MAGNETIC FIELD SENSOR

摘要

A magnetic field sensor comprising a layered structure (3) E/FO/S/F, in which: E is an exchange-biasing layer, comprising nickel oxide; FO is a ferromagnetic layer with a fixed magnetization comprising cobalt; S is a spacer layer; Ff is a ferromagnetic layer with a free magnetization, whereby the material of the layer Ff has a magnetostriction constant of at most 1.5 x 10<-6> and a crystal anisotropy of at most 1.3 J/m<3>. Such a structure (3) demonstrates a relatively high magneto-resistance ratio (of the order of 15 %), and yet a relatively low coercivity (of the order of 0.2 kA/m). Examples of suitable materials for use in the layer Ff include Ni66Fe16Co18 and Ni72Fe21Co7.