Patent application number | Description | Published |
20090130779 | Method of Forming a Magnetic Tunnel Junction Structure - In a particular embodiment, a method is disclosed that includes forming a magnetic tunnel junction (MTJ) structure including a conductive layer on a substrate. The method also includes depositing a sacrificial layer on the conductive layer before depositing a patterning film layer. | 05-21-2009 |
20090161422 | Magnetic Tunnel Junction Device with Separate Read and Write Paths - In an embodiment, a device is disclosed that includes a magnetic tunnel junction (MTJ) structure. The device also includes a read path coupled to the MTJ structure and a write path coupled to the MTJ structure. The write path is separate from the read path. | 06-25-2009 |
20090243009 | Magnetic Tunnel Junction Cell Including Multiple Vertical Magnetic Domains - Magnetic tunnel junction cell including multiple vertical domains. In an embodiment, a magnetic tunnel junction (MTJ) structure is disclosed. The MTJ structure includes an MTJ cell. The MTJ cell includes multiple vertical side walls. Each of the multiple vertical side walls defines a unique vertical magnetic domain. Each of the unique vertical magnetic domains is adapted to store a digital value. | 10-01-2009 |
20090261434 | STT MRAM Magnetic Tunnel Junction Architecture and Integration - A magnetic tunnel junction (MTJ) device for a magnetic random access memory (MRAM) in a semiconductor back-end-of-line (BEOL) process flow includes a first metal interconnect for communicating with at least one control device and a first electrode for coupling to the first metal interconnect through a via formed in a dielectric passivation barrier using a first mask. The device also includes an MTJ stack for storing data coupled to the first electrode, a portion of the MTJ stack having lateral dimensions based upon a second mask. The portion defined by the second mask is over the contact via. A second electrode is coupled to the MTJ stack and also has a same lateral dimension as defined by the second mask. The first electrode and a portion of the MTJ stack are defined by a third mask. A second metal interconnect is coupled to the second electrode and at least one other control device. | 10-22-2009 |
20090321859 | System and Method to Fabricate Magnetic Random Access Memory - A system and method to fabricate magnetic random access memory is disclosed. In a particular embodiment, the method includes depositing a cap layer on a magnetic tunnel junction (MTJ) structure, depositing a first spin-on material layer over the cap layer, and etching the first spin-on material layer and at least a portion of the cap layer. | 12-31-2009 |
20090323410 | System and Method to Fabricate Magnetic Random Access Memory - A system and method to fabricate magnetic random access memory is disclosed. In a particular embodiment, a method of aligning a magnetic film during deposition is disclosed. The method includes applying a first magnetic field along a first direction in a region in which a substrate resides during a deposition of a first magnetic material onto the substrate. The method further includes applying a second magnetic field along a second direction in the region during the deposition of the first magnetic material onto the substrate. | 12-31-2009 |
20100039136 | Gate Level Reconfigurable Magnetic Logic - A re-programmable gate logic includes a plurality of non-volatile re-configurable resistance state-based memory circuits in parallel, wherein the circuits are re-configurable to implement or change a selected gate logic, and the plurality of non-volatile re-configurable resistance state-based memory circuits are each adapted to receive a logical input signal. An evaluation switch in series with the plurality of parallel non-volatile re-configurable resistance state-based memory circuits is configured to provide an output signal based on the programmed states of the memory circuits. A sensor is configured to receive the output signal and provide a logical output signal on the basis of the output signal and a reference signal provided to the sensor. The reconfigurable logic may be implemented based on using spin torque transfer (STT) magnetic tunnel junction (MTJ) magnetoresistance random access memory (MRAM) as the re-programmable memory elements. The logic configuration is retained without power. | 02-18-2010 |
20100074092 | Reducing Spin Pumping Induced Damping of a Free Layer of a Memory Device - A system and method of reducing spin pumping induced damping of a free layer of a memory device is disclosed. The memory device includes an anti-ferromagnetic material (AFM) pinning layer in contact with a bit line access electrode. The memory device also includes a pinned layer in contact with the AFM pinning layer, a tunnel barrier layer in contact with the pinned layer, and a free layer in contact with the tunnel barrier layer. The memory device includes a spin torque enhancing layer in contact with the free layer and in contact with an access transistor electrode. The spin torque enhancing layer is configured to substantially reduce spin pumping induced damping of the free layer. | 03-25-2010 |
20100102404 | Magnetic Tunnel Junction and Method of Fabrication - In a particular embodiment, a method of forming a magnetic tunnel junction (MTJ) device includes applying a dielectric layer to a surface, applying a metal layer to the dielectric layer, and adding a cap layer on the dielectric layer. The method also includes forming a magnetic tunnel junction (MTJ) stack such that an electrode of the MTJ stack is disposed on the metal layer and the cap layer contacts a side portion of the metal layer. An adjustable depth to via may connect a top electrode of the MTJ stack to a top metal. | 04-29-2010 |
20100176471 | Magnetic Element With Storage Layer Materials - According to an embodiment of the invention, a magnetic tunnel junction (MTJ) element includes a reference ferromagnetic layer, a storage ferromagnetic layer, and an insulating layer. The storage ferromagnetic layer includes a CoFeB sub-layer coupled to a CoFe sub-layer and/or a NiFe sub-layer through a non-magnetic sub-layer. The insulating layer is disposed between the reference and storage ferromagnetic layers. | 07-15-2010 |
20100188894 | IN-SITU RESISTANCE MEASUREMENT FOR MAGNETIC RANDOM ACCESS MEMORY (MRAM) - A method of measuring resistance of a magnetic tunnel junction (MTJ) of an MRAM memory cell includes applying a voltage of a selected level to a memory cell comprising an MTJ in series with a memory cell transistor in a conducting state. A current through the memory cell is determined. A variable voltage is applied to a replica cell not having an MTJ and comprising a replica cell transistor in a conducting state. A value of the variable voltage is determined, wherein a resulting current through the replica cell is substantially the same as the current through the memory cell. The MTJ resistance is computed by taking the difference of the memory cell voltage and the determined variable replica cell voltage and dividing the result by the determined memory cell current. | 07-29-2010 |
20100193888 | Magnetic Tunnel Junction (MTJ) Storage Element and Spin Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) Cells Having an MJT - A magnetic tunnel junction storage element for a spin transfer torque magnetoresistive random access memory (STT-MRAM) bit cell includes a bottom electrode layer, a pinned layer adjacent to the bottom electrode layer, a dielectric layer encapsulating a portion of the bottom electrode layer and the pinned layer, the dielectric layer including sidewalls that define a hole adjacent to a portion of the pinned layer, a tunneling barrier adjacent to the pinned layer, a free layer adjacent to the tunneling barrier, and a top electrode adjacent to the free layer, wherein a width of the bottom electrode layer and/or the pinned barrier in a first direction is greater than a width of a contact area between the pinned layer and the tunneling barrier in the first direction. Also a method of forming an STT-MRAM bit cell. | 08-05-2010 |
20100207221 | Magnetic Random Access Memory - A device includes a magnetic tunnel junction (MTJ) structure and a cap layer in contact with the MTJ structure. The device also includes a spin-on material layer in contact with a sidewall portion of the cap layer and a conducting layer in contact with at least the spin-on material layer and a portion of the MTJ structure. The cap layer has been etched to expose a portion of an electrode contact layer of the MTJ structure. The conducting layer is in electrical contact with the exposed portion of the electrode contact layer of the MTJ structure. | 08-19-2010 |
20100219491 | Magnetic Tunnel Junction Device and Fabrication - A magnetic tunneling junction device and fabrication method is disclosed. In a particular embodiment, the method includes depositing a capping material on a free layer of a magnetic tunneling junction structure to form the capping layer and oxidizing a portion of the capping material to form a layer of oxidized material. | 09-02-2010 |
20100220516 | Reducing Source Loading Effect in Spin Torque Transfer Magnetoresisitive Random Access Memory (STT-MRAM) - Systems and methods to reduce source loading effects in STT-MRAM are disclosed. In a particular embodiment, a method includes determining a switching current ratio of a magnetic tunnel junction (MTJ) structure that enables stable operation of a memory cell. The memory cell includes the MTJ structure serially coupled to an access transistor. The method also includes modifying an offset magnetic field that is incident to a free layer of the MTJ structure. The modified offset magnetic field causes the MTJ structure to exhibit the switching current ratio. | 09-02-2010 |
20100258887 | Magnetic Tunnel Junction (MTJ) and Methods, and Magnetic Random Access Memory (MRAM) Employing Same - Magnetic tunnel junctions (MTJs) and methods of forming same are disclosed. A pinned layer is disposed in the MTJ such that a free layer of the MTJ can couple to a drain of an access transistor when provided in a magnetic random access memory (MRAM) bitcell. This structure alters the write current flow direction to align the write current characteristics of the MTJ with write current supply capability of an MRAM bitcell employing the MTJ. As a result, more write current can be provided to switch the MTJ from a parallel (P) to anti-parallel (AP) state. An anti-ferromagnetic material (AFM) layer is provided on the pinned layer to fix pinned layer magnetization. To provide enough area for depositing the AFM layer to secure pinned layer magnetization, a pinned layer having a pinned layer surface area greater than a free layer surface area of the free layer is provided. | 10-14-2010 |
20100289098 | Magnetic Tunnel Junction Device and Fabrication - A magnetic tunnel junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, a method is disclosed that includes forming a magnetic tunnel junction (MTJ) device on a structure that includes a bottom cap layer and a bottom metal-filled trench having a normal axis, the magnetic tunnel junction device including a bottom electrode, magnetic tunnel junction layers, a magnetic tunnel junction seal layer, a top electrode, and a logic cap layer, the magnetic tunnel junction device having an MTJ axis that is offset from the normal axis. | 11-18-2010 |
20100302843 | Spin Transfer Torque - Magnetic Tunnel Junction Device and Method of Operation - A method is disclosed that includes controlling current flow direction for current sent over a source line or a bit line of a magnetic memory device. A current generated magnetic field assists switching of a direction of a magnetic field of a free layer of a magnetic element within a spin transfer torque magnetic tunnel junction (STT-MTJ) device. | 12-02-2010 |
20100315863 | Magnetic Tunnel Junction Device and Fabrication - A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a free layer and a spin torque enhancing layer. The spin torque enhancing layer includes a nano-oxide layer. | 12-16-2010 |
20110051509 | System and Method to Manufacture Magnetic Random Access Memory - A system and method to manufacture magnetic random access memory is disclosed. In a particular embodiment, a method of making a magnetic tunnel junction memory system includes forming a portion of a metal layer into a source line having a substantially rectilinear portion. The method also includes coupling the source line, at the substantially rectilinear portion, to a first transistor using a first via. The first transistor is configured to supply a first current received from the source line to a first magnetic tunnel junction device. The method includes coupling the source line to a second transistor using a second via, where the second transistor is configured to supply a second current received from the source line to a second magnetic tunnel junction device. | 03-03-2011 |
20110090732 | Magnetic Tunnel Junction Cell Adapted to Store Multiple Digital Values - A particular magnetic tunnel junction (MTJ) cell includes a side wall defining a first magnetic domain adapted to store a first digital value. The MTJ cell also includes a bottom wall coupled to the side wall and defining a second magnetic domain adapted to store a second digital value. | 04-21-2011 |
20110121417 | Magnetic Tunnel Junction Device and Fabrication - A magnetic tunnel junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, a method is disclosed that includes forming a magnetic tunnel junction structure above a bottom electrode. The method also includes forming a diffusion barrier layer above and adjacent to the magnetic tunnel junction structure. The method further includes etching back the diffusion barrier layer, removing the diffusion barrier layer above the magnetic tunnel junction structure. The method also includes connecting a top of the magnetic tunnel junction structure to a conductive layer. | 05-26-2011 |
20110133299 | Magnetic Tunnel Junction Device - A system and method of manufacturing and using a magnetic tunnel junction device is disclosed. In a particular embodiment, a magnetic tunnel junction device includes a first free layer and second free layer. The magnetic tunnel junction also includes a spin torque enhancement layer. The magnetic tunnel junction device further includes a spacer layer between the first and second free layers that includes a material and has a thickness that substantially inhibits exchange coupling between the first and second free layers. The first and second free layers are magneto-statically coupled. | 06-09-2011 |
20110141796 | Magnetic Tunnel Junction Device and Fabrication - A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a barrier layer, a free layer, and a magnesium (Mg) capping layer. The free layer is positioned between the barrier layer and the magnesium (Mg) capping layer. | 06-16-2011 |
20110169112 | Composite Hardmask Architecture and Method of Creating Non-Uniform Current Path for Spin Torque Driven Magnetic Tunnel Junction - A magnetic tunnel junction (MTJ) storage element and method of forming the MTJ are disclosed. The magnetic tunnel junction (MTJ) storage element includes a pinned layer, a barrier layer, a free layer and a composite hardmask or top electrode. The composite hardmask/top electrode architecture is configured to provide a non-uniform current path through the MTJ storage element and is formed from electrodes having different resistance characteristics coupled in parallel. An optional tuning layer interposed between the free layer and the top electrode helps to reduce the damping constant of the free layer. | 07-14-2011 |
20110175181 | Magnetic Tunnel Junction (MTJ) on Planarized Electrode - A magnetic tunnel junction (MTJ) with direct contact is manufactured having lower resistances, improved yield, and simpler fabrication. The lower resistances improve both read and write processes in the MTJ. The MTJ layers are deposited on a bottom electrode aligned with the bottom metal. An etch stop layer may be deposited adjacent to the bottom metal to prevent overetch of an insulator surrounding the bottom metal. The bottom electrode is planarized before deposition of the MTJ layers to provide a substantially flat surface. Additionally, an underlayer may be deposited on the bottom electrode before the MTJ layers to promote desired characteristics of the MTJ. | 07-21-2011 |
20110186946 | Magnetic Tunnel Junction with Domain Wall Pinning - Magnetic tunnel junctions (MTJs) are manufactured having pinning sites in a ferromagnetic layer of the MTJ. The pinning sites are created using patterns in the photomask used during patterning of the ferromagnetic layer without adding additional processes to manufacturing of the MTJs. The pinning sites create energy barriers substantially preventing a domain wall in the ferromagnetic layer from passing into fixed regions of the ferromagnetic layer. Additionally, the pinning sites substantially prevent a domain wall in the ferromagnetic layer from returning to the middle of the free region. Pinning the domain wall at the boundary of the fixed region and the free region the ferromagnetic layer improves reliability and sensitivity of the MTJ. The ferromagnetic layer may be magnetized in a direction perpendicular to the plane of the ferromagnetic layer. | 08-04-2011 |
20110233695 | Magnetoresistive Random Access Memory (MRAM) With Integrated Magnetic Film Enhanced Circuit Elements - A Magnetoresistive Random Access Memory (MRAM) integrated circuit includes a substrate, a magnetic tunnel junction region, a magnetic circuit element, and an integrated magnetic material. The magnetic tunnel junction region is disposed on the substrate, and includes a first magnetic layer and a second magnetic layer separated by a tunnel barrier insulating layer. The magnetic circuit element region is disposed on the substrate, and includes a plurality of interconnected metal portions. The integrated magnetic material is disposed on the substrate adjacent to the plurality of interconnected metal portions. | 09-29-2011 |
20110249490 | Asymmetric Write Scheme for Magnetic Bit Cell Elements - Asymmetric switching is defined for magnetic bit cell elements. A magnetic bit cell for memory and other devices includes a transistor coupled to an MTJ structure. A bit line is coupled at one terminal of the bit cell to the MTJ structure. At another terminal of the bit cell, a source line is coupled to the source/drain terminal of the transistor. The bit line is driven by a bit line driver that provides a first voltage. The source line is driven by a source line driver that provides a second voltage. The second voltage is larger than the first voltage. The switching characteristics of the bit cell and MTJ structure are improved and made more reliable by one or a combination of applying the higher second voltage to the source line and/or reducing the overall parasitic resistance in the magnetic bit cell element. | 10-13-2011 |
20110273926 | Method and Apparatus of Probabilistic Programming Multi-Level Memory in Cluster States Of Bi-Stable Elements - A probabilistic programming current is injected into a cluster of bi-stable probabilistic switching elements, the probabilistic programming current having parameters set to result in a less than unity probability of any given bi-stable switching element switching, and a resistance of the cluster of bi-stable switching elements is detected. The probabilistic programming current is injected and the resistance of the cluster state detected until a termination condition is met. Optionally the termination condition is detecting the resistance of the cluster of bi-stable switching elements at a value representing a multi-bit data. | 11-10-2011 |
20110280065 | Write Energy Conservation In Memory - A method writes data to a resistive memory, such as spin torque transfer magnetic random access memory (STT-MRAM). The method writes received bits of data to a memory cell array, in response to a first write signal. The method also reads stored data from the memory cell array, after the first write signal is generated, and then compares the stored data with the received bits of data to determine whether each of the received bits of data was written to the memory. In response to a second write signal, received bits of data determined not to have been written during the first write signal, are written. | 11-17-2011 |
20120012952 | Magnetic Storage Element Utilizing Improved Pinned Layer Stack - A magnetic tunnel junction (MTJ) storage element may comprise a pinned layer stack and a first functional layer. The pinned layer stack is formed of a plurality of layers comprising a bottom pinned layer, a coupling layer, and a top pinned layer. The first functional layer is disposed in the bottom pinned layer or the top pinned layer. | 01-19-2012 |
20120032287 | MRAM Device and Integration Techniques Compatible with Logic Integration - A semiconductor device includes a magnetic tunnel junction (MTJ) storage element configured to be disposed in a common interlayer metal dielectric (IMD) layer with a logic element. Cap layers separate the common IMD layer from a top and bottom IMD layer. Top and bottom electrodes are coupled to the MTJ storage element. Metal connections to the electrodes are formed in the top and bottom IMD layers respectively through vias in the separating cap layers. Alternatively, the separating cap layers are recessed and the bottom electrodes are embedded, such that direct contact to metal connections in the bottom IMD layer is established. Metal connections to the top electrode in the common IMD layer are enabled by isolating the metal connections from the MTJ storage elements with metal islands and isolating caps. | 02-09-2012 |
20120033490 | Generating a Non-Reversible State at a Bitcell Having a First Magnetic Tunnel Junction and a Second Magnetic Tunnel Junction - A method of generating a non-reversible state at a bitcell having a first magnetic tunnel junction (MTJ) and a second MTJ includes applying a program voltage to the first MTJ of the bitcell without applying the program voltage to the second MTJ of the bitcell. A memory device includes a bitcell having a first MTJ and a second MTJ and programming circuitry configured to generate a non-reversible state at the bitcell by applying a program signal to a selected one of the first MTJ and the second MTJ of the bitcell. | 02-09-2012 |
20120086089 | MAGNETIC TUNNEL JUNCTION DEVICE AND FABRICATION - A magnetic tunnel junction (MTJ) device and fabrication method is disclosed. A particular embodiment includes a magnetic tunnel junction structure above a bottom electrode. The particular embodiment further includes a portion of a diffusion barrier layer adjacent to the magnetic tunnel junction structure. A top of the magnetic tunnel junction structure is connected to a conductive layer. | 04-12-2012 |
20120107966 | MAGNETIC TUNNEL JUNCTION DEVICE AND FABRICATION - A magnetic tunneling junction device and fabrication method is disclosed. In a particular embodiment, the method includes depositing a capping material on a free layer of a magnetic tunneling junction structure to form the capping layer and oxidizing a portion of the capping material to form a layer of oxidized material. | 05-03-2012 |
20120218805 | Configurable Memory Array - Embodiments disclosed include a memory array having a plurality of bit lines and a plurality of source lines disposed in columns. A plurality of word lines is disposed in rows. A plurality of storage elements have a first subset of storage elements electrically decoupled from the memory array and a second subset of storage elements coupled to the memory array. The memory array further includes a plurality of bit cells, each including one storage element from the second subset of storage elements coupled to at least two transistors. The bit cells are coupled to the plurality of bit lines and the plurality source lines. Each transistor is coupled to one word line. The memory array can further include logic to select a high performance mode and a high density mode. | 08-30-2012 |
20130016553 | MRAM Sensing with Magnetically Annealed Reference CellAANM Rao; Hari M.AACI San DiegoAAST CAAACO USAAGP Rao; Hari M. San Diego CA USAANM Zhu; XiaochunAACI San DiegoAAST CAAACO USAAGP Zhu; Xiaochun San Diego CA US - Systems and method for reading/sensing data stored in magnetoresistive random access memory (MRAM) cells using magnetically annealed reference cells. A MRAM includes a reference circuit comprising at least one magnetic storage cell, wherein each magnetic storage cell in the MRAM is programmed to the same state. The reference circuit includes a load element coupled to the magnetic storage cell, wherein the load element is configured to establish a reference voltage during a read operation. | 01-17-2013 |
20130028010 | Fast MTJ Switching Write Circuit For MRAM Array - A transmission gate is arranged between a current source and a resistive memory element, a PMOS gate of the transmission gate has no source loading effect and a write current passes from the current source, and in a first direction through the resistive memory element, setting the resistive memory element to a magnetization state. An NMOS gate of the of the transmission gate has no source loading effect and another write current, passes through the resistive memory element, in a second direction opposite the first direction, and through the transmission gate, setting the resistive memory element to an opposite magnetization state. | 01-31-2013 |
20130062714 | STRAIN INDUCED REDUCTION OF SWITCHING CURRENT IN SPIN-TRANSFER TORQUE SWITCHING DEVICES - Partial perpendicular magnetic anisotropy (PPMA) type magnetic random access memory cells are constructed using processes and structural configurations that induce a directed static strain/stress on an MTJ to increase the perpendicular magnetic anisotropy. Consequently, reduced switching current of the MTJ results. The directed static strain/stress on the MTJ is induced in a controlled direction and/or with a controlled magnitude during fabrication. The MTJ is permanently subject to a predetermined directed stress and permanently includes the directed static strain/strain that provides reduced switching current. | 03-14-2013 |
20130062715 | SYMMETRICALLY SWITCHABLE SPIN-TRANSFER-TORQUE MAGNETORESISTIVE DEVICE - A spin transfer torque magnetic random access memory (STT-MRAM) device includes magnetic tunnel junctions (MTJs) with reduced switching current asymmetry. At least one switching asymmetry balance layer (SABL) near the free layer of the MTJ reduces a first switching current Ic(p-ap) causing the value of the first switching current to be nearly equal to the value of a second switching current Ic(ap-p) without increasing the average switching current of the device. The SABL may be a non-magnetic switching asymmetry balance layer (NM-SABL) and/or a magnetic switching asymmetry balance layer (M-SABL). | 03-14-2013 |
20130073598 | Entropy source with magneto-resistive element for random number generator - An entropy source and a random number (RN) generator are disclosed. In one aspect, a low-energy entropy source includes a magneto-resistive (MR) element and a sensing circuit. The MR element is applied a static current and has a variable resistance determined based on magnetization of the MR element. The sensing circuit senses the resistance of the MR element and provides random values based on the sensed resistance of the MR element. In another aspect, a RN generator includes an entropy source and a post-processing module. The entropy source includes at least one MR element and provides first random values based on the at least one MR element. The post-processing module receives and processes the first random values (e.g., based on a cryptographic hash function, an error detection code, a stream cipher algorithm, etc.) and provides second random values having improved randomness characteristics. | 03-21-2013 |
20130075845 | THERMALLY TOLERANT PERPENDICULAR MAGNETIC ANISOTROPY COUPLED ELEMENTS FOR SPIN-TRANSFER TORQUE SWITCHING DEVICE - Perpendicular magnetic anisotropy (PMA) type magnetic random access memory cells are constructed with a composite PMA layer to provide a magnetic tunnel junction (MTJ) with an acceptable thermal barrier, A PMA coupling layer is deposited between a first PMA layer and a second PMA layer to form the composite PMA layer. The composite PMA layer may be incorporated in PMA type MRAM cells or in-plane type MRAM cells. | 03-28-2013 |
20130076390 | Programmable Logic Sensing in Magnetic Random Access Memory - A Magnetic Random Access Memory (MRAM) logic circuit includes read sensing circuitry having a first level corresponding to a first category of logic circuitry and a second logic level corresponding to a second category of logic circuitry. The logic circuitry may be switchable between circuitry having the first logic level and circuitry having the second logic level according to the category of the logic circuit being implemented. | 03-28-2013 |
20130114336 | THREE PORT MTJ STRUCTURE AND INTEGRATION - A two-transistor one-MTJ (2T1MTJ) three port structure includes two separate pin layer structures coupled to one free layer structure. The pin layer structures may include an anti-ferromagnetic layer (AFM) layer coupled to a pin layer. The free layer structure includes free layer coupled to a barrier layer and a cap layer. The free layer structure may include a thin barrier layer coupled to each of the pin layer stacks. The three port MTJ structure provides separate write and read paths which improve read sensing margin without increasing write voltage or current. The three port MTJ structure may be fabricated with a simple two step MTJ etch process. | 05-09-2013 |
20130121066 | CIRCUIT AND METHOD FOR GENERATING A REFERENCE LEVEL FOR A MAGNETIC RANDOM ACCESS MEMORY ELEMENT - A method of establishing a reference level includes providing first and second non-overlapping paths from a first node to a second node, providing first and second reference magnetic random access memory (MRAM) elements in the first path, providing third and fourth reference MRAM elements in the second path, measuring a first value indicative of a resistance between the first node and the second node, and setting the reference level based at least in part on the measured value. Also an associated reference circuit. | 05-16-2013 |
20130130406 | MAGNETIC TUNNEL JUNCTION DEVICE AND FABRICATION - A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a free layer and a spin torque enhancing layer. The spin torque enhancing layer includes a nano-oxide layer. | 05-23-2013 |
20130134533 | MAGNETIC TUNNEL JUNCTION (MTJ) AND METHODS, AND MAGNETIC RANDOM ACCESS MEMORY (MRAM) EMPLOYING SAME - Magnetic tunnel junctions (MTJs) and methods of forming same are disclosed. A pinned layer is disposed in the MTJ such that a free layer of the MTJ can couple to a drain of an access transistor when provided in a magnetic random access memory (MRAM) bitcell. This structure alters the write current flow direction to align the write current characteristics of the MTJ with write current supply capability of an MRAM bitcell employing the MTJ. As a result, more write current can be provided to switch the MTJ from a parallel (P) to anti-parallel (AP) state. An anti-ferromagnetic material (AFM) layer is provided on the pinned layer to fix pinned layer magnetization. To provide enough area for depositing the AFM layer to secure pinned layer magnetization, a pinned layer having a pinned layer surface area greater than a free layer surface area of the free layer is provided. | 05-30-2013 |
20130161771 | REDUCING SOURCE LOADING EFFECT IN SPIN TORQUE TRANSFER MAGNETORESISTIVE RANDOM ACCESS MEMORY (STT-MRAM) - An apparatus includes a memory cell including a magnetic tunnel junction (MTJ) structure coupled between a bit line and a source line. The MTJ structure includes a free layer coupled to the bit line and a pinned layer. A magnetic moment of the free layer is substantially parallel to a magnetic moment of the pinned layer in a first state and substantially antiparallel to the magnetic moment of the pinned layer in a second state. A physical dimension of the pinned layer produces an unbalanced offset magnetic field which corresponds to a first switching current of the MTJ structure that enables switching from the first state to the second state when a first voltage is applied to the bit line and corresponds to a second switching current that enables switching from the second state to the first state when the first voltage is applied to the source line. | 06-27-2013 |
20130187247 | MULTI-BIT MAGNETIC TUNNEL JUNCTION MEMORY AND METHOD OF FORMING SAME - A spin-torque transfer (STT) magnetic tunnel junction (MTJ) memory includes a unitary fixed magnetic layer, a magnetic barrier layer on the unitary fixed magnetic layer, a free magnetic layer having a plurality of free magnetic islands on the magnetic barrier layer, and a cap layer overlying the free magnetic layer. Also a method of forming an STT-MTJ memory. | 07-25-2013 |
20130201757 | MULTI-FREE LAYER MTJ AND MULTI-TERMINAL READ CIRCUIT WITH CONCURRENT AND DIFFERENTIAL SENSING - A multi-free layer magnetic tunnel junction (MTJ) cell includes a bottom electrode layer, an anti-ferromagnetic layer on the bottom electrode layer, a fixed magnetization layer on the anti-ferromagnetic layer and a barrier layer on the fixed magnetization layer. A first free magnetization layer is on a first area of the barrier layer, and a capping layer is on the first free magnetization layer. A free magnetization layer is on a second area of the barrier layer, laterally displaced from the first area, and a capping layer is on the second free magnetization layer. Optionally current switches establish a read current path including the first free magnetization layer concurrent with not establishing a read current path including the second free magnetization layer. Optionally current switches establishing a read current path including the first and second free magnetization layer. | 08-08-2013 |
20130235656 | MAGNETIC TUNNEL JUNCTION DEVICE AND FABRICATION - An apparatus includes a structure that includes a bottom cap layer surrounding a metal pad. The apparatus also includes a magnetic tunnel junction (MTJ) device that includes a bottom electrode coupled to the structure. The MTJ device includes magnetic tunnel junction layers, a top electrode, and a logic cap layer. The MTJ device is offset with respect to the metal pad. | 09-12-2013 |
20130279244 | HIERARCHICAL MEMORY MAGNETORESISTIVE RANDOM-ACCESS MEMORY (MRAM) ARCHITECTURE - A hierarchical memory magnetoresistive random-access memory architecture is disclosed. In a particular embodiment, an apparatus includes a first magnetoresistive random-access memory (MRAM) device corresponding to a first level in a hierarchical memory system. The apparatus includes a second MRAM device corresponding to a second level in the hierarchical memory system. The first MRAM device has a first access latency and includes a first magnetic tunnel junction (MTJ) device having a first physical configuration. The second MRAM device has a second access latency and includes a second WI device having a second physical configuration. The first access latency is less than the second access latency. | 10-24-2013 |
20130320468 | MAGNETIC ELEMENT WITH STORAGE LAYER MATERIALS - According to an embodiment of the invention, a magnetic tunnel junction (MTJ) element includes a reference ferromagnetic layer, a storage ferromagnetic layer, and an insulating layer. The storage ferromagnetic layer includes a CoFeB sub-layer coupled to a CoFe sub-layer and/or a NiFe sub-layer through a non-magnetic sub-layer. The insulating layer is disposed between the reference and storage ferromagnetic layers. | 12-05-2013 |
20140010006 | NON-REVERSIBLE STATE AT A BITCELL HAVING A FIRST MAGNETIC TUNNEL JUNCTION AND A SECOND MAGNETIC TUNNEL JUNCTION - A memory device includes a magnetic tunnel junction (MTJ) bitcell. The MTJ bitcell includes a first MTJ and a second MTJ. The memory device further includes programming circuitry configured to generate a non-reversible state at the bitcell by applying a program signal to a selected one of the first MTJ and the second MTJ of the bitcell. The non-reversible state corresponds to a value of the MTJ bitcell that is determined by comparing a first value read at the first MTJ and a second value read at the second MTJ. | 01-09-2014 |
20140015077 | REDUCING SOURCE LOADING EFFECT IN SPIN TORQUE TRANSFER MAGNETORESISTIVE RANDOM ACCESS MEMORY (STT-MRAM) - A memory cell comprises a magnetic tunnel junction (MTJ) structure that includes a free layer coupled to a bit line and a pinned layer. A magnetic moment of the free layer is substantially parallel to a magnetic moment of the pinned layer in a first state and substantially antiparallel to the magnetic moment of the pinned layer in a second state. The pinned layer has a physical dimension to produce an offset magnetic field corresponding to a first switching current of the MTJ structure to enable switching between the first state and the second state when a first voltage is applied from the bit line to a source line coupled to an access transistor and a second switching current to enable switching between the second state and the first state when the first voltage is applied from the source line to the bit line. | 01-16-2014 |
20140015080 | STT MRAM MAGNETIC TUNNEL JUNCTION ARCHITECTURE AND INTEGRATION - A magnetic tunnel junction (MTJ) device for a magnetic random access memory (MRAM) includes a first conductive interconnect communicating with at least one control device and a first electrode coupling to the first conductive interconnect through a via opening formed in a dielectric passivation barrier using a first mask. The device has an MTJ stack for storing data, coupled to the first electrode. A portion of the MTJ stack has lateral dimensions based upon a second mask. The portion defined by the second mask is over the contact via. A second electrode is coupled to the MTJ stack and also has a lateral dimension defined by the second mask. The first electrode and a portion of the MTJ stack are defined by a third mask. A second conductive interconnect is coupled to the second electrode and at least one other control device. | 01-16-2014 |
20140035075 | MAGNETIC TUNNEL JUNCTION DEVICE - A magnetic tunnel junction device includes a Synthetic Anti-Ferromagnetic (SAF) layer, a first free layer, and second free layer. The magnetic tunnel junction device further includes a spacer layer between the first and second free layers. The first free layer is magneto-statically coupled to the second free layer. A thickness of the spacer layer is at least 4 Angstroms. | 02-06-2014 |
20140038312 | FABRICATION OF A MAGNETIC TUNNEL JUNCTION DEVICE - A magnetic tunneling junction device and fabrication method is disclosed. In a particular embodiment, a non-transitory computer-readable medium includes processor executable instructions. The instructions, when executed by a processor, cause the processor to initiate deposition of a capping material on a free layer of a magnetic tunneling junction structure to form a capping layer. The instructions, when executed by the processor, cause the processor to initiate oxidization of a first layer of the capping material to form a first oxidized layer of oxidized material. | 02-06-2014 |
20140043890 | MONOLITHIC MULTI-CHANNEL ADAPTABLE STT-MRAM - A monolithic multi-channel resistive memory includes at least one first bank associated with a first channel and tuned according to first device attributes and/or first circuit attributes. The memory also includes at least one second bank associated with a second channel and tuned according to second device attributes and/or second circuit attributes. | 02-13-2014 |
20140043924 | CONFIGURABLE MEMORY ARRAY - Embodiments disclosed include a memory array having a plurality of bit lines and a plurality of source lines disposed in columns. A plurality of word lines is disposed in rows. A plurality of storage elements have a first subset of storage elements electrically decoupled from the memory array and a second subset of storage elements coupled to the memory array. The memory array further includes a plurality of bit cells, each including one storage element from the second subset of storage elements coupled to at least two transistors. The bit cells are coupled to the plurality of bit lines and the plurality source lines. Each transistor is coupled to one word line. The memory array can further include logic to select a high performance mode and a high density mode. | 02-13-2014 |
20140047184 | TUNABLE MULTI-TIERED STT-MRAM CACHE FOR MULTI-CORE PROCESSORS - A multi-core processor is presented. The multi-core processor includes a first spin transfer torque magnetoresistive random-access memory (STT-MRAM) cache associated with a first core of the multi-core processor and tuned according to first attributes and a second STT-MRAM cache associated with a second core of the multi-core processor and tuned according to second attributes. | 02-13-2014 |
20140048894 | MTP MTJ DEVICE - Systems and methods for multiple-time programmable (MTP) devices. An MTP device includes a magnetic tunnel junction (MTJ) device programmable to a plurality of states based on voltage applied across the MTJ device. The plurality of states include a first resistance state corresponding to a first binary value stored in the MTJ device based on a first voltage, a second resistance state corresponding to a second binary value stored in the MTJ device based on a second voltage, a third resistance state corresponding to a breakdown of a barrier layer of the MTJ device based on a third voltage, and a fourth resistance state corresponding to an open fuse based on a fourth voltage. | 02-20-2014 |
20140063933 | ASYMMETRIC WRITE SCHEME FOR MAGNETIC BIT CELL ELEMENTS - A first write driver applies a first voltage above a fixed potential to a first terminal. A second write driver applies a second voltage that is higher above the fixed potential than the first voltage to a second terminal. There is at least one magnetic tunnel junction (MTJ) structure coupled at the first terminal at a first side to the first write driver and coupled at the second terminal at a second side to the second write driver. The first side of the MTJ structure receives the first voltage and the second side of the MTJ structure receives a ground voltage to change from a first state to a second state. The second side of the MTJ structure receives the second voltage and the first side of the MTJ structure receives the ground voltage to change from the second state to the first state. | 03-06-2014 |
20140067890 | MAGNETIC TUNNEL JUNCTION BASED RANDOM NUMBER GENERATOR - Embodiments of the disclosure are directed to generating a random number. An embodiment of the disclosure passes a current from a read operation through a magnetic tunnel junction (MTJ) to cause a first magnetization orientation of a free layer to switch to a second magnetization orientation, the switch in magnetization orientation causing a change in a resistance of the MTJ, and periodically samples the resistance of the MTJ to generate a bit value for the random number. | 03-06-2014 |
20140073064 | MAGNETIC TUNNEL JUNCTION (MTJ) ON PLANARIZED ELECTRODE - A magnetic tunnel junction (MTJ) with direct contact is manufactured having lower resistances, improved yield, and simpler fabrication. The lower resistances improve both read and write processes in the MTJ. The MTJ layers are deposited on a bottom electrode aligned with the bottom metal. An etch stop layer may be deposited adjacent to the bottom metal to prevent overetch of an insulator surrounding the bottom metal. The bottom electrode is planarized before deposition of the MTJ layers to provide a substantially flat surface. Additionally, an underlayer may be deposited on the bottom electrode before the MTJ layers to promote desired characteristics of the MTJ. | 03-13-2014 |
20140098602 | METHOD AND APPARATUS OF PROBABILISTIC PROGRAMMING MULTI-LEVEL MEMORY IN CLUSTER STATES OF BI-STABLE ELEMENTS - A probabilistic programming current is injected into a cluster of bi-stable probabilistic switching elements, the probabilistic programming current having parameters set to result in a less than unity probability of any given bi-stable switching element switching, and a resistance of the cluster of bi-stable switching elements is detected. The probabilistic programming current is injected and the resistance of the cluster state detected until a termination condition is met. Optionally the termination condition is detecting the resistance of the cluster of bi-stable switching elements at a value representing a multi-bit data. | 04-10-2014 |
20140108478 | MAGNETIC TUNNEL JUNCTION BASED RANDOM NUMBER GENERATOR - A random number generator system that utilizes a magnetic tunnel junction (MTJ) that is controlled by an STT-MTJ entropy controller that determines whether to proceed with generating random numbers or not by monitoring the health of the MTJ-based random number generator is illustrated. If the health of the random number generation is above a threshold, the STT-MTJ entropy controller shuts down the MTJ-based random number generator and sends a message to a requesting chipset that a secure key generation is not possible. If the health of the random number generation is below a threshold, the entropy controller allows the MTJ-based random number generator to generate random numbers based on a specified algorithm, the output of which is post processed and used by a cryptographic-quality deterministic random bit generator to generate a security key for a requesting chipset. | 04-17-2014 |
20140126284 | MRAM SENSING WITH MAGNETICALLY ANNEALED REFERENCE CELL - Systems and method for reading/sensing data stored in magnetoresistive random access memory (MRAM) cells using magnetically annealed reference cells. A MRAM includes a reference circuit comprising at least one magnetic storage cell, wherein each magnetic storage cell in the MRAM is programmed to the same state. The reference circuit includes a load element coupled to the magnetic storage cell, wherein the load element is configured to establish a reference voltage during a read operation. | 05-08-2014 |
20140147941 | MRAM DEVICE AND INTEGRATION TECHNIQUES COMPATIBLE WITH LOGIC INTEGRATION - A semiconductor device includes a magnetic tunnel junction (MTJ) storage element configured to be disposed in a common interlayer metal dielectric (IMD) layer with a logic element. Cap layers separate the common IMD layer from a top and bottom IMD layer. Top and bottom electrodes are coupled to the MTJ storage element. Metal connections to the electrodes are formed in the top and bottom IMD layers respectively through vias in the separating cap layers. Alternatively, the separating cap layers are recessed and the bottom electrodes are embedded, such that direct contact to metal connections in the bottom IMD layer is established. Metal connections to the top electrode in the common IMD layer are enabled by isolating the metal connections from the MTJ storage elements with metal islands and isolating caps. | 05-29-2014 |
20140203381 | PROCESS AND APPARATUS FOR TRANSFORMING NITRIDATION/OXIDATION AT EDGES, AND PROTECTING EDGES OF MAGNETORESISTIVE TUNNEL JUNCTION (MTJ) LAYERS - Material surrounding a magnetic tunnel junction (MTJ) device region of a multi-layer starting structure is etched, forming an MTJ device pillar having an MTJ layer with a chemically damaged peripheral edge region. De-nitridation or de-oxidation, or both, restore the chemically damaged peripheral region to form an edge-restored MTJ layer. An MTJ edge restoration assist layer is formed on the edge-restored MTJ layer. An MTJ-edge-protect layer is formed on the insulating MTJ-edge-restoration-assist layer. | 07-24-2014 |
20140206104 | STRAIN INDUCED REDUCTION OF SWITCHING CURRENT IN SPIN-TRANSFER TORQUE SWITCHING DEVICES - Partial perpendicular magnetic anisotropy (PPMA) type magnetic random access memory cells are constructed using processes and structural configurations that induce a directed static strain/stress on an MTJ to increase the perpendicular magnetic anisotropy. Consequently, reduced switching current of the MTJ results. The directed static strain/stress on the MTJ is induced in a controlled direction and/or with a controlled magnitude during fabrication. The MTJ is permanently subject to a predetermined directed stress and permanently includes the directed static strain/strain that provides reduced switching current. | 07-24-2014 |
20140210021 | METHOD AND APPARATUS FOR AMELIORATING PERIPHERAL EDGE DAMAGE IN MAGNETORESISTIVE TUNNEL JUNCTION (MTJ) DEVICE FERROMAGNETIC LAYERS - An in-process magnetic layer having an in-process area dimension is formed with a chemically damaged region at a periphery. At least a portion of the chemically damaged region is transformed to a chemically modified peripheral portion that is non-ferromagnetic. Optionally, the transforming is by oxidation, nitridation or fluorination, or combinations of the same. | 07-31-2014 |
20140219015 | SYSTEM AND METHOD OF PROGRAMMING A MEMORY CELL - A method includes creating a breakdown condition at a semiconductor transistor structure that includes an overlap region and a channel region. The breakdown condition is created by causing a first voltage difference between a gate of the semiconductor transistor structure and the overlap region to exceed a breakdown voltage of the semiconductor transistor structure while maintaining a second voltage difference between the gate and the channel region at less than the breakdown voltage. | 08-07-2014 |
20150019147 | METHOD AND DEVICE FOR ESTIMATING DAMAGE TO MAGNETIC TUNNEL JUNCTION (MTJ) ELEMENTS - For first and second magnetic tunnel junction (MTJ) elements, a trend in a relationship between an electrical characteristic of the first and second MTJ elements and an area of the first and second MTJ elements may be determined. Damage to a sidewall of the first and second MTJ elements may be estimated from the trend. At least one operating parameter of an MTJ manufacturing apparatus may be modified based on an X or Y intercept a trend line. | 01-15-2015 |
20150070979 | PHYSICALLY UNCLONABLE FUNCTION BASED ON PROGRAMMING VOLTAGE OF MAGNETORESISTIVE RANDOM-ACCESS MEMORY - One feature pertains to a method of implementing a physically unclonable function. The method includes initializing an array of magnetoresistive random-access memory (MRAM) cells to a first logical state, where each of the MRAM cells have a random transition voltage that is greater than a first voltage and less than a second voltage. The transition voltage represents a voltage level that causes the MRAM cells to transition from the first logical state to a second logical state. The method further includes applying a programming signal voltage to each of the MRAM cells of the array to cause at least a portion of the MRAM cells of the array to randomly change state from the first logical state to the second logical state, where the programming signal voltage is greater than the first voltage and less than the second voltage. | 03-12-2015 |
20150071430 | PHYSICALLY UNCLONABLE FUNCTION BASED ON THE INITIAL LOGICAL STATE OF MAGNETORESISTIVE RANDOM-ACCESS MEMORY - One feature pertains to a method for implementing a physically unclonable function (PUF). The method includes providing an array of magnetoresistive random access memory (MRAM) cells, where the MRAM cells are each configured to represent one of a first logical state and a second logical state. The array of MRAM cells are un-annealed and free from exposure to an external magnetic field oriented in a direction configured to initialize the MRAM cells to a single logical state of the first and second logical states. Consequently, each MRAM cell has a random initial logical state of the first and second logical states. The method further includes sending a challenge to the MRAM cell array that reads logical states of select MRAM cells of the array, and obtaining a response to the challenge from the MRAM cell array that includes the logical states of the selected MRAM cells of the array. | 03-12-2015 |
20150071431 | PHYSICALLY UNCLONABLE FUNCTION BASED ON THE RANDOM LOGICAL STATE OF MAGNETORESISTIVE RANDOM-ACCESS MEMORY - One feature pertains to a method of implementing a physically unclonable function (PUF). The method includes exposing an array of magnetoresistive random access memory (MRAM) cells to an orthogonal external magnetic field. The MRAM cells are each configured to represent one of a first logical state and a second logical state, and the orthogonal external magnetic field is oriented in an orthogonal direction to an easy axis of a free layer of the MRAM cells to place the MRAM cells in a neutral logical state that is not the first logical state or the second logical state. The method further includes removing the orthogonal external magnetic field to place each of the MRAM cells of the array randomly in either the first logical state or the second logical state. | 03-12-2015 |
20150071432 | PHYSICALLY UNCLONABLE FUNCTION BASED ON RESISTIVITY OF MAGNETORESISTIVE RANDOM-ACCESS MEMORY MAGNETIC TUNNEL JUNCTIONS - One feature pertains to least one physically unclonable function based on an array of magnetoresistive random-access memory (MRAM) cells. A challenge to the array of MRAM cells may identify some of the cells to be used for the physically unclonable function. Each MRAM cell may include a plurality of magnetic tunnel junctions (MTJs), where the MTJs may exhibit distinct resistances due to manufacturing or fabrication variations. A response to the challenge may be obtained for each cell by using the resistance(s) of one or both of the MTJs for a cell to obtain a value that serves as the response for that cell. The responses for a plurality of cells may be at least partially mapped to provide a unique identifier for the array. The responses generated from the array of cells may serve as a physically unclonable function that may be used to uniquely identify an electronic device. | 03-12-2015 |
20150074433 | PHYSICALLY UNCLONABLE FUNCTION BASED ON BREAKDOWN VOLTAGE OF METAL- INSULATOR-METAL DEVICE - One feature pertains to a method of implementing a physically unclonable function that includes providing an array of metal-insulator-metal (MIM) devices, where the MIM devices are configured to represent a first resistance state or a second resistance state and a plurality of the MIM devices are initially at the first resistance state. The MIM devices have a random breakdown voltage that is greater than a first voltage and less than a second voltage, where the breakdown voltage represents a voltage that causes the MIM devices to transition from the first resistance state to the second resistance state. The method further includes applying a signal line voltage to the MIM devices to cause a portion of the MIM devices to randomly breakdown and transition from the first resistance state to the second resistance state, the signal line voltage greater than the first voltage and less than the second voltage. | 03-12-2015 |