# US 11,444,242 B2 · Resistive memory device and method of manufacturing the same and electronic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,242 B2 - Document ID: US11444242B2 - Status: Granted - Kind: B2 - Application number: 16/701,293 - Filed: 2019-12-03 - Published: 2020-11-12 - Granted: 2022-09-13 - Earliest claimed: 2019-05-08 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Kwanghee Kim; Heejae Lee; Oul Cho; Tae Hyung Kim; Eun Joo Jang - Web page: https://patentgrep.com/patent/US11444242B2 ## CPC - H10D 62/814: {Quantum box structures} - H10N 70/881: {Switching materials} - H10B 63/00: Resistance change memory devices, e.g. resistive RAM [ReRAM] devices - H10D 48/381: {Multistable devices; Devices having two or more distinct operating states} - H10N 70/021: {Formation of switching materials, e.g. deposition of layers} - H10N 70/245: {the species being metal cations, e.g. programmable metallization cells} - H10N 70/841: {Electrodes} - H10D 62/826: comprising only Group II-VI materials heterojunctions, e.g. CdTe/HgTe heterojunctions - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - H10B: ELECTRONIC MEMORY DEVICES ## Abstract A resistive memory device including a first electrode and a second electrode facing each other and a variable resistance layer disposed between the first electrode and the second electrode, wherein the variable resistance layer includes cadmium-free quantum dots (Cd-free quantum dots) and at least a portion of the Cd-free quantum dots include a Cd-free quantum dot including a halide anion on a surface of the Cd-free quantum dot, a method of manufacturing the same and an electronic device. ## Claims ### Claim 1 A resistive memory device, comprising: a first electrode and a second electrode facing each other, and a variable resistance layer disposed between the first electrode and the second electrode, wherein the variable resistance layer comprises Cd-free quantum dots, a first portion of the Cd-free quantum dots comprises a halide anion on the surface thereof, and a second portion of the Cd-free quantum dots does not comprise the halide anion on the surface thereof. ### Claim 2 (depends on 1) The resistive memory device of claim 1, wherein the halide anion is derived from a metal halide, and the metal halide comprises zinc, indium, lead, gallium, magnesium, lithium, or a combination thereof. ### Claim 3 (depends on 2) The resistive memory device of claim 2, wherein the metal halide comprises a zinc fluoride, a zinc chloride, a zinc bromide, a zinc iodide, an indium fluoride, an indium chloride, an indium bromide, an indium iodide, a lead fluoride, a lead chloride, a lead bromide, a lead iodide, a gallium fluoride, a gallium chloride, a gallium bromide, a gallium iodide, a magnesium fluoride, a magnesium chloride, a magnesium bromide, a magnesium iodide, a lithium fluoride, a lithium chloride, a lithium bromide, a lithium iodide, or a combination thereof. ### Claim 4 (depends on 1) The resistive memory device of claim 1, wherein the Cd-free quantum dots comprise zinc, indium, silver or a combination thereof. ### Claim 5 (depends on 4) The resistive memory device of claim 4, wherein the Cd-free quantum dots comprise ZnSe, ZnSeTe, InZn, InP, InZnP, or a combination thereof. ### Claim 6 (depends on 1) The resistive memory device of claim 1, wherein the Cd-free quantum dots comprise: a core comprising a first semiconductor nanocrystal, and a shell disposed on the core, the shell comprising a second semiconductor nanocrystal different from the first semiconductor nanocrystal. ### Claim 7 (depends on 6) The resistive memory device of claim 6, wherein the first semiconductor nanocrystal comprises ZnSe, ZnSeTe, InP, InZnP, or a combination thereof. ### Claim 8 (depends on 6) The resistive memory device of claim 6, wherein the second semiconductor nanocrystal comprises zinc, selenium, sulfur, or a combination thereof. ### Claim 9 (depends on 1) The resistive memory device of claim 1, wherein the Cd-free quantum dots comprise an organic ligand on the surface thereof, the organic ligand comprising RCOOH, RNH2, R2NH, R3N, RH2PO, R2HPO, R3PO, RH2P, R2HP, R3P, ROH, RCOOR, RPO(OH)2, RHPOOH, R2POOH, or a combination thereof, wherein each R is the same or different and is independently a substituted or unsubstituted C1 to C40 aliphatic hydrocarbon, a substituted or unsubstituted C6 to C20 aromatic hydrocarbon, or a combination thereof. ### Claim 10 (depends on 1) The resistive memory device of claim 1, wherein the variable resistance layer comprises: a first variable resistance layer comprising the Cd-free quantum dots comprising the halide anion on the surface thereof, and a second variable resistance layer comprising the Cd-free quantum dots not comprising the halide anion on the surface thereof. ### Claim 11 (depends on 10) The resistive memory device of claim 10, wherein the Cd-free quantum dots not comprising the halide anion on the surface thereof comprise a carboxylic acid-containing ligand. ### Claim 12 (depends on 11) The resistive memory device of claim 11, wherein the second variable resistance layer is disposed on the first variable resistance layer, and the variable resistance layer further comprises a third variable resistance layer disposed on the second variable resistance layer, the third variable resistance layer comprising the Cd-free quantum dots comprising the halide anion on the surface thereof. ### Claim 13 (depends on 1) An electronic device comprising the resistive memory device of claim 1. ### Claim 14 A method of manufacturing a resistive memory device, comprising: providing a first electrode, forming a variable resistance layer on the first electrode, and providing a second electrode on the variable resistance layer to manufacture the resistive memory device, wherein the variable resistance layer comprises Cd-free quantum dots, and a first portion of the Cd-free quantum dots comprises a halide anion on the surface thereof, and a second portion of the Cd-free quantum dots does not comprise the halide anion on the surface thereof. ### Claim 15 (depends on 14) The method of claim 14, wherein the forming of the variable resistance layer comprises preparing a dispersion comprising the Cd-free quantum dots, forming a precursor layer comprising the Cd-free quantum dots from the dispersion comprising the Cd-free quantum dots, preparing a halide solution comprising a halide and a polar solvent, and providing the halide solution to the precursor layer to convert at least one of the Cd-free quantum dots into a Cd-free quantum dot comprising the halide anion on the surface thereof. ### Claim 16 (depends on 14) The method of claim 14, wherein the forming of the variable resistance layer comprises preparing a dispersion comprising the Cd-free quantum dots, preparing a halide solution comprising a halide and a polar solvent, and mixing the dispersion comprising the Cd-free quantum dots and the halide solution to convert at least one of the Cd-free quantum dots into a Cd-free quantum dot comprising the halide anion on the surface thereof; and forming the variable resistance layer from the mixed dispersion. ### Claim 17 (depends on 16) The method of claim 16, wherein the mixing of the dispersion comprising the Cd-free quantum dots and the halide solution comprises: mixing the dispersion comprising the Cd-free quantum dots and the halide solution so that an amount of the halide is about 0.1 weight percent to about 10 weight percent, based on a total weight of the Cd-free quantum dots. ### Claim 18 (depends on 14) The method of claim 14, wherein the forming of the variable resistance layer comprises: forming a first variable resistance layer comprising the Cd-free quantum dots comprising the halide anion on the surface thereof, and forming a second variable resistance layer on the first variable resistance layer, the second variable resistance layer comprising the Cd-free quantum dots not comprising the halide anion on the surface thereof. ### Claim 19 (depends on 18) The method of claim 18, wherein the forming of the variable resistance layer further comprises forming a third variable resistance layer on the second variable resistance layer, the third variable resistance layer comprising the Cd-free quantum dots comprising the halide anion on the surface thereof. ### Claim 20 A method of manufacturing a resistive memory device, comprising: providing a first electrode, forming an auxiliary layer on the first electrode, preparing a dispersion comprising Cd-free quantum dots, preparing a halide solution comprising a halide and a polar solvent, mixing the dispersion comprising the Cd-free quantum dots and the halide solution to convert the Cd-free quantum dots into Cd-free quantum dots comprising a halide anion on the surface thereof and Cd-free quantum dots not comprising the halide anion on the surface thereof, coating the dispersion comprising the Cd-free quantum dots comprising the halide anion on the surface thereof and the Cd-free quantum dots not comprising the halide anion on the surface thereof on the auxiliary layer to form a variable resistance layer, and providing a second electrode on the variable resistance layer to manufacture the resistive memory device.