scholarly journals EUV-Induced Plasma: A Peculiar Phenomenon of a Modern Lithographic Technology

2019 ◽  
Vol 9 (14) ◽  
pp. 2827 ◽  
Author(s):  
Beckers ◽  
Ven ◽  
Horst ◽  
Astakhov ◽  
Banine
Keyword(s):  
Rarefied Gas ◽  
Extreme Ultraviolet ◽  
Construction Materials ◽  
Optical Surfaces ◽  
Major Interest ◽  
Current Article ◽  
Plasma Characteristics ◽  
Euv Spectrum ◽  
Distinguishing Features ◽  
Peculiar Phenomenon

After a long period of relatively low interest, science related to effects in the Extreme Ultraviolet (EUV) spectrum range experienced an explosive boom of publications in the last decades. A new application of EUV in lithography was the reason for such a growth. Naturally, an intensive development in such area produces a snowball effect of relatively uncharted phenomena. EUV-induced plasma is one of those. While being produced in the volume of a rarefied gas, it has a direct impact onto optical surfaces and construction materials of lithography machines, and thus has not only scientific peculiarity, but it is also of major interest for the technological application. The current article provides an overview of the existing knowledge regarding EUV-induced plasma characteristics. It describes common, as well as distinguishing, features of it in comparison with other plasmas and discusses its interaction with solid materials. This article will also identify the gaps in the existing knowledge and it will propose ways to bridge them.

Contamination rates of optical surfaces at 157 nm: impurities outgassed from construction materials and from photoresists

2003 ◽  
Author(s):  
Theodore M. Bloomstein ◽  
Jan H. C. Sedlacek ◽  
Stephen T. Palmacci ◽  
Dennis E. Hardy ◽  
Vladimir Liberman ◽  
...  
Keyword(s):  
Construction Materials ◽  
Optical Surfaces

Degradation in Euv Reflectance of Ion-Sputtered Sic Films

1994 ◽  
Vol 354 ◽  
Author(s):  
Dan Schwarcz ◽  
Ritva A.M. Keski-Kuha
Keyword(s):  
Thin Films ◽  
Silicon Carbide ◽  
Chemical Vapor Deposition ◽  
High Temperature ◽  
Vapor Deposition ◽  
Extreme Ultraviolet ◽  
Chemical Vapor ◽  
Optical Components ◽  
Optical Surfaces ◽  
Sic Films

AbstractSilicon Carbide (SiC) formed by chemical vapor deposition (CVD) has the highest reflectivity in the extreme ultraviolet (EUV) of any currently used optical material. The high temperature required for the CVD process, however, limits its suitability for coating optical components. To address this problem thin films have been sputtered onto optical surfaces from CVD βSiC targets. These films, while having reflectivity lower than that of CVD SiC, are nonetheless the best coatings available for reflectance in the spectral region below 1000À. While the initial properties are good, the EUV reflectivity degrades with time after deposition. A relative decrease of about 25% is evident in the reflectivity at 920Â after 2.5 years, and about 85% of this change occurs in the first three months. In fact, a decrease is observed in the minutes following deposition. In this study the degradation is characterized and a mechanism is proposed. Efforts underway to reduce or eliminate the degradation are discussed.

scholarly journals EUVE and VLA Observations of the Eclipsing Pre-Cataclysmic Variable V471 Tauri

1996 ◽  
Vol 152 ◽  
pp. 349-354
Author(s):  
S.L. Cully ◽  
J. Dupuis ◽  
T. Rodriguez-Bell ◽  
G. Basri ◽  
O.H.W. Siegmund ◽  
...  
Keyword(s):  
White Dwarf ◽  
Extreme Ultraviolet ◽  
Magnetic Loop ◽  
Pure Hydrogen ◽  
Very Large Array ◽  
Hyades Cluster ◽  
Hydrogen Column Density ◽  
Orbital Phase ◽  
Coronal Magnetic Loop ◽  
Euv Spectrum

We present observations of the eclipsing binary V471 Tauri by the Extreme Ultraviolet Explorer (EUVE) and the Very Large Array (VLA). The EUV spectrum is dominated by the continuum of the hot white dwarf and the time-averaged spectrum is fitted by a 33.1 ± 0.5 × 103 K pure hydrogen white dwarf atmosphere assuming log g = 8.5. An ISM hydrogen column density of 1.5 ± 0.4 × 1018 cm−2 is required to explain the attenuation of the white dwarf spectrum thus setting the HI column in the line of sight of the Hyades cluster. The He II λ304 Å line is in emission and varies over the orbital period of V471 Tauri following a sinusoidal modulation with the maximum reached when the K star is at inferior conjunction. Transient dips are detected at orbital phase −0.12 in the SW and MW spectrometers integrated lightcurves but are notably absent in the LW lightcurve indicating the occulting material is ionized. The VLA observation suggest the presence of a K star coronal magnetic loop between the two stars reconnecting with the white dwarf magnetic field. Such a structure could be the occulting source needed to explain the dips seen in the lightcurves of V471 Tauri in the EUV.

Dual Ion Beam Sputtering of Carbides for EUV Reflectance

1995 ◽  
Vol 396 ◽  
Author(s):  
Dan Schwarcz ◽  
R.A.M. Keski-Kuha
Keyword(s):  
Boron Carbide ◽  
Extreme Ultraviolet ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
Optical Surfaces ◽  
Sputtered Films ◽  
Ion Beam Assisted Deposition ◽  
Beam Sputtering ◽  
Dual Ion Beam Sputtering ◽  
Sic Films

AbstractThere is a need for thin optical coatings that can be produced at low temperatures and have a high reflectance at the extreme ultraviolet (EUV), λ < 1200 Å. Currently, the best such materials are silicon carbide (SiC) and boron carbide sputtered onto optical surfaces. The EUV reflectance of sputtered SiC, however, is not as high as that of the sputtered target materials (sintered or CVD -SiC). More significantly, the reflectance of both sputtered films degrades with time. In previous work the reflectance degradation of the SiC films has been quantified, and efforts to ameliorate it via ion-beam assisted deposition (BAD) were described. Further work on sputtered SiC films is reported, including chemical and structural analysis. In addition, the degradation behavior of sputtered boron carbide is discussed.

Encultured minds, not error reduction minds

2020 ◽  
Vol 43 ◽  
Author(s):  
Robert Mirski ◽  
Mark H. Bickhard ◽  
David Eck ◽  
Arkadiusz Gut
Keyword(s):  
Free Energy ◽  
Error Reduction ◽  
Energy Principle ◽  
Free Energy Principle ◽  
Current Article

Abstract There are serious theoretical problems with the free-energy principle model, which are shown in the current article. We discuss the proposed model's inability to account for culturally emergent normativities, and point out the foundational issues that we claim this inability stems from.

A standard for transmission electron spectroscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 530-531 ◽  
Author(s):  
Dennis Maher ◽  
David Joy ◽  
Peggy Mochel
Keyword(s):  
Thin Films ◽  
Electron Spectroscopy ◽  
Host Lattice ◽  
Single Element ◽  
Multicomponent Systems ◽  
Transmission Electron ◽  
Major Interest ◽  
Standard Specimens ◽  
Forms Of Carbon ◽  
Electron Energy Loss

A variety of standard specimens is needed in order to systematically investigate the instrumentation, specimen, data reduction and quantitation variables in electron energy-loss spectroscopy (EELS). Pure single element specimens (e.g. various forms of carbon) have received considerable attention to date but certain elements of interest cannot be prepared directly as thin films. Since studies of the first and second row elements in two- or multicomponent systems will be of considerable importance in microanalysis using EELS, there is a need for convenient standards containing these species. For many investigations a standard should contain the desired element, or elements, homogeneously dispersed through a suitable matrix and at an accurately known concentration. These conditions may be met by the technique of implantation.Silicon was chosen as the host lattice since its principal ionization energies, EL23 = 98 eV and Ek = 1843 eV, are well removed from the K-edges of most elements of major interest such as boron (Ek = 188 eV), carbon (Ek = 283 eV), nitrogen (Ek = 400 eV) and oxygen (Ek = 532 eV).

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Bayesian removal of noise for increased sensitivity in vector pattern recognition lattice imaging of interfaces

1993 ◽  
Vol 51 ◽  
pp. 994-995
Author(s):  
L. Fei ◽  
P. Fraundorf
Keyword(s):  
Pattern Recognition ◽  
Perfect Crystal ◽  
Unit Cell ◽  
Ion Milling ◽  
Beam Radiation ◽  
Major Interest ◽  
Unit Cells ◽  
Mapping Process ◽  
Increased Sensitivity ◽  
Electron Microscopes

Interface structure is of major interest in microscopy. With high resolution transmission electron microscopes (TEMs) and scanning probe microscopes, it is possible to reveal structure of interfaces in unit cells, in some cases with atomic resolution. A. Ourmazd et al. proposed quantifying such observations by using vector pattern recognition to map chemical composition changes across the interface in TEM images with unit cell resolution. The sensitivity of the mapping process, however, is limited by the repeatability of unit cell images of perfect crystal, and hence by the amount of delocalized noise, e.g. due to ion milling or beam radiation damage. Bayesian removal of noise, based on statistical inference, can be used to reduce the amount of non-periodic noise in images after acquisition. The basic principle of Bayesian phase-model background subtraction, according to our previous study, is that the optimum (rms error minimizing strategy) Fourier phases of the noise can be obtained provided the amplitudes of the noise is given, while the noise amplitude can often be estimated from the image itself.

Noise-Induced Balance Loss? Rethinking Clinical Implications of Noise Exposure

2019 ◽  
Vol 4 (6) ◽  
pp. 1418-1422
Author(s):  
Bre Myers ◽  
J. Andrew Dundas
Keyword(s):  
Vestibular System ◽  
Noise Exposure ◽  
Balance Control ◽  
Scope Of Practice ◽  
Hearing Conservation ◽  
Exposed Population ◽  
Auditory Systems ◽  
Current Article ◽  
Balance Loss ◽  
Cross System

Purpose The primary aim of the current article is to provide a brief review of the literature regarding the effects of noise exposure on the vestibular and balance control systems. Although the deleterious effects of noise on the auditory system are widely known and continue to be an active area of research, much less is known regarding the effects of noise on the peripheral vestibular system. Audiologists with working knowledge of how both systems interact and overlap are better prepared to provide comprehensive care to more patients as assessment of both the auditory and vestibular systems has been in the audiologists' scope of practice since 1992. Method A narrative review summarizes salient findings from the archival literature. Results Temporary and permanent effects on vestibular system function have been documented in multiple studies. Hearing conservation, vestibular impairment, and fall risk reduction may be more intimately related than previously considered. Conclusions A full appreciation of both the vestibular and auditory systems is necessary to address the growing and aging noise-exposed population. More cross-system studies are needed to further define the complex relationship between the auditory and vestibular systems to improve comprehensive patient care.

First-Person Experiments in Thinking

2018 ◽  
Vol 23 (3) ◽  
pp. 189-205 ◽  
Author(s):  
Renatus Ziegler ◽  
Ulrich Weger
Keyword(s):  
Physiological Parameters ◽  
The Self ◽  
First Person ◽  
Psychological Phenomena ◽  
Third Person ◽  
Current Article ◽  
Thinking Process ◽  
Mental Contents

Abstract. In psychology, thinking is typically studied in terms of a range of behavioral or physiological parameters, focusing, for instance, on the mental contents or the neuronal correlates of the thinking process proper. In the current article, by contrast, we seek to complement this approach with an exploration into the experiential or inner dimensions of thinking. These are subtle and elusive and hence easily escape a mode of inquiry that focuses on externally measurable outcomes. We illustrate how a sufficiently trained introspective approach can become a radar for facets of thinking that have found hardly any recognition in the literature so far. We consider this an important complement to third-person research because these introspective observations not only allow for new insights into the nature of thinking proper but also cast other psychological phenomena in a new light, for instance, attention and the self. We outline and discuss our findings and also present a roadmap for the reader interested in studying these phenomena in detail.

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