# US 12,002,697 B2 · Method for detecting the splitting of a substrate weakened by implanting atomic species > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,002,697 B2 - Document ID: US12002697B2 - Status: Granted - Kind: B2 - Application number: 17/042,755 - Filed: 2019-03-22 - Published: 2021-01-28 - Granted: 2024-06-04 - Earliest claimed: 2018-03-28 - Assignees: Soitec - Applicants: Soitec; Commissariat A L'Energie Atomique et aux Énergies Alternatives - Inventors: François Rieutord; Frédéric Mazen; Didier Landru; Oleg Kononchuk; Nadia Ben Mohamed - Web page: https://patentgrep.com/patent/US12002697B2 ## CPC - H10P 72/0616: {Monitoring of warpages, curvatures, damages, defects or the like} - G01N 29/14: using acoustic emission techniques {(echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00)} - G01N 29/46: by spectral analysis, e.g. Fourier analysis {or wavelet analysis (spectral signal processing per se G06F17/14)} - H10P 72/0434: {mainly by convection} - H10P 72/3311: {Horizontal transfer of a batch of workpieces} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - H10P 90/1916: {with separation or delamination along an ion implanted layer, e.g. Smart-cut} - H10W 10/181: {Semiconductor-on-insulator [SOI] isolation regions, e.g. buried oxide regions of SOI wafers} - G01N 2291/2697: Wafer or (micro)electronic parts - H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A method for monitoring a heat treatment applied to a substrate comprising a weakened zone formed by implanting atomic species for splitting the substrate along the weakened zone, the substrate being arranged in a heating chamber, the method comprising recording sound in the interior or in the vicinity of the heating chamber and detecting, in the recording, a sound emitted by the substrate during the splitting thereof along the weakened zone. A device for the heat treatment of a batch of substrates comprises an annealing furnace comprising a heating chamber intended to receive the batch, at least one microphone configured to record sounds in the interior or in the vicinity of the heating chamber, and a processing system configured to detect, in an audio recording produced by the microphone, a sound emitted when a substrate splits. ## Claims ### Claim 1 A method for monitoring a heat treatment applied to a batch of substrates in a heating chamber, each substrate comprising a weakened zone formed by implanting atomic species for splitting the substrate along the weakened zone, the method comprising: recording sound in the interior or in the vicinity of the heating chamber; detecting, in the recording, an acoustic signature emitted by each substrate during the splitting thereof along the weakened zone; determining, based on the detected acoustic signature, that a splitting of each substrate along the weakened zone has occurred; determining a number of substrates having split; comparing the number of substrates having split to the number of substrates in the batch; and stopping the heat treatment once each substrate has been detected to have split. ### Claim 2 (depends on 1) The method of claim 1, wherein the recording is made with a microphone located in the interior of the heating chamber. ### Claim 3 (depends on 1) The method of claim 1, wherein the recording is made with a microphone arranged on an exterior wall of an annealing furnace containing the heating chamber. ### Claim 4 (depends on 1) The method of claim 1, wherein the recording is made with a microphone located between a thermal screen and a door of an annealing furnace allowing access to the heating chamber. ### Claim 5 (depends on 1) The method of claim 1, wherein the recording is made with a microphone located in a tube that opens onto the interior of the heating chamber. ### Claim 6 (depends on 1) The method of claim 1, further recording the sound from the interior or in the vicinity of the heating chamber. ### Claim 7 (depends on 1) The method of claim 1, further comprising recording sound in the interior or in the vicinity of the heating chamber using two microphones located at distance from each other, and, on the basis of a time shift between the sounds of the splitting of a substrate detected in the recording of each of the microphones, locating within the batch the substrate for which splitting has occurred. ### Claim 8 (depends on 7) The method of claim 7, wherein the microphones are located in opposite regions of the heating chamber. ### Claim 9 (depends on 1) The method of claim 1, wherein, after a preset length of time, the number of substrates detected to have split is lower than the number of substrates, and further comprising unloading the batch and separating the split substrates manually. ### Claim 10 (depends on 1) The method of claim 1, wherein a vibration frequency of a substrate during splitting is determined from a maximum frequency of the sound generated by the splitting of the substrate, and a splitting speed of the substrate is determined from the vibration frequency. ### Claim 11 (depends on 1) The method of claim 1, further comprising: processing a signal related to the sound to determine a sound intensity; and based on the determined sound intensity, computing an energy released during the splitting of a substrate. ### Claim 12 (depends on 1) The method of claim 1, further comprising: processing a signal related to the detected acoustic signature to determine a maximum frequency corresponding to a peak sound intensity, and based on the determined maximum frequency, computing a speed of a splitting wave propagating through a substrate. ### Claim 13 (depends on 1) The method of claim 1, wherein each substrate comprises at least one semiconductor material. ### Claim 14 A device for heat treatment of a batch of substrates each comprising a weakened zone formed by implanting atomic species for splitting the substrate along the weakened zone, the device comprising: an annealing furnace comprising a heating chamber configured to simultaneously receive the whole of the batch; at least one microphone configured to record sounds in the interior or in the vicinity of the heating chamber; a processing system configured to detect, in an audio recording produced by the at least one microphone, an acoustic signature emitted when a substrate splits along the weakened zone, to determine that splitting of each substrate along each respective weakened zone has occurred based on the detected acoustic signature, the processing system further configured to determine the number of substrates having split and to compare the number of substrates having split to the number of substrates in the batch; and a system for controlling the furnace, the system for controlling the furnace being configured to stop the heat treatment once all the substrates of the batch have been detected to have split. ### Claim 15 (depends on 14) The device of claim 14, wherein the at least one microphone is located in a tube opening into the interior of the heating chamber. ### Claim 16 (depends on 14) The device of claim 14, further comprising at least two microphones located at a distance from one another. ### Claim 17 (depends on 16) The device of claim 16, wherein the processing system is configured, on the basis of a time shift between the sounds of the splitting of a substrate detected in the recording of each of the at least two microphones, to locate within the batch the substrate for which splitting has occurred. ### Claim 18 (depends on 14) The device of claim 14, further comprising a system for controlling the furnace, the system configured to stop the heat treatment once all the substrates of the batch have been detected to have split. ### Claim 19 A method for monitoring a heat treatment applied to a substrate comprising a weakened zone formed by implanting atomic species with a view to splitting said substrate along said weakened zone, the substrate being arranged in a heating chamber, the method comprising: recording sound in the interior or in the vicinity of the heating chamber; detecting, in said recording, an acoustic signature emitted by the substrate during the splitting thereof along the weakened zone; determining, based on the detected acoustic signature, that a splitting of the substrate along the weakened zone has occurred; processing a signal related to the sound to determine a sound intensity; and based on the determined sound intensity, computing an energy released during the splitting of a substrate. ### Claim 20 A method for monitoring a heat treatment applied to a substrate comprising a weakened zone formed by implanting atomic species with a view to splitting said substrate along said weakened zone, the substrate being arranged in a heating chamber, the method comprising: recording sound in the interior or in the vicinity of the heating chamber; detecting, in said recording, an acoustic signature emitted by the substrate during the splitting thereof along the weakened zone; determining, based on the detected acoustic signature, that a splitting of the substrate along the weakened zone has occurred; processing a signal related to the detected acoustic signature to determine a maximum frequency corresponding to a peak sound intensity; and based on the determined maximum frequency, computing a speed of a splitting wave propagating through a substrate.