Browsing by Author "Ertas, G."
Now showing items 1-17 of 17
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Charging / discharging of thin PS / PMMA films as probed by dynamic x-ray photoelectron spectroscopy
(2007)Polystyrene / polymethyl methacrylate (PS-PMMA) thin films were analyzed for detecting phase separation as well as probing their electrical responses by XPS. It was also shown that electrical parameters like resistance or ... -
Concentric ring structures as efficient SERS substrates
(Institute of Electrical and Electronics Engineers, 2013)Plasmonic nanopatterned structures that can work as highly efficient surface-enhanced Raman scattering (SERS) substrates are presented in this study. A 'coupled' concentric ring structure has been designed, fabricated, ... -
Differential charging in SiO2/Si systems as determined by XPS
(American Chemical Society, 2004)The Si2p binding and the SiKLL kinetic energy difference between the SiO2 layer and Si substrate is shown to be influence by application of external voltage bias to the sample holder due to the differential charging as was ... -
Differentiation of domains in composite surface structures by charge-contrast x-ray photoelectron spectroscopy
(2007)An external bias is applied to two samples containing composite surface structures, while recording an XPS spectrum. Altering the polarity of the bias affects the extent of differential charging in domains that are chemically ... -
E-Beam lithography designed substrates for surface enhanced Raman spectroscopy
(Elsevier BV, 2015-06)Surface Enhanced Raman Spectroscopy (SERS) is a popular method that amplifies weak Raman signals from Raman-active analyte molecules making use of certain specially-prepared metallic surfaces. The main challenge in SERS ... -
Effect of solvent refractive index on the surface plasmon resonance nanoparticle optical absorption
(2007)Optical properties of plasmon coupled silver and gold nanoparticles were studied as a function of the refractive index of the surrounding medium. Our studies confirmed that the effect of changes in the refractive index of ... -
Enhanced peak separation in XPS with external biasing
(Elsevier, 2005-08-15)We have demonstrated that the An 4f peaks of the capped gold nanoparticles deposited on a SiO2 (20 nm)/Si substrate can be separated form the An 4f peaks of a gold metal strip, in contact with the same sample, by application ... -
'Fairy Chimney'-Shaped Tandem Metamaterials as Double Resonance SERS Substrates
(Wiley-VCH Verlag, 2012-10-12)A highly tunable design for obtaining double resonance substrates to be used in surface-enhanced Raman spectroscopy is proposed. Tandem truncated nanocones composed of Au-SiO2-Au layers are designed, simulated and fabricated ... -
Heating of magnetic fluid systems driven by circularly polarized magnetic field
(Elsevier BV * North-Holland, 2010)A theory is presented to calculate the heat dissipation of a magnetic suspension, a ferrofluid, driven by circularly polarized magnetic field. Theory is tested by in vitro experiments and it is shown that, regardless of ... -
Methods for probing charging properties of polymeric materials using XPS
(2010)Various thin polystyrene, PS, and poly(methyl methacrylate), PMMA and PS + PMMA blend films have been examined using the technique of recording X-ray photoelectron spectrum while the sample is subjected to ±10 V d.c. bias, ... -
Morphology and optical properties of thin silica films containing bimetallic Ag/Au nanoparticles
(2008)We have studied the optical spectra in the UV and visible regions, the morphology by scanning electron microscopy (SEM), and the X-ray photoelectron spectra (XPS) of bimetallic Ag/Au nanoparticles incorporated into transparent ... -
Photopatterning of PMMA films with gold nanoparticles: diffusion of AuCl4-ions
(2010)Photopatterning of poly(methyl methacrylate) (PMMA) films is performed by UV irradiation of the polymer films containing uniformly distributed AuCl 4 - ions. The process reduces the gold ions and leads to production of Au ... -
Time-resolved XPS analysis of the SiO2/Si system in the millisecond range
(2004)By applying voltage pulses to the sample rod while recording the spectrum, we show, for the first time, that it is possible to obtain a time-resolved XPS spectrum in the millisecond range. The Si 2p spectrum of a silicon ... -
X-ray photoelectron spectroscopy for resistance-capacitance measurements of surface structures
(AIP Publishing, 2005-04-29)In x-ray photoemission measurements, differential charging causes the measured binding energy difference between the Si 2p of the oxide and the silicon substrate to vary nonlinearly as a function of the applied external ... -
X-ray-induced production of gold nanoparticles on a SiO2/Si system and in a poly(methyl methacrylate) matrix
(American Chemical Society, 2005)Prolonged exposure to X-rays of HAuCl4 deposited from an aqueous solution onto a SiO2/Si substrate or into a poly(methyl methacrylate) (PMMA) matrix induces reduction of the Au3+ ions to Au0 and subsequent nucleation to ... -
XPS analysis with external bias: a simple method for probing differential charging
(John Wiley & Sons Ltd., 2004)The XPS spectra of thermally grown oxide layers on Si, Al, W and Hf substrates have been recorded while the samples were subjected to external d.c. voltage bias. The bias induces additional shifts in the measured binding ... -
XPS measurements for probing dynamics of charging
(Elsevier, 2010)The technique of recording X-ray photoemission data while the sample rod is subjected to ±10.0 V (dc) or square-wave pulses (ac) with varying frequencies in the range of 10-3 to 103 Hz for probing charging/discharging ...
