Problem of the self-field of a hall probe and a microscope for its investigation

• The bias current through the Hall transducer gives rise to jumps in the induction at the edges of a thin epitaxial n -InSb film near the Hall contacts. • A setup is designed to determine the asymmetry of Hall contacts and to study the spatial distribution of the self-field of the current on the surface of and around the HT. • The 3D microscope proposed allows one to carry out 3D magnetic field scanning on the surface of the HT under study. • It is found that the higher the asymmetry of the Hall contacts, the more strongly the spatial characteristics of the HT are distorted. • Preliminary compensation of the self-field of the current allows one to increase the sensitivity of the magnetometer by more than an order of magnitude. To increase the spatial resolution of the magnetometer, one should place the HT as close as possible to the object under test. Attention is drawn to the effect of the self-field H HT of the bias current I HT through a Hall transducer (HT) on the objects of study and the measurement accuracy of the Hall magnetometer. The field H HT of an n -InSb– i- GaAs heteroepitaxial HT fabricated by growing a doped indium antimonide epitaxial film on a semi-insulating single-crystal i -GaAs substrate is considered. A setup is designed to study the spatial distribution of H HT on the surface of the HT and around it. It is found that magnetic induction jumps appear at the edges of a thin epitaxial n -InSb film near the Hall contacts of the HT due to the breaks in the force lines of the field H HT . For a nonuniform distribution of I HT over the cross section of the film, this gives rise to a voltage on the Hall contacts that is superimposed on the useful Hall signal, thus leading to an error.