Speaker
Ivan Duran
(Tokamak)
Description
Hall sensors with their small dimensions, simple principle of operation, and large dynamic range offer an attractive non-inductive method of magnetic field measurements for future fusion reactors operating in steady state regime. The applicability of commercially available Hall sensors, which are based on semiconductor sensing layer, is strongly limited by insufficient range of operational temperatures and limited radiation hardness. Hall sensors with metallic sensing layer offer interesting alternative compared to the semiconductor devices. Due to their very low sensitivity, the metal-based sensors are practically omitted in both commercial and research spheres. On the other hand, their expected advantages such as higher radiation hardness and high temperature resistance can possibly prevail over this weakness in case of their application in future fusion based power generating systems.
Recently, the Hall sensors based on bismuth sensitive layer were selected to be implemented on ITER as ex-vessel steady state magnetic sensors. The proposed contribution will review the present optimized design of these sensors and their manufacturing technology, including some alternative options. The sensor prototypes were extensively tested to evaluate their compatibility with ITER requirements. Characterisation of the sensors properties was done using AC detection technique to ensure high noise immunity. The measured quantities include: offset voltage, sensitivity and its dependence on temperature, input and output resistance, linearity, charge carrier density and mobility, as well as performance of the sensor after temperature cycling and neutron irradiation up to the 101919 cm-2-2.
Co-authors
George Vayakis
(ITER Organization, Route de Vinon-sur-Verdon, 13076 St. Paul-lez-Durance, France)
Ivan Duran
(Tokamak, Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 182 00 Praha 8, Czech Republic)
Ladislav Viererbl
(Research Centre Rez, Hlavní 130, 250 68 Husinec-Řež, Czech Republic)
Martin Kocan
(ITER Organization, Route de Vinon-sur-Verdon, 13076 St. Paul-lez-Durance, France)
Michal Kohout
(Institute of Physics of the CAS, Na Slovance 1992/2, 182 21 Praha 8, Czech Republic)
Radomir Musalek
(Tokamak, Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 182 00 Praha 8, Czech Republic)
Slavomir Entler
(Tokamak, Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 182 00 Praha 8, Czech Republic)
Tomas Chraska
(Tokamak, Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 182 00 Praha 8, Czech Republic)
