Gloria Kerszykowski

High density submicron magnetoresistive random access memory (invited)

Various giant magnetoresistance material structures were patterned and studied for their potential as memory elements. The preferred memory element, based on pseudo-spin valve structures, was designed with two magnetic stacks (NiFeCo/CoFe) of different thickness with Cu as an interlayer. The difference in thickness results in dissimilar switching fields due to the shape anisotropy at deep submicron dimensions. It was found that a lower switching current can be achieved when the bits have a word line that wraps around the bit 1.5 times. Submicron memory elements integrated with complementary metal–oxide–semiconductor (CMOS) transistors maintained their characteristics and no degradation to the CMOS devices was observed. Selectivity between memory elements in high-density arrays was demonstrated.

High density pseudo spin valve magnetoresistive RAM

Magnetoresistive RAM (MRAM), based on the integration of giant magnetoresistive material and Si ICs, is a nonvolatile memory technology which has unlimited read/write endurance. In this paper, nonvolatile memory cells based on pseudo spin valve giant magnetoresistive (GMR) material are demonstrated. Comparison of spin value GMR cells and pseudo spin valve cells is discussed. Functional testing of pseudo spin valve devices is presented.