Magnetic tunneling junction devices for non-volatile random access memory

Abstract

Magnetic tunnel junctions (MTJs) are sandwiches of ferromagnetic (FM) layers separated by a thin insulating layers. Generally, MTJ devices have certain properties for optimal MRAM performance. This article discusses the required properties and demonstrates useful MTJ structures, sub-micron in size, with very high MR values at room temperature and small magnetic fields, and enhancement of these MR values on annealing at moderate temperatures. It also presents MTJs with resistance-area products which will allow scaling of MTJ MRAM to densities needed for gigabit memory chips.