Micromagnetic studies of read and write process in magnetoresistive random access memory

A micromagnetic model is established to analyze the read and write processes in a magnetoresistance random access memories (MRAM) cell. The magnetoresistive curves of NiFeCo/interlayer/NiFeCo cells are analyzed and compared with available experiments. The switching fields of the two magnetic layers A and B in a MRAM cell are studied versus different geometrical parameters of a cell. The word current I-w(A) and I-w(B) corresponding, respectively, to the switching of films A and B, and the related error of I-w(A) and I-w(B) under a given sense current I-s, are analyzed and compared with experiment. In a cell with a given width W, proper geometrical parameters such as the thickness of the magnetic layers and the aspect ratio (length over width) are found based on the analysis of the I-w(A)-I-s and I-w(B)-I-s curves. (C) 2000 American Institute of Physics. [S0021-8979(00)07805-1].