Razvan Pascu1,2,3, Gheorghe Pristavu2, Gheorghe Brezeanu2, Florin Draghici2, Philippe Godignon4, Cosmin Romanitan1, Matei Serbanescu2, Adrian Tulbure5. 1. National Institute for Research and Development in Microtechnologies-IMT Bucharest, 126A, Erou Iancu Nicolae Street, 077190 Bucharest, Romania. 2. Faculty of Electronics, Telecommunications and Information Technology, University "Politehnica" of Bucharest, 060042 Bucharest, Romania. 3. Romanian Young Academy, Research Institute of the University of Bucharest, University of Bucharest, 030018 Bucharest, Romania. 4. Centre Nacional de Microelectrònica, CNM-CSIC, 08193 Barcelona, Spain. 5. Department of Informatics, Mathematics and Electronics, Faculty of Exact Sciences and Engineering, University "1 Decembrie 1918" of Alba Iulia, No. 5, Gabriel Bethlen Street, 510009 Alba Iulia, Romania.
Abstract
A SiC Schottky dual-diode temperature-sensing element, suitable for both complementary variation of VF with absolute temperature (CTAT) and differential proportional to absolute temperature (PTAT) sensors, is demonstrated over 60-700 K, currently the widest range reported. The structure's layout places the two identical diodes in close, symmetrical proximity. A stable and high-barrier Schottky contact based on Ni, annealed at 750 °C, is used. XRD analysis evinced the even distribution of Ni2Si over the entire Schottky contact area. Forward measurements in the 60-700 K range indicate nearly identical characteristics for the dual-diodes, with only minor inhomogeneity. Our parallel diode (p-diode) model is used to parameterize experimental curves and evaluate sensing performances over this far-reaching domain. High sensitivity, upwards of 2.32 mV/K, is obtained, with satisfactory linearity (R2 reaching 99.80%) for the CTAT sensor, even down to 60 K. The PTAT differential version boasts increased linearity, up to 99.95%. The lower sensitivity is, in this case, compensated by using a high-performing, low-cost readout circuit, leading to a peak 14.91 mV/K, without influencing linearity.
A SiC Schottky dun>an class="Chemical">al-diode temperature-sensing element, suitable for both complementary variation of VF with absolute temperature (CTAT) and differential proportional to absolute temperature (PTAT) sensors, is demonstrated over 60-700 K, currently the widest range reported. The structure's layout places the two identicaldiodes in close, symmetrical proximity. A stable and high-barrier Schottky contact based on Ni, annealed at 750 °C, is used. XRD analysis evinced the even distribution of Ni2Si over the entire Schottky contact area. Forward measurements in the 60-700 K range indicate nearly identical characteristics for the dual-diodes, with only minor inhomogeneity. Our parallel diode (p-diode) model is used to parameterize experimental curves and evaluate sensing performances over this far-reaching domain. High sensitivity, upwards of 2.32 mV/K, is obtained, with satisfactory linearity (R2 reaching 99.80%) for the CTAT sensor, even down to 60 K. The PTAT differential version boasts increased linearity, up to 99.95%. The lower sensitivity is, in this case, compensated by using a high-performing, low-cost readout circuit, leading to a peak 14.91 mV/K, without influencing linearity.
Entities:
Keywords:
SiC-Schottky diode; linearity; readout circuit; sensitivity; wide-range temperature sensor
Authors: Demetrio Iero; Massimo Merenda; Riccardo Carotenuto; Giovanni Pangallo; Sandro Rao; Gheorghe Brezeanu; Francesco G Della Corte Journal: Sensors (Basel) Date: 2021-04-29 Impact factor: 3.576