Application of Dark Field X-Ray Microscopy in Epitaxial Thin Film

While the atomic structure is fundamental to the understanding of the static and dynamic properties of functional materials, it was realized that some phenomena emerge because of the collective behavior of a large number of atoms. One of such collection of atoms is domains in the material, whose formation, interaction, and evolution under external stimuli would dictate success or failure of the material. Studying domains would require tools with good spatial-resolution as well as large enough sampling area/volume. A diffraction based, dark field X-ray microscopy method, the X-ray reflection interface microscopy (XRIM), can be very useful in studying domains at the surfaces, buried interfaces, and inside of thin film material systems, with sub-nanometer sensitivity in the surface normal direction and better than 100 nm lateral resolution.<br/><br/>With the penetrating power of hard X-rays, XRIM can emphasize the features at different depth from the top surface by selecting proper scattering conditions, making it an excellent candidate to study the films in-operando in real time. Combined with the reciprocal space mapping (RSM), the spatially resolved structure evolution can be identified. A couple examples will be discussed to demonstrate the capability of XRIM method and its potential applications in a broader field.