スピンバルブ膜を用いたメモリー素子

Abstract

A new type of magnetoresistive memory was developed, using spin-valve multilayers composed of semi-hard magnetic layers and soft magnetic layers, separated by nonmagnetic layers. The fabricated memory element is composed of a word line of Au film and a magnetoresistive sense line of [ {CoPt / Cu / NiFeCo / Cu}]n multilayers and [NiFe/Cu/Co] sandwiches. In the [{CoPt/Cu/NiFeCo/Cu}]n multilayers, it was possible to read out from memory written to by applying an external field, however, it was impossible to write by applying a field with the word line, owing to the large size of the writing field. In [NiFe/Cu/Co] sandwiched film, a relatively small writing field made it possible to write to a memory and to read out from it. This spin-valve memory has non-volatile and non-destructive read-out properties.