Magnetic memory with a thermally assisted writing procedure

A method for writing a magnetic memory device comprising a plurality of memory cells, each memory cell comprising a magnetic tunnel junction formed from a magnetic storage layer containing a ferromagnetic storage layer having a magnetization that can be reversed during the writing process, a reference layer having a magnetization being always substantially in the same direction during the writing process, and an insulating layer between the reference layer and the storage layer;

• the magnetic tunnel junction further comprising a writing layer made of a ferrimagnetic 3d-4f amorphous alloy comprising a net magnetization containing a first magnetization contribution originating from the sub-lattice of 3d transition elements and a second magnetization contribution originating from the sub-lattice of 4f rare-earth elements;
• the method comprising:
• orienting the net magnetization of the writing layer substantially antiparallel to the magnetization of the ferromagnetic storage layer;
• reversing the magnetization of the first magnetization contribution of the writing layer substantially antiparallel with the magnetization of the ferromagnetic layer;
• reversing the magnetization of the second magnetization contribution of the writing layer substantially antiparallel with the first magnetization contribution;
• and
• reversing the magnetization of the ferromagnetic storage layer substantially antiparallel in respect to the net magnetization of the writing layer.

A method for writing a magnetic memory device comprising a plurality of memory cells, each memory cell comprising a magnetic tunnel junction formed from a magnetic storage layer containing a ferromagnetic storage layer having a magnetization that can be reversed during the writing process, a reference layer having a magnetization being always substantially in the same direction during the writing process, and an insulating layer between the reference layer and the storage layer;

• the magnetic tunnel junction further comprising a writing layer made of a ferrimagnetic 3d-4f amorphous alloy comprising a net magnetization containing a first magnetization contribution originating from the sub-lattice of 3d transition elements and a second magnetization contribution originating from the sub-lattice of 4f rare-earth elements;
• the method comprising:
• an initial step where the net magnetization of the writing layer is oriented antiparallel in respect to the magnetization of the ferromagnetic storage layer due to magnetostatic interactions between the two layers;
• a second step where the magnetization of the first magnetization contribution of the writing layer is reversed by 180° compared to its orientation in the initial step;
• a third step where the magnetization of the second magnetization contribution of the writing layer is reversed by 180° compared to its direction in the initial state;
• a fourth step where the magnetization of the ferromagnetic storage layer is reversed by 180° compared to its direction in the initial state due to magnetostatic interactions between the ferromagnetic storage layer and the writing layer;
• a final step where the magnetization of the ferromagnetic storage layer and the net magnetization of the writing layer is reversed by 180° in respect to their respective orientations in the initial step.