The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This work describes the design and realization of a new low-cost instrument for real time measurement of blood flow, especially developed for dialysis machine monitoring. The instrument is realized by means of a self-mixing interferometer and a dedicated data elaboration system.
1D and 2D detector arrays have been realized on 270 μm thick 10 × 10 mm2 CVD diamond samples. The relatively high resistivity of diamond specimens in the dark (>3 × 1012 Ωcm) allowed the fabrication of photoconductive “sandwich” pixel-detectors. For both the structures, a semitransparent light-receiving back-side contact was used for detector biasing. Cross-talk between pixels was limited by using...
Different contact structures were studied to realize CVD-diamond sensors able to detect light beam displacements. Photons irradiate the sample backside where a mesh contact is used for device biasing. Photogenerated carriers are collected at the top-side where metal strip lines are realized. Depending on the layout of such contacts, beam displacement is measured by means of the elaboration of acquired...
Opaque-gate ultraviolet sensitive transistors were fabricated on H-terminated polycrystalline diamond. Butterfly shaped structures with different geometric ratios were realized. Observed trends with the gate unbiased demonstrated behavior as p-channel normally-off transistors, switched-on by the impinging UV light. Linearity with the UV beam power was also observed with over-gap radiation. Under steady...
In this paper the realization and the characterization of a new kind of resonant cavity enhanced photodetector (RCE), fully compatible with silicon microelectronic technologies and working at 1.55 μm, are reported.
In this paper we present a test chip in standard CMOS 0.35 um with different photovoltaic structures. In particular we realized several integrated micro solar cell to characterize an harvesting supply system thus to implement a power efficiency optimization technique based on the active area geometry. The photodiodes can be used as stand alone supply solar cells as well as an integrated harvester...
By now, fiber Bragg gratings (FBGs) represent a well assessed technology in sensing field. Unfortunately, to make FBGs sensitive to surrounding refractive index, hosting fiber structuring is needed. In last years, also tilted FBGs (TFBGs) have been proposed as promising technological platform for sensing applications. However, complex spectral features limit the practical exploitation of this technology...
A plastic biochip was developed for the detection of C reactive protein (CRP) and procalcitonin (PCT). It consists of a polymethylmethacrylate (PMMA) chip shaped in order to achieve several flow microchannels. Sandwich assays using the appropriate monoclonal antibodies were implemented with the capture antibody immobilized on the PMMA surface and the target antibody labelled with a fluorophore. A...
Long Period fiber Gratings (LPGs) fabricated by electrical discharge have found large interest as emerging devices in the field of optical communications and optical fiber sensors. Besides, the integration of UV LPGs with noble metal nano-layers, such as Au or Ag, seem to act as a promising sensing platform partly due to their potential applications for chemical and biological sensing. This work,...
Planar Al/GaN/Ni Schottky diodes were realized on GaN films deposited on sapphire substrates and characterized in the dark and under illumination. The optoelectronic characteristics of GaN photodetectors appear largely influenced by structural defects and impurities, which are clearly detected in photocurrent yield measurements. In particular, an exponential increase of the photocurrent is observed...
Toward the complete integration of color sensors in CMOS technologies, a novel color sensitive device, the Transverse Field Detector, is proposed. The TFD color detection principle is based on the creation of a transverse, V-shaped electric field configuration in a Silicon active layer. The electric field is generated only by means of surface biasing/ collecting electrodes. Taking advantage on the...
Fully-porous pn junctions were fabricated, by anodization of p/n substrates, and electrically tested. Process parameters, current density and illumination, were chosen to take into account the different morphological and mechanical characteristics of porous silicon layers resulting from anodization of the p- and n-type silicon. I–V curves were measured as a function of the aging time. Interestingly,...
Near-Infrared (NIR) picosecond pulsed light shined in biological tissues offers the opportunity for non-invasive imaging. We aimed at developing a winning photodetector electronics pairing for a broad field of multiple-wavelengths faint-signal optical investigations, like functional brain imaging. We present an electronic instrumentation based on silicon Single-Photon Avalanche Diode (SPAD) and fast-gating...
InGaAs/InP devices suitable as Single-Photon Avalanche Diodes (SPADs) for photon counting and photon timing applications in the near-infrared provide good detection efficiency and low time jitter, together with fairly low dark-count rate at moderately low temperatures. However, their performance is still severely limited by the afterpulsing effect, caused by carriers trapped into deep levels during...
High vacuum evaporation (VE) is used for the first time to grow thin films of novel tetraphosphonate, Tiiii[H, CH3, Ph], and tetrathiophosphonate, TSiiii[H, CH3, Ph], cavitands for gas sensing applications. The sensing capabilities of the samples were investigated by exposing Tiiii- and TSiiii-coated QCMs to very low concentrations of ethyl alcohol. The sensitivity, the speed (t50 = 5 s for both the...
The expected wide diffusion of hydrogen in the near future as clean fuel for PEM fuel cells and the potential danger of explosion consequent to the mixing of hydrogen with air, demands the introduction of reliable, robust and low cost hydrogen sensors. Titanium dioxide is a well known sensitive material for hydrogen sensors and the use of suitable titania nanostructures could be an efficient ways...
ZnO nanocrystals were prepared by a wet chemical method based on alkaline-activated 10 hydrolysis and condensation of zinc acetate solutions. With this procedure, the mean crystallite size of the obtained powders was found in the range from 2.5 to 4.5 nm. Drop casting of the nanocrystals onto alumina substrates allowed the fabrication of gas sensing devices. These Q-ZnO based gas sensors were tested...
New breakthroughs in preparation technology have given further impulse for developing chemical sensing devices based on nanostructured ZnO. Due to their peculiar characteristics and size effects, these materials often show novel physical properties. In this work, we studied the optical properties of ZnO nanowires, synthesized via evaporation-condensation (EC) process, by room temperature photoluminescence...
A Zn(II) porphyrin-porphyrin conjugated has been used as an optical transducer for the development of an optical sensor for diamines. The sensing molecule was immobilised on controlled pore glass (CPG) which was characterised with an appropriate flow cell connected to an optical spectrometer.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.