Systems involving spin-transfer magnetic random access memory

• US 7,505,308 B1
• Filed: 05/09/2008
• Issued: 03/17/2009
• Est. Priority Date: 05/09/2008
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Lam, Chung H., Assefa, Solomon, Gallagher, William J., Sun, Jonathan Z.
• Primary Examiner(s): HUR, JUNG H
• Application Number:
  US12/118,441
• Time in Patent Office: 312 Days
• Field of Search: 365/158, 365/171, 365/173, 365/243.5, 365/225.5, 365/51, 365/230.07, 257/414, 257/421, 360/324, 360/324.1, 360/314, 360/316
• US Class Current: 365/158
• CPC Class Codes: G11C 11/16 using elements in which the storage effect is based on magnetic spin effect
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: G11C 11/1659 Cell access
• CPC Class Codes: G11C 11/1673 Reading or sensing circuits or methods
• CPC Class Codes: G11C 11/1675 Writing or programming circuits or methods

Abstract

An exemplary magnetic random access memory system comprising, a spin-current generating portion including, a ferromagnetic film layer, and a conductance layer, a first write portion in electrical contact with the ferromagnetic film including, a selection device, and a first read portion in electrical contact with the conductance layer including, a free layer magnet, a read non-magnetic layer, and a reference layer, a second write portion in electrical contact with the ferromagnetic film, and a second read portion in electrical contact with the conductance layer.

Claims

1. A magnetic random access memory system comprising:

a spin-current generating portion including;

a ferromagnetic film layer; and

a conductance layer;

a first write portion in electrical contact with the ferromagnetic film including a selection device;

a first read portion in electrical contact with the conductance layer including;

a free layer magnet;

a read non-magnetic layer; and

a reference layer;

a second write portion in electrical contact with the ferromagnetic film; and

a second read portion in electrical contact with the conductance layer.

2. The system of claim 1, further comprising a tunnel barrier layer disposed between the ferromagnetic film layer and the conductance layer.