# US 11,999,614 B2 · Ferroelectric thin film > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,999,614 B2 - Document ID: US11999614B2 - Status: Granted - Kind: B2 - Application number: 18/151,810 - Filed: 2023-01-09 - Published: 2023-12-14 - Granted: 2024-06-04 - Earliest claimed: 2022-06-10 - Assignees: Korea Advanced Institute of Science and Technology; Research & Business Foundation Sungkyunkwan University - Applicants: Korea Advanced Institute of Science and Technology; Research & Business Foundation Sungkyunkwan University - Inventors: Heejun Yang; Eunji Hwang; Yonas Assefa Eshete - Web page: https://patentgrep.com/patent/US11999614B2 ## CPC - C01B 19/002: {Compounds containing, besides selenium or tellurium, more than one other element, with -O- and -OH not being considered as anions} - B32B 15/01: all layers being exclusively metallic {(making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00)} - H01B 1/06: mainly consisting of other non-metallic substances - B32B 2307/302: Conductive - C01P 2002/76: by a space-group or by other symmetry indications - C01P 2002/77: by unit-cell parameters, atom positions or structure diagrams - C01P 2006/32: Thermal properties - C01P 2006/40: Electric properties - C01P 2006/42: Magnetic properties - H10D 1/68: Capacitors having no potential barriers - H10D 30/701: {IGFETs having ferroelectric gate insulators, e.g. ferroelectric FETs} - H10D 62/882: {Graphene} - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract Provided is a thin film including Mo1-xWxTe2 stacked in a plurality of layers. The thin film has a thickness of about 1 nm to about 100 nm in a stacking direction, has a symmetric lattice structure at a temperature higher than a threshold temperature, and has an asymmetric lattice structure at a temperature equal to or lower than the threshold temperature. ## Claims ### Claim 1 An electronic device comprising: a thin film material layer including a first surface and a second surface opposing each other; an upper electrode on the first surface of the thin film material layer; a lower electrode on the second surface of the thin film material layer; and a channel layer between the thin film material layer and the upper electrode, wherein the thin film material layer includes Mo1-xWxTe2 stacked in a plurality of layers, where x is at least 0.4 and less than 1, the Mo1-xWxTe2 has a thickness of about 1 nm to about 100 nm in a stacking direction, the Mo1-xWxTe2 has a symmetric lattice structure at a temperature higher than a threshold temperature, the Mo1-xWxTe2 has an asymmetric lattice structure at a temperature equal to or lower than the threshold temperature, and the upper electrode includes a pair of electrodes connected to the channel layer. ### Claim 2 (depends on 1) The electronic device of claim 1, wherein the thin film material layer has conductivity at the temperature higher than the threshold temperature. ### Claim 3 (depends on 1) The electronic device of claim 1, wherein the Mo1-xWxTe2 has a monoclinic structure at the temperature higher than the threshold temperature. ### Claim 4 (depends on 1) The electronic device of claim 1, wherein the Mo1-xWxTe2 has ferroelectricity at the temperature equal to or lower than the threshold temperature. ### Claim 5 (depends on 4) The electronic device of claim 4, wherein a degree of polarization increases as the temperature equal to or lower than the threshold temperature decreases when x is constant. ### Claim 6 (depends on 1) The electronic device of claim 1, wherein the Mo1-xWxTe2 has an orthorhombic structure at the temperature equal to or lower than the threshold temperature. ### Claim 7 (depends on 1) The electronic device of claim 1, wherein the threshold temperature is at least 300 K. ### Claim 8 (depends on 1) The electronic device of claim 1, wherein the threshold temperature varies when x changes in the Mo1-xWxTe2. ### Claim 9 (depends on 8) The electronic device of claim 8, wherein x is 0.5 or less, and the threshold temperature increases as x increases. ### Claim 10 A electronic device comprising: a thin film material layer including a first surface and a second surface opposing each other; an upper electrode on the first surface of the thin film material layer; a lower electrode on the second surface of the thin film material layer; and a channel layer between the thin film material layer and the upper electrode, wherein the thin film material layer includes Mo1-xWxTe2 stacked in a plurality of layers, where x is at least 0.4 and less than 1, the Mo1-xWxTe2 has a thickness of about 1 nm to about 100 nm in a stacking direction, the Mo1-xWxTe2 has ferroelectricity at a temperature equal to or lower than a threshold temperature, the Mo1-xWxTe2 has a degree of polarization which increases as the temperature equal to or lower than the threshold temperature decreases when x is constant, and the upper electrode includes a pair of electrodes connected to the channel layer. ### Claim 11 (depends on 10) The electronic device of claim 10, wherein the threshold temperature varies when a value of x changes in the Mo1-xWxTe2. ### Claim 12 (depends on 11) The electronic device of claim 11, wherein x is 0.5 or less, and the threshold temperature increases as x increases. ### Claim 13 (depends on 10) The electronic device of claim 10, wherein the Mo1-xWxTe2 has a symmetric lattice structure at a temperature higher than the threshold temperature. ### Claim 14 (depends on 13) The electronic device of claim 13, wherein the Mo1-xWxTe2 has a monoclinic structure at the temperature higher than the threshold temperature. ### Claim 15 (depends on 10) The electronic device of claim 10, wherein the Mo1-xWxTe2 has an asymmetric lattice structure at the temperature equal to or lower than the threshold temperature. ### Claim 16 (depends on 15) The electronic device of claim 15, wherein the Mo1-xWxTe2 has an orthorhombic structure at the temperature equal to or lower than the threshold temperature. ### Claim 17 (depends on 10) The electronic device of claim 10, wherein the threshold temperature is at least 300 K. ### Claim 18 (depends on 10) The electronic device of claim 10, wherein resistance of the thin film material layer increases as temperature increases. ### Claim 19 An electronic device comprising: a thin film material layer including a first surface and a second surface opposing each other; an upper electrode on the first surface of the thin film material layer; and a lower electrode on the second surface of the thin film material layer, wherein the thin film material layer includes Mo1-xWxTe2 stacked in a plurality of layers, where x is at least 0.4 and less than 1, the Mo1-xWxTe2 has a thickness of about 1 nm to about 100 nm in a stacking direction, the Mo1-xWxTe2 has a symmetric lattice structure at a temperature higher than a threshold temperature, the Mo1-xWxTe2 has an asymmetric lattice structure at a temperature equal to or lower than the threshold temperature, and the upper electrode and the lower electrode comprise graphite.