Abstract: The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated Giant-Magneto-resistive (GMR) structures. The present teachings relates to integrated latch memory and logic devices and, in particular, concerns a spin dependent logic device that may be integrated with conventional semiconductor-based logic devices to construct high-speed non-volatile static random access memory (SRAM) cells.

Abstract: The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated Giant-Magneto-resistive (GMR) structures. The present teachings relates to integrated latch memory and logic devices and, in particular, concerns a spin dependent logic device that may be integrated with conventional semiconductor-based logic devices to construct high-speed non-volatile static random access memory (SRAM) cells.

Abstract: A magnetic shield is presented. The shield may be used to protect a microelectronic device from stray magnetic fields. The shield includes at least two layers. A first layer includes a magnetic material that may be used to block DC magnetic fields. A second layer includes a conductive material that may be used to block AC magnetic fields. Depending on the type of material that the first and second layers include, a third layer may be inserted in between the first and second layers. The third layer may include a non-conductive material that may be used to ensure that separate eddy current regions form in the first and second layers.

Abstract: A magnetic memory and a method of operating the memory are described. The memory includes memory cells that may each include a magnetoresistive bit. The memory cells may each be coupled to a current driver. Each current driver may be inhibited so that it does not output a current. Inhibiting the output current prevents the memory from being written. By inhibiting some current drivers and not inhibiting other current drivers, the memory may be partitioned into read only and random access portions.

Abstract: A shielding arrangement for protecting a circuit containing magnetically sensitive materials from external stray magnetic fields. A shield of a material having a relatively high permeability is formed over the magnetically sensitive materials using thin film deposition techniques. Alternatively, a planar shield is affixed directly to a surface of semiconductor die containing an integrated circuit structure.

Abstract: An improved MRAM cell may include a first, second, and third contact, a first MTJ between the first and second contact, and a MTJ between the second and third contact. The MRAM cell is nonconductive between the first and second MTJ. The first MTJ may include a first free layer with a first switching field, and the second MTJ may include a second free layer with a second switching field. If the first switching field is substantially higher than the second switching field, the first MTJ may be a reference element for the second MTJ. If the first switching field is adequately higher than the second switching field, the first and second MTJ may each contain a data bit. If the first switching field is substantially similar to the second switching field, the first and second MTJs may contain identical data bits connected in series.

Abstract: A magnetic random access memory (MRAM) and a method for reading an MRAM is described. The MRAM may include a magnetoresistive bit, a read architecture coupled to the magnetoresistive bit that forms a read path with the magnetoresistive bit for performing a read operation on the magnetoresistive bit, and a resistive element in the read path that adjusts resistive properties of the magnetoresistive bit during the read operation. Preferably, the resistive element will act in series with the magnetoresistive bit. The resistive element may be a resistive element between the magnetoresistive bit and the read architecture. Alternatively, the resistive element may be a layer of the magnetoresistive bit. Alternatively yet, the resistive element may be an element of the read architecture.

Abstract: A new read scheme is provided for an MRAM bit having a reference layer (fixed) and a storage layer (free) sandwiching a nonmagnetic spacer layer. The reference layer has a magnetization direction that is tilted with respect to an easy axis of the storage layer. By applying a magnetic field to the bit at least partially orthogonal to the easy axis, the magnetization direction of the storage layer can be partially rotated or canted without switching the logical state of the MRAM bit. The resistivity of the bit is measured (calculated based on a voltage/current relationship) in two ways: (i) with the magnetization direction of the storage layer partially rotated in a first direction and (ii) with the magnetization direction of the storage layer in its bi-stable orientation parallel to the easy axis. Those measures can then be used to compare and determine the logical state of the storage layer.

Abstract: A nonvolatile memory and a method of operating the memory are described. The memory includes memory cells that may each include a magnetoresistive memory bit. The memory includes toggle circuitry for altering the resistive states of memory cells within the memory without changing the logical states of the memory cells. The memory may be toggled to balance resistive decay associated with operating a memory bit under certain conditions or in extreme environments.

Abstract: An improved magnetoresistive element may include a pinned magnetic structure, a free magnetic structure, and a spacer layer coupled between the pinned magnetic structure and the free magnetic structure, where the free magnetic structure includes (i) a synthetic anti-ferromagnetic structure (SAF) including two or more anti-ferromagnetically coupled ferromagnetic layers, and (ii) a first biasing layer coupled to the SAF that impedes a decoupling of the two or more anti-ferromagnetically coupled ferromagnetic layers. The first biasing layer may be an anti-ferromagnetic layer, and may be weakly coupled to the SAF. The free magnetic structure may also include (i) a second biasing layer coupled to the SAF that further impedes a decoupling of the two or more anti-ferromagnetically coupled ferromagnetic layers, and/or (ii) a non-magnetic layer coupled between the first biasing layer and the SAF that controls a coupling strength between the first biasing layer and the SAF.

Abstract: An improved MRAM cell may include a first, second, and third contact, a first MTJ between the first and second contact, and a MTJ between the second and third contact. The MRAM cell is nonconductive between the first and second MTJ. The first MTJ may include a first free layer with a first switching field, and the second MTJ may include a second free layer with a second switching field. If the first switching field is substantially higher than the second switching field, the first MTJ may be a reference element for the second MTJ. If the first switching field is adequately higher than the second switching field, the first and second MTJ may each contain a data bit. If the first switching field is substantially similar to the second switching field, the first and second MTJs may contain identical data bits connected in series.

Abstract: A magneto-resistive memory system is presented that includes a radiation-hardened and low power memory cell. The magneto-resistive memory cell includes a word line select transistor in the cell to help eliminate unselected cell disturbances. Furthermore, the magneto-resistive memory cell includes a full-turn write word line that writes true and complimentary bit values using less current than previous cell architectures. The improved memory cell may be used in a memory system with precision current drivers and auto-zero sense amplifiers in order to further lower power and improve overall system reliability.

Abstract: A giant magnetoresistive memory device includes a magnetic sense layer, a magnetic storage layer, a non-magnetic spacer layer between the magnetic sense layer and the magnetic storage layer, and an antiferromagnetic layer formed in proximity to the magnetic storage layer. The antiferromagnetic layer couples magnetically in a controlled manner to the magnetic storage layer such that the magnetic storage layer has uniform and/or directional magnetization. Additionally or alternatively, an antiferromagnetic layer may be formed in proximity to the magnetic sense layer. The antiferromagnetic layer in proximity to the magnetic sense layer couples magnetically in a controlled manner to the magnetic sense layer such that the magnetic sense layer has uniform and/or directional magnetization.

Abstract: The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated Giant-Magneto-resistive (GMR) structures. The present teachings relates to integrated latch memory and logic devices and, in particular, concerns a spin dependent logic device that may be integrated with conventional semiconductor-based logic devices to construct high-speed non-volatile static random access memory (SRAM) cells.

Abstract: In a method of fabricating a giant magnetoresistive (GMR) device a plurality of magnetoresistive device layers is deposited on a first silicon nitride layer formed on a silicon oxide layer. An etch stop is formed on the magnetoresistive device layers, and a second layer of silicon nitride is formed on the etch stop. The magnetoresistive device layers are patterned to define a plurality of magnetic bits having sidewalls. The second silicon nitride layer is patterned to define electrical contact portions on the etch stop in each magnetic bit. The sidewalls of the magnetic bits are covered with a photoresist layer. A reactive ion etch (RIE) process is used to etch into the first silicon nitride and silicon oxide layers to expose electrical contacts. The photoresist layer and silicon nitride layers protect the magnetoresistive layers from exposure to oxygen during the etching into the silicon oxide layer.

Abstract: The semiconductor industry seeks to reduce the risk of traditional volatile storage devices with improved non-volatile storage devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated giant-magneto-resistive (GMR) structures. In an embodiment, a save-on-power-down circuit that may be integrated with conventional semiconductor-based computing, logic, and memory devices to retain volatile logic states and/or volatile digital information in a non-volatile manner is provided.

Abstract: A magnetoresistive device is provided with separate read and write architecture. In one embodiment, a magnetic tunnel junction (MTJ) has a nonmagnetic nonconductive barrier layer sandwiched between two ferromagnetic conducting layers. A first read line is coupled to a first ferromagnetic layer and a second read line is coupled to a second ferromagnetic layer such that a voltage difference between the two read lines will produce a current flowing perpendicularly through each layer of the MTJ. A first write line is separated from the first read line by a first insulator and a second write line is separated from the second read line by a second insulator.

Abstract: A magnetoresistive device is provided with separate read and write architecture. In one embodiment, a magnetic tunnel junction (MTJ) has a nonmagnetic nonconductive barrier layer sandwiched between two ferromagnetic conducting layers. A first read line having a first resistance is coupled to a first ferromagnetic layer and a second read line having a third resistance is coupled to a second ferromagnetic layer such that a voltage difference between the two read lines will produce a current flowing perpendicularly through each layer of the MTJ. A first write line having a second resistance is separated from the first read line by a first insulator and a second write line having a fourth resistance is separated from the second read line by a second insulator, and wherein the second and fourth resistances are lower than the first and third resistance.

Abstract: The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated Giant-Magneto-resistive (GMR) structures. The present teachings relates to integrated latch memory and logic devices and, in particular, concerns a spin dependent logic device that may be integrated with conventional semiconductor-based logic devices to construct high-speed non-volatile static random access memory (SRAM) cells.

Abstract: A magnetic shield is presented. The shield may be used to protect a microelectronic device from stray magnetic fields. The shield includes at least two layers. A first layer includes a magnetic material that may be used to block DC magnetic fields. A second layer includes a conductive material that may be used to block AC magnetic fields. Depending on the type of material that the first and second layers include, a third layer may be inserted in between the first and second layers. The third layer may include a non-conductive material that may be used to ensure that separate eddy current regions form in the first and second layers.