A5102722153- Electron and X-Ray Spectroscopy Techniques
- Advancements in Photolithography Techniques
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Advanced Electron Microscopy Techniques and Applications
- Particle physics theoretical and experimental studies
- Nonlinear Dynamics and Pattern Formation
- Phase Equilibria and Thermodynamics
- Nanofabrication and Lithography Techniques
- Material Dynamics and Properties
- Ionic liquids properties and applications
- Plasma Diagnostics and Applications
- Force Microscopy Techniques and Applications
- Advancements in PLL and VCO Technologies
- Quantum Dots Synthesis And Properties
- Cold Atom Physics and Bose-Einstein Condensates
- Electrowetting and Microfluidic Technologies
- Advanced Thermoelectric Materials and Devices
- Radiation Detection and Scintillator Technologies
- Microfluidic and Bio-sensing Technologies
- Chemical Thermodynamics and Molecular Structure
- Electrostatics and Colloid Interactions
- Chalcogenide Semiconductor Thin Films
- Surface and Thin Film Phenomena
University of Oxford
2021-2025
University at Albany, State University of New York
2013
Fermi National Accelerator Laboratory
1975-2003
IBM (United States)
1989-1991
Hewlett-Packard (United States)
1979-1981
University of Chicago
1975-1976
Over the last half-century, direct measurements of surface forces have been instrumental in exploration a multitude phenomena liquid, soft, and biological matter. Measurements van der Waals interactions, electrostatic hydrophobic structural forces, depletion many other effects checked challenged theoretical predictions motivated new models understanding. The gold-standard instrument for these is
Water-in-salt electrolytes are a fascinating new class of highly concentrated aqueous solutions with wide electrochemical stability windows that make them viable as battery electrolytes. However, the high ion concentration water-in-salt means these systems poorly understood when compared to more dilute electrolyte solutions. Here, we present direct surface force measurements across thin films at several concentrations. We find adopts layered structure charged interfaces composed...
Zwitterionic osmolytes are widely known to have a protein-protective effect against high salt concentration, but mechanistic picture of osmolyte function remains elusive. Here total scattering is used determine...
Experimental measurements of interactions in ionic liquids and concentrated electrolytes over the past decade or so have revealed simultaneous monotonic oscillatory decay modes. These observations been hard to interpret using classical theories, which typically allow for just one electrostatic mode electrolytes. Meanwhile, substantial progress theoretical description dielectric response ion correlations has illuminated deep connection between density charge multiplicity modes characterising...
The importance of mutual repulsion beam electrons is investigated for conditions relevant to electron lithography. A Monte Carlo calculation has been performed which evaluates the spot size a given current and column geometry. results show that broadening due significantly limits density obtainable. Experimental are presented, agreement with theory excellent. For 21.5 cm long operating 3 mrad aperture semi-angle, was measured as .14 μm at 100 nA, .30 1 μA current. predicts an optimum exists...
The design of a high speed electron-beam lithography column is described. Designed for use with raster scan system, the produces beam current 600 nA in an 0.5 μm round spot, and has deflection field 5 mm2. uses zirconiated thermal emission cathode, two magnetic lenses, intermediate cross-over blanking purposes, two-stage electrostatic producing both precision. compatible 300 MHz pixel exposure rate accuracy better than ±0.125 (2σ).
Transverse beam profile measurement systems called flying wires have been installed and made operational in the Fermilab Main Ring Tevatron accelerators. A wire is a device that passes (flies) 25- mu m carbon filament through particle beam, transversely, at constant velocity of between 2 5 m/s. Collisions particles produce secondary cascades, which turn photons scintillator. photomultiplier tube an optical encoder are used to measure light intensity position, respectively. vs. transverse...
The attractiveness of electron beam systems would be greatly enhanced if the throughput could improved. One approach, described previously by authors employs a uniform axial magnetic field to focus thousands beams simultaneously [D. S. Pickard et al., J. Vac. Sci. Technol. B 21, 2709 (2003); T. R. Groves and A. Kendall, ibid., 16, 3168 (1998)]. beamlets never combine form common crossover, thereby avoiding limitations due space charge blurring. With this one challenge was fashion detection...
A fundamental limit on the current obtainable in an electron beam writing system is set by mutual repulsion of electrons. Computer Monte Carlo simulations take into account essential physical properties, which are discreteness charge, random nature problem, and many-body aspect. simulation has been used as a design tool for high throughput lithography at Hewlett-Packard. The column, successful operation, capable 0.6 μA 0.5 μm spot 20 kV. This resolution maintained over 5 mm square deflection...
Experimental measurements of interactions in ionic liquids and concentrated electrolytes over the past decade or so have revealed simultaneous monotonic oscillatory decay modes. These observations been hard to interpret using classical theories, which typically allow for just one electrostatic mode electrolytes. Meanwhile, substantial progress theoretical description dielectric response ion correlations has illuminated deep connection between density charge multiplicity modes characterising...
This paper constitutes a presentation of work in progress at discussion session the conference Dense ionic fluids Faraday Discussion, 8-10 July 2024, London, and is published on pages 293-295 Ref. [Faraday Discuss. volume 253, page 289].
We demonstrate reversible and switchable actuation using AC electric fields to bring two surfaces separated by a thin film of ionic fluid in out adhesive contact. Using surface force balance we apply normal crossed-cylinder contact measure directly the separation with sub-molecular resolution. Taking advantage oscillatory structural acting between across fluid, which show be unaffected field, pick distinct (quantized) states through precise tuning field. This proof-of-concept indicates...
Zn(O, S) has previously been demonstrated to be a viable replacement for the traditional CdS buffer layer in CIGS based thin-film photovoltaic devices. The deposition methods Zn-based layers include wet chemical bath deposition, PVD, ALD, and other techniques. This work focuses on evaluation of glass by sputtering. Results with RF reactive magnetron sputtering ZnS target Ar-O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> environment...
IBM’s new e-beam maskmaker, designated EL-3+, is installed and operating in the IBM Advanced Mask Facility Burlington, Vermont. This tool represents a significant extension state of art manufacture masks, particularly areas minimum feature size overlay. The routinely operates with 0.35 μm ground rules at 70 nm (3σ) registration to grid. has demonstrated ability work 0.25 as well. primary mission production 1X x-ray masks. Some parameters include 50 keV electron beam current density 20 A/cm2....
Six flying wire systems have been installed in the Fermilab Accumulator to measure transverse beam profiles during antiproton stacking and extraction, momentum distribution deceleration through transition. The authors summarize hardware software features of accumulator systems. Each system measures a profile by passing 25- mu carbon filament transversely, recording flux secondary particles which are produced from collisions between wire. motion, data acquisition, communication with control...
The space charge interaction in a beam can be approximated by summing the scattering between all possible pairs of electrons beam. An efficient algorithm is presented for exact solution to two-body Coulomb problem. This incorporated into Monte Carlo program simulate effects electron-beam lithography systems. results this are compared those obtained using numerical integration N-body We demonstrate that approach accurately models detailed physics currents common many state-of-the-art e-beam
The semiconductor industry is under constant pressure to reduce production costs even as the complexity of technology increases. Lithography represents most expensive process due its high capital equipment and implementation low-k1 lithographic processes, which have added making masks because greater use optical proximity correction, pixelated masks, double or triple patterning. Each these mask technologies allows semiconductors at future nodes while extending utility current immersion...