1,720,967 research outputs found
Status of the 3D Silicon Detectors activities at FBK
No full textIn the talk, ongoing activities on 3D processes will be presented. FBK is actively involved in the realization of detectors with RD53 and CROC designs for both ATLAS and CMS experiments. The latest developments and parametric measurements with Temporary Metal for these processes will be discussed. Additionally, FBK is continuing the development of 3D sensors based on trenches. Due to their geometry, these sensors are considered candidates for achieving excellent temporal resolutions along with high damage resistance. In the AIDA Innova project, FBK is producing a batch, and the main characteristics of this batch will be highlighted
How the Gas Flow Affects Conductometric Sensor Performance
No full textThe performance of a metal oxide gas sensor can be affected by different parameters as the fabrication process of the sensitive layer or the post-annealing treatment. [...
ZnO nanoneedles grown on chip for selective NO2 detection indoors
No full textA conductometric sensor based on ZnO nanoneedles for the detection of NO2 is described. The material is grown on chip over Pt interdigitated electrodes patterned on alumina substrates without the need of a catalyst layer. The nanostructure growth relies on two different mechanisms (Vapor-Solid and Liquid-Solid) so nanoneedles with few μm of length and wurtzite structure are obtained. The procedure is optimized on chip, which supposes a significant advantage in the fabrication of nanostructures on sensing devices. The sensor response has been measured under a target gas (NO2) and two interfering pollutants (benzene and formaldehyde). Lower working temperatures than other pure ZnO nanostructures found in the literature have been achieved and limit of detection (LOD) in the order of ppb has been reached. The significant higher response to NO2 with respect to benzene and formaldehyde makes this sensing device suitable for selective NO2 detection indoors
ZnO Thin Film Processed by Direct Laser Interference Patterning for Formaldehyde Detection
No full textDirect laser interference patterning (DLIP) is a fast nanostructuring technique able to generate periodic patterns in the submicrometric range, what modifies the morphology and structural properties of semiconductors. DLIP has been used on gas sensors based on ZnO thin film, generating 1D patterns. The nanostructuring has modified the crystal structure and the surface topography. DLIP acts similarly to a thermal treatment from the crystallographic point of view and has been used to detect low concentration of formaldehyde (HCHO). Comparable magnitude of responses (around the 25 % for 20 ppm of formaldehyde) are shown for sensors thermally treated sensors and sensors processed by DLIP
Influence of the test-chamber shape on the performance of conductometric gas sensors
Get PDFIn this article, CFD simulations results are presented as a key tool to the comprehension of the target gas concentration evolution in a test chamber, at different working conditions. The simulation results are compared with the experimental data, which shows a qualitative good correlation with the evolution of the concentration gradient detected. The experiments were carried out using an aluminum gas test chamber, where a WO3 based conductometric sensor is introduced. The results demonstrate how the response time is dependent on the sensor working conditions. Analyzing the CFD and experimental results, some assumptions for this behavior are proposed.
The WO3 sensor needs a Pt heating element, which is heated up to 300 °C. As the response is highly temperature-dependent, the temperature distribution on the sensor surface was measured by an IR thermographic camera. The simulation results show that the temperature distribution matches with those obtained experimentally. To validate the model, a mesh and time step convergence study was also implemented
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Laser Interferometry for Broad Area SPR-Grating Couplers in Chemical Applications
No full textIn this work, the fabrication of a SPR (Surface Plasmon Resonance)-grating coupler using Laser Interference Lithography (LIL) has been investigated, giving rise to large area diffraction gratings on a 100 nm-thick gold film. The period of the diffraction grating is Λ = 500 nm. The SPR sensor has been tested towards several liquids showing a maximum sensitivity of S = 390 nm/RIU
- …
