The role of electron electron double resonance in span relaxation studies on radicals in liquid solutions

Applied Science

Review of scaling effects on physical properties and practicalities of cantilever sensors

Reducing sensor dimension is a good way to increase system sensitivity and response. However the advantages gained must be weighed against other effects which also became significant during the scaling process. In this paper, the scaling effect of cantilever sensors from micrometre to nanometre regimes is reviewed. Changes in the physical properties such as Q-factor, Young's modulus, noise and nonlinear deflections, as well as effects on practical sensor applications such as sensor response and sensor readouts, are presented. Since cantilever is an elemental transducer and device building block, its scaling effects can be further extrapolated to other sensing systems and applications.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.BUS/Quantum DelftManagement SupportBio-Electronic

Influence of hydrogen silsesquioxane resist exposure temperature on ultrahigh resolution electron beam lithography

Performance of hydrogen silsesquioxane (HSQ) resist material with respect to the temperature during electron beam exposure was investigated. Electron beam exposure at elevated temperatures up to 90?°C shows sensitivity rise and slight contrast (?) degradation compared to lower temperature cases. Ultrahigh resolution structures formed at elevated temperatures manifest better uniformity together with aspect ratio improvement and less linewidth broadening with overdose. Potential mechanisms for observed phenomena are proposed.QN/Quantum NanoscienceApplied Science

High-dose exposure of silicon in electron beam lithography

Imaging Science and TechnologyApplied Science

Photonic crystal Mach-Zehnder interferometer operating in the self-collimation mode of light

Kavli Institute of NanoscienceApplied Science

Size-dependent effective Young’s modulus of silicon nitride cantilevers

The effective Young’s modulus of silicon nitride cantilevers is determined for thicknesses in the range of 20–684 nm by measuring resonance frequencies from thermal noise spectra. A significant deviation from the bulk value is observed for cantilevers thinner than 150 nm. To explain the observations we have compared the thickness dependence of the effective Young’s modulus for the first and second flexural resonance mode and measured the static curvature profiles of the cantilevers. We conclude that surface stress cannot explain the observed behavior. A surface elasticity model fits the experimental data consistently.Kavli Institute of NanoscienceApplied Science

Asymmetry reversal and waveguide modes in photonic crystal slabs

The measured reflection spectra of two-dimensional photonic crystal slabs consist of an asymmetric peak on top of an oscillating background. For p-polarized light, the asymmetry of the peak flips for angles of incidence beyond Brewster’s angle. We explain the observed line shapes with a Fano model that includes loss and use a waveguide model to predict the resonance frequencies of the photonic crystal slab. Finite-difference time domain calculations support the model and show that the resonance due to a higher order mode disappears when the substrate refractive index is increased beyond ns = 2.04. This is readily explained by the cut-off condition of the modes given by the waveguide model.NanofacilityApplied Science

Transmission measurement of the photonic band gap of GaN photonic crystal slabs

A high-contrast-ratio (30 dB) photonic band gap in the near-infrared transmission of hole-type GaN two-dimensional photonic crystals (PhCs) is reported. These crystals are deeply etched in a 650 nm thick GaN layer grown on sapphire. A comparison of the measured spectrum with finite difference time domain simulations gives quantitative agreement for the dielectric band and qualitative agreement for the air band. The particular behavior of the air band arises from the relatively low index contrast between the GaN layer and the sapphire substrate. Our results call for extension of the operation of GaN PhCs to the visible range.Kavli Institute of NanoscienceApplied Science