Strain detection element, pressure sensor, microphone, blood pressure sensor, and touch panel

Patent metadata

Field	Value
Publication number	US-10048150-B2
Application number	US-201514755633-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Jul 2, 2014
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

A strain detection element is provided above a deformable membrane. Moreover, this strain detection element includes an electrode and a stacked body, the stacked body including: a first magnetic layer whose magnetization direction is variable according to a deformation of the membrane; a second magnetic layer provided facing the first magnetic layer; and an intermediate layer provided between these first magnetic layer and second magnetic layer, and at least part of the first magnetic layer is amorphous, and the electrode includes a metal layer configured from a Cu—Ag alloy.

First claim

What is claimed is:

1. A stacked structure comprising:
a metal layer including a Cu 1-x Ag x alloy (1 at. %≤x≤20 at. %);
a first magnetic layer;
a second magnetic layer provided between the metal layer and the first magnetic layer; and
an intermediate layer provided between the first magnetic layer and the second magnetic layer,
an electrical resistance of the strain detection element being configured to change in accordance with a strain of the membrane.

2. The stacked structure according to claim 1 , wherein a crystal grains size of the metal layer is 50 nm or less.

3. The stacked structure according to claim 1 , wherein
the intermediate layer has a first interface opposing the first magnetic layer, and
an Ra value of the first interface is 0.3 nm or less,
the Ra value is expressed by the following formulas (1) and (2),

Z
C

=

1
n

⁢

∑
i
n

⁢

Z
⁡

(
i
)

Formula
⁢

⁢

(
1
)

Ra
=

1
n

⁢

∑
i

n

⁢



Z
⁡

(
i
)

-

Z
C



Formula
⁢

⁢

(
2
)

wherein Zc is a mean value of a position of the first interface in a height direction from the metal layer toward the first magnetic layer, and Z(i) is the position of the first interface in the height direction.

4. The stacked structure according to claim 1 , wherein
the intermediate layer has a first interface opposing the first magnetic layer, and
an Rmax value of the first interface is 2.5 nm or less,
the Rmax value is expressed by the following formula (3),
R max= =max( Z ( i ))−min( Z ( i ))  Formula (3)

wherein Z(i) is a position of the first interface in a height direction from the metal layer toward the first magnetic layer, max(Z(i)) is a maximum value of Z(i), and min(Z(i)) is a minimum value of Z(i).

5. The stacked structure according to claim 1 , wherein the metal layer has a first face opposing the second magnetic layer, and
an Ra value of the first face is 2 nm or less,
the Ra value is expressed by the following formulas (1) and (2),

Z
C

=

1
n

⁢

∑
i
n

⁢

Z
⁡

(
i
)

Formula
⁢

⁢

(
1
)

Ra
=

1
n

⁢

∑
i

n

⁢



Z
⁡

(
i
)

-

Z
C



Formula
⁢

⁢

(
2
)

wherein Zc is a mean value of a position of the first face in a height direction from the metal layer toward the first magnetic layer, and Z(i) is the position of the first face in the height direction.

6. The stacked st

Assignees

• Toshiba Kk

Inventors

• Fuji Yoshihiko
• Fukuzawa Hideaki
• Hori Akio
• Kaji Shiori

Classifications

• G01L9/0042

  Constructional details associated with semiconductive diaphragm sensors, e.g. etching, or constructional details of non-semiconductive diaphragms (details about the integration or bonding of piezoresistor in or on the diaphragm G01L9/0052 and G01L9/0057 respectively) · CPC title

• G01L9/0044

  Constructional details of non-semiconductive diaphragms · CPC title

• G01L9/16 Primary

  by making use of variations in the magnetic properties of material resulting from the application of stress · CPC title

• H10N50/10

  Magnetoresistive devices · CPC title