MRAM HAVING SPIN HALL EFFECT WRITING AND METHOD OF MAKING THE SAME

摘要

A spin-transfer-torque magnetoresistive memory comprises apparatus and method of manufacturing a three terminal magnetoresistive memory element having highly conductive bottom electrodes overlaid on top of a SHE-metal layer in the regions outside of an MTJ stack. The memory cell comprises a bit line positioned adjacent to selected ones of the plurality of magnetoresistive memory elements to supply a reading current across the magnetoresistive element stack and two highly conductive bottom electrodes overlaid and electrically contacting on top of a SHE-metal layer in the outside of an MTJ region and to supply a bi-directional spin Hall effect recording current, and accordingly to switch the magnetization of the recording layer. Thus magnetization of a recording layer can be readily switched or reversed to the direction in accordance with a direction of a current along the SHE-metal layer by applying a low write current.

主权项

1. A three terminal SHE spin transfer magnetoresistive memory comprising a control circuitry and at least one memory cell comprising:
a SHE metal layer provided on a surface of a substrate; a recording layer provided on the top surface of the SHE layer having magnetic anisotropy in a film plane and having a variable magnetization direction; a tunnel barrier layer provided on the top surface of the recording layer; a reference layer provided on the top surface of the tunnel barrier layer having magnetic anisotropy in a film plane and having an invariable magnetization direction; a cap layer provided on the top surface of the reference layer as an upper electric electrode; a first bottom electrode provided on a first side of the SHE metal layer and electrically connected to the SHE metal layer; a second bottom electrode provided on a second side of the SHE metal layer and electrically connected to the SHE metal layer; a bit line provided on the top surface of the cap layer; two CMOS transistors coupled the plurality of magnetoresistive memory elements through the two bottom electrodes. There is further provided circuitry connected to the bit line, and two select transistors of each magnetoresistive memory cell.The control circuitry coupled through the bit line and the two select transistors to selected ones of the plurality of magnetoresistive memory elements to supply a reading current across the magnetoresistive element stack and two highly conductive bottom electrodes overlaid and electrically contacting on top of a SHE-metal layer in the outside of an MTJ region and to supply a bi-directional spin Hall effect recording current, and accordingly to switch the magnetization of the recording layer.