The early development of synchrotron white-beam X-ray topography analysis for crystal investigations at Pohang light source-II

Given the limitations imposed by the physical properties of silicon semiconductors, various wide-bandgap-based semiconductor materials are being actively developed and utilized. Also, the use of crystalline materials such as diamond has been increasing in recent years. An understanding of crystal quality and the extent of internal defects is becoming increasingly important for the development and application of such crystalline materials. X-ray topography (XRT) nondestructively yields information on crystal surfaces and internal defects. In particular, XRT using synchrotron X-rays quickly provides high-resolution images of defects in single crystals. Here, we confirmed the utility of synchrotron white-beam XRT (SWXRT). We established the technique and used it to evaluate the characteristics of a representative, wide-bandgap-based semiconductor material. The SWXRT installed in the 9D beamline of the Pohang accelerator laboratory has an eight-axis sample stage and three-axis detector motion and thus defects in wafers several inches in size in various XRT measurement modes. The SWXRT device not only accepts analog X-ray film, but also yields large-area panel images and data for high-resolution X-ray cameras. We used high-resolution X-ray film and a digital detector to rapidly acquire and analyze the diffraction image of the SiC substrate, which is a representative single-crystal power semiconductor. We expect the quality and defect information of various monocrystalline materials to increase in the near future.