离子束增强沉积法制备Mo2N和Mo2-xTixN薄膜及其结构与性能研究

分别采用氮离子束增强沉积和Ｎ－Ｔｉ离子束同步增强沉积工艺制备了Ｍｏ２Ｎ和Ｍｏ２－ｘＴｉｘＮ薄膜,用ＸＲＤ,ＴＥＭ、划痕和阳极极化方法研究了两者的结构与性能。     

低能氮离子束注入固态5‘—dTMP的辐照损伤研究

对３０ｋｅＶ氮离子束辐照５－ｄＴＭＰ核苷酸引起的无机磷和碱基的释放进行了多方面的研究，得到机磷产率和碱基产生量的剂量效应曲线，以及０．１ｍｏｌ／ＬＮａＯＨ碱处理对它们的影响。碱处理不仅增加了无机磷的释放量，而且还使辐照产生的游离碱基受到损伤而裂解。碱处理后立测量得知，受辐照样品的碱溶液中无机磷的含量为其水溶液中的１．７倍，而样品碱溶液中的碱基浓度却只有其水溶液中的０．５倍左右。碱处理４０ｍｉｎ后。     

辛酸─1—~(13)C的合成与分析

将以溴代正庚烷为原料合成的格氏试剂溴化正庚基镁与Ｂａ１３ＣＯ３和浓Ｈ２ＳＯ４作用产生的１３ＣＯ２进行羧化反应,通过水解,提纯,制得辛酸─１─１３Ｃ,产率可达９０％─９３％。用薄层层析对其进行了定性分析,利用ＭＳ、ＩＲ、１Ｈ－ＮＭＲ和１３Ｃ－ＮＭＲ对其进行了结构分析和测定１３Ｃ丰度（８９．５％）,并按口服药物的质量要求,用ＩＣＰ－ＡＥＳ和ＡＦＳ方法对有关金属元素进行了定量测定。     

中国科学院物理研究所的离子束分析及离子注入改性研究

介绍了中国科学院物理研究所离子束研究室的主要设备、分析方法、离子注入材料改性研究以及近年来在半导体材料、高Ｔｃ超导材料、环保等领域中的研究工作。     

离子束—中性束技术及离子束应用技术的发展动向

离子束－中性束技术和离子束应用技术是离子束技术中的两个重要方面，其发展方向取决于科学研究和应用技术开发的需要，本文简述了它们的现状和发展动向。     

N—甲基—^14C苄基胺及其亚硝胺的合成

报道了Ｎ－甲基－＾１４Ｃ苄基和Ｎ－甲基－＾１４Ｃ苄基亚硝胺的合成，比活度约为９．２×１０＾１１Ｂｑ／ｍｏｌ。由高压液相色谱仪测得的化学纯度和放化纯度均大于９５％。     

辛酸-1-13C的合成与分析

将以溴代正庚烷为原料合成的格氏试剂溴化正庚基镁与Ｂａ＾１３ＣＯ３和浓Ｈ２ＳＯ４作用产生的＾１３ＣＯ２进行羧化反应,通过水解,提纯,制得辛酸－１－＾１３Ｃ,产率可达９０％－９３％,用薄层层析对其进行了定性分析,利用ＭＳ、ＩＲ、＾１Ｈ－ＮＭＲ和＾１３Ｃ－ＮＭＲ对其进行了结构分析和测定＾１３Ｃ丰度（８９．５％）,并按口服药物的质量要求,用ＩＣＰ－ＡＥＳ和ＡＦＳ方法对有关金属元素进行了定量测定。     

碳团簇及C60负离子的产生

利有铯负离子溅射源和石墨阴极产生并引出了碳团簇负离子流，观察到了一些电子亲和势很小的团簇，用Ｃ６０／Ｃ７０混合物做阴极，也引出了Ｃ６０及其碎片的负离子束，分析了碳团簇负离子束流的质谱组成特点和束流变化的一些规律。     

离子束辅助沉积制备TiN/Si3N4纳米超硬膜的工艺研究

采用离子束辅助沉积法(Ion beam assisted deposition,IBAD)在单晶硅片上进行沉积制备了TiN/Si3N4纳米复合超硬薄膜;研究了辅助束流、轰击能量和Ti:Si靶面积比等工艺参数对TiN/Si3N4超硬纳米复合薄膜性能的影响.此外采用纳米硬度计、光电子能谱(X-ray photoelectron spectrum,XPS)和x射线衍射分析(X-raydiffraction,XRD)方法研究了纳米复合薄膜的性能、成分与组织结构;采用原子力显微镜(Atomic forcemicroscopy,AFM)分析了薄膜的表面形貌,并初步探讨了TiN/Si3N4纳米复合超硬薄膜的生长机理.     

团簇沉积C-N薄膜的研究

利用荷能团族沉积装置在高阻硅（111）衬底上沉积了碳氮薄膜。通过红外光谱、拉曼谱和X光电子能谱对薄膜的结构和化学组分进行了分析。结果表明,薄膜中存在N－sp^3(β－C3N4的键合方式）,但以N－^2C和C＝C双键的结合方式为主。     

Ion beam processing of single crystalline silicon carbide

A short review is presented concerning problems of ion beam processing of single crystalline silicon carbide. Emphasis is given to recent results on point defects, extended defects, amorphisation and recrystallisation, electrical activation of dopant atoms, and metallisation.     

Ion beam synthesis and doping of photonic nanostructures

Optically-active silica nanowires are produced by metal-induced growth on silicon substrates using ion-implantation, with two different strategies employed for their fabrication. The first is based on Er implantation of nanowires produced by a thin-film Pd catalyst layer, and the second employing implanted Er as both the catalyst and dopant. The luminescence properties of the resulting Er-doped silica nanowires are reported and compared with similarly implanted fused silica samples. Comparison shows that the luminescence lifetime of Er is increased by incorporation within the nanowires due to a reduction in the density of available optical states in these structures. Additional details of the synthesis, structure and properties of these functionalised nanowires are also presented.     

Ion beam synthesis and recrystallization of amorphous SiGe/SiC structures

Si_1−xGe_x amorphous layers implanted with different doses of carbon (between 5 × 10¹⁵ and 2 × 10¹⁷ cm⁻² and annealed at 700°C and 900°C have been analyzed by Raman and Infrared spectroscopies, electron microscopy and Auger electron spectroscopy. The obtained data show the synthesis of amorphous SiC by implanting at the highest doses. In these cases, recrystallization only occurs at the highest annealing temperature (900°C). The structure of the synthesized SiC strongly depends on the implantation dose, in addition to the anneal temperature. For the highest dose (2 × 10¹⁷ cm⁻²), crystalline β-SiC is formed. Finally, a strong migration of Ge towards the Si substrate is observed from the region where SiC precipitation occurs.     

Ion beam analysis and microscopic characterization of natural topaz stones

Rutherford backscattering spectroscopy (RBS) and elastic recoil detection (ERD) techniques were used to determine the presence of metallic as well as nonmetallic (also hydrogen) components in two kinds of natural topaz stones originating from Sri Lanka and Nigeria. A computer simulation program was applied in order to compare the theoretical and experimental results of the RBS analysis. The changes in surface morphology induced by irradiation with high energy analysing ion beams were monitored using optical microscopy. RBS analysis proved the presence of trace amount of metallic admixtures in the stones — potassium, zinc, nickel or cobalt, lead (and/or bismuth) were detected mainly in the surface region of the samples. ERD analysis allowed to determine the total content and depth distribution of hydrogen; the depth distribution of hydrogen was proved to be almost uniform. Microscopic investigation indicated the existance of damage and precipitates on the polished surfaces, whereas radiation damage, probably connected with helium-blistering, was observed after the ERD analysis.     

Ion beam analysis of materials in the PBMR reactor

South Africa is developing a new type of high temperature nuclear reactor, the so-called pebble bed modular reactor (PBMR). The planned reactor outlet temperature of this gas-cooled reactor is approximately 900 °C. This high temperature places some severe restrictions on materials, which can be used. The name of the reactor is derived from the form of the fuel elements, which are in the form of pebbles, each with a diameter of 60 mm. Each pebble is composed of several thousands of coated fuel particles. The coated particle consists of a nucleus of UO₂ surrounded by several layers of different carbons and SiC. The diameter of the fuel particles is 0.92 mm. A brief review will be given of the advantages of this nuclear reactor, of the materials in the fuel elements and their analysis using ion beam techniques.     

Ion beam analysis of rare earth nitride thin films

We report compositional measurements on highly disordered GdN, DyN, ErN and SmN thin films, grown using ion-assisted deposition and capped with GaN AlN and Al, grown using the same technique. Ion beam analysis technique of RBS, PIXE and nuclear reaction analysis (NRA) were used to determine the composition of the capped films ex situ, and show that GaN and AlN protects the GdN, DyN and SmN films from oxidation over a timescale of at least a few days. NRA depth profiles indicate that oxygen is incorporated into the films during deposition and is located at the GaN/GdN interface. The ion beam analysis measurements showed that stoichiometric ratios can be obtained and oxygen impurities are significantly reduced by varying the film deposition parameters. The successful protection of the rare earth (RE) nitride films from oxidation allows for a reliable analysis of the RE films in the as-deposited state.