# US 12,765,276 B2 · Switch based on phase-change material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,765,276 B2 - Document ID: US12765276B2 - Status: Granted - Kind: B2 - Application number: 18/190,901 - Filed: 2023-03-27 - Published: 2024-01-18 - Granted: 2026-10-13 - Earliest claimed: 2022-07-18 - Assignees: Commissariat A L'energie Atomique Et Aux Energies Alternatives; STMicroelectronics (Crolles 2) SAS; STMicroelectronics France - Applicants: Commissariat A L'energie Atomique Et Aux Energies Alternatives; STMicroelectronics (Crolles 2) SAS; STMicroelectronics France - Inventors: Alain Fleury; Stephane Monfray; Philippe Cathelin; Bruno Reig; Vincent Puyal - Web page: https://patentgrep.com/patent/US12765276B2 ## CPC - H10N 70/823: {adapted for essentially horizontal current flow, e.g. bridge type devices} - H10N 70/011: {Manufacture or treatment of multistable switching devices} - H10N 70/063: {by etching of pre-deposited switching material layers, e.g. lithography} - H10N 70/231: {based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect} - H10N 70/253: {having three or more electrodes, e.g. transistor-like devices} - H10N 70/841: {Electrodes} - H10N 70/8413: {adapted for resistive heating} - H10N 70/861: {Thermal details} - H10N 70/8613: {Heating or cooling means other than resistive heating electrodes, e.g. heater in parallel} - H10N 70/8828: {Tellurides, e.g. GeSbTe} - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract The present description concerns a switch based on a phase-change material comprising: a region of the phase-change material; a heating element electrically insulated from the region of the phase-change material; and one or a plurality of pillars extending in the region of the phase-change material, the pillar(s) being made of a material having a thermal conductivity greater than that of the phase-change material. ## Claims ### Claim 1 A device, comprising: a switch that includes a phase-change material, the switch including: first and second conduction electrodes; first and second regions of the phase-change material each coupled to the first and second conduction electrodes of the switch, the second region being located above the first region; and a heating element between the first and second regions of the phase-change material and electrically insulated from the first and second regions of the phase-change material; and a first plurality of pillars extending in the first region of the phase-change material, the first plurality of pillars being made of a material having a thermal conductivity greater than that of the phase-change material. ### Claim 2 (depends on 1) The device according to claim 1, wherein the first region is on top of and in contact with the first and second electrodes. ### Claim 3 (depends on 2) The device according to claim 2, wherein the second region is coupled to the first and second electrodes by vias. ### Claim 4 (depends on 3) The device according to claim 3, wherein the vias are in contact, by respective upper surfaces, with a lower surface of the second region of the phase-change material. ### Claim 5 (depends on 2) The device according to claim 2, wherein the second region of the phase-change material is under and in contact with third and fourth electrodes. ### Claim 6 (depends on 5) The device according to claim 5, wherein the third and fourth electrodes are respectively coupled to the first and second electrodes by vias. ### Claim 7 (depends on 1) The device according to claim 1, wherein the heating element is tungsten. ### Claim 8 (depends on 1) The device according to claim 1, comprising a second plurality of pillars extending in the second region of the phase-change material, the second plurality of pillars being made of the material having the thermal conductivity greater than that of the phase-change material. ### Claim 9 A device, comprising: a substrate; a first and second electrode on the substrate; a first phase change layer on the first and second electrode; a heating element on the first phase change layer; a second phase change layer on the heating element, the heating element being between the first and second phase change layers; and a plurality of pillars extending in the first phase change layer, the pillars being made of a material having a thermal conductivity greater than that of the first phase change layer. ### Claim 10 (depends on 9) The device of claim 9, comprising a third and fourth electrode on the second phase change layer. ### Claim 11 (depends on 10) The device of claim 10, comprising a first via between the third electrode and the first electrode. ### Claim 12 (depends on 11) The device of claim 11, comprising a second via between the fourth electrode and the second electrode. ### Claim 13 A method, comprising; forming a first and a second electrode on a substrate; forming a first phase change layer on the first and second electrodes; forming a heating element on the first phase change layer; forming a second phase change layer on the heating element, the heating element being between the first and second phase change layers; forming a first insulating layer on the first phase change layer; and forming a second insulating layer on the first insulating layer, on the first electrode, and on the second electrode. ### Claim 14 (depends on 13) The method of claim 13, wherein the forming the first and second electrodes includes forming the first electrode spaced from the second electrode by a dimension and forming the first phase change layer overlapping the first electrode, the second electrode, and completely over the dimension between the first and second electrodes. ### Claim 15 (depends on 13) The method of claim 13, comprising forming a third electrode and a fourth electrode on the second phase change layer. ### Claim 16 (depends on 15) The method of claim 15, comprising forming a first via coupling the third electrode to the first electrode and forming a second via coupling the fourth electrode to the second electrode. ### Claim 17 (depends on 13) The method of claim 13, comprising forming a plurality of pillars extending in the first phase change layer. ### Claim 18 (depends on 17) The method of claim 17, wherein the plurality of pillars includes a first material having a thermal conductivity greater than a second material of the first phase change layer. ### Claim 19 (depends on 18) The method of claim 18, wherein both the first phase change layer and the second phase change layer include the second material. ### Claim 20 (depends on 13) The method of claim 13, comprising forming a passivation layer on the first phase change layer.