# US 2018/0026113 A1 · Fin-based rf diodes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026113 A1 - Document ID: US20180026113A1 - Status: Published application - Kind: A1 - Application number: 15/616,653 - Filed: 2017-06-07 - Published: 2018-01-25 - Earliest claimed: 2016-07-25 - Assignees: Globalfoundries Inc. - Applicants: GLOBALFOUNDRIES Inc. - Inventors: Jagar SINGH - Web page: https://patentgrep.com/patent/US20180026113A1 ## CPC - H10W 10/014: {using trench refilling with dielectric materials, e.g. shallow trench isolations} - H10D 8/00: Diodes (variable-capacitance diodes H10D1/64; gated diodes H10D12/00) - H10D 8/045: {of PN junction diodes} - H10D 8/051: {of Schottky diodes} - H10D 8/60: Schottky-barrier diodes - H10D 62/117: {Shapes of semiconductor bodies} - H10D 62/125: {Shapes of junctions between the regions} - H10W 10/17: formed using trench refilling with dielectric materials, e.g. shallow trench isolations - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract Methods for forming a fin-based RF diode with improved performance characteristics and the resulting devices are disclosed. Embodiments include forming fins over a substrate, separated from each other, each fin having a lower portion and an upper portion; forming STI regions over the substrate, between the lower portions of adjacent fins; implanting the lower portion of each fin with a first-type dopant; implanting the upper portion of each fin, above the STI region, with the first-type dopant; forming a junction region around a depletion region and along exposed sidewalls and a top surface of the upper portion of each fin; and forming a contact on exposed sidewalls and a top surface of each junction region. ## Claims ### Claim 1 A device comprising: fins over a substrate, separated from each other, each fin having a lower portion and an upper portion; shallow trench isolation (STI) regions over the substrate, between the lower portions of adjacent fins; the lower portion of each fin implanted with a first-type dopant; the upper portion of each fin, above the STI region, implanted with the first-type dopant; a junction region around a depletion region and along exposed sidewalls and a top surface of the upper portion of each fin; and a contact layer on a top surface of each junction region. ### Claim 2 (depends on 1) The device according to claim 1, wherein the first-type dopant comprises a p-type dopant. ### Claim 3 (depends on 2) The device according to claim 2, wherein the first-type dopant comprises boron. ### Claim 4 (depends on 1) The device according to claim 1, wherein the lower portion of each fin is implanted with the first-type dopant to a higher concentration level than the upper portion of each fin. ### Claim 5 (depends on 4) The device according to claim 4, wherein the lower portion has a concentration of 1e14 to 1e16 and the upper portion has a concentration of 1e12 to 1e14. ### Claim 6 (depends on 1) The device according to claim 1, wherein the upper portion of each fin has a top surface narrower than a bottom surface. ### Claim 7 (depends on 1) The device according to claim 1, further comprising: an active depletion region between the depletion region and the lower portion of each fin. ### Claim 8 (depends on 1) The device according to claim 1, wherein the junction region, including the exposed sidewalls and the top surface of each fin, is implanted with a diode cathode dopant. ### Claim 9 (depends on 8) The device according to claim 8, wherein the diode cathode dopant comprises an n-type dopant. ### Claim 10 (depends on 9) The device according to claim 9, wherein the n-type dopant comprises phosphorus. ### Claim 11 (depends on 1) The device according to claim 1, wherein the junction region comprises a layer of silicide gate material on the exposed sidewalls and the top surface of each fin. ### Claim 12 (depends on 1) The device according to claim 1, wherein the contact layer on the top surface of each junction region comprises titanium silicide (TiSi). ### Claim 13 A device comprising: fins over a substrate, separated from each other, each fin having a lower portion and an upper portion; shallow trench isolation (STI) regions over the substrate, between the lower portions of adjacent fins; the lower portion of each fin implanted with a first-type dopant; the upper portion of each fin, above the STI region, implanted with the first-type dopant; a depletion region in the upper portion of each fin; a junction region around the depletion region and along exposed sidewalls and a top surface of the upper portion of each fin; an active depletion region between the depletion region and the lower portion of each fin; and a titanium silicide (TiSi) layer on exposed sidewalls and top surface of the junction region. ### Claim 14 (depends on 13) The device according to claim 13, wherein the lower portion of each fin is implanted with the first-type dopant to a higher concentration level than the upper portion of each fin. ### Claim 15 (depends on 14) The device according to claim 14, wherein the lower portion has a concentration of 1e14 to 1e16 and the upper portion has a concentration of 1e12 to 1e14. ### Claim 16 (depends on 13) The device according to claim 13, wherein the upper portion of each fin has a top surface narrower than a bottom surface. ### Claim 17 (depends on 13) The device according to claim 13, wherein the junction region over the exposed sidewalls and top surface of the upper portion of the plurality of fins is an effective area. ### Claim 18 (depends on 13) The device of claim 13, wherein the junction region has a width of 48 nanometer (nm) for a planar diode and 13 nm for a conventional fin based diode. ### Claim 19 A device comprising: fins over a substrate, separated from each other, each fin having a lower portion and an upper portion, and wherein the upper portion of each fin has a top surface narrower than a bottom surface; shallow trench isolation (STI) regions over the substrate, between the lower portions of adjacent fins; the lower portion of each fin implanted with boron (B) at a concentration of 1e14 to 1e16; the upper portion of each fin, above the STI region, implanted with B at a concentration of 1e12 to 1e14; a junction region around a depletion region and along exposed sidewalls and a top surface of the upper portion of each fin; and a titanium silicide (TiSi) layer on exposed sidewalls and top surface of the junction region. ### Claim 20 (depends on 19) The device according to claim 19, wherein the junction region comprises a layer of silicide gate material implanted with a diode cathode dopant.