Data for: "Imaging Threading Dislocations and Surface Steps in Nitride Thin Films Using Electron Backscatter Diffraction"

This dataset provides the experimental data used to generate the figures in the paper entitled "Imaging Threading Dislocations and Surface Steps in Nitride Thin Films Using Electron Backscatter Diffraction". Electron backscatter diffraction (EBSD) measurements were performed using a Nordlys EBSD detector from Oxford Instruments attached to an FEI Quanta 250 variable pressure field emission SEM. The EBSD data was acquired at 20 kV and 30 kV and at a sample tilt of 70° with respect to the normal of the incident electron beam. Abstract of the paper: Extended defects, like threading dislocations, are detrimental to the performance of optoelectronic devices. In the scanning electron microscope, dislocations are traditionally imaged using diodes to monitor changes in backscattered electron intensity as the electron beam is scanned over the sample, with the sample positioned so the electron beam is at, or close to the Bragg angle for a crystal plane/planes. Here we use a pixelated detector instead of single diodes, specifically an electron backscatter diffraction (EBSD) detector. We present post-processing techniques to extract images of dislocations and surface steps, for a nitride thin film, from measurements of backscattered electron intensities and intensity distributions in unprocessed EBSD patterns. In virtual diode (VD) imaging, the backscattered electron intensity is monitored for a selected segment of the unprocessed EBSD patterns. In center of mass (COM) imaging, the position of the center of the backscattered electron intensity distribution is monitored. Additionally, both methods can be combined (VDCOM). Using both VD and VDCOM, images of only threading dislocations, or dislocations and surface steps can be produced, with VDCOM images exhibiting better signal-to-noise. The applicability of VDCOM imaging is demonstrated across a range of nitride semiconductor thin films, with varying surface step and dislocation densities.

本数据集为题为《利用电子背散射衍射成像氮化物薄膜中的穿晶位错与表面台阶》的论文中所有图表提供了实验数据。
电子背散射衍射（Electron Backscatter Diffraction，EBSD）测试采用牛津仪器（Oxford Instruments）的Nordlys EBSD探测器，搭载于FEI Quanta 250变压场发射扫描电子显微镜（SEM）完成。
EBSD数据的采集参数为：加速电压20 kV与30 kV，样品相对于入射电子束法线的倾角为70°。
本论文摘要如下：穿晶位错这类扩展缺陷会对光电器件的性能造成不利影响。传统扫描电子显微镜的位错成像方法，是利用二极管监测电子束扫过样品时背散射电子强度的变化，此时需将样品定位至电子束与某一或多个晶面满足布拉格角或接近布拉格角的位置。本研究采用像素化探测器替代单个二极管，具体为电子背散射衍射（EBSD）探测器。我们提出了一种后处理技术，可从未经处理的EBSD图案的背散射电子强度与强度分布数据中，提取氮化物薄膜的位错与表面台阶图像。在虚拟二极管（Virtual Diode，VD）成像中，会对未经处理的EBSD图案的选定区域监测背散射电子强度。在质心（Center of Mass，COM）成像中，则监测背散射电子强度分布的中心位置。此外，两种方法可结合使用（VDCOM）。通过VD与VDCOM两种方式，可分别生成仅含穿晶位错，或同时包含位错与表面台阶的图像，其中VDCOM成像的信噪比更优。本研究验证了VDCOM成像在一系列表面台阶与位错密度各异的氮化物半导体薄膜中的适用性。