GERENCIA FÍSICA

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https://nuclea.cnea.gob.ar/handle/20.500.12553/5207

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Examinando GERENCIA FÍSICA por Autor "Alcalde Bessia, F."

Mostrando 1 - 4 de 4
  • Miniatura
    ÍtemAcceso Abierto
    Displacement Damage in CMOS Image Sensors After Thermal Neutron Irradiation
    (IEEE, 2018-10-05) Alcalde Bessia, F.; Pérez, M.; Sofo Haro, M.; Sidelnik, I.; Blostein, J.J.; Suárez, S.; Pérez, P.; Gómez Berisso, M.; Lipovetzky, J.; Gerencia Física. Departamento Materia Condensada. División Bajas Temperaturas
    In this paper, CMOS image sensors were exposed to thermal neutrons observing an increase in the dark signal of many pixels. The effect was found to be similar to the damage caused by alpha particles irradiation. Rutherford backscattering spectroscopy (RBS) and SIMNRA simulation were used to confirm that the sensors contain boron in the insulation layers. The damage produced by thermal neutrons is explained as displacement damage caused by alpha particles and lithium-7 ions in the silicon active volume of the sensors after boron-10 thermal neutron capture.
  • Miniatura
    ÍtemAcceso Abierto
    Fully-Depleted SOI MOSFET Sensors in Accumulation Mode for Total Dose Measurement
    (IEEE (Institute of Electrical and Electronics Engineers), 2018-00-00) Alcalde Bessia, F.; Flandre, D.; André, N.; Irazoqui, J.; Pérez, M.; Gómez Berisso, M.; Lipovetzky, J.; Gerencia Física. Departamento Materia Condensada. División Bajas Temperaturas
    Fully Depleted Silicon-on-Insulator (FD-SOI) transistors fabricated with a custom process in Université Catholique de Louvain (UCL) were irradiated with X-rays using an Elekta Synergy radiotherapy linear accelerator. I-V curves of FD-SOI are sensitive to charges produced in the buried oxide (BOX) by ionizing radiation, so it is possible to use these devices as radiation dosimeters. In this work, we evaluated the use of thick BOX back-gate transistors for Total Ionizing Dose (TID) measurement using different bias conditions and we obtained a maximum sensitivity of 191 mV/Gy for devices operating in accumulation mode.
  • Miniatura
    ÍtemAcceso Abierto
    Soft X-rays spectroscopy with a commercial CMOS image sensor at room temperature
    (Elsevier, 2020-02-00) Sofo Haro, M.; Alcalde Bessia, F.; Pérez, M.; Blostein, J.J.; Balmaceda, D.F.; Gómez Berisso, M.; Lipovetzky, J.; Gerencia Física. Departamento Materia Condensada. División Bajas Temperaturas
    Besides their application in point and shoot cameras, webcams, and cell phones, it has been shown that CMOS image sensors (CIS) can be used for dosimetry, X-ray and neutron imaging applications. In this work we will discuss the application of an ON Semiconductor MT9M001 CIS, in low energy X-ray spectroscopy. The device is a monochromatic front-side illuminated sensor, very popular in consumer electronics. In this work we introduce the configuration selected for the mentioned sensor, the image processing techniques and event selection criteria, implemented in order to measure the X-ray energy in the range from 1 to 10 keV. Several fluorescence lines of different samples have been resolved, and for first time the line resolution have been measured and analyzed. We achieved a FWHM of 232 eV at 6.4 keV, and we concluded that incomplete charge collection (ICC) of the charge produced by the X-ray contributes to the resolution, being this effect more important at higher X-ray energies. The results analyzed in this work indicate that the mentioned CIS are specially suitable for X-ray applications in which energy and spatial resolutions are simultaneously required.
  • Miniatura
    ÍtemAcceso Abierto
    Ultra Low Power Ionizing Dose Sensor Based on Complementary Fully Depleted MOS Transistors for Radiotherapy Application
    (IEEE, 2019-10-02) Alcalde Bessia, F.; Flandre, D.; André, N.; Irazoqui, J.; Pérez, M.; Gómez Berisso, M.; Lipovetzky, J.; Gerencia Física. Departamento Materia Condensada. División Bajas Temperaturas
    We evaluate the use of thick buried oxide (BOX) of fully depleted silicon-on-insulator (FD-SOI) transistors for total ionizing dose (TID) measurements in a radiotherapy application. The devices were fabricated by a custom process at Université Catholique de Leuven (UCL) that allows one to make accumulation mode pMOS transistors and inversion mode nMOS transistors. We characterized the temperature behavior of these devices and the response under X-ray irradiation produced by an Elekta radiotherapy linear accelerator and compared the obtained dose sensitivity with other published works. Taking advantage of these devices, an ultralow power MOS ionizing dose sensor or MOS dosimeter with inherent temperature compensation is presented. This dosimeter achieved a sensitivity of 154 mV/Gy with a temperature error factor of 13 mGy/°C and a current consumption below 1 nA.