The magnetic field sensitive MOSFET (MAGFET) is used as a sensor to convert the
magnetic field applied perpendicular to the channel to an electrical signal, like
current, voltage, or frequency [143]. Integrated magnetic field
sensor arrays can detect variations of the magnetic field in a small area.
Such sensor arrays are used, e.g., to determine fringing fields in electrical
motors or to detect defaults in metallic pipes [144]. Magnetic
sensor arrays have been fabricated up to sizes of about
and are also used to detect non-magnetic quantities like currents by their
surrounding magnetic field, displacement of magnets, or the movement of
membranes to which magnetic dipoles have been applied [145]. Thus,
two different applications can be distinguished: