An MRAM is disclosed that has a MTJ comprised of a ferromagnetic layer
with a magnetization direction along a first axis, a super-paramagnetic
(SP) free layer, and an insulating layer formed therebetween. The SP free
layer has a remnant magnetization that is substantially zero in the
absence of an external field, and in which magnetization is roughly
proportional to an external field until reaching a saturation value. In
one embodiment, a separate storage layer is formed above, below, or
adjacent to the MTJ and has uniaxial anisotropy with a magnetization
direction along its easy axis which parallels the first axis. In a second
embodiment, the storage layer is formed on a non-magnetic conducting
spacer layer within the MTJ and is patterned simultaneously with the MTJ.
The SP free layer may be multiple layers or laminated layers of CoFeB.
The storage layer may have a SyAP configuration and a laminated
structure.