A magnetic tunnel junction device and its magnetic random access memory device

Abstract

The invention discloses a magnetic tunnel junction device and a magnetic random storage device thereof. The device relates to an artificial antiferromagnetic device capable of assisting the flipping of a free magnetic layer and a fixed magnetic layer. The artificial antiferromagnetic device can be regulated by an electric field , realize the transition from the antiferromagnetic state to the ferromagnetic state, and cooperate with the fixed magnetic layer to assist the flipping of the free magnetic layer. The magnetic random access memory device includes a magnetic tunnel junction, and when a current passes through the magnetic tunnel junction, the free magnetic layer is flipped under the assistance of an electric field. After the free magnetic layer is flipped, the electric field is removed, and the composite multilayer film structure returns from the ferromagnetic state to the antiferromagnetic state, while the free magnetic layer remains in the flipped state, thereby realizing data writing. The synthetic multilayer film structure and the magnetic tunnel junction together constitute a magnetic random access memory device, which achieves the purpose of writing data through the joint action of electric field and current, and has the advantages of fast speed, low power consumption, and non-volatility.

Description

technical field [0001] The invention relates to circuits and devices with magnetic / ferromagnetic materials or structures and applications thereof, more specifically, to an artificial antiferromagnet controlled by an electric field and a magnetic random access memory using it for auxiliary erasing and writing. Background technique [0002] A magnetic tunnel junction (called MTJ) is composed of two layers of magnetic metal (such as iron, cobalt, nickel) and an ultra-thin insulating layer (such as aluminum oxide, or magnesium oxide) sandwiched between the two magnetic metal layers. If a bias voltage is applied between the two magnetic metal layers, since the insulating layer is very thin, electrons can tunnel through its potential barrier. Under a given bias voltage, the size of the tunneling current / tunneling resistance depends on the relative orientation of the magnetization in the two ferromagnetic layers. This phenomenon is called tunneling magnetoresistance (TMR), which is...

AI Technical Summary

Problems solved by technology

However, the spin polarization current applied to spin-transfer torque-random memory is generally in the range of 10 6 to 10 7 A / cm 2 , a larger spin-polarized current will limit the arrangement density of the memory cell array and consume more power

Images