硫对注入YSZ单晶的金属铂在退火过程中结晶的影响

用卢瑟福背散射－沟道技术（ＲＢＳ－Ｃ）和Ｘ射线衍射技术（ＸＲＤ）研究了Ｐｔ和Ｓ注入ＹＳＺ（Ｙ２Ｏ３稳定的ＺｒＯ２）后产生的损伤和退火过程中损伤的恢复及注入Ｐｔ的晶化。ＲＢＳ－Ｃ分析表明ＹＳＺ在室温下注入存在较强自退火效应;ＸＲＤ分析结果示出硫对铂的晶化产生很大影响。     

带有AlN插入层的GaN薄膜的结构及应变研究

利用金属有机化学汽相沉积（MOCVD）法在硅衬底上生长具有AlN插入层的GaN外延膜,采用高分辨X射线衍射（HRXRD）和卢瑟福背散射/沟道（RBS/Channeling）技术研究分析其结构和应变性质。从RBS<0001>沟道谱可知,该外延膜具有良好的结晶品质,χ_min=2.5%。利用不同方位角上XRD摇摆曲线测量,可得出GaN（0001）面与Si（111）面之间的夹角β=1.379°。通过对GaN（0002）和GaN（1015）衍射面的θ-2θ扫描,可以得出GaN外延膜在垂直方向和水平方向的平均弹性应变分别为-0.10%±0.02%和0.69%±0.09%。通过对{1010}面内非对称<1213>轴RBS角扫描可得出由弹性应变引起的四方畸变e_T在近表面处为0.35%±0.02%。外延膜弹性性质表明GaN膜在水平方向具有张应力(e∥>0)、在垂直方向具有压应力(e^⊥<0),印证了XRD的结果。四方畸变是深度敏感的,通过对不同深度的四方畸变计算可知,AlN插入层下面的GaN外延膜弹性应变释放速度比AlN层上面的GaN层弹性应变释放快,说明AlN层的插入缓解了应变释放速度。     

关于X射线在晶体中衍射的理论研究

对X射线衍射强度公式进行了修正,使其理论计算的结果得到了明显的改善。对简单立方晶体银和铁的衍射相对强度进行计算,并与标准PDF卡片相比较发现:对银和铁而言,未修正公式计算的结果:Ag的偏差范围为84%～165%,Fe的偏差范围为66%～90%。修正后的公式计算的结果则与实验数据符合得比较好,Ag的偏差范围为24%～42%,Fe的误差范围为2%～5%。     

一个PIXE-RBS离子束分析系统的刻度

四川大学原子核科学技术研究所依托2.5 MeV范德格拉夫静电加速器搭建了质子诱发X射线荧光分析(Proton Induced X-ray Emission,PIXE)与卢瑟福背散射分析(Rutherford Backscattering Spectrometry,RBS)相结合的离子束分析系统,描述了该分析系统和刻度过程。通过10个金属单质的PIXE-RBS测量,刻度得到的仪器常数H值是一条随能量变化的曲线,然后采用最小二乘法拟合确定了X射线探测器前的Mylar膜有效厚度、选择性滤膜的有效厚度和中心小孔大小,从而得到H值。为了对刻度H值进行检验,在相同实验条件下测量了标准粘土样品元素成分,测量数据与证书数据符合得较好。刻度结果将用于以后的PIXE-RBS分析。     

石墨晶体预衍射X射线荧光分析中的基体影响

X射线荧光分析是一种重要的仪器分析方法，在元素分析方面有着非常广泛的应用。但在后处理工艺分析中，X射线荧光分析应用较少，主要原因是样品本身的放射性对测量产生较大干扰。本实验室根据文献报道以及X射线衍射基本原理，白行设计组装完成了一套石墨晶体预衍射EDXRF分析装置。在实际的测量中，由于基体组成复杂，因此，本工作研究了在1AW中的主要基体元素对U测定的影响。     

聚乙烯膜对样品残余应力测试的影响

采用X2001应力分析仪测试了α-Fe和铍样品表面分别覆盖聚乙烯膜前后的残余应力,探讨了残余应力测试值变化的原因及其规律。样品表面覆盖聚乙烯膜后,由于校准距离D的增大,使得衍射峰向低角度方向偏移,从而引起应力实测值发生了改变。通过对应力实测值进行修正,可获得样品内的真实应力。     

铈掺杂对二氧化钛纳米颗粒微结构的影响

报道了铈掺杂对二氧化钛纳米颗粒微结构的影响。用溶胶一凝胶方法制备了不同铈含量的TiO2纳米颗粒,在不同的温度下煅烧得到纳米样品系列。用X射线衍射(XRD)、小角X射线散射(SAXS)以及X射线吸收谱(XAFS)技术研究了铈离子掺杂和煅烧温度对二氧化钛纳米颗粒微结构的影响。结果发现：铈离子的掺入有效地抑制了二氧化钛纳米颗粒的生长和在高温下的相变。纳米颗粒“自相似”的分形结构与铈含量和煅烧温度有关。用核心-壳层模型描述了钛的近邻原子结构。     

杂质对X射线在炸药中衰减规律影响的研究

对某炸药（纯炸药和含金属片的炸药）进行了X射线检测,并对穿透率进行拟合,通过对拟合结果分析得出了在管电压和管电流一定的条件下X射线在某炸药中随药柱的增加其衰减规律符合三次拟合。同时得到杂质的密度越大,衰减越明显,不同厚度的同一杂质,厚度大的衰减明显。     

大气环境中溶剂添加剂对制备钙钛矿薄膜的影响

钙钛矿太阳能电池中有机-无机杂化钙钛矿薄膜的品质很大程度上决定了其器件效率。作为简单有效的制备方法,近几年一步溶液旋涂法不断改进工艺,迅速广泛应用于高质量钙钛矿薄膜的制备,其中在前驱体溶液中添加二甲基亚砜（Dimethyl sulfoxide,DMSO）以及旋涂过程中滴加反溶剂被普遍认为是行之有效的手段,可以大幅提升钙钛矿的结晶质量,获得均匀致密的薄膜。本文通过控制钙钛矿薄膜制备过程中前驱体溶液DMSO和旋涂过程中反溶剂乙醚的添加与否,在大气环境制备了4种不同的薄膜样品,结合扫描电子显微镜、同步辐射掠入射X射线衍射以及器件效率测试等研究了薄膜的表面形貌、结晶性与基于它们制备的器件性能的差异,探究了DMSO和乙醚两种添加剂对钙钛矿成膜的影响、机制及其构效关系。同时,进一步采用同步辐射掠入射X射线衍射研究4种薄膜样品在空气环境下原位加热过程中钙钛矿结晶、退化以及期间晶格结构的演变,发现前驱体溶液中加入DMSO对于钙钛矿结构形成具有延迟作用,而反溶剂乙醚的滴加则对薄膜形貌、结晶、晶面取向乃至器件光电转换效率具有显著的提升,并且其钙钛矿结构具有较好热稳定性。本文的发现将为改善钙钛矿薄膜制备工艺以进一步提升其器件光电转换效率与稳定性提供一定的实验依据。     

强流电子束在角向磁场中产生的硬X射线测量

利用X射线吸收片以及和剂量片相结合的方法,测量了强流电子束在角向磁场中产生的硬X射线的剂量和能谱分布;采用仅对光子能量124keV以下的X射线相应灵敏的PIN半导体探测器,测量了硬X射线时间谱;研究了硬X射线的产生与靶厚、磁场电流的关系。     

Sputtering and surface state evolution of Bi under oblique incidence of 120 keV Ar ions

The sputtering and surface state evolution of Bi/Si targets under oblique incidence of 120 keV Ar⁺ ions have been investigated over the range of incidence angles 0° ? θ_i ? 60°. Increasing erosion of irradiated samples (whose surface thickness reduced by ∼3% at normal incidence up to ∼8% at θ = 60°) and their surface smoothing with reducing grain sizing were pointed out using Rutherford backscattering (RBS), atomic force (AFM) and X-ray diffraction (XRD) techniques. Measured sputtering yield data versus θ_i with fixed ion fluence to ∼1.5 × 10¹⁵ cm⁻² are well described by Yamamura et al. semi-empirical formula and Monte Carlo (MC) simulation using the SRIM-2008 computer code. The observed increase in sputter yield versus incidence angle is closely correlated to Bi surface topography and crystalline structure changes under ion irradiation.     

The property of Si/SiGe/Si heterostructure during thermal budget characterized by HRXRD

Si/SiGe/Si heterostructures grown by ultra-high-vacuum chemical vapor deposition (UHVCVD) were characterized by Rutherford backscattering/Channeling (RBS/C) together with high resolution X ray diffraction (HRXRD). High quality SiGe base layer was obtained. The Si/SiGe/Si heterostructures were subject to conventional furnace annealing and rapid thermal annealing with temperature between 750℃ and 910℃. Both strain and its relaxation degree in SiGe layer are calculated by HRXRD combined with elastic theory, which are never reported in other literatures. The rapid thermal annealing at elevated temperature between 880℃ and 910℃ for very short time had almost no influence on the strain in Si0.84Ge0.16 epilayer. However, high temperature (900℃@) furnace annealing for 1h prompted the strain in Si0.84Ge0.16 layer to relax.     

Sputtering and crystalline structure modification of bismuth thin films deposited onto silicon substrates under the impact of 20-160 keV Ar ions

The sputtering of bismuth thin films induced by 20-160 keV Ar⁺ ions has been studied using Rutherford backscattering spectrometry, scanning electron microscopy and X-ray energy dispersive and diffraction spectroscopy. These techniques revealed increasing modifications of the Bi film surfaces with increasing both ion beam energy and fluence up to their complete deterioration under irradiation conditions E = 160 keV and φ = 1.5 × 10¹⁶ cm⁻², leaving isolated islands of preferred (0 1 2) orientation on the Si substrate. The observed surface morphology and crystalline structure evolutions are likely due to a complex interplay of interaction mechanisms involving both elastic nuclear collisions and inelastic electronic ones. The measured Bi sputtering yields versus Ar⁺ ion fluence for a fixed ion energy exhibit a significant depression at very low φ-values followed by a steady state regime above ∼2.0 × 10¹⁴ cm⁻². Measured sputtering yields versus Ar⁺ ion energy with fixing ion fluence to 1.2 × 10¹⁶ cm⁻² in the upper part of the yield saturation regime are also reported. Their comparison to theoretical model and SRIM 2008 Monte Carlo simulation predictions is discussed.     

Beam dispersion of ions penetrating through an amorphous compound binary layer

Based on Monte Carlo simulations, we calculated the beam dispersion of ions penetrating through an amorphous binary compound layer with the atomic number of compositional elements ranging from Z = 5 to Z = 80. The scattering probabilities were compared with that obtained by approximating the compound layer as a monatomic target with mean atomic number and mean atomic mass. Very good agreement is observed between the two approaches for the compound substrate having close atomic numbers. An appreciable difference is observed for the substrate having considerably different atomic numbers. However, such differences disappear when the transition from single scattering (corresponding to an ultra thin layer) to multiple scattering (corresponding to a relatively thick layer) occurs. The study reveals the factor determining the validity and limits of the approximation method in studying scattering phenomena, with the motivation to provide a method to easily estimate the dechanneling of an ion beam passing through a crystalline compound target having a surface amorphous layer.     

关于Cu-Au合金溅射机制的研究

本文报道了用热中子活化法测量Cu-Au合金在80keV Ar~+离子不同剂量轰击下的部分溅射产额比S_Cu/S_Au,并用卢瑟福背散射(RBS)技术分析样品中元素的反冲以及表面层成分的相对变化,从而研究了元素择优溅射对表面层变化所起的作用。     

Study of doping uniformity of a 200 kV ion implanter by RBS and sheet resistance measurements

The ion implantation uniformity is of vital importance for an ion implanter.In this paper,we report the,uniformity measurement for a large current ion implanter(LC-16 type) by implanting of 190-keV Ar ions into Si to 3×1016 atoms/cm2,followed by Rutherford backscattering spectroscopy(RBS) and sheet resistance measurement providing quantitative information on spatial distribution of dopants.The implant doses obtained from RBS at selected points of the sample give a spatial uniformity of 5%,which are confirmed by the sheet resistance measurement.While sheet resistance is an indirect method for dose evaluation of ion-implanted samples,RBS provides a competent technique for calibration of the ion implantation system.And both measurements show that good uniformity can be achieved for the ion implanter by tuning of the scanning process.     

Coincident Rutherford Backscattering Spectrometry: A novel technique for measuring charge state distributions in violent ion-atom collisions

Charge-state distributions in violent ion-atom collisions were investigated using a novel combination of traditional Rutherford backscattering spectrometry (RBS), time-of-flight (TOF) coincidence, and position-imaging techniques. The combination is termed Coincident Rutherford Backscattering Spectrometry (CRBS). A special apparatus was built in which the backscattered and recoil ions are time and charge state correlated. CRBS measurements for 0.5 and 0.6 MeV He⁺-Ar collisions are presented. From the recoil ion-projectile ion coincidence measurements of the charge state distributions, it was observed that backscattered projectile ions of the same charge state correlate with different recoil ion charge states and vice versa, indicating that any particular charge state may result from different reaction channels. Moreover, the Ar recoil-ion and He projectile-ion correlation exhibits a strong dependence on the projectile beam energy. An energy deposition model was attempted to account for some of the recoil ion charge state distributions. The model qualitatively accounts for the distributions and confirms that energy loss of a backscattered projectile due to its interaction with the target electrons is very small compared to that due to its interaction with the target nucleus.     

Fitting of RBS data including roughness: Application to Co/Re multilayers

In this work automated fitting of Rutherford backscattering (RBS) data including the effect of roughness is performed, by calculating the effect of roughness on the apparent energy resolution as a function of depth. This depends on the exact type of roughness, and three different models have been implemented: inhomogeneous layer thickness, corrugated sample, and rough substrate surface. Full automated fitting can be performed including one, or more, of the models, with the roughness parameters (e.g. standard deviation of the thickness of any number of layers), as well as the sample structure, as fitting parameters. The code is applied to the system substrate/Re 50 Å/(Co 20 Å/Re 5 Å)₁₆, which had been studied before by other methods. The results are excellent, providing a new tool for RBS data analysis.