# US 2025/0098151 A1 · Semiconductor device including air gap protection structure with uneven thickness and manufacturing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0098151 A1 - Document ID: US20250098151A1 - Status: Published application - Kind: A1 - Application number: 18/370,490 - Filed: 2023-09-20 - Published: 2025-03-20 - Earliest claimed: 2023-09-20 - Assignees: Nanya Technology Corporation - Applicants: Nanya Technology Corporation - Inventors: WEI-CHUAN FANG - Web page: https://patentgrep.com/patent/US20250098151A1 ## CPC - H10B 12/482: {Bit lines} - H10B 12/02: {for one transistor one-capacitor [1T-1C] memory cells} - H10B 12/0335: {Making a connection between the transistor and the capacitor, e.g. plug} - H10B 12/315: {with the capacitor higher than a bit line} - H10B: ELECTRONIC MEMORY DEVICES ## Abstract A semiconductor device and method for manufacturing the same are provided. The semiconductor device includes a substrate, a bit line, an isolation spacer, a landing pad, and air gap protection structure. The bit line is disposed on the substrate. The isolation spacer is disposed on a side of the bit line. The isolation spacer includes an air gap. The landing pad is disposed over the bit line. The air gap protection structure covers the landing pad and the air gap. The air gap protection structure has an upper portion above a top surface of the landing pad and a lower portion below the upper portion. A ratio between a thickness of the lower portion and a thickness of the upper portion is greater than 0.6 and less than 0.8. ## Claims ### Claim 1 A semiconductor device, comprising: a substrate; a bit line disposed on the substrate; an isolation spacer disposed on a side of the bit line, wherein the isolation spacer comprises an air gap; a landing pad disposed over the bit line; and an air gap protection structure covering the landing pad and the air gap, wherein the air gap protection structure has an upper portion above a top surface of the landing pad and a lower portion below the upper portion, and a ratio between a thickness of the lower portion and a thickness of the upper portion is greater than 0.6 and less than 0.8. ### Claim 2 (depends on 1) The semiconductor device of claim 1, wherein the air gap protection structure comprises silicon nitride. ### Claim 3 (depends on 2) The semiconductor device of claim 2, wherein the air gap protection structure comprises carbon. ### Claim 4 (depends on 3) The semiconductor device of claim 3, wherein an atomic ratio of carbon is greater than 4.8%. ### Claim 5 (depends on 2) The semiconductor device of claim 2, wherein the air gap protection structure comprises hydrogen. ### Claim 6 (depends on 1) The semiconductor device of claim 1, wherein a hole is defined by the landing pad and located over the air gap, and the air gap protection structure is located within the hole. ### Claim 7 (depends on 6) The semiconductor device of claim 6, wherein the hole defined by the air gap protection structure has a smaller aperture near the upper portion of the air gap protection structure and a greater aperture near the lower portion of the air gap protection structure. ### Claim 8 (depends on 6) The semiconductor device of claim 6, wherein an aspect ratio of the hole is greater than 2. ### Claim 9 (depends on 1) The semiconductor device of claim 1, further comprising: a capacitor contact spaced apart from the bit line by the isolation spacer. ### Claim 10 (depends on 1) The semiconductor device of claim 1, wherein the ratio between the thickness of the lower portion and the thickness of the upper portion of the air gap protection structure is equal to or greater than 0.66. ### Claim 11 A method of manufacturing a semiconductor device, comprising: providing a substrate; forming a bit line on the substrate; forming an isolation spacer on a side of the bit line, wherein the isolation spacer comprises an air gap; forming a landing pad over the bit line; and forming an air gap protection structure to cover the landing pad and the air gap, wherein the air gap protection structure has an upper portion above a top surface of the landing pad and a lower portion below the upper portion, and a ratio between a thickness of the lower portion and a thickness of the upper portion is greater than 0.6 and less than 0.8. ### Claim 12 (depends on 11) The method of claim 11, wherein the air gap protection structure comprises silicon nitride. ### Claim 13 (depends on 12) The method of claim 12, wherein the air gap protection structure comprises carbon. ### Claim 14 (depends on 12) The method of claim 12, wherein the air gap protection structure comprises hydrogen. ### Claim 15 (depends on 11) The method of claim 11, further comprising: patterning the landing pad to define a hole over the air gap, wherein the lower portion of the air gap protection structure is formed within the hole. ### Claim 16 (depends on 15) The method of claim 15, wherein the hole defined by the air gap protection structure has a smaller aperture near the upper portion of the air gap protection structure and a greater aperture near the lower portion of the air gap protection structure. ### Claim 17 (depends on 15) The method of claim 15, wherein an aspect ratio of the hole is greater than 2. ### Claim 18 (depends on 11) The method of claim 11, wherein the ratio between the thickness of the lower portion and the thickness of the upper portion of the air gap protection structure is equal to or greater than 0.66. ### Claim 19 (depends on 11) The method of claim 11, wherein forming the air gap protection structure comprises performing a deposition process, and gases used in the deposition process comprise SiH4, NH3, tetramethylsilane, and N2. ### Claim 20 (depends on 11) The method of claim 11, wherein He is not used during depositing the air gap protection structure.