NiC/Ti中子超镜是一种高性能的中子多层膜光学元件，是提升中子导管、聚焦装置等中子光学系统的中子利用率的关键之一。为了提升NiC/Ti中子超镜的性能，本文面向具有不同厚度NiC膜层的NiC/Ti多层膜，分别采用X射线掠入射反射和X射线衍射的方法表征了NiC/Ti多层膜的膜层厚度、界面粗糙度和膜层晶向结构。研究结果表明: 随着NiC膜层厚度的增长，除了在较小尺度(≤2.5 nm)，NiC-on-Ti界面的粗糙度基本保持不变; 而Ti-on-NiC界面的粗糙度却呈现出较大的变化。具有不同厚度的NiC膜层的NiC/Ti多层膜的界面粗糙度呈现不对称性的变化，主要原因在于NiC膜层的微结构随着膜层厚度的增长而产生了变化。

NiC/Ti neutron supermirror plays a key role in improving the capability of neutron optics. In order to improve the performance of the neutron supermirror, a study in microstructures and interfaces of NiC/Ti multilayers with varied NiC layer thickness was presented. The thickness, interface roughness and crystalline state of NiC/Ti multilayers were represent by Grazing incidence X-ray reflectivity and X-ray diffraction, respectively. The study results indicate that the NiC-on-Ti interface roughness was almost constant except the thin NiC layer, which has the thickness less than 2.5 nm, however the Ti-on-NiC interface roughness has relatively large changes. The NiC layers transferred from amorphous to polycrystal, as the NiC layer thickness increase from 2.5 nm to 5.5 nm, and both two interfaces and the size of Ni (111) crystalline grains almost kept constant as the NiC layer thickness continue to increase. This different variation between Ti-on-NiC and NiC-on-Ti interface roughness can be attributed to the microstructures changes resulting from varying NiC layer thickness.