Title:
MRAM及びMRAMの書き込み方法
Document Type and Number:
Japanese Patent JP4386158
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a write system and its element structure which enables the write current margin to be increased for writing in an MRAM. SOLUTION: Memory cells having magnetic tunnel junctions (MTJ) including a reversible magnetization free ferromagnetic layer 4a, a magnetization- nonrevervible fixed ferromagnetic layer 4b, and an insulation film 5 disposed therebetween are connected to mutually approximately orthogonally crossing upper and lower wirings 9, 12. Write-only wiring 11 is provided in approximately parallel to the lower wiring. A current component (vertical current) flowing from the upper wiring to the lower wiring via the MTJ generates an annular internal magnetic field in the magnetic layer to make the domain structure of the magnetic layer unstable, and then a current flowing on the write-only wiring induces a magnetic field which reverses the magnetization of the magnetic layer to write. The intensity of the vertical current is adjusted to reduce external magnetic fields, thereby increasing a write margin.
Inventors:
Honda Yuji
Noboru Sakimura
Naohiko Sugibayashi
Noboru Sakimura
Naohiko Sugibayashi
Application Number:
JP2001325855A
Publication Date:
December 16, 2009
Filing Date:
October 24, 2001
Export Citation:
Assignee:
NEC
International Classes:
G11C11/14; H01L21/8246; G11C11/15; H01L27/105; H01L43/08
Domestic Patent References:
| JP2003092440A | ||||
| JP2002118306A | ||||
| JP2001084758A | ||||
| JP2001156357A | ||||
| JP2001519582A |
Attorney, Agent or Firm:
Keiji Miyamoto