# US 12,004,324 B2 · Metallic thermal interface materials and associated devices, systems, and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,324 B2 - Document ID: US12004324B2 - Status: Granted - Kind: B2 - Application number: 17/879,630 - Filed: 2022-08-02 - Published: 2023-12-21 - Granted: 2024-06-04 - Earliest claimed: 2022-06-21 - Assignees: Deeia Inc. - Applicants: Deeia Inc. - Inventors: Himanshu Pokharna - Web page: https://patentgrep.com/patent/US12004324B2 ## CPC - H05K 7/2029: {using a liquid coolant with phase change in electronic enclosures (in cabinets of standardized dimensions H05K7/20536; in server cabinets H05K7/20709; in vehicle electronic casings H05K7/20845; in power control electronics H05K7/2089; in displays H05K7/20954)} - H05K 7/20409: {Outer radiating structures on heat dissipating housings, e.g. fins integrated with the housing} - H05K 7/20509: {Multiple-component heat spreaders; Multi-component heat-conducting support plates; Multi-component non-closed heat-conducting structures} - H10W 40/43: by flowing gases, e.g. forced air cooling - G06F 1/20: Cooling means - G06F 2200/201: Cooling arrangements using cooling fluid - H01M 10/613: Cooling or keeping cold - H01M 10/653: characterised by electrically insulating or thermally conductive materials - H01M 10/6551: Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings - H01M 10/659: by heat storage or buffering, e.g. heat capacity or liquid-solid phase changes or transition - H10W 40/73: for cooling by change of state - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY ## Abstract A heat-transfer component defines a thermal-interface surface and has a metallic thermal-interface material bonded to the thermal-interface surface. The metallic thermal-interface material has a solid-to-liquid phase-change temperature between about 60° C. and about 90° C. With a thermal-interface material bonded to the thermal-interface surface, the thermal-contact resistance between the thermal-interface material and the heat-transfer component can be reduced or substantially eliminated compared to conventional thermal-interface materials, including conventional metallic thermal-interface materials. Also disclosed are electrical devices having a heat generating component cooled by such a heat-transfer component. ## Claims ### Claim 1 An integrated heat-spreader configured to overlie an integrated-circuit die, the integrated heat-spreader comprising: a first major surface defining a thermal-interface surface and being configured to face a heat-removal device; a second major surface positioned opposite the thermal-interface surface and being configured to face the integrated-circuit die; and a metallic thermal-interface material bonded to the thermal-interface surface, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C, wherein the metallic thermal-interface material is a eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 2 (depends on 1) The integrated heat-spreader according to claim 1, wherein the solid-to-liquid transition temperature is about 60° C., about 70° C., about 80° C., or about 90° C. ### Claim 3 An integrated heat-spreader configured to overlie an integrated-circuit die, the integrated heat-spreader comprising: a first major surface defining a thermal-interface surface and being configured to face a heat-removal device; a second major surface positioned opposite the thermal-interface surface and being configured to face the integrated-circuit die; and a metallic thermal-interface material bonded to the thermal-interface surface, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C., wherein the metallic thermal-interface material is a non-eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 4 (depends on 3) The integrated heat-spreader according to claim 3, wherein the solid-to-liquid transition temperature is about 90° C. ### Claim 5 (depends on 4) The integrated heat-spreader according to claim 4, wherein the metallic thermal-interface material has a liquid-to-solid transition temperature of about 70° C. ### Claim 6 (depends on 3) The integrated heat-spreader according to claim 3, wherein the solid-to-liquid transition temperature is less than about 90° C. and the liquid-to-solid transition temperature is above about 70° C. ### Claim 7 A heat-removal device configured to dissipate heat received from a heat-generating electronic component, the heat-removal device comprising: a base defining a first major surface and a second major surface opposite the first major surface; a metallic thermal-interface material bonded to the first major surface, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C., wherein the metallic thermal-interface material is a eutectic mixture of Bismuth, Indium, Tin and Gallium; and a plurality of fins extending from the second major surface. ### Claim 8 (depends on 7) The heat-removal device according to claim 7, wherein the solid-to-liquid transition temperature is about 60° C., about 70° C., about 80° C., or about 90° C. ### Claim 9 An electrical device, comprising: a heat-generating component defining a first thermal-interface surface; an integrated heat spreader configured to overlie the heat-generating component, the integrated heat spreader defining a first major surface and a second major surface positioned opposite the first major surface, the first major surface being configured to face a heat-removal device and the second major surface being configured to face the heat-generating component; and a metallic thermal-interface material bonded to the second major surface of the integrated heat spreader, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C.; wherein the metallic thermal-interface material is a eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 10 (depends on 9) The electrical device according to claim 9, wherein the solid-to-liquid transition temperature is about 60° C., about 70° C., about 80° C., or about 90° C. ### Claim 11 (depends on 9) The electrical device according to claim 9, wherein the heat-generating component is an electronic processing unit. ### Claim 12 (depends on 9) The electrical device according to claim 9, wherein the heat-generating component is an electrical storage battery. ### Claim 13 An electrical device, comprising: a heat-generating component defining a first thermal-interface surface; a heat-removal device configured to dissipate heat received from the heat-generating electronic component, the heat-removal device having a base defining a first major surface and further defining a second major surface opposite the first major surface, wherein a plurality of fins extends from the second major surface of the heat-removal device, and wherein a metallic thermal-interface material is bonded to the first major surface of the base, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C.; wherein the metallic thermal-interface material is a eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 14 (depends on 13) The electrical device according to claim 13, wherein the solid-to-liquid transition temperature is about 60° C., about 70° C., about 80° C., or about 90° C. ### Claim 15 (depends on 13) The electrical device according to claim 13, wherein the heat-generating component is an electronic processing unit. ### Claim 16 (depends on 13) The electrical device according to claim 13, wherein the heat-generating component is an electrical storage battery. ### Claim 17 A heat-removal device configured to dissipate heat received from a heat-generating electronic component, the heat-removal device comprising: a base defining a first major surface and a second major surface opposite the first major surface; a metallic thermal-interface material bonded to the first major surface, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C., wherein the metallic thermal-interface material is a non-eutectic mixture of Bismuth, Indium, Tin and Gallium; and a plurality of fins extending from the second major surface. ### Claim 18 (depends on 17) The heat-removal device according to claim 17, wherein the solid-to-liquid transition temperature is about 90° C. ### Claim 19 (depends on 18) The heat-removal device according to claim 18, wherein the metallic thermal-interface material has a liquid-to-solid transition temperature of about 70° C. ### Claim 20 (depends on 17) The heat-removal device according to claim 17, wherein the solid-to-liquid transition temperature is less than about 90° C. and the liquid-to-solid transition temperature is above about 70° C. ### Claim 21 An electrical device, comprising: a heat-generating component defining a first thermal-interface surface; an integrated heat spreader configured to overlie the heat-generating component, the integrated heat spreader defining a first major surface and a second major surface positioned opposite the first major surface, the first major surface being configured to face a heat-removal device and the second major surface being configured to face the heat-generating component; and a metallic thermal-interface material bonded to the second major surface of the integrated heat spreader, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C.; wherein the metallic thermal-interface material is a non-eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 22 (depends on 21) The electrical device according to claim 21, wherein the heat-generating component is an electronic processing unit. ### Claim 23 (depends on 21) The electrical device according to claim 21, wherein the heat-generating component is an electrical storage battery. ### Claim 24 (depends on 21) The electrical device according to claim 21, wherein the solid-to-liquid transition temperature is about 90° C. ### Claim 25 (depends on 24) The electrical device according to claim 24, wherein the metallic thermal-interface material has a liquid-to-solid transition temperature of about 70° C. ### Claim 26 (depends on 21) The electrical device according to claim 21, wherein the solidus-to-liquidus transition temperature is less than about 90° C. and the liquidus-to-solidus transition temperature is above about 70° C. ### Claim 27 An electrical device, comprising: a heat-generating component defining a first thermal-interface surface; a heat-removal device configured to dissipate heat received from the heat-generating electronic component, the heat-removal device having a base defining a first major surface and further defining a second major surface opposite the first major surface, wherein a plurality of fins extends from the second major surface of the heat-removal device, and wherein a metallic thermal-interface material is bonded to the first major surface of the base, the metallic thermal-interface material having a solid-to-liquid transition temperature between about 60° C. and about 90° C.; wherein the metallic thermal-interface material is a non-eutectic mixture of Bismuth, Indium, Tin and Gallium. ### Claim 28 (depends on 27) The electrical device according to claim 27, wherein the heat-generating component is an electronic processing unit. ### Claim 29 (depends on 27) The electrical device according to claim 27, wherein the heat-generating component is an electrical storage battery. ### Claim 30 (depends on 27) The electrical device according to claim 27, wherein the solid-to-liquid transition temperature is about 90° C. ### Claim 31 (depends on 30) The electrical device according to claim 30, wherein the metallic thermal-interface material has a liquid-to-solid transition temperature of about 70° C. ### Claim 32 (depends on 27) The electrical device according to claim 27, where solid-to-liquid transition temperature is less than about 90° C. and the liquid-to-solid transition temperature is above about 70° C.