Magnetic-assisted nondestructive self-reference sensing method for spin-transfer torque random access memory

摘要

A method of reading a memory cell of a magneto-resistive random access memory device, wherein the memory cell has a ferromagnetic free layer having a first magnetization orientation and a ferromagnetic reference layer, includes applying a first read current from the ferromagnetic free layer to the ferromagnetic reference layer and storing a first voltage generated by the memory cell in response to the first read current, generating a magnetic field adjacent to the memory cell, the magnetic field having a second magnetization orientation that is not parallel to the first magnetization orientation, while the magnetic field is being generated, applying a second read current from the ferromagnetic free layer to the ferromagnetic reference layer and storing a second voltage generated by the memory cell in response to the second read current, and determining a state of the memory cell based on the first voltage and the second voltage.

主权项

1. A method of reading a memory cell of a magneto-resistive random access memory device, the memory cell having a ferromagnetic free layer having a first magnetization orientation and a ferromagnetic reference layer, comprising:
applying a first read current from the ferromagnetic free layer to the ferromagnetic reference layer and storing a first voltage generated by the memory cell in response to the first read current; generating a magnetic field adjacent to the memory cell, the magnetic field having a second magnetization orientation that is not parallel to the first magnetization orientation; while the magnetic field is being generated, applying a second read current from the ferromagnetic free layer to the ferromagnetic reference layer and storing a second voltage generated by the memory cell in response to the second read current; terminating the magnetic field after the second voltage is stored; and determining a state of the memory cell based on the first voltage and the second voltage.