原子团离子在AlxGa1—xAs基体组分SIMS定量分析中的应用

通过检测原子团离子ＭＣｓ＾＋和ＭＡｓ＾－（Ｍ是基体元素）对ＡｌｘＧａ１－ｘＡｓ基体组分进行了定量的分析，考虑了ＭＩＱ＝１５６ＳＩＭＳ上所测迷些原子团离子的能量分主其对分析结果的影响，并对正、负ＳＩＭＳ，测量方法做出比较。     

H+辐照前后C-SiC涂层的红外吸收光谱研究

对在不锈钢基体上用离子束混合技术沉积的C－SiC涂层，进行了二次离子质谱（SIMS）及傅氏变换红外吸收光谱（FI－IR）的分析。研究了不锈钢基体涂覆前后的H^ 辐照的氢浓度分布以及H^ 辐照前后涂层的红外光谱振动吸收峰的变化，对SiC涂层阻氢的机理进行了探讨。     

注入氮离子的SiC涂层阻氢性能研究

利用离子束混合－离子注入（Ar^ ）和磁控溅射相结合的实验技术在HR－1不锈钢基体上制备了注入N^ 的SiC涂层，并用表面分析手段对所制备涂层的表面形貌，剖面形貌、相结构，表面成分，表面元素的化学态进行了分析，结果表明：制备的涂层结构致密，表面平整、膜层成分均匀；涂层与基体之间形成了一明显的过渡层，增强了涂层和基体之间的结合力，用二次离子质谱（SIMS）对充氘涂层的阻氢性能进行了定性分析，结果表明，涂层元素与氢形成稳定的化学键，抑制了氢的扩散和迁移，使得涂层具有一定的阻氢能力。     

MCs~ -SIMS技术及其应用

强烈的基体效应一直是造成二次离子质谱（SIMS）难以定量分析和解释的主要原因。受其影响，常规SIMS，即M±－SIMS（检测原子型二次离子M＋或M－，M是要分析的元素）的适用范围受到了很大的限制。近几年来，上述状况已经通过一种新技术开发得到明显改善，这就是MCS＋－SIMS技术，即在CS＋一次离子轰击下检测分子型二次离子MCS＋而不是M±。由于该技术能明显减小甚至消除基体效应，从而开辟了SIMS定量分析的新途径。在综述MCS＋－SIMS技术的由来、发展、特点和应用以及MCS＋的生成机理的基础上，介绍了该技术的扩展思路。     

1998年国际二次离子质谱学研讨会暨第二届全国二次离子质谱学学术会议在京举行

1998年国际二次离子质谱学研讨会［1998InternationalSymposiumonSecondaryIonMassSpectrometry（IS－SIMS’98）］暨第二届全国二次离子质谱学学术会议［SecondaryChinessNationalConferenceonSecondaryIonMassSpectrometry（SIMSⅡ，China）］于1998年4月6－10日在北京清华大学举行。这是首次在我国召开的国际SIMS会议，同时是1993年我国成功地召开了第一届全国SIMS会议（SIMS　Ⅰ，China）后，首次与香港和台湾合作召开的中国SIMS会议。会议由北京清华大学与香港科技大学、台湾新竹清华大学和中国二次离子质谱学会议组…     

二次离子质谱仪离子枪溅射速率的能量依赖关系

本文绘出了MIQ－56型SIMS仪器中离子枪溅射速率和一次束能量及扫描档次的数学表达式，并且通过实验测量加以证实；同时还得到了一次束直径和束流强度的线性关系，为SIMS实验参数选择提供了有力依据。     

二次离子发射的LTE模型及其在GaAs样品中的应用

介绍了二次离子发射的局部热平衡（LTE）模型的发展过程及其在GaAs样品SIMS定量分析中的应用，并尝试了用GaAs基体元素作内标的定量分析方法，取得了较好的结果。     

飞行时间二次离子质谱--强有力的表面、界面和薄膜分析手段

二次离子质谱（Secondary ion mass spectrometry，简称SIMS）是一种对表面灵敏的质谱技术，建立在表面各种类型带正、负电荷原子或分子发射的基础上。用飞行时间（Time of flight，简称TOF）仪器对这些二次离子进行质量分析，能确保并行质量登录、高质量范围、高流通率下的高分辨和精确质量测定这些优异性能。配合细聚焦扫描一次离子束，可在优于1nm的高深度分辨和优于50nm的横向分辨本领下，实现对表面优于单层ppm(百万分之一）量级的极高检测灵敏度。当今TOF－SIMS已发展为一种成熟且完善的表面分析技术。极高的灵敏度，再加上即使对大分子及不易挥发性分子都独具的敏感性，使它成为很多高技术领域不可缺少的分析手段，这些领域包括微电子学、化学和材料科学以至纳米技术和生命科学等。本文简述了TOF－SIMS的原理、仪器及其多方面的应用和展望。     

清洁砷化镓表面二次离子质谱及其与一次氩离子能量关系的研究

本文针对砷化镓材料中微量元素的定量分析进行了二次离子质谱的应用基础研究。对离子束清洗及超高真空下清洁砷化镓表面SIMS谱的获得进行了研究,讨论了谱的特征,研究了主要谱峰强度与一次氩离子能量的关系,还对可能出现的GaOH_x~ (X=0,1,…)原子团离子进行了实验研究和讨论,最后对国产GaAs材料的一些实验结果进行了简要的对比。     

分子束外延生长GaAs中δ掺杂研究

利用二次离子质谱（SIMS）和电化学剖面C－V方法研究了生长温度对GaAs中理想Siδ掺杂结构的偏离和掺杂原子电激活效率的影响。实验发现，外延生长Siδ掺杂GaAs时，随着生长温度的升高，Si掺杂分布SIMS峰非对称展宽，表面分凝作用加强，但不影响Si原子的扩散。另外，Si施主电激活效率随着生长温度的提高而增大。     

GaAs中Si的二次离子质谱定量分析

评述砷化镓中硅SIMS定量分析的进展，讨论了相对灵敏度因子法。对此种GaAs的原始参考物质，用实验确认了其可靠性。为常规定量分析研制了二次参考物质。对一些关键实验因素，如样品装载、仪器参数以及离子选择等进行了仔细研究，并评价它们对定量重复性、精确性、检测限和基体效应的影响。Cs 源入射时GaAs中Si定量分析精度在15％内；检测AsSi二次离子时，29Si的检测限达5×1014atoms／cm3。     

AlN陶瓷衬底的SIMS和XRD测量

AlN陶瓷中成分与杂质对于AlN的性能具有决定性作用。用二次离子质谱（SIMS）和X射线衍射（XRD）对清华大学材料系电子封装用的AlN陶瓷进行了研究。SIMS谱表明AlN衬底中除Al,N以外还有C，O，Si，Ca，Y等元素，其中有些是表面污染。衬底的SIMS深度分析表明样品O，Ca，Y信号都很强，且分布均匀，说明样品中含有Y2O3，CaO添加剂。AlN样品的XRD谱与AlN的JCPDS卡片对照，在测量范围内卡片上所有峰均出现，且晶面间距符合很好。在XRD谱上找到了与Y2O3和CaO对应的衍射峰。     

残气质谱分析在LAS—2000上的应用

详尽地探讨高真空及超高真空中的残余气体的质谱分析方法。运用这些方法在ＬＡＳ－２０００二次离子质谱仪上进行了应用研究。精确地分析了ＬＡＳ－２０００的本底真空，发现其超高真空中含有较多的碳氢化合物，这些碳氢化学物主要影响氢（氘）轰击石墨的化学腐蚀研究的结果分析。     

Oxygen isotopic measurements by secondary ion mass spectrometry in uranium oxide microparticles: a nuclear forensic diagnostic

To exploit oxygen isotopic measurement by SIMS as a diagnostic tool in nuclear forensics, the magnitude and reproducibility of 0-isotope instrumental mass discrimination for O-isotope standards in the SIMS laboratory at the Institute for Transuranium Elements has been evaluated. Tests for matrix-dependent discrimination effects on three different O-isotope standards with substantially different matrix compositions have been performed. The results were checked by an interlaboratory comparison of O-isotope discrimination with those obtained in the SIMS laboratory at the Lawrence Livermore National Laboratory on two standards. The results from the two laboratories are in very good agreement, indicating statistically indistinguishable instrumental mass discrimination factors for 180/160 ratios on the Cameca 6f and 3f, when the analyses are performed under the experimental conditions described. The 2sigma(mean) uncertainties of these factors are in the range of 0.3-0.9%. In accordance with the tested methodology, 0-isotope compositions were measured in three particulate uranium oxide samples of nuclear forensics interest.     

High-reactivity matrices increase the sensitivity of matrix enhanced secondary ion mass spectrometry

Secondary ion mass spectrometry (SIMS) is a desorption/ionization method in which ions are generated by the impact of a primary ion beam on a sample. Classic matrix assisted laser desorption and ionization (MALDI) matrices can be used to increase secondary ion yields and decrease fragmentation in a SIMS experiment, which is referred to as matrix enhanced SIMS (ME-SIMS). Contrary to MALDI, the choice of matrices for ME-SIMS is not constrained by their photon absorption characteristics. This implies that matrix compounds that exhibit an insufficient photon absorption coefficient have the potential of working well with ME-SIMS. Here, we evaluate a set of novel derivatives of the classical MALDI matrices α-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB) for usability in ME-SIMS. This evaluation was carried out using peptide mixtures of different complexity and demonstrates significant improvements in signal intensity for several compounds with insufficient UV absorption at the standard MALDI laser wavelengths. Our study confirms that the gas-phase proton affinity of a matrix compound is a key physicochemical characteristic that determines its performance in a ME-SIMS experiment. As a result, these novel matrices improve the performance of matrix enhanced secondary ion mass spectrometry experiments on complex peptide mixtures.     

Identification of cellular sections with imaging mass spectrometry following freeze fracture

Freeze-fracture techniques have been used to maintain chemical heterogeneity of frozen-hydrated mammalian cells for static TOF-SIMS imaging. The effects the fracture plane has on scanning electron microscopy and dynamic SIMS images of cells have been studied, but the implications this preparation method has on static SIMS have not been addressed to date. Interestingly, the chemical specificity and surface sensitivity of TOF-SIMS have allowed the identification of unique sections of rat pheochromocytoma cells exposed to the sample surface during freeze fracture. Using the extensive chemical information of the fractured surface, cellular sections have been determined using TOF-SIMS images of water, sodium, potassium, hydrocarbons, phosphocholine, and DiI, a fluorescent dye that remains in the outer leaflet of the cell membrane. Higher amounts of potassium have been imaged inside a cell versus the surrounding matrix in a cross-fractured cell. In other fractures exposing the cell membrane, phosphocholine and DiI have been imaged on the outer leaflet of the cell membrane, while phosphocholine alone has been imaged on the inner leaflet. In this paper, we discuss how imaging mass spectrometry isused to uniquely distinguish three possible sections of cells obtained during freeze fracture. The identification of these sections is important in choosing cells with a region of interest, like the cell membrane, exposed to the surface for a more thorough investigation with imaging static TOF-SIMS.     

Reduction of matrix effects in polystyrene/poly(methylene methacrylate) blends by metal-assisted secondary ion mass spectrometry

Secondary ion mass spectrometry (SIMS) is a very surface sensitive analysis technique with low detection limits. The main drawback of SIMS is its inherent incapability of providing quantitative information about sample compositions due to the frequent occurrence of ionization- and sputter-induced matrix effects. Metal-assisted SIMS (MetA-SIMS) is an experimental approach that consists in covering an organic sample with a minute amount of a noble metal prior to a static SIMS analysis, the main objective being an increase of the characteristic secondary ion intensities. We show in this article that MetA-SIMS is also a simple and efficient tool for reducing matrix effects in a set of polymer blend samples containing different relative concentrations polystyrene (PS) and poly(methylene methacrylate) (PMMA). These findings can be explained by diffusion processes leading to a sample surface configuration consisting of individual polymer chains embedded in a common Ag matrix.     

半导体材料二次离子质谱定量分析中的基体效应

通过对Wilson等人由实验得出的Si，Ge，GaAs，GaP，InP，CdHgTe半导体和SiO2，Si3N4等绝缘基体中70多种注入元素相对灵敏度因子（RSF）值的综合分析，定义logFRS－Ii直线斜率为基体效应因子。发现基体效应因子值随基体平均原子序数的增加而增大，随基体平均电负性值的增大而减小，随基体氧化物生成热的增加而减小。应用本文提出的二次正离子发射理论分析式较好地解释了这些实验现象，并对影响基体效应的其他因素进行了进一步的讨论。     

表面膜对含硼HA177-2黄铜腐蚀的影响

测定了成膜前后加硼HA177－2铝黄铜的静态腐蚀速率、脱锌系数和电化学行为.用离子探针（SIMS）分析了铝黄铜表面膜的组成和深度分布．结果表明：表面膜中富集Zn、AI、B；退火形成的表面膜提高了铝黄铜在中性介质中的耐蚀性，但不能提高它在酸性介质中的耐蚀性能．     

Lithium isotope composition of basalt glass reference material

We present data on the lithium isotope compositions of glass reference materials from the United States Geological Survey (USGS) and the National Institute of Standards and Technology (NIST) determined by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS), thermal ionization mass spectrometry (TIMS), and secondary ionization mass spectrometry (SIMS). Our data on the USGS basaltic glass standards agree within 2 per thousand, independent of the sample matrix or Li concentration. For SIMS analysis, we propose use of the USGS glasses GSD-1G (delta(7)Li 31.14 +/- 0.8 per thousand, 2sigma) and BCR-2G (delta(7)Li 4.08 +/- 1.0 per thousand, 2sigma) as suitable standards that cover a wide range of Li isotope compositions. Lithium isotope measurements on the silica-rich NIST 600 glass series by MC-ICPMS and TIMS agree within 0.8 per thousand, but SIMS analyses show systematic isotopic differences. Our results suggest that SIMS Li isotope analyses have a significant matrix bias in high-silica materials. Our data are intended to serve as a reference for both microanalytical and bulk analytical techniques and to improve comparisons between Li isotope data produced by different methodologies.