Closed-flux elements for integrated magnetic memories

A description of the design and technology of batch-fabricated core-like memory elements is presented. A bottom FeSi and a top NiFe layer form a closed-flux path encircling two mutually insulated conductor layers. All layers are deposited on a silicon chip and structured by photolithographic techniques. The compatibility with integrated circuits is pointed out. Element densities may be as high as 20 000/cm². Due to the small dimensions, currents are below 50 mA with a switching time of about 100 ns. The output voltage is between 5 and 10 mV.