Voltage-adjustable reluctance-variable random memory cell and random memory

Abstract

The invention proposes a voltage-adjustable magnetoresistance random access memory unit, which includes: a bottom electrode layer; a ferroelectric oxide layer formed on the bottom electrode layer; and a magnetic layer formed on the ferroelectric oxide layer, wherein , the magnetic layer and the bottom electrode layer serve as the upper and lower electrodes of the ferroelectric oxide layer respectively to apply voltage to the ferroelectric oxide layer, where the direction of the voltage is perpendicular to the ferroelectric oxide layer, and the ferroelectric oxide layer can The arrangement of the magnetic moments in the magnetic layer is controlled so that the resistance of the magnetic layer changes in the set measurement direction. The present invention also proposes a memory having the magnetoresistive random access memory unit. The invention can write information data using voltage, and has advantages such as non-volatility, low writing power consumption, and high storage density.

Description

technical field [0001] The invention relates to the technical field of random storage, in particular to a magnetoresistive variable random storage unit with adjustable voltage and a random storage unit with the storage unit. Background technique [0002] Magneto-resistive random access memory (MRAM) is considered to be one of the most promising next-generation embedded memories to be widely used because of its good durability and non-volatile storage characteristics. Its core working component is a stacked magnetoresistive random memory unit with a sandwich structure of "magnetic free layer / oxide tunneling insulating layer / magnetic pinned layer". Its working principle is that the ampere current passing through the bit line and the data line is used to generate a magnetic field, and the magnetization vector in the magnetic free layer is rotated through the magnetic field, so that the angle between the magnetization direction between the magnetic free layer and the magnetic pi...

AI Technical Summary

Problems solved by technology

The problem with MRRAM is that as the size of the memory cell shrinks, it will become increasingly difficult to generate a magnetic field through a current within the specified memory cell while ensuring that it does not have a large impact on the storage state of adjacent memory cells. The more difficult it is, this restricts the improvement of memory recording density

However, since the state is still written in the current mode, the predictable power consumption of the memory will still be higher than that of the state written in the pure voltage mode, such as flash memory (FLASH) based on semiconductor CMOS elements, ferroelectric random access memory (FeRAM) ERAM

In addition, the direction of the write current and the read current in the spin torque transfer based magnetoresistive random access memory are both perpendicular to the stacked memory cell, which increases the risk of dielectric breakdown in the tunneling insulating layer in the memory cell , which in turn affects the durability of the memory device

[0004] On the other hand, although described flash memory and ferroelectric RAM have lower power consumption, they also have their own shortcomings.

Wherein, the flash memory utilizes the charging and discharging of the semiconductor capacitive element to realize data recording, and the writing time is relatively long; the ferroelectric RAM utilizes the ferroelectric polarization direction of the ferroelectric material to realize data storage, although the writing speed is relatively fast, However, the reading method is destructive, that is, the stored data cannot be retained after the data is read.

Moreover, with the prolongation of time, the remnant polarization of the ferroelectric film in the memory gradually decreases, which will cause the memory to fail to distinguish between the two polarization states of "0" and "1".

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