Large Diffraction Grade Single Crystal Diamonds Grown by CVD

Large size diffraction-grade diamond is needed for high scientific impact applications at synchrotron and Free-Electron Laser (FEL) X-ray sources, stemming from diamond’s unique physical properties in low atomic number and extremely high thermal diffusivity Sufficiently large diffraction-grade diamond crystals, similar in crystalline quality to that of silicon, are required for the fabrication of X-ray optical elements in various crystallographic orientations, thicknesses, and shapes for monochromators, beam splitters, high-reflectance cavity mirrors for various FEL oscillator schemes, phase plates, spectrometers, etc With high repetition-rate X-ray FELs and near diffraction-limited storage rings X-ray sources due to come on line in the near future, there will be even greater demand for their availability Presently, there are no suppliers in the United States (US) to support this rapidly developing field of diamond X-ray optics applications for the next generation sources Such a supplier is needed to support this important application space Microwave plasma chemical vapor deposition technology (CVD) will be applied in innovative process windows to high quality diamond seeds to prepare state of the art diffraction grade materials The Phase I objective is to prove that CVD technology can be used in combination with proper diamond seed selection and preparation to create diffraction grade single crystal diamond in manner that is scalable in terms of diamond crystal thickness and area Two different innovative CVD approaches will be applied to square high pressure high temperature (HPHT) diamond seeds of lateral dimensions of 3 to 4 mm on edge to create 3 to 4 mm thick CVD overgrown diamond The overgrown diamond will be removed from the seed, prepared, and tested for its diffraction grade potential via in-house characterization at MSU plus advanced x-ray diffraction experiments at Argonne National Laboratory’s Advanced Photon Source Success in this effort will remove a major supply chain challenge for advanced beam line research today and pave the way to support its ever increasingly stringent requirements for more advanced research in the future Other industries that could benefit from the proposed technology include x-ray based cancer therapy and x-ray based sensors for homeland security at national borders