In spite of strict limits on outgassing from organic materials, some spacecraft instruments making long-term measurements of solar extreme ultraviolet (EUV) radiation still suffer significant degradation. While such measures have reduced the rate of degradation, they have not completely eliminated it in some cases. For example, in five years, the aluminum filters used in the (EVE) instruments onboard the (SDO) suffered losses exceeding 40% at 30.
View Article and Find Full Text PDFJ Vac Sci Technol A
December 2020
Carbon contamination induced by ultraviolet (UV) radiation affects precision optics in applications as diverse as semiconductor lithography and satellite observations of the Sun. Our previous experiments have shown that low-intensity UV-induced surface contamination depends quasi-logarithmically on the partial pressure of the organic contaminant due to the poly-dispersive nature of the surface-adsorbate system. This complex dependence presents difficulties because, without a physically motivated model, it cannot be extrapolated to low pressures.
View Article and Find Full Text PDFRev Sci Instrum
November 2015
We investigated several types of thin-film filters for high intensity work in the extreme-ultraviolet (EUV) spectral range. In our application, with a peak EUV intensity of 2.7 W cm(-2), Ni-mesh-backed Zr filters have a typical lifetime of 20 h, at which point they suffer from pinholes and a 50% loss of transmission.
View Article and Find Full Text PDFThe National Institute of Standards and Technology operates two spectral comparator facilities, both of which are used to provide detector calibrations from the ultraviolet to the near-infrared spectral range. One, the Ultraviolet Spectral Comparator Facility (UV SCF), has been in operation for more than two decades, providing one of the core calibration services. Recently, the illumination source used in the UV SCF has been changed from an argon mini-arc source to a laser-driven plasma light source.
View Article and Find Full Text PDFBefore being used in an extreme-ultraviolet (EUV) scanner, photoresists must first be evaluated for sensitivity and tested to ensure that they will not contaminate the scanner optics. The new NIST facility described here provides data on the contamination potential of the outgas products of a candidate resist by simultaneously irradiating a multilayer optic and a nearby resist-coated wafer with EUV radiation. The facility can also be used without changing its configuration to provide accurate resist dose-to-clear measurements.
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