Stray magnetic shielding for a non-volatile MRAM
AssigneeMotorola, Inc.
InventorsClarence J. Tracy, Eugene Chen, Mark Durlam, Theodore Zhu, Saied N. Tehrani
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Abstract
A non-volatile magneto-resistive memory positioned on a semiconductor substrate is shielded from stray magnetic fields by a passivation layer partially or completely surrounding the non-volatile magneto-resistive memory. The passivation layer includes non-conductive ferrite materials, such as Mn--Zn-Ferrite, Ni--Zn-Ferrite, MnFeO, CuFeO, FeO, or NiFeO, for shielding the non-volatile magneto-resistive memory from stray magnetic fields. The non-conductive ferrite materials may also be in the form of a layer which focuses internally generated magnetic fields on the non-volatile magneto-resistive memory to reduce power requirements.
Claims15
A non-volatile magneto-resistive memory with stray magnetic shielding comprising:
- a non-volatile magneto-resistive memory positioned on a substrate and defining an upper surface;
- and
- a passivation layer at least partially surrounding the non-volatile magneto-resistive memory, the passivation layer including ferrite materials for shielding the non-volatile magneto-resistive memory from stray magnetic fields.
A non-volatile magneto-resistive memory with stray magnetic shielding comprising:
- a non-volatile magneto-resistive memory positioned on a substrate and defining an upper surface, the non-volatile magneto-resistive memory including at least first and second layers of magneto-resistive material separated by a layer of non-magnetic material;
- a layer of high permeability, non-conductive magnetic material positioned adjacent the upper surface of the non-volatile magneto-resistive memory so as to focus internally generated magnetic fields on at least one of the first and second layers of magneto-resistive material and shield the non-volatile magneto-resistive memory from stray magnetic fields;
- and
- a passivation layer at least partially surrounding the layer of high permeability, non-conductive magnetic material and the non-volatile magneto-resistive memory.
A non-volatile magneto-resistive memory with stray magnetic shielding comprising:
- a non-volatile magneto-resistive memory positioned on a semiconductor substrate, the non-volatile magneto-resistive memory including an array of individual cells with each cell including at least first and second layers of magneto-resistive material separated by a layer of non-magnetic material, the non-volatile magneto-resistive memory further including integrated circuitry addressing and controlling the individual cells with input/output terminals;
- and
- a layer of high permeability, non-conductive magnetic material coating at least an upper surface of the non-volatile magneto-resistive memory so as to focus internally generated magnetic fields on at least one of the first and second layers of magneto-resistive material in each of the individual cells and shield the non-volatile magneto-resistive memory from stray magnetic fields.
Dependencies are inferred from the claim text.