MAGNETIC MEMORY USING SPIN CURRENT, OPERATING METHOD THEREOF, AND ELECTRONIC APPARATUS INCLUDING MAGNETIC MEMORY

Smart overview of the Invention

The patent describes a magnetic memory device that utilizes spin currents to store and retrieve data. This device comprises two intersecting wirings separated by a data storage layer. The data storage layer includes a pinned layer with a fixed magnetic moment and a free layer, which lacks a fixed magnetic moment and is separated from the pinned layer by an insulating tunnel barrier. The wiring in contact with the free layer is conductive and does not exhibit the spin Hall effect, while the free layer is made of a two-dimensional material that does exhibit this effect.

Components and Structure

The memory device's free layer consists of a two-dimensional van der Waals material, which at room temperature shows magnetic and metallic properties alongside the spin Hall effect. Examples of such materials include Fe(x)GeTe2, CrTe2, and VSe2. The device can feature multiple wirings, with each intersection hosting its own data storage layer. This layer may contain an MTJ (magnetic tunnel junction) and an insulating tunnel barrier, which could be composed of materials like MgO, boron nitride, or aluminum oxide.

Operation Method

The operation of this magnetic memory involves applying different operating currents to manipulate the spin currents within the device. A first operating current is applied to the wiring contacting the free layer, generating a spin current in the free layer. A second operating current applied to the other wiring also generates a spin current in the free layer. The second current is typically less than the first, and both currents can be used for writing or erasing data.

Switching Mechanism

The method for switching involves lowering the coercive force of the free layer using a first spin current and then switching its magnetic moment using a second spin current. This process allows for efficient data recording or erasure by manipulating the free layer's properties with precision. The wiring contacting the free layer is designed to be metal without a spin Hall effect, ensuring effective operation.

Applications

This technology can be integrated into electronic devices requiring high-speed memory solutions with enhanced durability and lower operating current density. The described SOT-MRAM (spin orbit torque-magnetic random access memory) features a cross-point lattice arrangement for efficient data storage and retrieval, separating write and read paths to improve performance and lifespan.