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

• US 10,444,085 B2
• Filed: 12/27/2018
• Issued: 10/15/2019
• Est. Priority Date: 09/20/2013
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kaji, Shiori, Fukuzawa, Hideaki, Fuji, Yoshihiko
• Primary Examiner(s): Hollington, Octavia
• Application Number:
  US16/234,123
• Publication Number:
  US 20190128752A1
• Time in Patent Office: Days
• Field of Search: 73777, 73779, 7386269
• CPC Class Codes: G01L 1/12 by measuring variations in the magnetic properties of materials resulting from the application of stress
• CPC Class Codes: G01L 1/125 by using magnetostrictive means magnetostrictive sensors H10N35/101
• CPC Class Codes: G01L 9/16 by making use of variations in the magnetic properties of material resulting from the application of stress

Abstract

The disclosure relates to a strain sensing element provided on a deformable substrate. The strain sensing element includes: a first magnetic layer; a second magnetic layer; and an intermediate layer. The second magnetic layer includes Fe_1−yB_y (0<y≤0.3). Magnetization of the second magnetic layer changes according to deformation of the substrate. The intermediate layer is provided between the first magnetic layer and the second magnetic layer.

Claims

1. A strain sensing element fixed to a deformable substrate, the element comprising:

a first magnetic layer;

a second magnetic layer; and

an intermediate layer provided between the first magnetic layer and the second magnetic layer,

the second magnetic layer including a first part including Fe and B, and a second part including Fe, Co and B, the second part being provided between the first part and the intermediate region.

2. The element according to claim 1, wherein

the first part including Fe₁₋

yB_y (0<

y≤

0.3), and

the second part including (Fe_aCo<sub>1−

a</sub>)<sub>1−

y</sub>B_y (0.5≤

a<

1, and 0<

y≤

0.3).

3. The element according to claim 1, wherein the first part is amorphous and the second part is not amorphous.

4. The element according to claim 1, wherein the second part is provided in a region including an interface between the second magnetic layer and the intermediate layer, the region being in the second magnetic layer.

5. The element according to claim 1, wherein a thickness of the first part is larger than a thickness of the second part.

6. The element according to claim 1, wherein a thickness of the second part is 2 nm or more and 12 nm or less.

7. The element according to claim 1, further comprising

a layer including MgO, the second magnetic layer being provided between the intermediate layer and the layer including MgO.

8. The element according to claim 1, wherein the second part includes Co₄₀Fe₄₀B₂₀.

9. The element according to claim 1, wherein

the first magnetic layer includes Fe₁₋

yB_y (0<

y≤

0.3).

10. The element according to claim 1 wherein

the first magnetic layer includes (Fe_aCo₁₋

a)<sub>1−

y</sub>B_y (0.5≤

a<

1, and 0<

y≤

0.3).