# US 11,309,196 B2 · Detection of adhesive residue on a wafer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,196 B2 - Document ID: US11309196B2 - Status: Granted - Kind: B2 - Application number: 16/588,433 - Filed: 2019-09-30 - Published: 2020-04-02 - Granted: 2022-04-19 - Earliest claimed: 2018-10-01 - Assignees: Infineon Technologies AG - Applicants: Infineon Technologies AG - Inventors: Robert Muhr; Matthias Fehr; Walter Leitgeb - Web page: https://patentgrep.com/patent/US11309196B2 ## CPC - H10P 72/0442: {Apparatus for placing on an insulating substrate, e.g. tape} - H10P 72/74: {using temporarily an auxiliary support} - G06T 7/0004: {Industrial image inspection} - H04N 23/74: by influencing the scene brightness using illuminating means - H04N 23/90: Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums - H10P 72/0436: {mainly by radiation} - H10P 72/0604: {Process monitoring, e.g. flow or thickness monitoring} - H10P 72/0614: {Marking devices} - H10P 72/7402: {Wafer tapes, e.g. grinding or dicing support tapes} - H10P 72/7448: {the bond interface between the auxiliary support and the wafer comprising two or more, e.g. multilayer adhesive or adhesive and release layer} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - G06T 2207/10048: Infrared image - G06T 2207/10064: Fluorescence image - G06T 2207/30148: Semiconductor; IC; Wafer - H10P 72/7412: {the auxiliary support including means facilitating the separation of a device or wafer from the auxiliary support} - H10P 72/7416: {used during dicing or grinding} - H10P 72/7422: {used to protect an active side of a device or wafer} - H10P 72/744: {Details of chemical or physical process used for separating the auxiliary support from a device or a wafer} - H10P 72/7442: {Separation by peeling} - H10P 72/7444: {using a peeling wedge, a knife or a bar} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A method of detecting adhesive residue on a wafer after peeling an adhesive film from the wafer by using a peeling tape is described. According to a first aspect, the method includes illuminating the peeling tape with first UV light after the peeling and acquiring a fluorescence image from the peeling tape. According to a second aspect, the method includes illuminating the wafer with second UV light after the peeling and acquiring a fluorescence image from the wafer. ## Claims ### Claim 1 A method of detecting adhesive residue the method comprising: applying an adhesive film on an upper surface of a wafer; peeling the adhesive film away from the upper surface of the wafer by using a peeling tape; illuminating the peeling tape with first UV light after the peeling; and acquiring a fluorescence image from the peeling tape and/or illuminating the wafer with second UV light after the peeling; and acquiring a fluorescence image from the wafer, wherein the fluorescence image is acquired from the wafer after the peeling. ### Claim 2 (depends on 1) The method of claim 1, wherein the first UV light is directed towards a first side of the peeling tape, and wherein the first side of the peeling tape faces the wafer during the peeling. ### Claim 3 (depends on 2) The method of claim 2, further comprising: illuminating a second side of the peeling tape opposite the first side with first visible or IR backlight after the peeling; and acquiring a backlight image from the peeling tape. ### Claim 4 (depends on 3) The method of claim 3, wherein the fluorescence image from the peeling tape and the backlight image from the peeling tape are acquired with a same first camera having separate channels for fluorescence light from first UV light and first visible or IR backlight and/or using first UV light and first visible or IR backlight multiplexing. ### Claim 5 (depends on 1) The method of claim 1, further comprising: illuminating the wafer with a second visible or IR backlight after the peeling; and acquiring a backlight image from the wafer. ### Claim 6 (depends on 5) The method of claim 5, wherein the fluorescence image from the wafer and the backlight image from the wafer are acquired with a same second camera having separate channels for fluorescence light from second UV light and second visible or IR backlight and/or using second UV light and second visible or IR backlight multiplexing. ### Claim 7 (depends on 1) The method of claim 1, further comprising: illuminating the wafer with a frontlight in the visible or IR range before and/or after the peeling; and acquiring a frontlight image from the wafer. ### Claim 8 (depends on 1) The method of claim 1, further comprising: using the second UV light to illuminate a peeling chuck when no wafer is disposed thereon; and acquiring a fluorescence image from the peeling chuck. ### Claim 9 (depends on 1) The method of claim 1, further comprising: marking a section of the peeling tape with a label indicative of the particular wafer which was peeled with the corresponding section of the peeling tape. ### Claim 10 (depends on 1) The method of claim 1, wherein the method comprises acquiring the fluorescence image from the peeling tape, and wherein acquiring the fluorescence image from the peeling tape comprises generating the fluorescence image to depict a contrast between intact regions of the adhesive film that are present on the peeling tape and regions of the peeling tape that are devoid of the adhesive film. ### Claim 11 (depends on 1) The method of claim 1, wherein the adhesive film is applied such that the adhesive film completely covers the upper surface of the wafer. ### Claim 12 An apparatus for detecting adhesive residue the apparatus comprising: a mechanism configured to apply an adhesive film on an upper surface of a wafer and to peel an adhesive film away from the upper surface of the wafer by using a peeling tape; and a first UV light source configured to illuminate the peeling tape that with first UV light after the peeling; and a first camera configured to acquire a fluorescence image from the peeling tape and/or a second UV light source configured to illuminate the wafer with second UV light after the peeling; and a second camera configured to acquire a fluorescence image from the wafer, wherein the second camera is configured to acquire the fluorescence image from the wafer with the second UV light after the peeling. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the first UV light source and the first camera are accommodated in a movable peeling unit configured to translate forward and backward across the wafer. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the first UV light source is configured to illuminate the peeling tape at a position on a peeling bar arranged adjacent to the wafer. ### Claim 15 (depends on 12) The apparatus of claim 12, wherein the first UV light source and the first camera are stationary relative to the peeling position of the wafer. ### Claim 16 (depends on 12) The apparatus of claim 12, wherein the first camera and/or the second camera is a line scan camera or an area scan camera. ### Claim 17 (depends on 12) The apparatus of claim 12, wherein the first UV light source and the first camera and/or the second UV light source and the second camera comprise an array of contact image sensors with integrated illumination. ### Claim 18 (depends on 12) The apparatus of claim 12, wherein the first camera is configured to acquire the fluorescence image from the peeling tape, and wherein the first camera is configured to acquire the fluorescence image by generating the fluorescence image to depict a contrast between intact regions of the adhesive film that are present on the peeling tape and regions of the peeling tape that are devoid of the adhesive film. ### Claim 19 (depends on 12) The apparatus of claim 12, wherein the mechanism is configured to apply the adhesive film such that the adhesive film completely covers the upper surface of the wafer.