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1.
Ion implanted and deposited Si layers have been recrystallized using pulsed Nd:YAG and cw Ar ion laser irradiation and thermally assisted flash annealing. By use of Rutherford backscattering and channeling. TEM. SEM and interference optical microscopy techniques, two distinct regrowth regimes have been established. I. Liquid phase where regrowth occurs from the underlying solid-liquid interface. In this regime the regrowth layer is free of extended defects, dopant profiles are consistent with liquid diffusion and equilibrium solid solubilities can be exceeded. II. Solid phase where regrowth occurs from the amorphous single-crystal interface. No dopant redistribution is observed.  相似文献   

2.
讨论了三间隙强流离子加速管的聚焦特性,计算了各种能量下离子束聚焦情况,并分析了抑制空间电荷效应所需要的电场强度。最后总结了三间隙加速管设计和调试应注意的问题。  相似文献   

3.
 讨论了三间隙强流离子加速管的聚焦特性,计算了各种能量下离子束聚焦情况,并分析了抑制空间电荷效应所需要的电场强度。最后总结了三间隙加速管设计和调试应注意的问题。  相似文献   

4.
Two years of operation of the Series III Implanter have revealed the full potential of this machine.

The arsenic and phosphorus performance of this machine has greatly exceeded the initial 4 mA design criterion and 8 mA beams of these elements are readily obtainable. The boron beam currents are very dependent upon source history, but 1.2 mA is always available and 3 mA can be obtained from a well conditioned source.

The single gap post-acceleration system has proved very successful, a particular advantage over multi-gap tubes being the 100% beam transmission for any post-acceleration voltage and milliampere beams.

The processor system consists of a large capacity (54–3″. 27–4″, 18–5″ or 9–6″ silicon wafers) racetrack carousel which gives a mechanical scan free of geometric errors for wafers up to 61/2″ diameter. The wafers are mounted on plates with a clamping technique designed for use with an automatic loading system. The large implantation area (approximately 4,000 cm2) minimizes the temperature rise during implantation. The large beam area (approximately 25 cm2 at the carousel) minimizes the pulse heating effect as the wafers sweep through the beam.  相似文献   

5.
An experimental 400 Kev heavy ion implanter has been constructed and put into operation in the Department of Physics, the Peking Normal University. The equipment works on a system of acceleration, analysis, scan, and acceleration (or deceleration). It is composed of the radiofrequency heavy ion source, the front accelerating system, the double focusing symmetrical magnet, the deflexion scanning system, the post-accelerating tube, and the target chamber. The deflecting angle of the magnet is 90°. At present, more than twenty different species of ion beam, such as B, P, As, Al, Mg, Zn, Hg, etc. have been extracted. The extracted ions are used in research work on semiconductors, metals, and superconductive materials. The beam current on the target ranges between 10 μA and 200 μA, and the doping uniformity is ±1.4%.  相似文献   

6.
王三胜  郭强 《物理》2016,45(3):172-179
传感器在诸多领域有着广泛的应用,而随着高温超导技术的快速发展,将高温超导材料应用于磁信号测量成为超导材料应用的一个重要领域。文章探讨了高温超导材料在微弱磁场测量方面的主要应用,介绍了三种在微弱磁场测量方面能达到或有希望达到fT量级的传感器。其中包括:基于约瑟夫森结效应的超导量子干涉器(SQUID),基于超导零电阻效应的巨磁电阻(GMR)磁传感器和由文章作者所在的实验室提出的巨磁阻抗(GMI)/超导复合磁传感器。文章重点介绍了GMI/超导复合磁传感器,并对此传感器在结构和应用方面的最新进展进行了说明。  相似文献   

7.
A high current-low energy implant system for the processing of semiconductor devices at medium-high dopant levels is described. Criteria for selection and design of ion beam components such as ion beam optics, vacuum requirements and reliability are discussed. Variations in wafer uniformities for within wafer, wafer-to-wafer and run-to-run are presented.  相似文献   

8.
林良真  肖立业 《物理》2006,35(06):491-496
近年来高温超导材料研究取得很大进展,它在电力领域的应用研究已受到广泛关注,一些示范样机,诸如高温超导输电电缆、变压器、故障电流限制器、电机和储能装置已经研制成功并投入示范性试验.超导技术是21世纪具有战略经济意义的高新技术,文章将介绍高温超导电力应用研究的新进展及其未来发展的思考.  相似文献   

9.
林良真  肖立业 《物理》2006,35(6):491-496
近年来高温超导材料研究取得很大进展,它在电力领域的应用研究已受到广泛关注,一些示范样机,诸如高温超导输电电缆、变压器、故障电流限制器、电机和储能装置已经研制成功并投入示范性试验.超导技术是21世纪具有战略经济意义的高新技术,文章将介绍高温超导电力应用研究的新进展及其未来发展的思考。  相似文献   

10.
高能激光技术进展与面临的挑战   总被引:1,自引:0,他引:1  
苏毅 《物理》2011,40(2)
文章分析和比较了几种高能激光器技术发展现状和面临的挑战,以及各自可能适用的范围.特别对二极管抽运固体激光器和光纤激光器的几种束相干合成方法和光束质量评价方法进行了分析和讨论.二极管抽运固体激光器和光纤激光器近十年来异军突起,被人们看作是继化学激光器后的第二代高能激光器.光纤激光器进展要比二极管抽运固体激光器滞后5到10年.对几十万瓦以上的激光器来说,在相当长的时间内仍然要靠化学激光器.  相似文献   

11.
高次非球面的工艺技术研究   总被引:1,自引:1,他引:0  
袁吕军  陈韬 《应用光学》2011,32(2):335-342
 高次非球面在光学系统应用中意义重大,但是一直以来缺乏一套快速、有效的工艺方法。利用VC6.0编制了一款面型计算软件以辅助加工,并提出了一种新的高次非球面补偿检验方法。针对一块巡天光谱仪中口径Φ244 mm的一面平面另一面为高次非球面的改正镜开展工艺方法的设计与研究,从铣磨成形开始,根据高次非球面的特点提出了几种新型磨削工艺,建立相应的数学模型。由于高次非球面的特殊性,试验了数控铣磨直接成型法,很大程度上降低后继工艺难度,在细磨和抛光阶段采用数控小工具和整工具研磨相结合,能够很好地克服面型不平滑等技术难题。总结出了一套高效率、低成本、高精度的高次非球面工艺方法。  相似文献   

12.
苏毅 《物理》2011,40(02):107-111
文章分析和比较了几种高能激光器技术发展现状和面临的挑战,以及各自可能适用的范围.特别对二极管抽运固体激光器和光纤激光器的几种束相干合成方法和光束质量评价方法进行了分析和讨论.二极管抽运固体激光器和光纤激光器近十年来异军突起,被人们看作是继化学激光器后的第二代高能激光器.光纤激光器进展要比二极管抽运固体激光器滞后5到10年.对几十万瓦以上的激光器来说,在相当长的时间内仍然要靠化学激光器.  相似文献   

13.
魏晓峰  郑万国  张小民 《物理》2018,47(2):73-83
高功率固体激光是激光聚变、高能量密度物理与前沿基础科学研究必需的实验手段。上世纪六七十年代,老一辈科学家王淦昌、王大珩、邓锡铭、于敏等人以敏锐的科学洞察力与超前的战略眼光,开创了中国激光聚变研究的宏伟工程,为中国高功率固体激光技术的长远发展注入了强劲的东风。中国工程物理研究院(简称中物院)作为激光聚变研究的总体单位,联合中国科学院等国内优势单位,在国家强有力的支持下,推动与组织了中国高功率固体激光技术与装置研制的快速发展。中物院激光聚变研究中心作为高功率固体激光技术研发的总体单位之一,敢于担当、勇于创新,团结协作,坚持三十余载,实现了中国高功率固体激光技术研发历程中的两次“突破”,即突破新一代高功率钕玻璃激光技术,相继研制成功了亚洲规模最大、技术先进的神光-Ⅲ原型装置和神光-Ⅲ激光装置;突破百太瓦超短超强激光关键技术,建成了国内首台输出能力高达200 TW的SILEX-Ⅰ超短超强脉冲激光装置。两次“突破”,不但有力地支撑了中国激光聚变与相关基础科学研究的高速发展,同时实现了中国高功率固体激光技术发展由“望尘莫及”到“望其项背”的跨越,奠定了由“望其项背”到与美、法先进国家“三足鼎立”的坚实基础。  相似文献   

14.
A secondary ion mass spectrometer built around a modified high-dose ion implanter is used to study secondary ion emission in metals over a wide range of primary beam energies. The implanter generates ion beams with energies of up to 150 keV and a substrate current to 30 μA. A modified MX7304A monopole mass spectrometer is applied as an analyzer of secondary ions with mass numbers of up to 400 with a resolution of 1 M at a level of 10% of the peak height. The detection limit for iron is 6.5 ppm. The analyzer is equipped with a small-size filter separating secondary ions in energy. The relative emission intensities of the secondary monatomic and cluster ions of copper for different primary ion beam parameters are studied.  相似文献   

15.
We describe a multifrequency quasi-optical electron spin resonance (ESR) spectrometer operating in the 75–225 GHz range and optimized at 222.4 GHz for general use in condensed matter physics and chemistry. The quasi-optical bridge detects the change of millimeter wave polarization at the ESR condition. A controllable reference arm maintains a millimeter wave bias at the detector. The sensitivity of 2 × 1010 spin/(G Hz0.5), measured on a dilute Mn:MgO sample in a non-resonant probe head at 222.4 GHz and 300 K, is comparable to that of commercial high-sensitive X-band spectrometers. The spectrometer is robust, easy to use and may be operated by undergraduate students. Its performance is demonstrated by examples from various fields of condensed matter physics.  相似文献   

16.
A high-power transformer-type pulse generator (HPPG) is described. It was designed to generate voltage pulses up to 6 MV and current pulses to 2.5 MA. Its highest pulse power is 2.5 TW. Its comparatively small dimensions and broad pulse-spectrum range combine with low cost to make it a convenient tool for physical research in smaller laboratories. Deceased. Institute of High-Current Electronics, Siberian Division, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchenbykh Zavedenii, Fizika, No. 12, pp. 67–75, December, 1997.  相似文献   

17.
支撑光网络发展的硅基光电子技术研究   总被引:3,自引:0,他引:3  
余金中 《物理》2003,32(12):810-815
作为大规模集成电路和化合物半导体光电子器件的制造技术共同构成的一门高新技术 ,硅基光电子技术越来越受到重视 .文章着重介绍中国科学院半导体研究所外延生长SiGe/Si量子结构和Si基器件研究的结果 :采用自行设计的UHV/CVD系统 ,成功地生长出Ⅱ型SiGe/Si量子阱和量子点 ,直到 2 5 0K仍能观察到自组织生长Ge/Si(0 0 1 )量子点的发光峰 ;研制成功SiGe/Si谐振腔增强型光电二极管 (RCEPD)、Y分支MZI光调制器和多模干涉 -马赫 -曾德干涉型光开关等Si基光电子器件 ;1 .3μm处RCEPD的量子效率达到 4 .2 % ,- 5V偏压下暗电流密度 1 2 pA/ μm2 ;2× 2热光型光开关的响应时间小于 2 0 μs,两输出端关态串扰为 - 2 2dB ,通态串扰为 - 1 2dB .  相似文献   

18.
Physics of Particles and Nuclei Letters - A cyclotron system based on the updated MCC-30/15 cyclotron has been developed and manufactured at JSC Efremov Institute of Electrophysical Apparatus...  相似文献   

19.
吴玉敬  纪明 《应用光学》2006,27(4):293-297
针对某型号光电吊舱大速率跟踪时的不平稳现象,提出了一种改进的滤波滞后超前补偿网络。运用MATLAB软件建立了系统机械传动装置的数学模型,分析了该滤波网络对系统动态性能的改进效果。相对于常规滤波器,该滤波网络既考虑了中心谐振频率对系统动态性能的影响,又兼顾了其他谐振点对系统性能的影响。实验结果表明:采用该滤波网络能显著提高系统的动态性能,有效抑制抖动幅度,且数字滤波更易于实现。  相似文献   

20.
针对阳极氧化类试验设计的一套多功能阳极氧化装置,结构简单,操作方便,实验过程易于观察,为相关专业研究员及学生提供了一个操作平台。  相似文献   

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