Multilayer structure and sensor and fabrication process

摘要

A novel multilayer magnetic structure comprises a stack of alternate layers which are (a) first layers (6, 16) based on magnetic material; (b) second layers (12) of Ag or Ag-rich alloy; and (c) thin interfacial layers (8, 14) of Co or Co-rich alloy located at the interfaces of the first and second layers. Preferably, the magnetic material has the formula (I) Ni100-x-y-zCoxFeyAz (I) (where x is 0-100, y is 0-100, z is 0-40 and x+y+z is 0-100), e.g. a 'Permalloy' (RTM). Also claimed are (i) a process for forming the above structure; (ii) a magnetoresistive effect multilayer transducer comprising the above structure; (iii) a current sensor for measuring current passing through an electrical conductor, the sensor having a magnetoresistive strip of the above structure surrounding the conductor with the strip ends being connected to a current measuring device; and (iv) a magnetic read and/or write head having a magnetoresistive element of the above structure.