@article{ae2c6050003f4d278939cf04d9eb2703,
title = "Tunable hard x-ray nanofocusing with Fresnel zone plates fabricated using deep etching",
abstract = "Fresnel zone plates are used widely for x-ray nanofocusing, due to their ease of alignment and energy tunability. Their spatial resolution is limited in part by their outermost zone width drN, while their efficiency is limited in part by their thickness tzp. We demonstrate the use of Fresnel zone plate optics for x-ray nanofocusing with drN = 16 nm outermost zone width and a thickness of about tzp = 1.8 µm (or an aspect ratio of 110) with an absolute focusing efficiency of 4.7% at 12 keV, and 6.2% at 10 keV. Using partially coherent illumination at 12 keV, the zone plate delivered a FWHM focus of 46 × 60 nm at 12 keV, with the first-order coherent mode in a ptychographic reconstruction showing a probe size of 16 nm FWHM. These optics were fabricated using a combination of metal-assisted chemical etching and atomic layer deposition for the diffracting structures, and silicon wafer back-thinning to produce optics useful for real applications. This approach should enable new higher resolution views of thick materials, especially when energy tunability is required.",
author = "Kenan Li and Sajid Ali and Michael Wojcik and {de Andrade}, Vincent and Xiaojing Huang and Hanfei Yan and Chu, {Yong S.} and Evgeny Nazaretski and Ajith Pattammattel and Chris Jacobsen",
note = "Funding Information: Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. We thank the National Institute of Mental Health, National Institutes of Health, for support under grant R01 MH115265. Funding Information: Acknowledgment. This research used resources of the Advanced Photon Source and the Center for Nanoscale Materials, U.S. Department of Energy (DOE) Office of Science User Facilities operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. It also used the HXN beamline of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Funding Information: Basic Energy Sciences (DE-AC02-06CH11357, DE-SC0012704); National Institute of Mental Health (R01-MH115265). This research used resources of the Advanced Photon Source and the Center for Nanoscale Materials, U.S. Department of Energy (DOE) Office of Science User Facilities operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. It also used the HXN beamline of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. We thank the National Institute of Mental Health, National Institutes of Health, for support under grant R01 MH115265. Publisher Copyright: Journal {\textcopyright} 2020 Optical Society of America",
year = "2020",
month = may,
day = "25",
doi = "10.1364/OPTICA.387445",
language = "English (US)",
volume = "7",
pages = "410--416",
journal = "Optica",
issn = "2334-2536",
publisher = "OSA Publishing",
number = "5",
}