Abstract: Apparatus and methods for complex imaging reflectometry and refractometry using at least partially coherent light. Quantitative images yield spatially-dependent, local material information about a sample of interest. These images may provide material properties such as chemical composition, the thickness of chemical layers, dopant concentrations, mixing between layers of a sample, reactions at interfaces, etc. An incident beam of VUV wavelength or shorter is scattered off of a sample and imaged at various angles, wavelengths, and/or polarizations. The power of beam is also measured. This data is used to obtain images of a sample's absolute, spatially varying, complex reflectance or transmittance, which is then used to determine spatially-resolved, depth-dependent sample material properties.

Abstract: Apparatus and methods for improved HHG of ultrashort pulse laser beams. A HHG assembly includes a gas distribution block and a waveguide cartridge having a HHG hollow core waveguide. The waveguide cartridge is attached to the gas distribution block and may be removed and replaced, while the gas distribution block remains affixed within the apparatus. The gas distribution block is configured to maintain a pressure profile within the hollow core fiber. The system also includes two operating beam sensors and two actuatable mirrors. The operating beam sensors are fixed with respect to the HHG assembly. The system is aligned before operation by adjusting the actuatable mirrors to optimize a sample beam through the waveguide and recording the position of the beam on the operating beam sensors. In operation, the mirrors are actuated to maintain the same positions of the input beam on the operating beam sensors.