Single conductor magnetoresistance random access memory cell

Abstract

The single conductor magnetoresistance random access memory consists of memory cells which are made up of a flat thin film conductor, covered on both flat surfaces with thin magnetic films. Their coercive forces have different values. A current flowing through the conductor produces a magnetic field which circles the conductor. For high currents, which lead to magnetic fields larger than the coercive force of each of the magnetic films, the two magnetic films will be magnetized antiparallel to each other. Current values which produce magnetic fields between the values of the coercive field values of both films, will only modify the magnetization direction of the film with the low coercive field. It can be lined up parallel- or anti-parallel to the magnetization of the high coercive force film without changing the magnetization direction of the high coercive film. For materials which show the giant magnetoresistance effect, the resistance of the conducting film for parallel line-up of the magnetoresistance direction will differ noticeably from the resistance for a antiparallel line-up. Currents so low that the magnetic field generated around the conducting film is below the coercive fields will not change the magnetization direction even in the film with the low coercive field. Such a current can be used to measure the resistance of the memory element without destroying the information. It leads to a non-destructive read out.

Dependencies are inferred from the claim text.