There is an urgent need for improvements in the manufacturing capabilities of high-efficiency and ultra-high-resolution gratings for X-ray spectroscopy. Specifically, there is a need for gratings with line-placement accuracy better than 10 nm root-mean-square (rms) over the entire optic. Current gratings take weeks to months to pattern and thermal and mechanical drifts cause unacceptable errors. In previous work, a technique was developed to write variable-line space gratings via electron-beam lithography and transfer the pattern into sawtooth profile groves. The viability of this technique will be evaluated for diffraction-limited X-ray sources via experimentation and metrology in Phase I. In Phase 1, preliminary gratings will be written via electron-beam lithography and the quality of the line placement over large areas will be measured. Furthermore, data of previous work demonstrating sawtooth profiles, will be analyzed and evaluated to determine if improvements are required for X-ray spectroscopy. Lastly a plan along with logistical requirements will be developed to integrate the fabrication techniques into a complete grating that meets all required specifications. The development of improved diffraction gratings for X-rays will enable scientist and engineers to better understand high-energy sources such as synchrotrons and plasmas. Gratings are critical for characterizing optics, wave-length dispersive spectroscopy, and focusing X-ray sources. If this work in carried beyond a Phase I into a Phase II or III and beyond, the public benefits will be vast. For example, gratings for wavelength-dispersive spectroscopy will improve our understanding of plasmas for fusion energy. Fusion energy provides one of the best solutions to the global warming crisis via providing a virtually limitless supply of clean energy. Plasma physics for fusion energy is extremely complex and improved diffraction gratings will enable scientist and engineers with better data. High-resolution gratings are also critical for studying the structures in materials via X-ray spectroscopy. Much of what we know about atomic structures is via spectroscopy and high-resolution gratin improve the fidelity of spectroscopic experiments.
