# US 11,114,274 B2 · Method and system for testing an integrated circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,114,274 B2 - Document ID: US11114274B2 - Status: Granted - Kind: B2 - Application number: 16/725,287 - Filed: 2019-12-23 - Published: 2021-06-24 - Granted: 2021-09-07 - Earliest claimed: 2019-12-23 - Assignees: Carl Zeiss SMT GmbH - Applicants: Carl Zeiss SMT GmbH - Inventors: Theodore Lundquist; Baohua Niu - Web page: https://patentgrep.com/patent/US11114274B2 ## CPC - H01J 37/226: {Optical arrangements for illuminating the object; optical arrangements for collecting light from the object} - H01J 37/244: Detectors; Associated components or circuits therefor - G01R 31/307: of integrated circuits - H01J 37/268: {with scanning beams} - H01J 37/28: with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes} - H01J 2237/2445: Photon detectors for X-rays, light, e.g. photomultipliers - H01J 2237/2448: Secondary particle detectors - H01J 2237/24592: Inspection and quality control of devices - H01J 2237/2594: Measuring electric fields or potentials - H01J 2237/2808: Cathodoluminescence - H01J 2237/2817: Pattern inspection - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract A method for analyzing an integrated circuit includes: applying an electric test pattern to the IC; delivering a stream of primary electrons to a back side of the IC on an active region to a transistor of interest, the active region including active structures such as transistors of the IC; detecting light resulting from cathodoluminescence initiated by secondary electrons in the IC; and analyzing the detected light regarding a correlation with the electric test pattern applied to the IC. A system for analyzing an IC is provided. ## Claims ### Claim 1 A method, comprising: a) applying an electric test pattern to an integrated circuit (IC); b) delivering a beam primary electrons to a side of the IC on an active region comprising active structures of the IC; c) detecting light resulting from cathodoluminescence initiated by secondary electrons in the IC; and d) analyzing the detected light to correlate the detected light with the electric test pattern applied to the IC, wherein the electron beam has a resolution, the resolution is about a size of the active structure, and the resolution is less than a spacing between active structures of the IC. ### Claim 2 (depends on 1) The method of claim 1, wherein detecting the light comprises at least one member selected from the group consisting of detecting a number of photons of the light, detecting photon wavelengths of the light, detecting a polarization of the light, and detecting an angle of the light. ### Claim 3 (depends on 1) The method of claim 1, wherein an area of the IC covered by the electron beam is less than a spacing between transistors of the IC, and/or wherein an energy of the electron beam is equal or lower than 500 eV. ### Claim 4 (depends on 1) The method of claim 1, further comprising detecting secondary electrons released from the IC. ### Claim 5 (depends on 1) The method of claim 1, wherein c) comprises using at least one mirror to divert the catholuminescence to a detector. ### Claim 6 (depends on 1) The method of claim 1, wherein applying a test pattern comprises operating the IC so that at least one transistor of the IC is switching. ### Claim 7 (depends on 1) The method of claim 1, further comprising at least partially thinning a semiconductor substrate of the IC, and delivering the electron beam to the thinned portion of the IC. ### Claim 8 (depends on 7) The method claim 7, wherein the thinned portion covers one or more transistors. ### Claim 9 (depends on 1) The method of claim 1, wherein analyzing comprises analyzing a timely variation of photons. ### Claim 10 (depends on 1) The method of claim 1, further comprising scanning an area of interest of the IC. ### Claim 11 (depends on 1) The method of claim 1, further comprising performing a)-c) in a loop to improve the signal to noise ratio by repetition. ### Claim 12 (depends on 1) The method of claim 1, wherein the active structures of the IC comprise transistors. ### Claim 13 A method, comprising: analyzing cathodoluminescence light emitted from integrated circuit (IC) due to the delivery of a beam of primary electrons to a side of the IC on an active region comprising active structures of the IC while applying an electric test pattern to the IC, thereby correlating the cathodoluminescence light with the electric test pattern applied to the IC, wherein the electron beam has a resolution, the resolution is about a size of the active structure, and the resolution is less than a spacing between active structures of the IC. ### Claim 14 (depends on 13) The method of claim 13, further comprising detecting the cathodoluminescence light by a process which comprises at least one member selected from the group consisting of detecting a number of photons of the light, detecting photon wavelengths of the light, detecting a polarization of the light, and detecting an angle of the light. ### Claim 15 (depends on 13) The method of claim 13, wherein analyzing the cathodoluminescence light comprises analyzing a timely variation of photons. ### Claim 16 A method, comprising: analyzing cathodoluminescence light emitted from integrated circuit (IC) due to the delivery of a beam of primary electrons to a side of the IC on an active region comprising active structures of the IC while applying an electric test pattern to the IC, thereby correlating the cathodoluminescence light with the electric test pattern applied to the IC, wherein analyzing the cathodoluminescence light comprises analyzing a timely variation of photons. ### Claim 17 (depends on 16) The method of claim 16, further comprising detecting the cathodoluminescence light by a process which comprises at least one member selected from the group consisting of detecting a number of photons of the light, detecting photon wavelengths of the light, detecting a polarization of the light, and detecting an angle of the light. ### Claim 18 A method, comprising: a) applying an electric test pattern to an integrated circuit (IC); b) delivering a beam primary electrons to a side of the IC on an active region comprising active structures of the IC; c) detecting light resulting from cathodoluminescence initiated by secondary electrons in the IC; and d) analyzing the detected light to correlate the detected light with the electric test pattern applied to the IC, wherein analyzing comprises analyzing a timely variation of photons. ### Claim 19 (depends on 18) The method of claim 18, wherein detecting the light comprises at least one member selected from the group consisting of detecting a number of photons of the light, detecting photon wavelengths of the light, detecting a polarization of the light, and detecting an angle of the light. ### Claim 20 (depends on 18) The method of claim 18, wherein: the electron beam has a resolution; the resolution is about a size of the active structure, the resolution is less than a spacing between active structures of the IC; and an area of the IC covered by the electron beam is less than a spacing between transistors of the IC, and/or wherein an energy of the electron beam is equal or lower than 500 eV. ### Claim 21 (depends on 18) The method of claim 18, further comprising detecting secondary electrons released from the IC. ### Claim 22 (depends on 18) The method of claim 18, wherein c) comprises using at least one mirror to divert the catholuminescence to a detector. ### Claim 23 (depends on 18) The method of claim 18, wherein applying a test pattern comprises operating the IC so that at least one transistor of the IC is switching. ### Claim 24 (depends on 18) The method of claim 18, further comprising at least partially thinning a semiconductor substrate of the IC, and delivering the electron beam to the thinned portion of the IC. ### Claim 25 (depends on 24) The method claim 24, wherein the thinned portion covers one or more transistors. ### Claim 26 (depends on 18) The method of claim 18, further comprising scanning an area of interest of the IC. ### Claim 27 (depends on 18) The method of claim 18, further comprising performing a)-c) in a loop to improve the signal to noise ratio by repetition. ### Claim 28 (depends on 18) The method of claim 18, wherein the active structures of the IC comprise transistors.