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Sol-gel derived multi-layer ZnO films were prepared by spin coating technique on soda-lime glass, silica, silicon and platinum substrates from an alcoholic solution of zinc acetate dihydrate and monoethanolamine at different synthetic conditions. The curing and annealing conditions for the ZnO films were adjusted based on the study performed on the ZnO xerogel powders. Structural and morphological features as well as the thermal behavior of the samples were investigated by complementary techniques including electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric and differential thermal analyses, and X-ray diffraction analysis. According to the electrical measurements performed on ZnO thin films sandwiched between Pt/Ti/SiO 2 substrate and Ag dishes as a top electrode, the selected fabrication conditions were suitable for fulfilling the requirements of active resistive layers for the development of memristive devices.

We report an optofluidic ring resonator sensor based on liquid-core hybrid silicon-polymer waveguides. The device features a planar layout that combines optical and fluidic functions on the same platform. A high quality factor of $1.44\, \times \, 10^{4}$ is achieved. The device resonant wavelength shift has been measured as a function of the water-core temperature, obtaining a temperature sensitivity of 0.0633 nm/°C. Based on the thermo-optic effect of water, this corresponds to a bulk refractive index (RI) sensitivity of $\sim 700$ nm per RI unit (RIU), resulting in the RI limit of detection of $\sim 1.57\times 10^{\mathrm {-6}}$ RIU. The planar architecture combined with an optofluidic design concept holds the promise of high functionality and compactness toward a complete on-chip integrated sensing system.

This work reports the development and the characterization of a microthermoelectric generator (μTEG) based on planar technology using electrochemically deposited constantan and copper thermocouples on a micro machined silicon substrate with a SiO2/Si3N4/SiO2 thermally insulating membrane to create a thermal gradient. The μTEG has been designed and optimized by finite element simulation in order to exploit the different thermal conductivity of silicon and membrane in order to obtain the maximum temperature difference on the planar surface between the hot and cold junctions of the thermocouples. The temperature difference was dependent on the nitrogen (N2) flow velocity applied to the upper part of the device. The fabricated thermoelectric generator presented maximum output voltage and power of 118 mV/cm2 and of 1.1 μW/cm2, respectively, for a device with 180 thermocouples, 3 kΩ of internal resistance, and under a N2 flow velocity of 6 m/s. The maximum efficiency (performance) was 2 × 10−3 μW/cm2 K2.

This paper presents the design, fabrication and evaluation of the new version of POSFET (Piezoelectric Oxide Semiconductor Field Effect Transistor) touch sensing device based tactile sensing chip. Implemented using CMOS (Complementary Metal Oxide Semiconductor) technology, the chip consists of POSFET device and the integrated bias and signal conditioning circuitry. In particular, a high compliance current sink and an output buffer have been integrated to respectively bias the POSFET device and to decouple the sensor from chip output. The performance of tactile sensing chip has been evaluated in the dynamic contact forces range of 0.01–3 N and the sensitivity of POSFET devices (without amplification) is 102.4 mV/N.

Micro/nanostructures of single-crystal Si, in the form of wires and ribbons, are promising building blocks for realizing high performance nano- to macro scale field-effect transistors (FETs). This work presents the method to fabricate single-crystal Si wires and ribbons from silicon-on-insulator (SOI) wafers using ''top-down'' fabrication strategy and transfer the same to ultra flexible substrates. Si wires with lengths ranging from 30 to 5000@mm and widths ranging from 4 to 50@mm have been fabricated. The parallel aligned wires are then successfully transferred, first to a flexible transfer substrates (PDMS) and then to the final receiver substrate (polyimide). Finally, the bending of Si wires has been investigated by bending them up to 220 degrees without breaking. Such a high bending of wires demonstrate the possibility of obtaining ultra flexible integrated electronics on flexible substrates.

This work presents an improved platform for single-site electroporation and controlled transfectants delivery. The device consists of a gold microelectrode array (MEA) with integrated microfluidics and nanostructured titanium dioxide (ns-TiO2) functionalized electrodes for the improvement of cell adhesion. Human cervical cancer cells (HeLa) have been successfully cultivated on chip surface using traditional protocols. The system has been previously tested by electroporating HeLa cells with Lucifer Yellow (LY) and then, in order to validate the approach and cell viability, with plasmid for the enhanced expression of Green Fluorescence Protein (pEGFP-N1) delivered through microchannels.

This work presents fabrication and evaluation of novel POSFET (Piezoelectric Oxide Semiconductor Field Effect Transistor) devices based tactile sensing chip. In the newer version presented here, the tactile sensing chip has been fabricated using CMOS (Complementary Metal Oxide Semiconductor) technology. The chip consists of 4 x 4 POSFET touch sensing devices (or taxels) and both, the individual taxels and the array are designed to match spatio–temporal performance of the human fingertips. To detect contact events, the taxels utilize the contact forces induced change in the polarization level of piezoelectric polymer (and hence change in the induced channel current of MOS). The POSFET device on the chip have linear response in the tested dynamic contact forces range of 0.01–3N and the sensitivity (without amplification) is 102.4mV/N.

In this study, we present a microdevice coated with titanium dioxide for cells and particles separation and handling. The microsystem consists of a pair of planar interdigitated gold micro-electrode arrays on a quartz substrate able to generate a traveling electric completed with a microfabricated three-dimensional glass structure for cell confinement. Dielectrophoretic forces were exploited for both vertical and lateral cell motions. In order to provide a biocompatible passivation layer to the electrodes a highly biocompatible nanostructured titanium dioxide film was deposited by supersonic cluster beam deposition (SCBD) on the electrode array. The dielectrophoretic effects of the chip were initially tested using polystyrene beads. To test the biocompatibility and capability of dielectrophoretic cell movement of the device, four cell lines (NIH3T3, SH-SY5Y, MDCK, and PC12) were used. Separation of beads from SH-SY5Y cells was also obtained.

This work presents the design, fabrication and characterization of a Si-based microseparation module for liquid chromatography (LC), targeted for agrofood applications and in particular for wine quality monitoring. The microsystem chip is a Silicon/Pyrex structure realized by anodic bonding. The basic Si-chip modules are an open tubular microcolumn with inlet/outlet for fluidic connections, a platinum heater and a Pt three-electrode amperometric sensor. Analytical calculations and finite element analysis have been performed to optimize the microcolumn design. Microchannels and inlet/outlet have been fabricated by deep reactive ion etching (DRIE) and tetra methyl ammonium hydroxide (TMAH) wet etching, respectively. The column has been functionalized with n-octyltriethoxysilane (C8-TEOS). Preliminary characterization tests of the microcolumn have been performed by evaluating the capability of the system to retain test solutions of acetic acid.

This work presents the realization of a Si-based miniaturised device for liquid chromatography (LC), targeted for agrofood applications and in particular for wine quality monitoring. The main modules of the system are: (1) a Si-based separation column, functionalized by n-octyltriethoxysilane (C8-TEOS), with inlet/outlet for fluidic connections; (2) a three-microelectrode voltammetric sensor. The system has been properly packaged and the capability of the sensing module to detect acetic acid concentration changes has been verified.

In this paper, we present a new type of rf MEMS switch with low actuation voltage and high isolation, for high rf power and reliability applications in telecommunication. ‘Symmetric toggle switch’ (STS) is based on push–pull mechanism and utilizes torsion springs and levers, placed symmetrically and transverse to CPW line. The switches designed for 8–14 GHz applications have analytically calculated and FEM simulated actuation voltages in the range of 8–10 V. The simulated insertion loss and isolation for the devices are 0.25 and 35 dB, respectively, at 10 GHz. The fabrication process and preliminary experimental results are also presented.

This work focuses on the realization of three different micro-actuators that will be integrated in a lab-on-chip for bioaffinity assays. The aim is to create a microfluidic network to control the sample and reagent delivery as well as the washing cycles for a complete analysis. The three micropumps have different working principles (electromagnetic, electrolytic and peristaltic actuation methods), but they share the same fabrication process. The reason for adopting three different actuation modes is mainly related to the different functionalities that have to be managed at microfluidic level. In particular the electrolytic one-shot micropump will be used for sample and reagents delivery, while the peristaltic and the electromagnetic micropumps are both good candidates for the washing cycles.

The present work is aimed at the design and fabrication of microfluidic devices for pharmacological in-vitro tests on cells as a tool for individuating the concentration range in which the drug effectiveness is guaranteed, with particular attention to anti-osteoporotic therapies with strontium ranelate. The microsystem consists of a microchannels network for the delivery and mixing of chemical species, designed to provide a controlled drug concentration to each cell culture [1]. The design and the optimization of the microfluidic network were carried out by means of both analytical and computational approaches. Besides, micromixers and wells modules were modeled, fabricated and tested separately. A prototype of the complete device has been produced and further experimental tests will be performed.