SPIN-ORBIT-TORQUE MAGNETORESISTIVE RANDOM ACCESS MEMORY WITH VOLTAGE-CONTROLLED ANISOTROPY

摘要

Methods and apparatus relating to spin-orbit-torque magnetoresistive random access memory with voltage-controlled anisotropy are disclosed. In an example, disclosed is a three-terminal magnetic tunnel junction (MTJ) storage element that is programmed via a combination of voltage-controlled magnetic anisotropy (VCMA) and spin-orbit torque (SOT) techniques. Also disclosed is a memory controller configured to program the three-terminal MTJ storage element via VCMA and SOT techniques. The disclosed devices improve efficiency over conventional devices by using less write energy, while having a design that is simpler and more scalable than conventional devices. The disclosed devices also have increased thermal stability without increasing required switching current, as critical switching current between states is essentially the same.

主权项

1. A method for writing data to a three-terminal spin-orbit-torque magnetoresistive memory having a magnetoresistive tunnel junction (MTJ) including a free layer located between an oxide barrier layer and a substantially planar spin hall-effect material, comprising:
applying a first voltage across the MTJ to reduce a magnetic anisotropy of the free layer by inducing an electric field across the oxide barrier layer and reducing energy barrier for switching the free layer magnetization; and applying a second voltage across the substantially planar spin hall-effect material to cause a current to flow through the substantially planar spin hall-effect material and thereby apply a spin-orbit torque to the free layer, thus causing the free layer to switch between a parallel state and an antiparallel state.