Magnetic-field effect in MOS transistor with injecting source

Abstract

The I-V characteristics of a p+-n-p+ planar MOS transistor made by the standard technology under the regime of injecting p+-n source-substrate junction without and in the presence of an outer magnetic-field B, which deviates the carriers toward the Si-SiO 2 interface or in the opposite direction, were experimentally investigated. A control by B of the drain-source current IDS was observed. The current I DS and the control of its steepness through the gate bias considerably exceeded the values obtained in the absence of injection. This effect was explained with the increase of the part of the injected current-carriers from the channel at a growing gate bias and with the decrease of the effective distance source-drain. The magnetosensitivity can be connected with the hole current which is controlled by the magnetic-field and sharply increases with the drop of temperature

MOSFET dosimeter characterization in MR‐guided radiation therapy (MRgRT) Linac

“…The MOSFET measurements with the MR magnetic field turned On, in comparison to the Off condition, did not influence the MOSFET dose response; the dose response ratio was within ±2% for 100–600 MUs dose range, which is within the dosimeter reproducibility. The 0.345 T magnetic field of the MRIdian ® linac does not seem to affect MOSFET measurements, in agreement with results obtained by Lysenko et al for P‐type MOSFET threshold voltage, for magnetic fields up to 1.5 Tesla, and with no source–substrate bias. Thorpe et al reported no significant change in the MOSFET current voltage characteristics, I (V), with a magnetic field of 1 T, turned On or Off, at different setup configurations; hence, the MOSFET threshold voltage was deemed not affected by the magnetic field.…”

“…The magnetic field is known to affect semiconductor devices as in some conditions it deviates carriers toward the Si/SiO 2 interface, resulting in change of the magnetoresistance of the conduction channel. In our MOSFET measurements, the effect of the magnetic field on detector response was found to be negligible and within the detector reproducibility; this is likely related to the detector operation in the low drain current region at the low onset V th voltage, which makes the channel magnetoresistance and Hall effect negligible …”

“…As drawbacks, MOSFETs show a time dependence of the readout (fading), especially for very small doses (<1 cGy), and a relatively short life, that is, maximum cumulated dose. It is also known that the magnetic field affects semiconductor devices as in some conditions it deviates carriers toward the Si/SiO 2 interface, resulting in change of the magnetoresistance of the conduction channel. This effect is known as the Hall effect, as a small electric field is generated as a result of a magnetic field applied perpendicular to the direction of the drain current, resulting in change of the space charge at the MOSFET conduction channel …”

Bases physiques et performances des nouveaux (micro)capteurs magnétiques à semiconducteur

“…Signalons qu'il existe d'autres composants magné-Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/rphysap:0198400190206900 tosensibles à semiconducteur réalisables par des technologies « planar » usuelles mais basés sur d'autres principes (tels les magnétotransistors MOS [29,30] ou bipolaires, en fonctionnement normal [31][32][33] ou en régime d'avalanche [34,35], ainsi que les dispositifs à résistance négative [36]), qui ne seront pas analysés ici.…”