当前位置:主页 > 科技论文 > 化学论文 >

EDS分析的若干影响因素研究

发布时间:2018-10-25 16:12
【摘要】:当前能谱仪(EDS)在显微成分分析中获得广泛应用,但对同一个分析样品,不同的分析者会做出不同的分析结果,元素含量差异较大。选择的扫描电子显微镜(SEM)和能谱仪参数是否合理,样品自身条件处理是否得当均会直接影响到分析结果的准确性;因此提高定量分析结果的准确性很有必要,操作参数的选择、技巧的运用以及样品自身条件的处理是值得探讨的。本文从样品制备、SEM和EDS工作参数的选择和能谱的分析与处理等对EDS定量分析准确度影响因素进行了探讨。本论文使用的设备主要为日本电子JEM-6490型SEM,美国EDAX-Genesis型X射线EDS。具体研究内容如下:(1)峰漂移会影响定量分析结果,因此在进行相关实验之前,需要进行峰位校正,确定峰位拟合完美。进行点分析时,分析模式选用缩小光栅模式。获取峰位后先进行峰自动识别和可视化峰剥离,若有误差再进行手动标定。对于工作参数的选择来说,用低加速电压分析轻元素,高加速电压分析重元素;工作距离的大小改变特征射线的出射角;束斑控制着死时间和计数率的变动,从而影响搜集时间的选择。这四个工作参数对含量精确度均有影响,但影响能力是否显著需要进行验证;该实验借助SPSS软件完成正交设计实验,实验表明这些因素对含量的影响并不显著,但对每一种元素而言,各参数的影响力仍有区别。(2)明确工作参数对定量分析呈非显著性影响后,开始探究样品物理状况对定量分析的影响。样品首先需满足有导电性,这样避免荷电现象的出现;样品各元素含量要均匀性分布,这利用软件进行均匀性检验确定,这可以排除含量分布不均匀带来的影响。样品表面总存在污染,对于局部性污染,可以调整放大倍数控制观察视野,来分别测试污染和基体;若是全区性碳污染,只需调整加速电压,即可分别观察;长时间的抽真空对降低碳含量作用不明显。对于小尺寸的样品,但当样品尺寸明显小于样品台的尺寸,自身高度较小时,成分含量会受到样品台的影响。表面倾斜的样品会使X射线的吸收路程会减小,导致轻元素含量增加。样品表面的凹凸会明显影响X射线的产生和激发,因此可对试样表面进行研磨处理。对于带腔体的样品,当失效区域距离腔体壁的间距不小于腔体壁高度时,不易受到腔体壁的遮挡作用。
[Abstract]:At present, (EDS) is widely used in microanalysis, but for the same analytical sample, different analyzers will make different analytical results, and the content of elements will vary greatly. Whether the parameters of the scanning electron microscope (SEM) and the energy spectrometer are reasonable or not, and whether the sample's own conditions are properly handled will directly affect the accuracy of the analytical results, so it is necessary to improve the accuracy of the quantitative analysis results and the choice of the operating parameters. The application of the technique and the treatment of the sample's own condition are worth discussing. In this paper, the factors influencing the accuracy of EDS quantitative analysis are discussed from the aspects of sample preparation, selection of working parameters of SEM and EDS, and analysis and treatment of energy spectrum. The main equipment used in this thesis is Japanese electronic JEM-6490 SEM, American EDAX-Genesis X-ray EDS.. The specific research contents are as follows: (1) the peak drift will affect the quantitative analysis results, so before the relevant experiments, the peak position correction is needed to determine the perfect fitting of the peak position. For point analysis, the analysis mode is reduced grating mode. After the peak position is obtained, the peak is automatically identified and visualized, and then calibrated manually if there is any error. For the choice of working parameters, the light element is analyzed with low acceleration voltage, the heavy element is analyzed with high acceleration voltage, the output angle of characteristic ray is changed by the size of working distance, and the dead time and counting rate are controlled by beam spot. This affects the choice of collection time. These four working parameters have an effect on the accuracy of the content, but the influence ability needs to be verified, and the orthogonal design experiment with SPSS software shows that the influence of these factors on the content is not significant. However, for each element, the influence of each parameter is still different. (2) after determining the non-significant influence of working parameters on quantitative analysis, we begin to explore the effect of sample physical condition on quantitative analysis. In order to avoid the phenomenon of charge, the content of elements in the sample should be uniformly distributed, which can be determined by software homogeneity test, which can eliminate the influence of uneven distribution of content. There is always contamination on the surface of the sample. For the local pollution, we can adjust the magnification to control the observation field to test the pollution and the matrix separately, if the whole area of carbon pollution, we only need to adjust the acceleration voltage, we can observe separately. The effect of vacuum for a long time on reducing carbon content is not obvious. For small size samples, however, when the sample size is obviously smaller than that of the sample table, and the height of the sample is small, the composition content will be affected by the sample table. The sample with inclined surface reduces the absorption distance of X-ray and increases the content of light elements. The bump and concave of the surface of the sample can obviously affect the generation and excitation of X-ray, so the surface of the sample can be ground. For the sample with cavity, when the distance between the failure region and the cavity wall is not less than the height of the cavity wall, it is not easy to be blocked by the cavity wall.
【学位授予单位】:电子科技大学
【学位级别】:硕士
【学位授予年份】:2017
【分类号】:O657.62

【参考文献】

相关期刊论文 前10条

1 冯善娥;高伟建;;扫描电镜附EDS能谱仪的使用与维护[J];分析测试技术与仪器;2014年02期

2 刘松;;钢中C元素EDS分析准确度的影响因素[J];失效分析与预防;2014年02期

3 章小余;赵志娟;刘芬;;样品高度对XPS测试的影响[J];分析测试技术与仪器;2013年04期

4 田弋纬;陈绍楷;苗壮;常璐;胡涛涛;;影响EDS分析准确性的因素探讨[J];西安文理学院学报(自然科学版);2010年03期

5 叶建海;包生祥;王娇;张德政;;提高能谱无标样定量分析准确度的参数选择[J];分析测试技术与仪器;2010年02期

6 王英姿;侯宪钦;;带能谱分析的扫描电子显微镜在材料分析中的应用[J];制造技术与机床;2007年09期

7 张步升;样品表面倾角对能谱定量分析精度的影响[J];理化检验(物理分册);1997年07期

8 洪建明,赵晓宁;能谱分析中应注意的几个问题[J];电子显微学报;1994年06期

9 张淑芳;冀克俭;李学;张银生;;加速电压和样品表面粗糙度对EDS分析精度的影响[J];电子显微学报;1993年04期

10 王典亮;洪班德;;原子序数及测试参数对块状样品X射线强度比的影响[J];冶金分析与测试(冶金物理测试分册);1984年05期

相关硕士学位论文 前2条

1 李世岚;电子薄膜的电子探针能谱分析技术研究[D];电子科技大学;2008年

2 赵鸿飞;X射线能谱精确定量技术的研究[D];天津大学;2007年



本文编号:2294205

资料下载
论文发表

本文链接:https://www.wllwen.com/kejilunwen/huaxue/2294205.html


Copyright(c)文论论文网All Rights Reserved | 网站地图 |

版权申明:资料由用户dd9c0***提供,本站仅收录摘要或目录,作者需要删除请E-mail邮箱bigeng88@qq.com