A5051690847- Advanced X-ray Imaging Techniques
- Advancements in Photolithography Techniques
- Electron and X-Ray Spectroscopy Techniques
- Astrophysical Phenomena and Observations
- X-ray Spectroscopy and Fluorescence Analysis
- Calibration and Measurement Techniques
- Surface Roughness and Optical Measurements
- Optical Coatings and Gratings
- Metal and Thin Film Mechanics
- Solar and Space Plasma Dynamics
- Photocathodes and Microchannel Plates
- Stellar, planetary, and galactic studies
- Particle Detector Development and Performance
- Advanced Surface Polishing Techniques
- Semiconductor materials and interfaces
- Copper Interconnects and Reliability
- Adaptive optics and wavefront sensing
- Silicon and Solar Cell Technologies
- Gamma-ray bursts and supernovae
- Thin-Film Transistor Technologies
- Particle Accelerators and Free-Electron Lasers
- Astro and Planetary Science
- Integrated Circuits and Semiconductor Failure Analysis
- CCD and CMOS Imaging Sensors
- Ion-surface interactions and analysis
Reflective X Ray Optics
2015-2024
Columbia University
2000-2008
K Lab (United States)
1988-2005
Universities Space Research Association
2004
California Institute of Technology
1999-2003
Danish Meteorological Institute
1999
Nokia (United States)
1989-1998
AT&T (United States)
1990-1995
University of Colorado Boulder
1985-1989
Laboratory for Atmospheric and Space Physics
1984-1988
The Atmospheric Imaging Assembly (AIA) provides multiple simultaneous high-resolution full-disk images of the corona and transition region up to 0.5 R ⊙ above solar limb with 1.5-arcsec spatial resolution 12-second temporal resolution. AIA consists four telescopes that employ normal-incidence, multilayer-coated optics provide narrow-band imaging seven extreme ultraviolet (EUV) band passes centered on specific lines: Fe xviii (94 Å), viii, xxi (131 ix (171 xii, xxiv (193 xiv (211 He ii (304...
A computer program called IMD is described. used for modeling the optical properties (reflectance, transmittance, electric-field intensities, etc.) of multilayer films, i.e., films consisting any number layers thickness. includes a full graphical user interface and affords with up to eight simultaneous independent variables, as well parameter estimation (including confidence interval generation) using nonlinear, least-squares curve fitting user-supplied experimental data. The computation...
The Atmospheric Imaging Assembly (AIA) instrument onboard the Solar Dynamics Observatory (SDO) is an array of four normal-incidence reflecting telescopes that image Sun in ten EUV and UV wavelength channels. We present initial photometric calibration AIA, based on preflight measurements response telescope components. estimated accuracy order 25%, which consistent with results comparisons full-disk irradiance spectral models. also describe characterization performance, including resolution,...
We demonstrate high resolution reduction imaging in the soft x-ray spectral region using multilayer-coated reflective optics. In particular, a Schwarzschild objective was used at 20:1 with 14 nm radiation to image line and space features from transmission mask onto resist-coated silicon wafer better than 0.1 μm. The mirrors of were coated Mo/Si multilayers provide nearly 40% reflectance near-normal incidence for radiation. Our results that multilayer coatings are capable enhancing optical...
Reflectance vs incidence angle measurements have been performed from 24 A to 1216 on electron-beam evaporated samples of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Os, Ir, Pt, and Au, using a nonlinear least-squares curve-fitting technique, the optical constants determined. Independently measured values incident beam polarization, film thicknesses, surface roughnesses are incorporated into derivation constants. Additionally, Auger electron spectroscopy depth profiling each sample...
Abstract The third flight of the High-Resolution Coronal Imager (Hi-C 2.1) occurred on May 29, 2018; Sounding Rocket was launched from White Sands Missile Range in New Mexico. instrument has been modified its original configuration 1) to observe solar corona a passband that peaks near 172 Å, and uses new, custom-built low-noise camera. targeted Active Region 12712, captured 78 images at cadence 4.4 s (18:56:22 – 19:01:57 UT; 5 min 35 observing time). image spatial resolution varies due...
A method for deriving optical constants from reflectance vs angle of incidence measurements using a nonlinear least-squares curve-fitting technique based on the χ2 test fit is presented and used to derive several thin-film materials. The incorporates independently measured values film surface roughness, thickness, incident beam polarization. also provides direct estimating probable errors in derived constants. Data are 24 Å 1216 samples C, synthetic diamond, Al, Si, CVD SiC. Auger electron...
We describe the development of depth-graded W/Si multilayer films prepared by magnetron sputtering for use as broad-band reflective coatings hard x-ray optics. have used specular and nonspecular reflectance analysis to characterize interface imperfections in both periodic structures, high-resolution transmission electron microscopy (TEM) selected area diffraction (SAED) structure layer morphology a function depth an optimized multilayer. From we find widths range σ=0.275–0.35 nm deposited at...
The Solar Ultraviolet Imager (SUVI) is one of the several instruments that will fly on board next generation Geostationary Operational Environmental Satellites R-U platforms, as part National Oceanic and Atmospheric Administration's space weather monitoring fleet. SUVI a generalized Cassegrain telescope employs multilayer-coated optics operate in six extreme ultraviolet (EUV) narrow bandpasses centered at 93.9, 131.2, 171.1, 195.1, 284.2 303.8 Å. innovation design first EUV solar has...
A new extreme ultraviolet (EUV) multilayer coating has been developed comprising Pd and Y layers with thin B4C barrier at each interface, for normal incidence applications near 10 nm wavelength. Periodic, nonperiodic, dual-stack coatings have investigated compared similar structures either Mo/Y or Pd/B4C bilayers. We find that Pd/B4C/Y multilayers provide higher reflectance than Pd/B4C, much lower film stress Pd/B4C. also the performance of periodic repetitions Pd/Y, Ru/Y, Ru/B4C/Y, as well...
We have combined experiments and atomistic modeling in order to better understand the growth structure of metal films deposited onto sidewalls trenches vias. Using x-ray reflectance, atomic force microscopy, high-resolution transmission electron microscopy characterize microstructure morphology Ta grown by magnetron sputtering inclined substrates, we find that at larger incidence angles tend towards columnar with high roughness low density. used a three-dimensional Monte Carlo model (ADEPT)...
Amorphous silicon carbide films formed by sputtering techniques are shown to have high reflectance in the extreme ultraviolet spectral region. X-ray scattering verifies that atomic arrangements these amorphous, while Auger electron spectroscopy and Rutherford backscattering show composition close stoichiometric SiC, although slightly C-rich, with low impurity levels. Reflectance vs incidence angle measurements from 24 1216 A were used derive optical constants of this material, which...
The NuSTAR mission will be the first to carry a hard X-ray(5-80 keV) focusing telescope orbit. optics are based on use of multilayer coated thin slumped glass. Two different material combinations were used for flight optics, namely W/Si and Pt/C. In this paper we describe entire coating effort including final design that was two optics. We also present data performance verification coatings both Si witness samples as well individual mirrors.
We report on the performance, structure and stability of periodic multilayer films containing silicon carbide (SiC) aluminum (Al) layers designed for use as reflective coatings in extreme ultraviolet (EUV). find that SiC/Al multilayers prepared by magnetron sputtering have low stress, good temporal thermal stability, provide performance EUV, particularly applications requiring a narrow spectral bandpass, such monochromatic solar imaging. Transmission electron microscopy reveals amorphous SiC...
The structural and optical properties of Mo/Si Ru/Si x-ray multilayers prepared by sputter deposition in argon have been examined using high-resolution transmission electron microscopy, profilometry, soft reflectance. We find that for Ru/Si, similar to previous results Mo/Si, lower pressure during smoother layers higher For low-pressure deposited multilayers, interfacial roughness is negligible compared diffuseness; the presence amorphous interlayer regions both these systems major cause reduced
We have developed a magnetron sputtering system for the deposition of Mo/Si multilayer (ML) coatings onto large-area, figured optics, as required imaging in practical, extreme-ultraviolet (EUV) lithography tool. Coating uniformity on optics is adjusted by implementing contoured, shaped baffles during ML deposition. also an EUV reflectometer that capable measuring reflectance versus wavelength across surface these so coating can be determined with precision. discuss requirements practical...
We compare the reflectance and stability of multilayers comprising either Si/Mo, Si/Mo2C, Si/B4C, Si/C, or Si/SiC bilayers, designed for use as extreme-ultraviolet (EUV) reflective coatings. The films were deposited by using magnetron sputtering characterized both x-ray EUV reflectometry. find that new multilayer offers greatest spectral selectivity at longer wavelengths, well thermal stability. also describe optimization Solar-B EIS instrument. Finally, we experimental data with...
The stresses in periodic Mo/Si, W/Si, and Mo/C multilayer films were determined from wafer-curvature measurements. layer thickness of each material was varied systematically, parametric stress contours generated, showing constant the two-dimensional parameter space. These results illustrate that net a is not an intrinsic property film (for specific deposition conditions) but, rather, depends strongly on individual thicknesses. X-ray diffraction measurements show (a) how lattice spacing W Mo...
We present an overview of currently available EUV multilayer coatings that can be used for the construction solar physics instrumentation utilizing normal-incidence optics. describe performance a variety Si-based multilayers, including Si/B<sub>4</sub>C and new Si/SiC films provide improved in wavelength range from 25 n 35 nm, as well traditional Si/Mo broad-band recently developed Solar-B/EIS instrument. also outline prospects operation at both longer shorter wavelengths, potential...
We have investigated the stress and roughness in W/B<sub>4</sub>C X-ray multilayer films grown by reactive DC magnetron sputtering a nitrogen-argon gas mixture. also studied properties of single-layer W B<sub>4</sub>C films, order to understand specifically how stress, roughness, chemical composition microstructure these materials depends on sputter composition. find that both deposited reactively is reduced substantially; we corresponding improvement performance case designed operate at...
In this work we present the design of a Pd/B 4 C multilayer structure optimized for high reflectance at 6.67 nm.The has been deposited and also characterized along one year in order to investigate its temporal stability.This coating developed beam transport system FERMI@Elettra Free Electron Laser: use an additional aperiodic capping layer on top combines with filter properties useful rejecting fundamental harmonic when goal is select third FEL harmonic.
The High-Energy X-ray Probe (HEX-P) is a probe-class next-generation high-energy mission concept that will vastly extend the reach of broadband observations. Studying 2-200 keV energy range, HEXP has 40 times sensitivity any previous in 10-80 band, and be first focusing instrument 80-200 band. A successor to Nuclear Spectroscopic Telescope Array (NuSTAR), NASA Small Explorer launched 2012, HEX-P addresses key science objectives, serve as an important complement ESA's L-class Athena mission....