Abstract: A spin transfer torque magnetic random access memory (STTMRAM) magnetic tunnel junction (MTJ) stack includes layers to which when electric current is applied cause switching of the direction of magnetization of at least one of the layer. The STTMRAM MTJ stack includes a reference layer (RL) with a direction of magnetization that is fixed upon manufacturing of the STTMRAM MTJ stack, a junction layer (JL) formed on top of the RL, a free layer (FL) formed on top of the JL. The FL has a direction of magnetization that is switchable relative to that of the RL upon the flow of electric current through the spin transfer torque magnetic random access memory (STTMRAM) magnetic tunnel junction (MTJ) stack. The STTMRAM MTJ stack further includes a spin confinement layer (SCL) formed on top of the FL, the SCL made of ruthenium.

Abstract: The invention provides a bottom-type perpendicular magnetic tunnel junction (pMTJ) element with thermally stable amorphous blocking layers for high-density nonvolatile data storage. The first blocking layer, preferably formed of an amorphous nonmagnetic film, blocks a polycrystalline diffusion barrier layer with a body-center-cubic (bcc) <110> texture in order for the keeper and lower reference layers of the bottom-type pMTJ element to freely grow with a face-centered-cubic (fcc) <111> texture, thereby developing strong perpendicular magnetic anisotropy (PMA). The second blocking layer, preferably formed of an amorphous ferromagnetic film, blocks the keeper and lower reference layers of the bottom-type pMTJ element in order for the upper reference, barrier and storage layers of the bottom-type pMTJ element to freely grow with a <001> texture, thereby exhibiting a strong tunneling magnetoresistance (TMR) effect.

Abstract: A hybrid non-volatile memory device includes a non-volatile random access memory (NVRAM) having an array of magnetic memory elements, the NVRAM being bit-accessible. The hybrid non-volatile device further includes a non-volatile page-mode memory (PMM) made of resistive memory and organized into pages, the non-volatile PMM being page-accessible. Further included in the hybrid non-volatile memory device is a direct memory access (DMA) engine that is coupled to the NVRAM and the non-volatile PMM and transfers data between the NVRAM and the non-volatile PMM during a DMA operation.

Abstract: A block storage system includes a host and comprises a block storage module that is coupled to the host. The block storage module includes a MRAM array and a bridge controller buffer coupled to communicate with the MRAM array. The MRAM array includes a buffer widow that is moveable within the MRAM array to allow contents of the MRAM array to be read by the host through the bridge controller buffer even when the capacity of the bridge controller buffer is less than the size of the data being read from the MRAM array.

Abstract: Methods for testing magnetoresistance of test devices with layer stacks, such as MTJs, fabricated on a wafer are described. The test devices can be fabricated along with arrays of similarly structured memory cells on a production wafer to allow in-process testing. The test devices with contact pads at opposite ends of the bottom electrode allow resistance across the bottom electrode to be measured as a surrogate for measuring resistance between the top and bottom electrodes. An MTJ test device according to the invention has a measurable magnetoresistance (MR) between the two contact pads that is a function of the magnetic orientation of the free layer and varies with the length and width of the MTJ strip in each test device. The set of test MTJs can include a selected range of lengths to allow the tunnel magnetoresistance (TMR) and resistance area product (RA) to be estimated or predicted.

Abstract: A method of initializing a magnetic random access memory (MRAM) element that is configured to store a state when electric current flows therethrough is disclosed. The MRAM element includes a first magnetic tunnel junction (MTJ) for storing a data bit and a second MTJ for storing a reference bit. The direction of magnetization of the FL is determinative of the data bit stored in the at least one MTJ and each MTJ further includes a magnetic reference layer (RL) having a magnetization with a direction that is perpendicular to the film plane, and a magnetic pinned layer (PL) having a magnetization with a direction that is perpendicular to the film plane. The direction of magnetization of the RL and the PL are anti-parallel relative to each other in the first MTJ. The direction of magnetization of the FL, the RL and the PL are parallel relative to each other in the second MTJ for storing reference bit.

Abstract: A method of measuring the resistance of a magnetic tunnel junction (MTJ) is performed by selecting the MTJ to be measured, the MTJ having a resistance associated therewith and coupled to an access transistor. Further, measuring a voltage at an end of the MTJ that is coupled to the access transistor and measuring voltage, V0, at the coupling of the selected MTJ and the associated access transistor, turning off a decoder that is coupled to the MTJ, and after applying current, measuring the applied current and using the measured applied current to determine the resistance of the MTJ.

Abstract: The present invention is directed to a method for manufacturing spin transfer torque magnetic random access memory (STTMRAM) devices. The method, which utilizes in-situ annealing and etch-back of the magnetic tunnel junction (MTJ) film stack, comprises the steps of depositing a barrier layer on top of a bottom magnetic layer and then depositing an interface magnetic layer on top of the barrier layer to form an MTJ film stack; annealing the MTJ film stack at a first temperature and then cool the MTJ film stack to a second temperature lower than the first temperature; etching away a top portion of the interface magnetic layer; and depositing at least one top layer on top of the etched interface magnetic layer. The method may further include the step of annealing the MTJ film stack at a third temperature between the first and second temperature after the step of depositing at least one top layer.

Abstract: The present invention is directed to a spin transfer torque magnetic random access memory (STT-MRAM) device having a plurality of memory elements. Each of the plurality of memory elements comprises a magnetic reference layer with a first invariable magnetization direction substantially perpendicular to layer plane thereof; a magnetic free layer separated from the magnetic reference layer by an insulating tunnel junction layer with the magnetic free layer having a variable magnetization direction substantially perpendicular to layer plane thereof; a dielectric layer formed in contact with the magnetic free layer opposite the insulating tunnel junction layer; and a first conductive layer formed in contact with the dielectric layer opposite the magnetic free layer.

Abstract: A method of accessing a server address space of a shared PCIe end point system includes programming a primary address translation table with a server address of a server address space, setting up a direct memory access (DMA) to access a primary port memory map, the primary port memory map correlating with addresses in the primary address translation table, and re-directing the direct memory accesses to the primary port memory map to the server address space according to the primary address translation table.

Abstract: A testing method is described for performing a fast bit-error rate (BER) measurement on resistance-based RAM cells, such MTJ cells, at the wafer or chip level. Embodiments use one or more specially designed test memory cells fabricated with direct electrical connections between the two electrodes of the cell and external contact pads (or points) on the surface of the wafer (or chip). In the test setup the memory cell is connected an impedance mismatched transmission line through a probe for un-buffered, fast switching of the cell between the high and low resistance states without the need for CMOS logic to select and drive the cell. The unbalanced transmission line is used generate signal reflections from the cell that are a function of the resistance state. The reflected signal is used to detect whether the test cell has switched as expected.

Abstract: A magnetic memory cell is formed including a magneto tunnel junction (MTJ) and an access transistor, which is used to access the MTJ in operation. The access transistor, which is formed on a silicon substrate, includes a gate, drain and source with the gate position substantially perpendicular to the plane of the silicon substrate thereby burying the gate and allowing more surface area on the silicon substrate for formation of additional memory cells.

Abstract: Methods of fabricating MTJ arrays using two orthogonal line patterning steps are described. Embodiments are described that use a self-aligned double patterning method for one or both orthogonal line patterning steps to achieve dense arrays of MTJs with feature dimensions one half of the minimum photo lithography feature size (F). In one set of embodiments, the materials and thicknesses of the stack of layers that provide the masking function are selected so that after the initial set of mask pads have been patterned, a sequence of etching steps progressively transfers the mask pad shape through the multiple mask layer and down through all of the MTJ cell layers to the form the complete MTJ pillars. In another set of embodiments, the MTJ/BE stack is patterned into parallel lines before the top electrode layer is deposited.

Abstract: A magnetic random access memory (MRAM) array having a magnetic tunnel junction (MTJ) to be read using a magnetic state of the MTJ, the MTJ being read by applying a current there through. Further, the MRAM array has a reference MTJ, a sense amplifier coupled to the MTJ and the reference MTJ, the sense amplifier operable to compare the voltage of the MTJ to the reference MTJ in determining the state of the MTJ; a first capacitor coupled to the sense amplifier at a first end and to ground at a second end; and a second capacitor coupled to the sense amplifier at a first end and to ground at a second end, the first capacitor storing the, wherein short voltage pulses are applied to the first end of each of the first and second capacitors when reading the MTJ thereby makes the current flowing through the MTJ there through for small time intervals thereby avoiding read disturbance to the MTJ.

Abstract: BEOL memory cells are described that include one or more sidewall protection layers on the memory device (including, for example, an MTJ element) deposited prior to interconnect via etching to prevent the formation of electrical shorts between layers. One embodiment uses a single layer sidewall protection sleeve that is deposited after the memory device has been patterned. The layer material is vertically etched down to expose the upper surface of the top electrode while leaving a residual layer of protective material surrounding the rest of the memory device. The material for the protection layer is selected to resist the etchant used to remove the first dielectric material from the via in the subsequent interconnect process. A second embodiment uses dual-layer sidewall protection in which the first layer covers the memory element is preferably an oxygen-free dielectric and the second layer protects the first layer during via etching.

Abstract: BEOL memory cells are described that include one or more sidewall protection layers on the memory device (including, for example, an MTJ element) deposited prior to interconnect via etching to prevent the formation of electrical shorts between layers. One embodiment uses a single layer sidewall protection sleeve that is deposited after the memory device has been patterned. The layer material is vertically etched down to expose the upper surface of the top electrode while leaving a residual layer of protective material surrounding the rest of the memory device. The material for the protection layer is selected to resist the etchant used to remove the first dielectric material from the via in the subsequent interconnect process. A second embodiment uses dual-layer sidewall protection in which the first layer covers the memory element is preferably an oxygen-free dielectric and the second layer protects the first layer during via etching.

Abstract: A method of programming a MTJ includes selecting a MTJ that is coupled to an access transistor at the drain of the access transistor. The gate of the access transistor is coupled to a selected word line (WL), the selected WL is substantially at a first voltage, Vdd; whereas the WLs that are not coupled to the MTJ are left to float. A second voltage, Vx, is applied to the unselected bit lines (BLs) and further applied to a source line (SL), the SL being coupled to the source of the access transistor. A third voltage, Vdd or 0 Volts, is applied to a selected BL, the selected BL is coupled the MTJ. The first voltage is applied to a SL, the SL is coupled to the source of the access transistor thereby causing the WL to boot above the first voltage.

Abstract: The present invention is directed to an apparatus for initializing perpendicular magnetic tunnel junction. The apparatus comprises a permanent magnet for generating a magnetic flux; a flux concentrator made of a soft ferromagnetic material and having a base area in contact with the permanent magnet and an tip area that is smaller than the base area, thereby funneling and concentrating the magnetic flux to the tip area for emitting a magnetic field therefrom; and a means for supporting and conveying a substrate with an arrays of magnetic tunnel junctions formed therein to traverse the magnetic field in close proximity to the tip area. The apparatus may further include at least one of the following: a substrate heater, a flux containment structure coupled to the permanent magnet, and a magnetic imaging plate disposed in proximity to the substrate on the opposite side from the flux concentrator.

Abstract: A method of configuring a computer memory system includes receiving a request from customized software driver or a BIOS extension software or a customized legacy BIOS or a customized UEFI PMM extension software or a customized UEFI BIOS, scanning memory module sockets in response to the request, recognizing memory modules in the memory module sockets, the memory modules being made of, at least in part, persistent memory modules (PMMs), configuring the PMMs to be invisible to the OS, and storing the mapping information to a designated protected persistent memory area, and presenting the PMMs as a persistent block storage to the OS.

Abstract: Chip packages are described with soft-magnetic shields that are included inside or attached externally to the package containing a MRAM chip. In one group of embodiments a single shield with vias for bonding wires is affixed to the surface of the MRAM chip having the contact pads. The limitation of shield to chip distance due to bonding wire is eliminated by VIA holes according to the invention which achieves minimal spacing between the shield and chip. A second shield without vias can be positioned on the opposite side of the chip from the first shield. In one group of embodiments a hardened ferro-fluid shield can be the only shield or the structure can include a shield with or without vias. One group of embodiments includes an external shield with vias for solder access to the package contact pads affixed to the outer surface of the package.