# US 2025/0098548 A1 · Semiconductor device and method for fabricating the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0098548 A1 - Document ID: US20250098548A1 - Status: Published application - Kind: A1 - Application number: 18/584,969 - Filed: 2024-02-22 - Published: 2025-03-20 - Earliest claimed: 2023-09-19 - Assignees: SK hynix Inc. - Applicants: SK hynix Inc. - Inventors: Cha Deok DONG - Web page: https://patentgrep.com/patent/US20250098548A1 ## CPC - H10N 50/80: Constructional details - H10B 61/10: {comprising components having two electrodes, e.g. diodes or MIM elements} - H10B 63/24: {of the Ovonic threshold switching type} - H10B 63/80: {Arrangements comprising multiple bistable or multi-stable switching components of the same type on a plane parallel to the substrate, e.g. cross-point arrays} - H10N 50/01: Manufacture or treatment - H10N 50/10: Magnetoresistive devices - H10N 70/826: {adapted for essentially vertical current flow, e.g. sandwich or pillar type devices} - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - H10B: ELECTRONIC MEMORY DEVICES ## Abstract Semiconductor devices and methods for fabricating semiconductor memory devices are disclosed. In an embodiment, a semiconductor device includes: a selector pattern configured to exhibit a threshold switching behavior; an insulating layer structured to a sidewall of the selector pattern and include an opening disposed within the insulating layer over the selector pattern; and an electrode formed in the opening to a thickness that blocks an entrance of the opening and does not completely fill the opening. ## Claims ### Claim 1 A semiconductor device comprising: a selector pattern configured to exhibit a threshold switching behavior by exhibiting different electrical conducting characteristics in response to an applied voltage with respect to a threshold voltage; an insulating layer structured to surround a sidewall of the selector pattern and include an opening disposed within the insulating layer over the selector pattern; and an electrode formed in the opening to a thickness that blocks an entrance of the opening and does not completely fill the opening. ### Claim 2 (depends on 1) The semiconductor device according to claim 1, further comprising: an air gap surrounded by the electrode in the opening. ### Claim 3 (depends on 1) The semiconductor device according to claim 1, wherein the entrance of the opening has a width that is narrower than a width of a lower surface of the opening. ### Claim 4 (depends on 1) The semiconductor device according to claim 1, wherein the opening has a width that increases from the entrance of the opening to a top surface of the selector pattern. ### Claim 5 (depends on 1) The semiconductor device according to claim 1, further comprising: a buffer pattern disposed between the selector pattern and the electrode. ### Claim 6 (depends on 5) The semiconductor device according to claim 5, wherein the buffer pattern includes a material having a higher specific resistance than the electrode. ### Claim 7 (depends on 1) The semiconductor device according to claim 1, wherein the electrode and the insulating layer have a planarized upper surface. ### Claim 8 (depends on 7) The semiconductor device according to claim 7, further comprising: a magnetic tunnel junction structure formed over the planarized upper surface and electrically connected to the electrode. ### Claim 9 A method for fabricating a semiconductor device, comprising: forming a stacked structure that includes a selector pattern and a sacrificial electrode, wherein the selector pattern is configured to exhibit a threshold switching behavior by exhibiting different electrical conducting characteristics in response to an applied voltage with respect to a threshold voltage; forming an insulating layer structured to surround a sidewall of the stacked structure; forming an opening by removing at least part of the sacrificial electrode; and forming an electrode in the opening to a thickness that blocks an entrance of the opening and does not completely fill the opening. ### Claim 10 (depends on 9) The method according to claim 9, wherein an uppermost portion of the sacrificial electrode has a width that is narrower than a width of a lower surface of the opening. ### Claim 11 (depends on 9) The method according to claim 9, wherein the sacrificial electrode has a width that increases from the entrance of the opening to a top surface of the selector pattern. ### Claim 12 (depends on 9) The method according to claim 9, wherein the sacrificial electrode includes titanium nitride, and the at least part of the sacrificial electrode is removed by using hydrogen peroxide. ### Claim 13 (depends on 9) The method according to claim 9, wherein the forming of the electrode comprises: depositing a conductive material over the insulating layer with a thickness that blocks the entrance of the opening and does not completely fill the opening; and performing a planarization process to expose an upper surface of the insulating layer. ### Claim 14 (depends on 13) The method according to claim 13, wherein the electrode includes an upper surface that is planarized with the upper surface of the insulating layer, and wherein the method further comprises: forming a magnetic tunnel junction structure electrically connected to the electrode over the upper surface of the insulating layer and the upper surface of the electrode, after forming the electrode. ### Claim 15 (depends on 9) The method according to claim 9, wherein the stacked structure further includes a buffer pattern interposed between the sacrificial electrode and the selector pattern. ### Claim 16 (depends on 15) The method according to claim 15, wherein the buffer pattern includes amorphous carbon. ### Claim 17 (depends on 15) The method according to claim 15, wherein while the opening is formed, the buffer pattern is maintained. ### Claim 18 (depends on 15) The method according to claim 15, wherein while the opening is formed, at least part of the buffer pattern is removed. ### Claim 19 (depends on 18) The method according to claim 18, wherein the stacked structure further includes an additional electrode interposed between the buffer pattern and the selector pattern, and while the opening is formed, the additional electrode is maintained. ### Claim 20 (depends on 19) The method according to claim 19, wherein the electrode and the additional electrode include a same material.