Everspin Technologies, Inc.

Three bridge circuits ( 101, 111, 121 ), each include magnetoresistive sensors coupled as a Wheatstone bridge ( 100 ) to sense a magnetic field ( 160 ) in three orthogonal directions ( 110, 120, 130 ) that are set with a single pinning material deposition and bulk wafer setting procedure. One of the three bridge circuits ( 121 ) includes a first magnetoresistive sensor ( 141 ) comprising a first sensing element ( 122 ) disposed on a pinned layer ( 126 ), the first sensing element ( 122 ) having first and second edges and first and second sides, and a first flux guide ( 132 ) disposed non-parallel to the first side of the substrate and having an end that is proximate to the first edge and on the first side of the first sensing element ( 122 ). An optional second flux guide ( 136 ) may be disposed non-parallel to the first side of the substrate and having an end that is proximate to the second edge and the second side of the first sensing element ( 122 ).

The present disclosure is drawn to, among other things, a configuration bit including at least four resistive elements and a voltage amplifier. At least two first resistive elements may be electrically connected in series via a first electrode and at least two second resistive elements may be electrically connected in series via a second electrode. The at least two first resistive elements may be electrically connected in parallel to the at least two second resistive elements via a third electrode and a fourth electrode. The first electrode and the second electrode may be electrically connected to a voltage supply. The third electrode and the fourth electrode may be electrically connected to an input of the voltage amplifier.

A method of manufacturing a magnetoresistive device may comprise forming a first magnetic region, an intermediate region, and a second magnetic region of a magnetoresistive stack above a via; removing at least a portion of the second magnetic region using a first etch; removing at least a portion of the intermediate region and at least a portion of the first magnetic region using a second etch; removing at least a portion of material redeposited on the magnetoresistive stack using a third etch; and rendering at least a portion of the redeposited material remaining on the magnetoresistive stack electrically non-conductive.

Aspects of the present disclosure are directed to magnetic tunnel junction (MTJ) structures comprising multiple MTJ bits connected in series. For example, a magnetic tunnel junction (MTJ) stack according to the present disclosure may include at least a first MTJ bit and a second MTJ bit stacked above the first MTJ bit, and a resistance state of the MTJ stack may be read by passing a single read current through both the first MTJ bit and the second MTJ bit.

The present disclosure is drawn to, among other things, a storage device. The storage device may include a magnetic tunnel junction (MTJ)-based storage array and a communication interface. The MTJ-based storage array may be configured to be damaged by a shorting voltage based on detection of a tamper event.

Magnetoresistive device architectures and methods for manufacturing are presented that facilitate integration of process steps associated with forming such devices into standard process flows used for surrounding logic/circuitry. In some embodiments, the magnetoresistive device structures are designed such that the devices are able to fit within the vertical dimensions of the integrated circuit associated with a single metal layer and a single layer of interlayer dielectric material. Integrating the processing for the magnetoresistive devices can include using the same standard interlayer dielectric material as used in the surrounding circuits on the integrated circuit as well as using standard vias to interconnect to at least one of the electrodes of the magnetoresistive devices.

A method of manufacturing an integrated circuit device comprises forming a layer of barrier material on a surface, where the surface includes interlayer dielectric and a feature of a metal layer. The method may also include forming a layer of contact material above the layer of barrier material. The method may further include removing a portion of the layer of barrier material and a portion of the layer of contact material to form a via. Additionally, the method may include depositing magnetoresistive stack above, and in contact with, the via, where a width of the magnetoresistive stack is greater than or equal to a width of the via.

The present disclosure is drawn to, among other things, a method of managing a magnetoresistive memory (MRAM) device. In some aspects, the method includes receiving a configuration bit from a write mode configuration register. In response to determining the configuration bit is a first value, the MRAM device is operated in a NOR emulation mode. In response to determining the configuration bit is a second value, the MRAM device is operated in a persistent memory mode.

The present disclosure is drawn to, among other things, a method of managing a memory device. In some aspects, the method includes receiving data to be stored in a storage memory, wherein the storage memory is coupled to the memory device, wherein the memory device includes a first memory type and a second memory type different from the first memory type; storing a first copy of the received data in the first memory type; storing a second copy of the received data in the second memory type; receiving indication of a power loss to the memory device; in response to receiving indication of the power loss, copying the second copy from the second memory type to the storage memory; detecting for power restoration to the memory device after the power loss; and in response to detecting power restoration to the memory device, restoring data to the first memory type by copying data from the second memory type to the first memory type.

A chopping technique, and associated structure, is implemented to cancel the magnetic 1/f noise contribution in a Tunneling Magnetoresistance (TMR) field sensor. The TMR field sensor includes a first bridge circuit including multiple TMR elements to sense a magnetic field and a second circuit to apply a bipolar current pulse adjacent to each TMR element. The current lines are serially or sequentially connected to a current source to receive the bipolar current pulse. The field sensor has an output including a high output and a low output in response to the bipolar pulse. This asymmetric response allows a chopping technique for 1/f noise reduction in the field sensor.