Abstract:
A magnetoresistive element for a two-dimensional magnetic field sensor, including: a ferromagnetic reference layer having a fixed reference magnetization, a ferromagnetic sense layer having a sense magnetization that can be freely oriented relative to the reference magnetization in the presence of an external magnetic field, and a tunnel barrier layer between the reference and sense ferromagnetic layers; the reference layer including a reference coupling layer between a reference pinned layer and a reference coupled layer; the reference coupled layer including a first coupled sublayer in contact with the reference coupling layer, a second coupled sublayer, a third coupled sublayer and a insert layer between the second and third coupled sublayers; the insert layer comprising a transition metal and has a thickness between about 0.1 and about 0.5 nm, and the thickness of the reference coupled layer is between about 1 nm and about 5 nm.
Abstract:
A thermally assisted switching MRAM element including a magnetic tunnel junction including a reference layer having a reference magnetization; a storage layer having a storage magnetization; a tunnel barrier layer included between the storage layer and the reference layer; and a storage antiferromagnetic layer exchange-coupling the storage layer such as to pin the storage magnetization at a low temperature threshold and to free it at a high temperature threshold. The antiferromagnetic layer includes: at least one first antiferromagnetic layer having a first storage blocking temperature, and at least one second antiferromagnetic layer having a second storage blocking temperature; wherein the first storage blocking temperature is below 200° C. and the second storage blocking temperature is above 250° C. The MRAM element combines better data retention compared with known MRAM elements with low writing mode operating temperature.
Abstract:
Magnetic field sensor for sensing a two-dimensional external magnetic field, including a magnetic tunnel junction including a reference layer having a fixed reference magnetization, a sense ferromagnetic layer having a sense magnetization, and a tunnel barrier layer between the sense and reference ferromagnetic layers; the sense ferromagnetic layer including a first sense ferromagnetic layer in contact with the tunnel barrier layer, a second sense ferromagnetic layer, and a first non-magnetic layer between the first and second sense ferromagnetic layers; the second sense ferromagnetic layer includes a plurality of multilayer element, each multilayer element including a second non-magnetic layer between two second ferromagnetic sense layers; and wherein the second sense ferromagnetic layer has a thickness equal or less than 12 nm.
Abstract:
A thermally assisted switching MRAM element including a magnetic tunnel junction including a reference layer having a reference magnetization; a storage layer having a storage magnetization; a tunnel barrier layer included between the storage layer and the reference layer; and a storage antiferromagnetic layer exchange-coupling the storage layer such as to pin the storage magnetization at a low temperature threshold and to free it at a high temperature threshold. The antiferromagnetic layer includes: at least one first antiferromagnetic layer having a first storage blocking temperature, and at least one second antiferromagnetic layer having a second storage blocking temperature; wherein the first storage blocking temperature is below 200° C. and the second storage blocking temperature is above 250° C. The MRAM element combines better data retention compared with known MRAM elements with low writing mode operating temperature.