Development of quantitative characterization method of microstructures by X-ray scattering

使用传统实验室x射线源从Si（001）光栅表面进行的高分辨率x射线衍射显示每个布拉格反射周围的分辨率有限的光栅干涉峰。结果发现，卫星峰的位置和强度为我们提供了周期和宽度等结构信息，以及纳米尺度下光栅侧壁的粗糙度。光栅制作在Si（001）表面，宽度为0.8 mm，高度为10mm，周期为4.5 mm，长度为6.5mm。光栅的数量是47。x射线衍射测量在探测器前用Ge（220）通道切割单色仪（CuKalpha_1）和Ge（220）通道切割分析仪进行。利用衍射仪的自动程序在113和111布拉格点附近观测卫星峰。对于113布拉格点，选择了高入射角和低入射角两种衍射几何形状。在高角度几何结构中没有观测到卫星峰，而在低角度几何结构中观测到-0.8mum分离的干涉峰。光栅的实际宽度可以从峰的位置估计出来。峰的强度衰减为我们提供了光栅侧壁粗糙度的信息。此外，在111布拉格点附近的峰上观察到光栅周期内的细条纹。

High-resolution X-ray diffraction from a Si (001) grating surface using a conventional laboratory X-ray source reveals resolution-limited grating interference peaks around each Bragg reflection. As the results it was found that the positions and the intensities of the satellite peaks provide us with structural information such as the period and the width, as well as the roughness of the side walls of the gratings in a nanometer scale.The gratings were made on a Si (001) surface, of which width, height, period, and length were 0.8mum, 10mum, 4.5mum, and 6.5mm, respectively. The number of the gratings is 47. The X-ray diffraction measurements were performed with a Ge (220) channel-cut monochrometor (CuKalpha_1) and a Ge (220) channel-cut analyzer in front of the detector. The satellite peaks were observed around the 113 and 111 Bragg points by using the automatic program for the diffractometer. Two diffraction geometries, high- and low-angle incidence geometries, were selected for the 113 Bragg point. In the high-angle geometry the satellite peaks were not observed, while the interference peaks of the -0.8mum separation were measured in the low-angle geometry. The actual width of the gratings can be estimated from the positions of the peaks. The intensity decay of the peaks give us the information for the roughness of the side walls of the gratings. Furthermore, the fine fringes for the period of the gratings were observed on the peaks around the 111 Bragg point.