这三种金属离子产生的多电荷态束流峰谱图,以及实验的一些其它现象及结果,并对其进行了讨论与总结。  相似文献   

10.
为满足兰州重离子加速器的实验要求,在14.5GHz高电荷态ECR离子源上做了一系列产生金属离子的实验,尝试了多种方法,包括炉子加热及MIVOC(Metallic Ion form Volatile Compounds)两种方法,其中,用炉子做的结果较理想。实验主要研究了铜、锌、镍多种电荷态离子的产生,具有代表性的是39euA的13+,30euA的Zn13+和29euA的Ni10+。分别给出了这三种金属离子产生的多电荷态束流峰谱图,以及实验的一些其它现象及结果,并对其进行了讨论与总结。  相似文献   

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12.
The Coupled Cyclotron Facility (CCF) has been operating at the NSCL since 2001,providing up to 160MeV/u heavy ion beams for nuclear physics experiments.Recent steps,particularly the improvement of the ECR-to-K500 injection line,were taken to improve the CCF performance.For that purpose an off-line ECR source,ARTEMIS-B,was built and used to investigate the impact on beam brightness under various source operating conditions,different initial focusing systems and current analysis dipole.Beam dynamics simulations including space-charge and 3D electrostatic field effects were performed and beam diagnostics including emittance scanner were used,leading to a better understanding of the CCF beam injection process. New initial electrostatic focusing elements such as a large-bore quadrupole triplet and a quadrupole double- doublet with compensating octupole were tested,and a new beam tuning procedure was established to improve the beam brightness for the CCF.Following these efforts,a significant increase of primary beam power out of the CCF has been achieved.  相似文献   

13.
Since the last ECR Workshop,NSCL/MSU has been involved in a vigorous ECR ion source R&D program,which resulted in the construction of an off-line test ECR ion source(ARTEMIS-B)for new beam development and ion optics studies.Also the design and partial completion of a 3rd generation,fully superconducting ECR ion source,SuSI has been accomplished.This paper is an overview of the construction projects and the different R&D activities performed with the existing ion sources.These activities include development of metallic ion beam production methods using evaporation with resistive and inductive ovens and sputtering of very refractory metals.Ion optics developments include testing different focusing elements(magnetic solenoid lens,electrostatic quadrupole triplet lens,Einzel lens,electrostatic double doublet quadrupole combined with an octupole lens),and different beam forming and diagnostics devices.The detailed results will be presented at the workshop in separate talks and posters.  相似文献   

14.
Permanent electric dipole moments (EDMs) violate parity and time-reversal symmetry. Within the Standard Model (SM), they require CP violation and are many orders of magnitude below present experimental sensitivity. Many extensions of the SM predict much larger EDMs, which are therefore an excellent probe for the existence of ‘new physics.’ So far only electrically neutral systems were used for sensitive searches of EDMs. Several techniques, based on storing fast particles in a magnetic storage ring, are being developed to probe charged particles for an EDM. With the introduction of these novel experimental methods, high sensitivity for charged systems, in particular light nuclei, is within reach. The author represents the Storage Ring EDM Collaboration.  相似文献   

15.
Projectile fragmentation provides radioactive beams at intermediate velocities (v/c = 0.3-0.5) by physical means of fragment separation. With the development of position-sensitive photon detectors it has become possible to measure the energies and directions of photons emitted in-flight from such fast-moving exotic beams. This allows the reconstruction of the photons' energies emitted from an exotic projectile with high accuracy. It can be advantageous to employ photon detection in experiments with exotic beams since photons can traverse matter easily and their attenuation can be calculated. Experiments with standard luminosities can be carried out at intermediate beam energies with thick secondary targets (order of g/cm2) and very low incident beam rates (order of particle/s or less). Experimental success in this field is strongly correlated with the development of photon detectors such as position-sensitive scintillation detectors or segmented germanium detectors. In-beam gamma-ray spectroscopy of fast exotic beams has been successfully used at all projectile fragmentation facilities in intermediate-energy heavy-ion inelastic scattering experiments, knockout reactions and fragmentation reactions. Here, we focus on experimental results for neutron-rich exotic nuclei in the π(sd )-shell. Measurements and detector developments carried out at the NSCL at Michigan State University during the last four years are discussed. Received: 1 May 2001 / Accepted: 4 December 2001  相似文献   

16.
17.
The 6.4 GHz ECR ion source that was indigenously developed a few years ago has been operating continuously for injecting oxygen and neon beams to the cyclotron since 1997. VEC-ECR is a single stage high magnetic field ion source provided with a negatively biased electron repeller placed on the axis, near the injection mirror point. The supply of cold electrons and use of low mass mixing gas improve the stability of ECR plasma. Very recently, the effect of aluminum oxide coating on the copper plasma chamber wall has been studied. The plasma chamber wall was coated with aluminum by vacuum evaporation method and then exposed to oxygen gas to form aluminum oxide. It was noticed that the process substantially shifts the charge state distribution to the higher charge state with an enhancement of ion current by an order of magnitude. With the aluminized plasma chamber, the VEC-ECR can now produce 12 μA of O7+, 6.5 μA of Ar12+, 1.5 μA of Kr20+ and 1.0 μA of Xe31+.  相似文献   

18.
At the NSCL a reaccelerator with design end energy of 3 MeV/u for 238U, called ReA3, is approaching the end of construction. ReA3 will be coupled to a gas stopper at the NSCL fragmentation facility to provide rare-isotope beams of nuclides not available at ISOL facilities in this energy range. An Electron Beam Ion Trap (EBIT) will be used to provide highly charged ions at an energy of about 12 keV/u. The charge breeder is followed by a room-temperature radiofrequency quadrupole (RFQ) and a series of superconducting linear accelerator structures. Initial commissioning results from the EBIT and its charge-over-mass separator are presented.  相似文献   

19.
20.
In the beginning of the 90s,T.Taylor and his collaborators demonstrated ECR sources operating at low frequency(i.e.2.45GHz)are able to produce very intense single charge light ion beams. At CEA/Saclay,the SILHI source developments started in 1995.Since 1997 more than 100mA proton or deuteron beams are routinely produced in pulsed or continuous mode.To comply with ADS reliability constraint,important improvements have been performed to increase the installation reliability.Moreover,to optimize the beam transport in the low energy beam line,the extraction system was carefully designed and space charge compensation studies were undertaken.An important step has been reached in 2005 with the development of a permanent magnet source able to produce a total beam of 109mA at 85kV. A new test bench named BETSI,especially dedicated to permanent magnet source developments,is presently under construction.It will allow analysing positive or negative extracted beams up to 50keV and 100mA. In addition,for several years work has been done to optimize the production of negative hydrogen ion beam with such an ECR source.Recent analysis pushed towards the construction of a new set up based on a multicusp magnetic configuration. After a brief overview of the CEA/Saclay source developments,this article will point out on the recent results and present status.  相似文献   

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