Magnetoresistive random access memory cell with independently operating read and write components

摘要

A new class of the memory cell is proposed. There are two separated pulse data writing and sensing current paths. The in-plane pulse current is used to flip the magnetization direction of the perpendicular-anisotropy data storage layer sandwiched between a heavy metal writing current-carrying layer and a dielectric layer. The magnetization state within data storage layer is detected by the patterned perpendicular-anisotropy tunneling magnetoresistive (TMR) stack via the output potential of the stack. Two detailed memory cells are proposed: in one proposed cell, the data storage layer is independent from but kept close to the sensing TMR stack, whose magnetization orientation affects magnetization configuration within the free layer of the TMR stack, therefor ultimately affects the output potential of the stack; in the other proposed cell, the perpendicular-anisotropy data storage layer is the free layer of the sensing TMR stack, whose magnetization state will directly affect the output potential of the stack when sensing current passes through.

主权项

1. A memory cell comprising:
a. At least a perpendicular magnetic data storage layer, sandwiched between a non-magnetic heavy metal layer and a dielectric layer, wherein said storage layer's magnetization direction is switchable between up-pointing and down-pointing by an in-plane pulsed writing current in the non-magnetic heavy metal layer; b. At least a permanent magnet close to said data storage layer to provide an in-plane bias field to the data storage layer; and c. At least a patterned tunneling magnetoresistive stack, which is electrically independent from writing for sensing the magnetization orientation in said data storage layer.