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An analysis of blind ptychography that provides predictions of error and the reconstructed field-of-view (FOV) is presented. The utility of this analysis is demonstrated with a new approach called dual-grid ptychography that maximizes the FOV.

A new imaging technique enables nondestructive, 3D characterization of nanostructures, their composition, and interfaces., Next-generation nano- and quantum devices have increasingly complex 3D structure. As the dimensions of these devices shrink to the nanoscale, their performance is often governed by interface quality or precise chemical or dopant composition. Here, we present the first phase-sensitive extreme ultraviolet imaging reflectometer. It combines the excellent phase stability of coherent high-harmonic sources, the unique chemical sensitivity of extreme ultraviolet reflectometry, and state-of-the-art ptychography imaging algorithms. This tabletop microscope can nondestructively probe surface topography, layer thicknesses, and interface quality, as well as dopant concentrations and profiles. High-fidelity imaging was achieved by implementing variable-angle ptychographic imaging, by using total variation regularization to mitigate noise and artifacts in the reconstructed image, and by using a high-brightness, high-harmonic source with excellent intensity and wavefront stability. We validate our measurements through multiscale, multimodal imaging to show that this technique has unique advantages compared with other techniques based on electron and scanning probe microscopies.

We present a versatile, ptychographic phase-sensitive imaging EUV reflectometer that can nondestructively image samples with spatial, depth and compositional resolution, with sensitivities to dopant levels and interface quality.

We present a tabletop-scale complex-imaging EUV reflectometer that uses grazing- incidence ptychographic imaging to non-destructively determine depth-dependent, spatially-resolved composition with high sensitivity to chemical makeup, thin film layer thickness, interface quality and dopant profiles.

With increasingly 3D devices becoming the norm, there is a growing need in the semiconductor industry and in materials science for high spatial resolution, non-destructive metrology techniques capable of determining depth-dependent composition information on devices. We present a solution to this problem using ptychographic coherent diffractive imaging (CDI) implemented using a commercially available, tabletop 13 nm source. We present the design, simulations, and preliminary results from our new complex EUV imaging reflectometer, which uses coherent 13 nm light produced by tabletop high harmonic generation. This tool is capable of determining spatially-resolved composition vs. depth profiles for samples by recording ptychographic images at multiple incidence angles. By harnessing phase measurements, we can locally and nondestructively determine quantities such as device and thin film layer thicknesses, surface roughness, interface quality, and dopant concentration profiles. Using this advanced imaging reflectometer, we can quantitatively characterize materials-sciencerelevant and industry-relevant nanostructures for a wide variety of applications, spanning from defect and overlay metrology to the development and optimization of nano-enhanced thermoelectric or spintronic devices.

We present high-resolution, simultaneous two-color phase-and-amplitude characterization of 2nd harmonic up-conversion in OAM beams by ptychography. We measure topological charge conservation during 2nd harmonic generation process, which can be extended to high-order harmonic upconversion.