# US 12,183,634 B2 · Selective recessing to form a fully aligned via > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,183,634 B2 - Document ID: US12183634B2 - Status: Granted - Kind: B2 - Application number: 18/381,969 - Filed: 2023-10-19 - Published: 2024-10-17 - Granted: 2024-12-31 - Earliest claimed: 2016-08-05 - Assignees: Adeia Semiconductor Solutions LLC - Applicants: Adeia Semiconductor Solutions LLC - Inventors: Benjamin D. Briggs; Jessica Dechene; Elbert Huang; Joe Lee; Thedorus E. Standaert - Web page: https://patentgrep.com/patent/US12183634B2 ## CPC - H10W 20/069: {by forming self-aligned vias or self-aligned contact plugs} - H10W 20/056: {by filling conductive material into holes, grooves or trenches} - H10W 20/062: {by smoothing of conductive parts, e.g. by planarisation} - H10W 20/0693: {by forming self-aligned vias} - H10W 20/077: {on sidewalls or on top surfaces of conductors (H10W20/076 takes precedence)} - H10W 20/086: {involving buried masks} - H10W 20/42: Vias, e.g. via plugs - H10W 20/435: {Cross-sectional shapes or dispositions of interconnections} - H10W 20/4421: {the principal metal being copper} - H10W 20/48: Insulating materials thereof - H10W 20/072: {of dielectric parts comprising air gaps} - H10W 20/0882: {wherein the dual damascene structure is in a photoresist layer} - H10W 20/46: comprising air gaps - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A method of forming a semiconductor device having a vertical metal line interconnect (via) fully aligned to a first direction of a first interconnect layer and a second direction of a second interconnect layer in a selective recess region by forming a plurality of metal lines in a first dielectric layer; and recessing in a recess region first portions of the plurality of metal lines such that top surfaces of the first portions of the plurality of metal lines are below a top surface of the first dielectric layer; wherein a non-recess region includes second portions of the plurality of metal lines that are outside the recess region. ## Claims ### Claim 1 A device comprising: an interconnect structure comprising first and second metal lines formed in a first dielectric layer, wherein: the second metal line extends parallel to the first metal line in a first direction; the second metal line is disposed adjacent to the first metal line; a first region comprises a first segment of the first metal line and an adjacent first segment of the second metal line; a second region comprises a second segment of the first metal line and an adjacent second segment of the second metal line; the second region is adjacent to the first region; and a top surface of the first segment of the first metal line and a top surface of the first segment of the second metal line are recessed relative to a top surface of the first dielectric layer and relative to a top surface of the second segment of the first metal line and a top surface of the second segment of the second metal line. ### Claim 2 (depends on 1) The device of claim 1, wherein: the first region is disposed between a third region and the second region, and the third region comprises a third segment of the first metal line and an adjacent third segment of the second metal line; and the top surface of the second segment of the first metal line and the top surface of the second segment of the second metal line are substantially coplanar with a top surface of the third segment of the first metal line and a top surface of the third segment of the second metal line. ### Claim 3 (depends on 1) The device of claim 1, further comprising a third metal line which (i) is formed in the first dielectric layer, (ii) extends in the first direction parallel to the first metal line and the second metal line, wherein: the first metal line is disposed between the third metal line and the second metal line, the first metal line is disposed adjacent to the third metal line and the second metal line, the first region comprises a first segment of the third metal line; and a top surface of the first segment of the third metal line is substantially coplanar with the top surface of the first segment of the first metal line and the top surface of the first segment of the second metal line. ### Claim 4 (depends on 1) The device of claim 1, further comprising a third metal line which (i) is formed in the first dielectric layer, (ii) extends in the first direction parallel to the first metal line and the second metal line, wherein: the second metal line is disposed between the third metal line and the first metal line, the second metal line is disposed adjacent to the third metal line and the first metal line the third metal line is disposed in a third region adjacent to the first and second regions, the third metal line comprises a first segment adjacent to the first segment of the second metal line and a second segment adjacent to the second segment of the second metal line, and a top surface of the first segment of the third metal line is substantially coplanar with a top surface of the second segment of the third metal line and the top surface of the second segment of the second metal line. ### Claim 5 (depends on 1) The device of claim 1, further comprising: an interlayer dielectric layer disposed on the first dielectric layer; and a via through the interlayer dielectric layer connected to the first segment of the first metal line. ### Claim 6 (depends on 5) The device of claim 5, wherein: the interlayer dielectric layer comprises (i) a cap layer and (ii) a second dielectric layer disposed on the cap layer; the cap layer comprises one or more first materials; the second dielectric layer comprises one or more second materials; and at least one of the one or more first materials is different from at least one of the one or more second materials. ### Claim 7 (depends on 6) The device of claim 6, wherein the cap layer comprises silicon and nitrogen. ### Claim 8 (depends on 6) The device of claim 6, wherein the cap layer comprises silicon, nitrogen, and carbon. ### Claim 9 (depends on 6) The device of claim 6, wherein the cap layer comprises a metal oxide. ### Claim 10 (depends on 2) The device of claim 2, further comprising: an interlayer dielectric layer disposed on the first dielectric layer; and a via through the interlayer dielectric layer connected to the first segment of the first metal line. ### Claim 11 (depends on 3) The device of claim 3, further comprising: an interlayer dielectric layer disposed on the first dielectric layer; and a via through the interlayer dielectric layer connected to the first segment of the first metal line. ### Claim 12 (depends on 4) The device of claim 4, further comprising: an interlayer dielectric layer disposed on the first dielectric layer; and a via through the interlayer dielectric layer connected to the first segment of the first metal line. ### Claim 13 A device comprising: an interconnect structure comprising first, second, and third metal lines formed in a first dielectric layer, wherein: the second and third metal lines extends parallel to the first metal line in a first direction; the first metal line is disposed (i) adjacent to the second metal line and the third metal line and (ii) between the second metal line and the third metal line; a first region comprises a first segment of the first metal line, a first segment of the second metal line and a first segment of the third metal line; a second region comprises a second segment of the first metal line, a second segment of the second metal line and a second segment of the third metal line; and a top surface of the first segment of the first metal line, a top surface of the first segment of the second metal line and a top surface of the first segment of the third metal line are recessed relative to a top surface of the first dielectric layer, relative to a top surface of the second segment of the first metal line, a top surface of the second segment of the second metal line, and a top surface of the second segment of the third metal line. ### Claim 14 (depends on 13) The device of claim 13, wherein: the first region is disposed between a third region and the second region, and the third region comprises adjacent third segments of the first, second, and third metal lines; and the top surface of the first segment of the first metal line, the top surface of the first segment of the second metal line and the top surface of the first segment of the third metal line are recessed relative to a top surface of the third segment of the first metal line, a top surface of the third segment of the second metal line and a top surface of the third segment of the third metal line. ### Claim 15 (depends on 13) The device of claim 13, comprising a fourth metal line which (i) is formed in the first dielectric layer, (ii) extends in the first direction parallel to the first metal line, the second metal line and the third metal line, wherein: the second metal line is disposed between and adjacent to the first metal line and the fourth metal line, a fourth region comprises first and second segments of the fourth metal line, adjacent to the first and second segments of the second metal line, respectively; and a top surface of the first segment of the fourth metal line is substantially coplanar with a top surface of the second segment of the fourth metal line and with the top surface of the second segment of the second metal line. ### Claim 16 (depends on 15) The device of claim 15, further comprising: an interlayer dielectric layer disposed on (i) the first dielectric layer, (ii) the first metal line, (iii) the second metal line, (iv) the third metal line, and (v) the fourth metal line; and a via through the interlayer dielectric layer connecting to the first segment of the first metal line. ### Claim 17 (depends on 13) The device of claim 13, further comprising: an interlayer dielectric layer disposed on (i) the first dielectric layer, (ii) the first metal line, (iii) the second metal line, and (iv) the third metal line; and a via through the interlayer dielectric layer connecting to the first segment of the first metal line. ### Claim 18 (depends on 14) The device of claim 14, further comprising: an interlayer dielectric layer disposed on (i) the first dielectric layer, (ii) the first metal line, (iii) the second metal line, and (iv) the third metal line; and a via through the interlayer dielectric layer connecting to the first segment of the first metal line. ### Claim 19 (depends on 16) The device of claim 16, wherein: the interlayer dielectric layer comprises (i) a cap layer and (ii) a second dielectric layer disposed on the cap layer; the cap layer comprises one or more first materials; the second dielectric layer comprises one or more second materials; and at least one of the one or more first materials is different from at least one of the one or more second materials. ### Claim 20 (depends on 19) The device of claim 19, wherein the cap layer comprises silicon and nitrogen. ### Claim 21 (depends on 19) The device of claim 19, wherein the cap layer comprises silicon, nitrogen, and carbon. ### Claim 22 (depends on 19) The device of claim 19, wherein the cap layer comprises a metal oxide.