This article addresses the method of sensing mechanical quantities, in particular force and pressure, without the electrical connection of the sensing element and the electronics. The information about the mechanical quantity is transmitted only by evaluating the changes in the electromagnetic field created around the sensor. The sensor is designed on the basis of a flexible micro-electro-mechanical element (MEMS), the resonance of which carries the information about the measured quantity.

This paper deals with the performance of the AR-N7520 (Allresist) negative electron beam resist (EB resist) which was selected as an etch mask for the fabrication of gratings on GaAs substrates. The developed resist sidewall shape is crucial for this purpose. The required near-to-vertical sidewall shape can be achieved by optimizing the electron beam lithography (EBL) process based on experimental investigations and computer simulations. The sidewall shape dependence on the EBL parameters (exposure dose, resist pattern, etc.) and the proximity effect are studied.

Force measurement is a science discipline that experiences significant progress with the introduction of new materials and evaluation methods. Many different sensor types, working on different principles, have been developed and reviewed and have found use in medicine as well as many other industries. New trends and demands require a size reduction and simple applicability, with the use of, for example, micro electromechanical systems (MEMS). For purposes of this study, the initial MEMS body is supplemented by its scaled version. Force measurement in this study works on the force to time-delay conversion principle. A compact compliant mechanical body (CCMB) with an embedded parallel resonant circuit (PRC) acting as a transducer realizes the conversion. Depending on the resonant frequency of the transducer (CCMB or MEMS), we have measured the applied force based on the reverse influence of the transducer on the surrounding EM field. The analysis shows that the transducer’s resonant frequency has a detectable reverse influence on the voltage-controlled oscillator (VCO) DC supply current. The force influencing the transducer is determined by the DC supply current ripple position during the VCO frequency sweep. The study presents the method proposal and mathematical analysis, as well as its function verification by simulation and prototype measurements. The proposed principle was validated on a CCMB prototype capable of measuring forces up to ∼2.5 N at a sampling frequency of ∼23 kHz, while the measured time-delay ranges from 14.5 µs to 27.4 µs.

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This work presents the applications of the method of the disappearing diffraction pattern for refractometric measurements and analysis of scattering media. The behavior of the refractive indices of different aqueous dispersions containing metal and polymer particles is studied theoretically and experimentally. Both metallic and latex solutions exhibit linear dependence of the refractive index on the concentration of particles. Values of the specific refractive index increment dn Idc for Co, Fe and Ag nano-dispersions are calculated. Poly(2-ethylhexyl) acrylate and poly(vinyl acetate) latexes with size of particles between 50 and 1300 urn and concentration up to the maximum possible are systematically studied with respect to the properties of the particles -concentration, diameter and refractive index. Empirical relationships are derived for the investigated latexes, describing the dependence of the refractive index of latexes on their properties and on the light wavelength. Such approach could be used to solve the inverse problem of calculating the concentration or the size ofparticles, measuring the refractive index. It is shown that the refractometry provides a simple, easy and accurate way to study and analyze properties of dense nano-and micro-dispersions.

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In this article we describe the electron-beam direct-write (EBDW) lithography process for the AZ 5214E photoresist which is, besides its sensitivity to UV radiation, sensitive also to electrons. An adapted process flow is provided. At the same time we examine the resistance of this resist to RIE and its suitability as an etch-mask for etching thin Ag layers in N 2 plasma. A comparison with several chosen resists (PMMA, ma-2405, ma-N 1402, SU-8 2000 is provided.K e y w o r d s: AZ 5214E resist,

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