Manufacturing method of spin-valve magnetoresistive thin film element

A method for manufacturing a dual spin-valve magnetoresistive thin film element, wherein the element includes:

• a free magnetic layer;
• first and second nonmagnetic electrically conductive layers, wherein the first nonmagnetic electrically conductive layer resides below the free magnetic layer and wherein the second nonmagnetic electrically conductive layer overlies the free magnetic layer;
• first and second dual pinned magnetic layers, each of said dual pinned magnetic layers including a first pinned magnetic layer and a second pinned magnetic layer separated by a nonmagnetic intermediate layer, wherein the first dual pinned magnetic layer resides below the first nonmagnetic electrically conductive layer and wherein the second dual pinned magnetic layer overlies the second nonmagnetic electrically conductive layer;
• first and second antiferromagnetic layers, wherein the first antiferromagnetic layer resides below the first dual pinned magnetic layer, and wherein the second antiferromagnetic layer overlies the second dual pinned magnetic layer, and
• wherein said first pinned magnetic layer of said first dual pinned magnetic layer contacts said first antiferromagnetic layer and wherein said second pinned magnetic layer of said first dual pinned magnetic layer contacts said first nonmagnetic electrically conductive layer, and wherein said first pinned magnetic layer of said second dual pinned magnetic
• layer contacts said second antiferromagnetic layer and wherein said second pinned magnetic layer of said second dual pinned magnetic layer contacts said second nonmagnetic electrically conductive layer;
• said method comprising the steps of:
• forming magnetic moments of said first and second pinned magnetic layers to have different values, wherein the magnetic moment is the product of the saturation magnetization and the magnetic film thickness, by carrying out a process selected from the group consisting of:
• a) forming said second dual pinned magnetic layer such that said first pinned magnetic layer has a greater magnetic moment than said second pinned magnetic layer, and forming said first dual pinned magnetic layer such that said first pinned magnetic layer has a smaller magnetic moment than said second pinned magnetic layer;
• and
• b) forming said second dual pinned magnetic layer such that said first pinned magnetic layer has a smaller magnetic moment than said second pinned magnetic layer, and forming said first dual pinned magnetic layer such that said first pinned magnetic layer has a greater magnetic moment than said second pinned magnetic layer;
• thermally treating said first and second dual pinned magnetic layers while applying a magnetic field of at least about 5000 Oe in a first direction to pin the first pinned magnetic layers of the first and second dual pinned magnetic layers in the first direction.

A method for manufacturing a dual spin-valve magnetoresistive thin film element, wherein the element includes:

• a free magnetic layer;
• first and second nonmagnetic electrically conductive layers, wherein the first nonmagnetic electrically conductive layer resides below the free magnetic layer and wherein the second nonmagnetic electrically conductive layer overlies the free magnetic layer;
• first and second dual pinned magnetic layers, each of said dual pinned magnetic layers including a first pinned magnetic layer and a second pinned magnetic layer separated by a nonmagnetic intermediate layer, wherein the first dual pinned magnetic layer resides below the first nonmagnetic electrically conductive layer and wherein the second dual pinned magnetic layer overlies the second nonmagnetic electrically conductive layer;
• first and second antiferromagnetic layers, wherein the first antiferromagnetic layer resides below the first dual pinned magnetic layer, and wherein the second antiferromagnetic layer overlies the second dual pinned magnetic layer, and
• wherein said first pinned magnetic layer of said first dual pinned magnetic layer contacts said first antiferromagnetic layer and wherein said second pinned magnetic layer of said first dual pinned magnetic layer contacts said first nonmagnetic electrically conductive layer, and
• wherein said first pinned magnetic layer of said second dual pinned magnetic layer contacts said second antiferromagnetic layer and wherein said second pinned magnetic layer of said second dual pinned magnetic layer contacts said second nonmagnetic electrically conductive layer;
• said method comprising the steps of:
• forming magnetic moments of said first and second pinned magnetic layers to have different values, wherein the magnetic moment is the product of the saturation magnetization and the magnetic film thickness;
• thermally treating said first and second dual pinned magnetic layers, while applying a magnetic field to pin said first pinned magnetic layer in a first direction by selecting a process from the group consisting of:
• a) when the magnetic moment of said first pinned magnetic layer of said first and second dual pinned magnetic layers is greater than the magnetic moment of said second pinned magnetic layer of said first and second dual pinned magnetic layers, applying said magnetic field having a magnitude selected from the group consisting of about 100 to about 1000 Oe, and no less than about 5000 Oe in said first direction, and
• b) when said magnetic moment of said first pinned magnetic layer of said first and second dual pinned magnetic layers is less than the magnetic moment of said second pinned magnetic layer of said first and second dual pinned magnetic layers, selecting a process selected from the group consisting of
• i) applying said magnetic field having a magnitude of about 100 to about 1000 Oe in a second direction opposite to said first direction, and
• ii) applying said magnetic field having a magnitude of no less than about 5000 Oe in said first direction.

A method for manufacturing a dual spin-valve magnetoresistive thin film element, wherein the element includes:

• a divided free magnetic layer including a first free magnetic layer and a second free magnetic layer separated by a nonmagnetic intermediate layer;
• first and second nonmagnetic electrically conductive layers, wherein said first nonmagnetic electrically conductive layer resides below said divided free magnetic layer and wherein said second nomnagnetic electrically conductive layer overlies said divided free magnetic layer;
• first and second dual pinned magnetic layers, each of said dual pinned magnetic layers including a first pinned magnetic layer and a second pinned magnetic layer separated by a nonmagnetic intermediate layer, wherein said first dual pinned magnetic layer resides below said first nonmagnetic electrically conductive layer and wherein said second dual pinned magnetic layer overlies said second nonmagnetic electrically conductive layer;
• first and second antiferromagnetic layers, wherein said first antiferromagnetic layer resides below said first dual pinned magnetic layer, and wherein said second antiferromagnetic layer overlies said second dual pinned magnetic layer, and
• wherein said first pinned magnetic layer of said first dual pinned magnetic layer contacts said first antiferromagnetic layer and wherein said second pinned magnetic layer of said first dual pinned magnetic layer contacts said first nonmagnetic electrically conductive layer, and
• wherein said first pinned magnetic layer of said second dual pinned magnetic layer contacts said second antiferromagnetic layer and wherein said second pinned magnetic layer of said second dual pinned magnetic layer contacts said second nonmagnetic electrically conductive layer;
• said method comprising the steps of:
• forming magnetic moments of said first and second pinned magnetic layers to have different value, wherein the magnetic moment is the product of the saturation magnetization and the magnetic film thickness, by carrying out a process selected from the group consisting of:
• a) forming said second dual pinned magnetic layer such that said first pinned magnetic layer has a greater magnetic moment than said second pinned magnetic layer, and forming said first dual pinned magnetic layer such that said first pinned magnetic layer has a smaller magnetic moment than said second pinned magnetic layer;
• and
• b) forming said second dual pinned magnetic layer such that said first pinned magnetic layer has a smaller magnetic moment than said second pinned magnetic layer, and forming said first dual pinned magnetic layer such that said first pinned magnetic layer has a greater magnetic moment than said second pinned magnetic layer;
• thermally treating said first and second dual pinned magnetic layers while applying a magnetic field of about 100 to about 1000 Oe in a first direction to pin said first and second magnetic layers, such that
• (c) when said forming magnetic moments of said first and second pinned magnetic layers to have different value is said a) process, said first pinned magnetic layer of said second dual pinned magnetic layer is pinned in a first direction, and said second pinned magnetic layer of said second dual pinned magnetic layer is pinned in a second direction opposite to said first direction,
• (d) when said forming magnetic moments of said first and second pinned magnetic layers to have different value is said b) process, said first pinned magnetic layer of said second dual pinned magnetic layer is pinned in the second direction opposite to said first direction, and said second pinned magnetic layer of said second dual pinned magnetic layer is pinned in the first direction.