Abstract: Techniques and circuits for testing and configuring bias voltage or bias current for write operations in memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation.

Abstract: Techniques and circuits for testing and configuring bias voltage or bias current for write operations in memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation.

Abstract: Techniques and circuits for testing and configuring bias voltage or bias current for write operations in memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation.

Abstract: Techniques and circuits for testing and configuring magnetic memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation. Examples include adjustment of bias voltages, sense amplifier offset values, and timing parameters to improve the efficiency of testing operations as well as improve reliability and speed of normal operation.

Abstract: Techniques and circuits for testing and configuring magnetic memory devices are presented. Registers and nonvolatile storage is included on the memory devices for storing values used to control testing of the memory devices as well as for configuring parameters related to both testing and normal operation. Examples include adjustment of bias voltages, sense amplifier offset values, and timing parameters to improve the efficiency of testing operations as well as improve reliability and speed of normal operation.

Abstract: Methods and apparatus are provided for testing a magnetoresistive random access memory (MRAM). A magnetoresistive tunnel junction (MTJ) has a first terminal, a second terminal, and a third terminal. A source measuring unit is coupled to a first terminal of a MTJ to provide DC biasing. A current preamp has an input coupled to a third terminal of the MTJ for receiving current corresponding to a resistance of the MTJ. A pulse generator is AC coupled to the MTJ for programming the MTJ. A method of insitu testing a MTJ in a manufacturing environment uses a probe station coupled to the MTJ. A probe station couples to the MTJ. The MTJ is DC biased for generating a current corresponding to the logic level stored in the MTJ. A pulse for programming the MTJ is AC coupled to the MTJ.

Abstract: A method is provided for testing magnetic bits (3, 104, 514) of an array. A train of first (702), second (704), and third (706) pulses is provided to a desired bit, the first and second pulses beginning at a substantially similar low field and increasing in similar amounts with respect to successive trains of the first, second, and third pulses, the third pulse having a current amplitude sufficient to toggle the magnetic bit. A representative count is recorded in response to switching of the bit. The above steps are repeated and a determination is made of the current amplitude required to write and toggle the bit.

Abstract: A method for fabricating a cladded conductor (42) for use in a magnetoelectronics device is provided. The method includes providing a substrate (10) and forming a conductive barrier layer (12) overlying the substrate (10). A dielectric layer (16) is formed overlying the conductive barrier layer (12) and a conducting line (20) is formed within a portion of the dielectric layer (16). The dielectric layer (16) is removed and a flux concentrator (30) is formed overlying the conducting line (20).

Abstract: An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element (10) including a first electrode (14), a second electrode (18) and a spacer layer (16). The first electrode (14) and the second electrode (18) include ferromagnetic layers (26 & 28). A spacer layer (16) is located between the ferromagnetic layer (26) of the first electrode (14) and the ferromagnetic layer (28) of the second electrode (16) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers (26 & 28). The device includes insulative veils (34) characterized as electrically isolating the first electrode (14) and the second electrode (18), the insulative veils (34) including non-magnetic and insulating dielectric properties.

Abstract: Methods and apparatus are provided for testing a magnetoresistive random access memory (MRAM). A magnetoresistive tunnel junction (MTJ) has a first terminal, a second terminal, and a third terminal. A source measuring unit is coupled to a first terminal of a MTJ to provide DC biasing. A current preamp has an input coupled to a third terminal of the MTJ for receiving current corresponding to a resistance of the MTJ. A pulse generator is AC coupled to the MTJ for programming the MTJ. A method of insitu testing a MTJ in a manufacturing environment uses a probe station coupled to the MTJ. A probe station couples to the MTJ. The MTJ is DC biased for generating a current corresponding to the logic level stored in the MTJ. A pulse for programming the MTJ is AC coupled to the MTJ.

Abstract: A reduced power method of writing MRAM bits is disclosed. The reduced power method includes writing MRAM bits by applying a first magnetic field having a low magnitude, then determining if the bit has switched. If not, a second magnetic field having a higher magnitude is applied. Applying magnetic fields to an MRAM bit cell is accomplished by sending a current pulse through a strip line adjacent to the MRAM bit cell. The technique can be performed for every write to an MRAM bit. Alternatively, the weaker magnetic field can be applied during system test or system initialization, and if the weaker field fails to write the bit to a desired value, the failing result is stored and each subsequent write to the MRAM bit utilizes the stronger magnetic field.

Abstract: A method for fabricating an MRAM device structure includes providing a substrate on which is formed a first transistor and a second transistor. An operative memory element device is formed in electrical contact with the first transistor. At least a portion of a false memory element device is formed in electrical contact with the second transistor. A first dielectric layer is deposited overlying the at least a portion of a false memory element device and the operative memory element device. The first dielectric layer is etched to simultaneously form a first via to the at least a portion of a false memory element device and a second via to the operative memory element device. An electrically conductive interconnect layer is deposited so the electrically conductive interconnect layer extends from the at least a portion of a false memory element device to the operative memory element device.

Abstract: An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element (10) including a first electrode (14), a second electrode (18) and a spacer layer (16). The first electrode (14) and the second electrode (18) include ferromagnetic layers (26 & 28). A spacer layer (16) is located between the ferromagnetic layer (26) of the first electrode (14) and the ferromagnetic layer (28) of the second electrode (16) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers (26 & 28). The device includes insulative veils (34) characterized as electrically isolating the first electrode (14) and the second electrode (18), the insulative veils (34) including non-magnetic and insulating dielectric properties.

Abstract: A method for fabricating an MRAM device structure includes providing a substrate on which is formed a first transistor and a second transistor. An operative memory element device is formed in electrical contact with the first transistor. At least a portion of a false memory element device is formed in electrical contact with the second transistor. A first dielectric layer is deposited overlying the at least a portion of a false memory element device and the operative memory element device. The first dielectric layer is etched to simultaneously form a first via to the at least a portion of a false memory element device and a second via to the operative memory element device. An electrically conductive interconnect layer is deposited so the electrically conductive interconnect layer extends from the at least a portion of a false memory element device to the operative memory element device.

Abstract: An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element (10) including a first electrode (14), a second electrode (18) and a spacer layer (16). The first electrode (14) and the second electrode (18) include ferromagnetic layers (26 & 28). A spacer layer (16) is located between the ferromagnetic layer (26) of the first electrode (14) and the ferromagnetic layer (28) of the second electrode (16) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers (26 & 28). The device includes insulative veils (34) characterized as electrically isolating the first electrode (14) and the second electrode (18), the insulative veils (34) including non-magnetic and insulating dielectric properties.

Abstract: A method for fabricating an MRAM device structure includes providing a substrate on which is formed a first transistor and a second transistor. An operative memory element device is formed in electrical contact with the first transistor. At least a portion of a false memory element device is formed in electrical contact with the second transistor. A first dielectric layer is deposited overlying the at least a portion of a false memory element device and the operative memory element device. The first dielectric layer is etched to simultaneously form a first via to the at least a portion of a false memory element device and a second via to the operative memory element device. An electrically conductive interconnect layer is deposited so the electrically conductive interconnect layer extends from the at least a portion of a false memory element device to the operative memory element device.

Abstract: An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element (10) including a first electrode (14), a second electrode (18) and a spacer layer (16). The first electrode (14) and the second electrode (18) include ferromagnetic layers (26 & 28). A spacer layer (16) is located between the ferromagnetic layer (26) of the first electrode (14) and the ferromagnetic layer (28) of the second electrode (16) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers (26 & 28). The device includes insulative veils (34) characterized as electrically isolating the first electrode (14) and the second electrode (18), the insulative veils (34) including non-magnetic and insulating dielectric properties.

Abstract: An MTJ cell including an insulator layer of material between magnetic material layers with the insulator layer of material having a greater attraction for a third material than the magnetic material layers. The third material is introduced to one or both so that when the cell is heated the third material is redistributed from the magnetic material layer to the insulator layer. Upon redistribution the insulator layer becomes an insulator layer material. Also, a first diffusion barrier layer is positioned between a first metal electrode and one of the magnetic material layers and/or a second diffusion barrier layer is positioned between a second metal electrode and the other magnetic material layer to prevent diffusion of the metal in the electrodes into the magnetic material layers.

Abstract: A method of fabricating an MRAM cell includes providing an isolation transistor on a semiconductor substrate and forming an interconnect stack on the substrate in communication with one terminal of the transistor. A via is formed on the upper end of the stack so as to extend from a position below the digit line to a position above the digit line. The via also extends above the upper surface of a dielectric layer to provide an alignment key. A MTJ memory cell is positioned on the upper surface in contact with the via, and the ends of a free layer of magnetic material are spaced from the ends of a pinned edge of magnetic material by using sidewall spacers and selective etching.

Abstract: Magnetic tunnel junction random access memory architecture in which an array of memory cells is arranged in rows and columns and each memory cell includes a magnetic tunnel junction and a control transistor connected in parallel. A control line is connected to the gate of each control transistor in a row of control transistors and a metal programming line extending adjacent to each magnetic tunnel junction is connected to the control line in spaced apart intervals by vias. Further, groups of memory cells in each column are connected in series to form local bit lines which are connected in parallel to global bit lines. The series-parallel configuration is read using a centrally located column to provide a reference signal and data from columns on each side of the reference column is compared to the reference signal or two columns in proximity are differentially compared.