US 6,549,455 B2 · Magnetic memory device including storage element exhibiting ferromagnetic tunnel effect

Abstract

A magnetic memory device capable of preventing complication of the structure of an amplifier (sense amplifier) and enabling high-speed reading is provided. In this magnetic memory device, a memory cell is formed by a pair of first and second storage elements exhibiting a ferromagnetic tunnel effect and a pair of first and second transistors while an amplifier detects potential difference between a bit line and an inverted bit line connected to the pair of first and second storage elements. Thus, data can be readily read. Further, the value of a small current flowing to the bit line may not be detected dissimilarly to a case of forming the memory cell by a storage element exhibiting a ferromagnetic tunnel effect and a transistor. Consequently, the structure of the amplifier is not complicated. Further, no amplifier having a complicated structure may be employed, whereby high-speed reading is enabled.

Claims24

Dependent claims

A magnetic memory device comprising:

a memory cell consisting of a first storage element and a second storage element exhibiting a ferromagnetic tunnel effect and first and second transistors connected to said first and second storage elements respectively;
a word line connected to control terminals of said first and second transistors;
a bit line connected to said first storage element through said first transistor;
an inverted bit line connected to said second storage element through said second transistor for forming a pair of bit lines with said bit line;
and
an amplifier connected to said bit line and said inverted bit line,
for inputting a signal in selected said word line while reading potential difference caused between said bit line and said inverted bit line by inputting said signal in said word line through said amplifier in data reading.

4 more elements

A magnetic memory device comprising:

a memory cell consisting of a storage element exhibiting a ferromagnetic tunnel effect including a first magnetic layer, a second magnetic layer having a surface opposed to a surface of said first magnetic layer through a first isolation barrier layer and a third magnetic layer opposed to another surface of said second magnetic layer through a second isolation barrier layer and first and second transistors connected to said first magnetic layer and said third magnetic layer of said storage element respectively;
a word line connected to control terminals of said first and second transistors;
a bit line connected to said first magnetic layer through said first transistor;
an inverted bit line connected to said third magnetic layer through said second transistor for forming a pair of bit lines with said bit line;
and
an amplifier connected to said bit line and said inverted bit line,
for inputting a signal in selected said word line while reading potential difference caused between said bit line and said inverted bit line by inputting said signal in said word line in data writing.

4 more elements

Dependencies are inferred from the claim text.

Magnetic memory device including storage element exhibiting ferromagnetic tunnel effect

Life of this patent

Magnetic memory device including storage element exhibiting ferromagnetic tunnel effect

Life of this patent

Abstract

Claims24