# US 9,872,624 B2 · Strain sensing element, pressure sensor, microphone, blood pressure sensor, and touch panel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,872,624 B2 - Document ID: US9872624B2 - Status: Granted - Kind: B2 - Application number: 14/471,694 - Filed: 2014-08-28 - Published: 2015-03-26 - Granted: 2018-01-23 - Earliest claimed: 2013-09-20 - Assignees: Kabushiki Kaisha Toshiba - Applicants: Kabushiki Kaisha Toshiba - Inventors: Yoshihiko Fuji; Hideaki Fukuzawa; Shiori Kaji; Akio Hori; Tomohiko Nagata; Michiko Hara; Yoshihiro Higashi; Akiko Yuzawa - Web page: https://patentgrep.com/patent/US9872624B2 ## CPC - A61B 5/02141: {Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits (A61B5/02233, A61B5/0235 take precedence)} - G01L 1/125: {by using magnetostrictive means (magnetostrictive sensors H10N35/101)} - G01L 9/0041: {Transmitting or indicating the displacement of flexible diaphragms} - G01L 9/16: by making use of variations in the magnetic properties of material resulting from the application of stress - A61B 5/6824: {Arm or wrist} - A61B 2562/0247: Pressure sensors - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) ## Abstract According to one embodiment, a strain sensing element is provided on a film unit configured to be deformed. The strain sensing element includes a functional layer, a first magnetic layer, a second magnetic layer, and a spacer layer. The functional layer includes at least one of an oxide and a nitride. The second magnetic layer is provided between the functional layer and the first magnetic layer. A magnetization of the second magnetic layer is variable in accordance with a deformation of the film unit. The spacer layer is provided between the first magnetic layer and the second magnetic layer. At least a part of the second magnetic layer is amorphous and includes boron. ## Claims ### Claim 1 A strain sensing element provided on a film being deformable, the strain sensing element comprising: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one selected from the group consisting of an oxide and a nitride; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron. ### Claim 2 (depends on 1) The element according to claim 1, wherein the oxide includes an oxide of at least one selected from the group consisting of magnesium, aluminum, silicon, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, silver, hafnium, tantalum, tungsten, tin, cadmium, and gallium, and the nitride includes a nitride of at least one selected from the group consisting of magnesium, aluminum, silicon, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, silver, hafnium, tantalum, tungsten, tin, cadmium, and gallium. ### Claim 3 (depends on 1) The element according to claim 1, wherein the functional layer includes an oxide of at least one selected from the group consisting of magnesium, titanium, vanadium, zinc, tin, cadmium, and gallium. ### Claim 4 (depends on 1) The element according to claim 1, wherein the functional layer includes magnesium oxide. ### Claim 5 (depends on 1) The element according to claim 1, wherein a thickness of the functional layer is not more than one nanometer. ### Claim 6 (depends on 1) The element according to claim 1, wherein a concentration of boron included in the functional layer is not less than 5 atomic percent and not more than 35 atomic percent. ### Claim 7 (depends on 1) The element according to claim 1, wherein the second magnetic layer includes a first portion and a second portion, the first portion is provided between the second portion and the spacer layer, and a concentration of boron in the first portion is lower than a concentration of boron in the second portion. ### Claim 8 (depends on 1) The element according to claim 1, wherein the second magnetic layer includes a first portion and a second portion, the first portion is provided between the second portion and the spacer layer, and the first portion has crystallinity. ### Claim 9 (depends on 1) The element according to claim 1, wherein a magnetostriction constant of the second magnetic layer is not less than 1×10−5. ### Claim 10 (depends on 1) The element according to claim 1, wherein a coercivity of the second magnetic layer is not more than 5 oersteds. ### Claim 11 (depends on 1) The element according to claim 1, wherein a sheet resistivity of the functional layer is lower than a sheet resistivity of the spacer layer. ### Claim 12 A pressure sensor comprising: a film being deformable; and a strain sensing element provided on the film, the strain sensing element including: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one selected from the group consisting of an oxide and a nitride; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron. ### Claim 13 (depends on 12) The sensor according to claim 12, wherein the strain sensing element is provided in a plurality. ### Claim 14 (depends on 12) The sensor according to claim 12, wherein at least two of the plurality of strain sensing elements are electrically connected in series. ### Claim 15 (depends on 14) The sensor according to claim 14, wherein a voltage of not less than 1 V and not more than 10 V is applied between terminals of the strain sensing elements electrically connected in series. ### Claim 16 (depends on 14) The sensor according to claim 14, wherein a number of strain sensing elements electrically connected in series is not less than 6 and not more than 200. ### Claim 17 A strain sensing element provided on a film being deformable, the strain sensing element comprising: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one element selected from the group consisting of magnesium, silicon, and aluminum; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron. ### Claim 18 A microphone comprising: a pressure sensor, the pressure sensor including: a film being deformable; and a strain sensing element provided on the film, the strain sensing element including: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one selected from the group consisting of an oxide and a nitride; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron. ### Claim 19 A blood pressure sensor comprising: a pressure sensor, the pressure sensor including: a film being deformable; and a strain sensing element provided on the film, the strain sensing element including: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one selected from the group consisting of an oxide and a nitride; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron. ### Claim 20 A touch panel comprising: a pressure sensor, the pressure sensor including: a film being deformable; and a strain sensing element provided on the film, the strain sensing element including: a non-magnetic layer; a first magnetic layer; a functional layer provided between the non-magnetic layer and the first magnetic layer, the functional layer contacting the non-magnetic layer, the functional layer including at least one selected from the group consisting of an oxide and a nitride; a second magnetic layer provided between the functional layer and the first magnetic layer, a magnetization of the second magnetic layer being variable in accordance with a deformation of the film; and a spacer layer provided between the first magnetic layer and the second magnetic layer, at least a part of the second magnetic layer being amorphous and including boron.