Grenoble Institute of Technology

About: Grenoble Institute of Technology is a education organization based out in Grenoble, France. It is known for research contribution in the topics: Hyperspectral imaging & Geology. The organization has 3427 authors who have published 5345 publications receiving 137158 citations. The organization is also known as: Grenoble INP.

Fabrication of SiC nanopillars by inductively coupled SF6/O2 plasma etching

Abstract: In this paper, we demonstrate a top-down fabrication technique for nanometre scale silicon carbide (SiC) pillars using inductively coupled plasma etching. A set of experiments in SF6-based plasma was carried out in order to realize high aspect ratio SiC nanopillars. The etched SiC nanopillars using a small circular mask pattern (115 nm diameter) show high aspect ratio (7.4) with a height of 2.2 µm at an optimum bias voltage (300 V) and pressure (6 mTorr). Under the optimal etching conditions using a large circular mask pattern with 370 nm diameter, the obtained SiC nanopillars exhibit high anisotropy features (6.4) with a large etch depth (>7 µm). The etch characteristic of the SiC nanopillars under these conditions shows a high etch rate (550 nm min−1) and a high selectivity (over 60 for Ni). We also studied the etch profile of the SiC nanopillars and mask evolution over the etching time. As the mask pattern size shrinks in nanoscale, vertical and lateral mask erosion plays a crucial role in the etch profile of the SiC nanopillars. Long etching process makes the pillars appear with a hexagonal shape, coming from the crystallographic structure of α-SiC. It is found that the feature of pillars depends not only on the etching process parameters, but also on the crystallographic structure of the SiC phase.

Tests of a Particle Flow Algorithm with CALICE test beam data

Abstract: The studies presented in this paper provide a first experimental test of the Particle Flow Algorithm (PFA) concept using data recorded in high granularity calorimeters. Pairs of overlaid pion showers from CALICE 2007 test beam data are reconstructed by the PandoraPFA program developed to implement PFA for a future lepton collider. Recovery of a neutral hadron's energy in the vicinity of a charged hadron is studied. The impact of the two overlapping hadron showers on energy resolution is investigated. The dependence of the confusion error on the distance between a 10 GeV neutral hadron and a charged pion is derived for pion energies of 10 and 30 GeV which are representative of a 100 GeV jet. The comparison of these test beam data results with Monte Carlo simulation is done for various hadron shower models within the GEANT4 framework. The results for simulated particles and for beam data are in good agreement thereby providing support for previous simulation studies of the power of Particle Flow Calorimetry at a future lepton collider.

Aqueous processing of paper separators by filtration dewatering: towards Li-ion paper batteries

Abstract: Despite the high number of research articles regarding the development of new high performance electrolytes for Li-ion batteries, relatively little work has been carried out for the investigation of green, mechanically robust, safe and commercially applicable paper separators. In this work, newly elaborated paper separators made of natural cellulose fibres are prepared by filtration dewatering. Paper separators show high porosity, wettability and mechanical robustness along with remarkable ion transport characteristics. The novel approach is conceptually validated by constant current charge/discharge cycling in a lab-scale Li-ion all-paper “pouch” cell assembled with a four-layer handsheet stacking separator in combination with a graphite-based paper-anode and a LiFePO4-based paper-cathode. This unravels the possibility of implementing the newly elaborated paper separators in safe, green and cost effective energy storage devices especially as they are obtained by rapid, low-cost and eco-friendly water-based paper-making techniques.