Unlock instant, AI-driven research and patent intelligence for your innovation.

Methods and devices for determining writing current for memory cells

A technology of storage unit and storage device, which is applied in the direction of information storage, static memory, digital memory information, etc., and can solve problems such as difficulty in correct selection

Inactive Publication Date: 2006-10-18
TAIWAN SEMICON MFG CO LTD
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0018] Regardless of using the above-mentioned star selection module or other selection modules, it is difficult to select correctly because of the independent electrical or magnetic characteristics of each memory cell in the manufacturing process.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Methods and devices for determining writing current for memory cells
  • Methods and devices for determining writing current for memory cells
  • Methods and devices for determining writing current for memory cells

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0048] Figure 4 is the MTJ memory cell structure showing the MRAM device. A single memory cell includes a first operating line 41 , an MTJ memory cell 40 and a second operating line 45 . The MTJ memory cell 40 includes a fixed ferromagnetic layer 42 , an insulating tunnel barrier 43 , and a free ferromagnetic layer 44 . The insulating tunneling barrier 43 is located between the fixed ferromagnetic layer 42 and the free ferromagnetic layer 44 . The fixed ferromagnetic layer 42 is in contact with the first operation wire 41 . Here, the material of the first operating wire 41 and the second operating wire 45 can be metal, alloy, metal mixture, silicon or silicide, and the first operating wire 41 can be electrically connected to the MTJ memory unit 40 or separate.

[0049] The fixed ferromagnetic layer 42 and the free ferromagnetic layer 44 can be formed of ferromagnetic materials, and the material of the insulating tunnel barrier 43 can be an insulating material. The thickn...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

Methods for determining writing current for memory cells. A first reference current is applied to a first operative line to switch the memory cell to a first state. A second reference current is applied to a second operative line crossing the first operative line to switch the memory cell to a second state. A first writing current is obtained according to a first ratio and the first reference current. A second writing current is obtained according to a second ratio and the second reference current. The memory cell is programmed by applying the first writing current to the first operative line and applying the second writing current to the second operative line.

Description

technical field [0001] The present invention relates to a magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), in particular to a method and device for judging the writing current of an MRAM unit. Background technique [0002] The MRAM cell is usually a magnetic tunnel junction (MTJ) cell. Basically, the MTJ structure can be composed of three basic layers, namely a free ferromagnetic layer, an insulating tunneling barrier, and a pinned ferromagnetic layer. In the free ferromagnetic layer, its magnetic moment (magnetic moment) rotates with the external magnetic field, while the magnetic moment of the fixed ferromagnetic layer maintains a fixed direction. The fixed ferromagnetic layer may include a ferromagnetic layer and / or an anti-ferromagnetic layer. The anti-ferromagnetic layer can fix the magnetic moment of the fixed ferromagnetic layer in a predetermined direction. The insulating tunneling barrier consists of a very thin insulating layer...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G11C7/16G11C7/00
CPCG11C11/16G11C7/12G11C8/08G11C29/021G11C29/028
Inventor 宋弘政徐德训
Owner TAIWAN SEMICON MFG CO LTD