Schifferle Andreas, Dommann Alex, Neels Antonia
Helbling Technik AG, Aarau, Switzerland.
Empa, Swiss Federal Laboratories for Materials Science and Technology, Center for X-ray Analytics, Dübendorf, Switzerland.
Sci Technol Adv Mater. 2017 Mar 31;18(1):219-230. doi: 10.1080/14686996.2017.1282800. eCollection 2017.
New methods are needed in microsystems technology for evaluating microelectromechanical systems (MEMS) because of their reduced size. The assessment and characterization of mechanical and structural relations of MEMS are essential to assure the long-term functioning of devices, and have a significant impact on design and fabrication. Within this study a concept for the investigation of mechanically loaded MEMS materials on an atomic level is introduced, combining high-resolution X-ray diffraction (HRXRD) measurements with finite element analysis (FEA) and mechanical testing. HRXRD measurements were performed on tensile loaded single crystal silicon (SCSi) specimens by means of profile scans and reciprocal space mapping (RSM) on symmetrical (004) and (440) reflections. A comprehensive evaluation of the rather complex XRD patterns and features was enabled by the correlation of measured with simulated, 'theoretical' patterns. Latter were calculated by a specifically developed, simple and fast approach on the basis of continuum mechanical relations. Qualitative and quantitative analysis confirmed the admissibility and accuracy of the presented method. In this context [001] Poisson's ratio was determined providing an error of less than 1.5% with respect to analytical prediction. Consequently, the introduced procedure contributes to further going investigations of weak scattering being related to strain and defects in crystalline structures and therefore supports investigations on materials and devices failure mechanisms.
由于微机电系统（MEMS）尺寸减小，微系统技术中需要新的方法来评估它们。对MEMS的机械和结构关系进行评估和表征对于确保设备的长期运行至关重要，并且对设计和制造有重大影响。在本研究中，引入了一种在原子水平上研究机械加载的MEMS材料的概念，将高分辨率X射线衍射（HRXRD）测量与有限元分析（FEA）和机械测试相结合。通过对对称（004）和（440）反射进行轮廓扫描和倒易空间映射（RSM），对拉伸加载的单晶硅（SCSi）试样进行了HRXRD测量。通过将测量的图案与模拟的“理论”图案相关联，对相当复杂的XRD图案和特征进行了全面评估。后者是基于连续介质力学关系通过专门开发的简单快速方法计算得出的。定性和定量分析证实了所提出方法的可接受性和准确性。在此背景下，确定了[001]泊松比，相对于分析预测，误差小于1.5%。因此，所引入的程序有助于进一步研究与晶体结构中的应变和缺陷相关的弱散射，从而支持对材料和器件失效机制的研究。
