# US 10,373,855 B2 · Method for processing a wafer and method for processing a carrier > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,373,855 B2 - Document ID: US10373855B2 - Status: Granted - Kind: B2 - Application number: 15/690,316 - Filed: 2017-08-30 - Published: 2018-03-01 - Granted: 2019-08-06 - Earliest claimed: 2016-08-31 - Assignees: Infineon Technologies AG - Applicants: Infineon Technologies AG - Inventors: Karl Pilch - Web page: https://patentgrep.com/patent/US10373855B2 ## CPC - H10P 72/74: {using temporarily an auxiliary support} - H10P 34/42: with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) - H10P 50/00: Etching of wafers, substrates or parts of devices - H10P 72/53: {using optical controlling means} - H10P 95/11: {Separation of active layers from substrates} - H10W 46/00: Marks applied to devices, e.g. for alignment or identification - H10P 72/744: {Details of chemical or physical process used for separating the auxiliary support from a device or a wafer} - H10W 46/301: {for alignment} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract According to various embodiments, a method for processing a wafer may include scanning a focused laser beam over the wafer to form a defect structure within the wafer, the defect structure defining a first region of the wafer located at a first side of the defect structure and a second region of the wafer located at a second side of the defect structure opposite the first side, and an edge region laterally surrounding the defect structure and extending from a first surface of the wafer to a second surface of the wafer opposite the first surface. A surface area of the first region is greater than a surface area of the edge region, and the second region is connected to the first region by the edge region. The method may further include, separating the first region and the second region from each other along the defect structure, with the first region remaining in one piece. ## Claims ### Claim 1 A method for processing a wafer, the method comprising: scanning a focused laser beam over the wafer to form a defect structure within the wafer, the defect structure defining a first region of the wafer located at a first side of the defect structure and a second region of the wafer located at a second side of the defect structure opposite the first side, and an edge region laterally surrounding the defect structure and extending from a first surface of the wafer to a second surface of the wafer opposite the first surface, wherein a surface area of the first region is greater than a surface area of the edge region, and wherein the second region is connected to the first region by the edge region, and, subsequently, separating the first region and the second region from each other along the defect structure, with the first region remaining in one piece, wherein the focused laser beam is scanned in a first plane having a first distance from the first surface and aligned in parallel to the first surface, and in a second plane having a second distance from the first surface and aligned in parallel to the first surface, wherein the second distance is greater than the first distance, and wherein the first plane defines chip regions in the first region and wherein the second plane defines kerf regions and chip edge regions laterally surrounding the chip regions respectively. ### Claim 2 (depends on 1) The method according to claim 1, wherein separating the first region and the second region from each other further comprises to lift off the second region in one piece from the first region. ### Claim 3 (depends on 1) The method according to claim 1, wherein the defect structure is formed under more than 80% of the first surface of the wafer. ### Claim 4 (depends on 1) The method according to claim 1, wherein scanning the focused laser beam over the wafer further comprises controlling a focus position of the focused laser beam and controlling an alignment of the wafer relative the focus position. ### Claim 5 (depends on 4) The method according to claim 4, wherein scanning the focused laser beam over the wafer is controlled via a feedback loop configured to check if a pattern of the formed defect structure is in alignment with a predefined pattern. ### Claim 6 (depends on 4) The method according to claim 4, wherein scanning the focused laser beam over the wafer is controlled via an infrared measuring arrangement. ### Claim 7 (depends on 1) The method according to claim 1, wherein the focused laser beam is scanned in a single plane that is aligned parallel to the first surface of the wafer to form a planar defect structure. ### Claim 8 (depends on 1) The method according to claim 1, wherein a thickness of the first region is less than about 50 μm. ### Claim 9 (depends on 1) The method according to claim 1, wherein scanning the focused laser beam over the wafer comprises operating a laser in a pulsed mode defining a pulse frequency, a pulse duration, and a power density. ### Claim 10 (depends on 9) The method according to claim 9, wherein the wafer comprises a material having a power density damage threshold and wherein the pulse energy is selected to provide the focused laser beam with a power density greater than the power density damage threshold. ### Claim 11 (depends on 10) The method according to claim 10, wherein the material is silicon and wherein the power density is greater than about 1·1010 W/cm2. ### Claim 12 (depends on 9) The method according to claim 9, wherein the pulse duration is less than about 1 ns. ### Claim 13 (depends on 9) The method according to claim 9, wherein the pulse frequency is greater than about 1 kHz. ### Claim 14 (depends on 1) The method according to claim 1, further comprising: before separating the first region and the second region from each other, forming a separation structure extending from the second surface of the wafer into the wafer to the defect structure, the separation structure laterally surrounding the second region. ### Claim 15 (depends on 14) The method according to claim 14, wherein the separation structure comprises a further defect structure. ### Claim 16 (depends on 1) The method according to claim 1, wherein separating the first region and the second region from each other comprises subjecting the wafer to a mechanical stress to break the defect structure. ### Claim 17 A method for processing a carrier, the method comprising: forming a defect structure within the carrier by scanning a focus region of a laser beam within the carrier, the defect structure defining a first region of the carrier located at a first side of the defect structure and a second region of the carrier located at a second side of the defect structure opposite the first side, and an edge region laterally surrounding the defect structure and extending from a first surface of the carrier to a second surface of the carrier opposite the first surface, wherein the defect structure is formed under more than 80% of the first surface, and wherein the second region is connected to the first region by the edge region, and, subsequently, separating the first region and the second region from each other by breaking the defect structure with at least the first region remaining in one piece, wherein the focus region of the laser beam is scanned in a first plane having a first distance from the first surface and aligned in parallel to the first surface, and in a second plane having a second distance from the first surface and aligned in parallel to the first surface, wherein the second distance is greater than the first distance, and wherein the first plane defines chip regions in the first region and wherein the second plane defines kerf regions and chip edge regions laterally surrounding the chip regions respectively. ### Claim 18 A method for processing a carrier, the method comprising: forming a defect structure within the carrier by scanning a focus region of a laser beam within the carrier, the defect structure laterally extending through the carrier and defining a first region of the carrier located above the defect structure and a second region of the carrier located below the defect structure, and, subsequently, separating the first region and the second region from each other by breaking the defect structure, wherein the focus region of the laser beam is scanned in a first plane having a first distance from a first surface of the carrier and aligned in parallel to the first surface, and in a second plane having a second distance from the first surface and aligned in parallel to the first surface, wherein the second distance is greater than the first distance, and wherein the first plane defines chip regions in the first region and wherein the second plane defines kerf regions and chip edge regions laterally surrounding the chip regions respectively.