# US 11,908,724 B2 · Method and apparatus for measuring placement of a substrate on a heater pedestal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,908,724 B2 - Document ID: US11908724B2 - Status: Granted - Kind: B2 - Application number: 17/845,816 - Filed: 2022-06-21 - Published: 2022-10-06 - Granted: 2024-02-20 - Earliest claimed: 2018-09-04 - Assignees: Applied Materials, Inc. - Applicants: Applied Materials, Inc. - Inventors: Charles G. Potter; Anthony D. Vaughan - Web page: https://patentgrep.com/patent/US11908724B2 ## CPC - H10P 72/53: {using optical controlling means} - B25J 9/1692: {Calibration of manipulator} - B25J 13/086: {Proximity sensors} - G01B 7/14: for measuring distance or clearance between spaced objects or spaced apertures (G01B7/30 takes precedence) - G01D 5/24: by varying capacitance - H10P 72/0432: {mainly by conduction} - H10P 72/0606: {Position monitoring, e.g. misposition detection or presence detection} - H10P 72/7602: {the wafers being placed on a robot blade or gripped by a gripper for conveyance} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR ## Abstract Embodiments disclosed herein include a method of determining the position of a sensor wafer relative to a pedestal. In an embodiment, the method comprises placing a sensor wafer onto the pedestal, wherein the sensor wafer comprises a first surface that is supported by the pedestal, a second surface opposite the first surface, and an edge surface connecting the first surface to the second surface, wherein a plurality of sensor regions are formed on the edge surface, and wherein the pedestal comprises a major surface and an annular wall surrounding the sensor wafer. In an embodiment, the method further comprises determining a gap distance between each of the plurality of sensor regions and the annular wall. In an embodiment, the method may further comprise determining a center-point offset of a center-point of the sensor wafer relative to a center point of the annular wall from the gap distances. ## Claims ### Claim 1 A placement controller, comprising: a sensor interface, wherein the sensor interface is configured to receive sensor information from a sensor wafer, the sensor wafer comprising a plurality of outward facing sensors along an edge surface of the sensor wafer, and the sensor wafer comprising a plurality of discrete recesses, each recess radially between a corresponding one of the plurality of outward facing sensor regions and a center of the sensor wafer, and each recess exposing an inner lateral edge of the corresponding one of the plurality of outward facing sensor regions, wherein each of the plurality of recesses is non-continuous with one another; and a center-point module, wherein the center-point module is configured to utilizes the sensor information to determine a center-point of the sensor wafer relative to a center-point of a pedestal on which the sensor wafer rests, and wherein the placement controller is configured to control a positioning robot that places the sensor wafer on the pedestal. ### Claim 2 (depends on 1) The placement controller of claim 1, wherein the placement controller generates a position offset value that is stored in a database. ### Claim 3 (depends on 2) The placement controller of claim 2, wherein the position offset value is used to control the positioning robot as it places wafers on the pedestal. ### Claim 4 (depends on 1) The placement controller of claim 1, wherein the pedestal is a heater pedestal. ### Claim 5 (depends on 1) The placement controller of claim 1, wherein the sensors of the sensor wafer are self-referencing capacitive sensors. ### Claim 6 (depends on 1) The placement controller of claim 1, wherein the plurality of outward facing sensors comprises at least three outward facing sensors. ### Claim 7 (depends on 1) The placement controller of claim 1, wherein the controller is for determining a gap distance between each of the plurality of outward facing sensors and an annular wall.