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Selective deoxygenation of graphene oxide has been conducted with regard with the design and fabrication of graphene based devices. The ion beam lithography is considered to be a powerful method for patterning onto graphene oxide foil. A helium beam has been used for both direct patterning onto graphene oxide foil and simultaneous online characterisation of its structural and compositional changes. Scanning electron microscopy, energy dispersive spectroscopy and Rutherford backscattering spectrometry analyses have been accurately employed to reveal and monitor the deoxygenation of the graphene oxide foil demonstrating the reliability of the direct patterning using the ion beam lithography technique. [ABSTRACT FROM AUTHOR]

A filament-powered multicusp ion source for production of H- has been developed for the Jyväskylä Pelletron accelerator for use in ion beam lithography and particle induced X-ray emission applications. The source can be considered conventional with the exception of the filter field being created with an electric magnet for continuous adjustability. A permanent magnet dipoleantidipole electron dump is integrated in the puller electrode. The source provides 50 μA H- beam at 10 keV energy with 0.019 mm mrad 95 % normalized rms emittance through a 2 mm aperture. Lower emittance is achievable by changing the plasma electrode insert to a smaller aperture one if application requires. A new commercial MCC30/15 cyclotron has been installed at the Jyväskylä accelerator laboratory providing 30MeV H+ and 15Mev D+ for use in nuclear physics experiments and applications. The ion source delivered with the cyclotron is a a filament-powered multicusp source capable of about 130 h continuous operation at 1 mA H- output between filament changes. The ion source is located in the cyclotron vault and therefore a significant waiting time for the vault cooldown is required before filament change is possible. This kind of operation is not acceptable as 350 h and longer experiments are expected. Therefore a project for developing a CW 13.56 MHz RF ion source has been initiated. A planar RF antenna replacing the filament back plate of the existing TRIUMF-type ion source has been used in the first tests with 240 μA of H- and 21 mA of electrons measured at 1.5 kW of RF power. Tests with higher RF power levels were prevented by electron beam induced sparking. A new plasma chamber has been built and a new extraction is being designed for the RF ion source. The extraction code IBSimu has recently gone through a major update on how smooth electrode surfaces are implemented in the Poisson solvers. This has made it possible to implement a fast multigrid solver with low memory consumption. Also a method has been made to import 3D CAD geometries into simulations. [ABSTRACT FROM AUTHOR]

Diffractive optical elements are important components for applications in soft x-ray and extreme ultraviolet radiation. At present, the standard fabrication method for such optics is based on electron beam lithography followed by nanostructuring. This requires a series of complex processes including exposure, reactive ion-etching, and electro-plating. We report on experiments showing the single-step fabrication of such elements using ion beam lithography. Both transmission and reflection gratings were fabricated and successfully implemented as spectrometers at laboratory soft x-ray sources. Additionally, first steps toward zone plate fabrication are described. [ABSTRACT FROM AUTHOR]

The University of Florida (UF) have collaborated with Raith to develop a version of the Raith ionLiNE IBL system that has the capability to deliver multi-ion species in addition to the Ga ions normally available. The UF system is currently equipped with a AuSi liquid metal alloy ion source (LMAIS) and ExB filter making it capable of delivering Au and Si ions and ion clusters for ion beam processing. Other LMAIS systems could be developed in the future to deliver other ion species. This system is capable of high performance ion beam lithography, sputter profiling, maskless ion implantation, ion beam mixing, and spatial and temporal ion beam assisted writing and processing over large areas (100 mm2)-all with selected ion species at voltages from 15-40 kV and nanometer precision. We discuss the performance of the system with the AuSi LMAIS source and ExB mass separator. We report on initial results from the basic system characterization, ion beam lithography, as well as for basic ion-solid interactions. [ABSTRACT FROM AUTHOR]

A plane mirror and two strongly curved plane elliptical mirrors comprising the refocusing system downstream the plane grating monochromator at FLASH in DESY have been characterized with the Nanometer Optical Component Measuring Machine at the BESSY-II Optics Laboratory of the Helmholtz Zentrum Berlin. Based on the measurement results the two elliptical cylinders were optimized by deterministic surface finishing technology (Ion Beam Finishing). The expected focusing performance was verified by ray tracings after each ion beam finish iteration using the measured topography results. [ABSTRACT FROM AUTHOR]

The fabrication of nano-dimensional features in the photoetchable glass FoturanTM, using focused ion beam technology has been characterized. To date, most microfabrication in this material has used UV lithography and UV lasers, with minimum feature size of around 10 μm determined by the grain structure, though there has been some recent work using high energy proton irradiation. Focused ion beam technology offers two potential advantages: features are etched directly without post bake or HF wet etch and features can be generated with lateral and depth resolution on the nanoscale. Initial test features were milled to a depth of 1.46 μm, without distortion due to charging, at a milling rate of 0.23 μm3/nC, in general agreement with our simulations. We further report for the first time the sputter yield rates of the Foturan when FIB milled using enhanced etch gasses. For the use of Iodine gas there was found to be no mill rate enhancement. Whereas for the Xenon difluoride gas, a roughly doubling of the sputter yield rate to 0.49 μm3/nC was found. [ABSTRACT FROM AUTHOR]

We developed a technique for element-specific magnetic hysteresis measurements with a 2.5-μm spatial resolution using a focused hard X-ray beam to study magnetic films with lateral microstructures. This technique was applied to a 100-nm-square magnetic dot array fabricated by focused ion beam lithography in an 8 × 8 μm area on a CoPt film. Measured magnetic hysteresis curves illustrated the notable change in magnetic reversal process of the dots, induced by cutting a continuous film into isolated dots. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Currently the emission of both Xe and Sn are being investigated as sources for EUV lithography. In Xe the bulk of the emission in the region of interest, 13.5 nm, originates from one ion stage, Xe XI, while in Sn, the emission at this wavelength arises from resonance transitions in a range of stages and thus is potentially more intense. However essentially no data for these ions exists making modeling of the plasma processes involved and estimation of the conversion efficiencies attainable and their dependence on experimental parameters extremely difficult. Here we provide an overview of some recent results obtained by our group and compare them with data from other researchers. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We fabricated a robust and high aspect ratio tungsten deposited tip (TD tip) using a Focused Ion Beam (FIB). This tip was well controlled during fabrication. Tip diameter is uniform at around 90nm and its growing length is proportional to the irradiation time of the ion beam. Tip shape is a cylindrical pillar and aspect ratio (length/diameter) is greater than 10. Growing angle of the tip is identical to the incident angle of the ion beam. Critical dimension (CD) measurement of shallow trench isolation (STI) was performed using this tip. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]