Automatic calibration fixture for substrate transfer robots

Abstract

A robot calibration system includes a calibration fixture configured to be mounted to a substrate processing chamber. The calibration fixture includes at least one camera positioned to capture an image including an outer edge of a test substrate and an edge ring surrounding the test substrate. A controller is configured to receive the captured image, analyze the captured image to measure a distance between the outer edge of the test substrate and the edge ring, calculate a center of the test substrate based on the measured distance, and calibrate a robot configured to transfer substrates into and out of the substrate processing chamber based on the calculated center of the test substrate.

Description

Technical Field

[0001] <Cross - Reference to Related Applications> This application claims the benefit of U.S. Provisional Application No. 62 / 813,371, filed Mar. 4, 2019. The entire disclosure of the above application is incorporated herein by reference.

[0002] This disclosure relates to systems and methods for calibrating a robot of a substrate processing system.

Background Art

[0003] The description of the background art set forth herein is for the purpose of generally presenting the context of the disclosure. The inventions of the presently named inventors are not to be regarded as prior art to the disclosure, either explicitly or implicitly, to the extent that they are described in this background art section only or in an aspect of the description that does not fall within the ambit of prior art at the time of filing.

[0004] A substrate processing system may be used to process substrates such as semiconductor wafers. Exemplary processes that may be performed on a substrate include, but are not limited to, chemical vapor deposition (CVD), atomic layer deposition (ALD), conductor etching, and / or other etching, deposition, or cleaning processes. The substrate may be disposed on a substrate support such as a pedestal, an electrostatic chuck (ESC), within a processing chamber of the substrate processing system. During etching, a gas mixture containing one or more precursors may be introduced into the processing chamber, and plasma may be used to cause a chemical reaction.

Summary of the Invention

[0005] The robot calibration system includes a calibration fixture configured to be mounted in a substrate processing chamber. The calibration fixture includes at least one camera positioned to capture an image including the outer edge of the test substrate and the edge ring surrounding the test substrate. The controller is configured to receive and analyze the captured image to measure the distance between the outer edge of the test substrate and the edge ring, calculate the center of the test substrate based on the measured distance, and calibrate the robot configured to load and unload the substrate into and out of the substrate processing chamber based on the calculated center of the test substrate.

[0006] In other features, at least one camera is equivalent to three cameras. The robotic calibration system includes a compressed seal between the calibration fixture and the substrate processing chamber, and the controller is configured to reduce the pressure of the substrate processing chamber to a vacuum while the calibration fixture is attached to the substrate processing chamber. The controller is configured to control at least one camera to capture images while the substrate processing chamber is in a vacuum.

[0007] In other features, the controller is configured to determine the width of pixels in the field of view of at least one camera and to measure the distance between the outer edge of the test board and the edge ring based on the determined pixel width. The test board includes at least one reference marking located in the field of view of at least one camera, the at least one reference marking having known dimensions, and the controller is configured to determine the width of pixels based on the known dimensions. The at least one reference marking is a square, and the known dimension is the width of that square.

[0008] Other features include a reference line corresponding to its radius, and the controller is configured to measure the distance between the outer edge of the test board and the edge ring at a position corresponding to the reference line. The controller is configured to calculate a correction amount based on the calculated center of the test board and update the robot's coordinates based on the correction amount. The controller is configured to calculate a correction amount based on the offset between the calculated center of the test board and the center of the edge ring. The robot is calibrated by updating its multiple coordinates.

[0009] A method for calibrating a robot configured to load and unload substrates into and out of a substrate processing chamber equipped with a calibration jig fitted with at least one camera includes the step of capturing an image using at least one camera that includes the outer edge of a test substrate and an edge ring surrounding the test substrate. The method further includes the steps of analyzing the captured image to measure the distance between the outer edge of the test substrate and the edge ring, calculating the center of the test substrate based on the measured distance, and calibrating the robot configured to load and unload substrates into and out of the substrate processing chamber based on the calculated center of the test substrate.

[0010] In other features, at least one camera is equivalent to three cameras. This method further includes the step of reducing the substrate processing chamber to a vacuum. This method further includes the step of controlling at least one camera so that the substrate processing chamber captures an image while it is in a vacuum.

[0011] In other features, the method further includes the steps of determining the width of a pixel in the field of view of at least one camera, and measuring the distance between the outer edge of the test substrate and the edge ring based on the determined pixel width. The test substrate includes at least one reference marking located in the field of view of at least one camera, the at least one reference marking having known dimensions, and the pixel width is determined based on the known dimensions. The at least one reference marking is a square, and the known dimension is the width of that square.

[0012] Other features include the test board including a reference line corresponding to its radius, and the distance between the outer edge of the test board and the edge ring being measured at a position corresponding to the reference line. This method further includes the steps of calculating a correction amount based on the calculated center of the test board and calibrating the robot based on the correction amount. This method further includes the step of calculating a correction amount based on the offset between the calculated center of the test board and the center of the edge ring.

[0013] Further application areas of this disclosure will become apparent from the modes for carrying out the invention, the claims, and the drawings. The modes for carrying out the invention and specific examples are for illustrative purposes only and are not intended to limit the scope of this disclosure. [Brief explanation of the drawing]

[0014] This disclosure will be better understood from the embodiments for carrying out the invention and the accompanying drawings.

[0015] [Figure 1] Functional block diagram of an exemplary substrate processing system as described herein.

[0016] [Figure 2A] Exemplary calibration fixtures and robotic calibration systems as provided in this disclosure. [Figure 2B] Exemplary calibration fixtures and robotic calibration systems as provided in this disclosure. [Figure 2C] Exemplary calibration fixtures and robotic calibration systems as provided in this disclosure. [Figure 2D] Exemplary calibration fixtures and robotic calibration systems as provided in this disclosure.

[0017] [Figure 3] Steps of an exemplary method for calibrating a robot according to the present disclosure.

[0018] [Figure 4A] A diagram illustrating an exemplary calibration jig as described herein. [Figure 4B]Diagram of an exemplary calibration jig according to the present disclosure. [Figure 4C] Diagram of an exemplary calibration jig according to the present disclosure. [Figure 4D] Diagram of an exemplary calibration jig according to the present disclosure.

[0019] In the drawings, reference numbers may be repeated to identify similar and / or identical elements.

Embodiments for Carrying Out the Invention

[0020] In a substrate processing system, a robot / handler (e.g., a vacuum transfer module (VTM) robot) may be used to load and unload substrates to and from a substrate support within a processing chamber. Some substrate processing systems may implement a dynamic alignment system for aligning substrates on a substrate support using a robot. Substrates are aligned to enable accurate capture and / or transfer (e.g., to a process cell) of the substrates using a robot or other tool. Alignment of the substrate may be achieved using a notch formed on the outer edge of the substrate. Various types of substrate aligners may be used to detect the position of the notch when the substrate is rotating. For example, a sensor may detect the notch using a chuck when the substrate is rotating at a low speed. The notch position and substrate offset are calculated based on the detected notch and provided to the robot.

[0021] The robot may further be configured to load and unload an edge ring to and from the substrate support. The robot may be controlled according to predetermined calibration data to center the edge ring on the substrate support. Accurate installation of the edge ring on the substrate support may be difficult. For example, the desired position of the edge ring may be a position centered with respect to the substrate support. In some examples, the robot may be configured to transport the edge ring to a predetermined known centering position with respect to the substrate support. However, due to replacement of components of the substrate support, maintenance within the processing chamber, etc., the center position of the substrate support may change.

[0022] Therefore, the robot must be periodically calibrated to achieve accurate placement of the transported substrate, edge ring, and / or other components of the substrate processing system. Conventional robot calibration methods are prone to human error and system and / or process variations (such as vacuum deflection).

[0023] The robot calibration system and method according to the present disclosure provide a robot calibration jig configured to measure the distance between a substrate (e.g., a test substrate) disposed on a substrate support and an edge ring and calibrate the robot accordingly. For example, the robot calibration jig may include three or more imaging devices (e.g., cameras) arranged to measure the distance from the edge of the test substrate to the edge of the edge ring (e.g., the inner edge portion). In one example, the robot calibration jig includes three cameras mounted in a triangular arrangement. The test substrate may include fiducial markings to facilitate calculation of the position of the test substrate relative to the substrate. Based on the calculated value of the position of the test substrate relative to the edge ring, the system is configured to calculate adjustment information and control the robot to pick up and replace the test substrate. The pick-up and replacement may be repeated iteratively until the test substrate is in the desired position and the calibration of the robot is complete.

[0024] Referring here to Figure 1, an exemplary substrate processing system 100 is shown. For illustrative purposes only, the substrate processing system 100 may be used to perform etching and / or other suitable substrate processing using RF plasma. The substrate processing system 100 comprises a processing chamber 102 containing RF plasma, surrounding other components. The substrate processing chamber 102 comprises an upper electrode 104 and a substrate support 106 (such as an electrostatic chuck (ESC)). During operation, the substrate 108 is placed on the substrate support 106. Although a specific substrate processing system 100 and chamber 102 are shown as examples, the principles of this disclosure may also be applicable to other types of substrate processing systems and chambers, such as substrate processing systems that generate plasma in-situ, and substrate processing systems that generate and supply plasma remotely (e.g., using a plasma tube, microwave tube).

[0025] For illustrative purposes only, the upper electrode 104 may include a gas distribution device such as a showerhead 109 for introducing and distributing process gas. The showerhead 109 may include a stem portion with one end configured to receive process gas. The base portion is generally cylindrical and extends radially outward from the other end of the stem portion, away from the upper surface of the processing chamber 102. The substrate-facing surface of the base portion of the showerhead 109, or the faceplate, has a plurality of holes through which process gas or purge gas flows. Alternatively, the upper electrode 104 may include a conductive plate, and the process gas may be introduced by another means.

[0026] The substrate support 106 comprises a conductive base plate 110 that functions as a lower electrode. The base plate 110 supports a ceramic layer 112. In some examples, the ceramic layer 112 may include a heating layer, such as a ceramic multi-zone heating plate. A heat-resistant layer 114 (e.g., a bonding layer) may be placed between the ceramic layer 112 and the base plate 110. The base plate 110 may include one or more refrigerant channels 116 for circulating a refrigerant through it.

[0027] The RF generation system 120 generates an RF voltage and outputs it to either the upper electrode 104 or the lower electrode (e.g., the base plate 110 of the substrate support 106). The other of the upper electrode 104 and the base plate 110 may be DC grounded, AC grounded, or floating. For illustrative purposes only, the RF generation system 120 may include an RF voltage generator 122 that generates the RF voltage supplied to the upper electrode 104 or the base plate 110 by a matched distribution network 124. In other examples, the plasma may be generated inductively or remotely. As shown for illustrative purposes only, the RF generation system 120 corresponds to a capacitively coupled plasma (CCP) system, but the principles of the present disclosure may be implemented in other suitable systems, for illustrative purposes only, such as a transformer-coupled plasma (TCP) system, a CCP cathode system, or a remote microwave plasma generation and supply system.

[0028] The gas supply system 130 comprises one or more gas sources 132-1, 132-2, ..., and 132-N (collectively, gas source 132) (where N is an integer greater than zero). The gas sources supply one or more precursors and mixtures thereof. The gas sources may supply purge gas. Vaporized precursors may be used. The gas sources 132 are connected to the manifold 140 by valves 134-1, 134-2, ..., and 134-N (collectively, valve 134), and mass flow controllers 136-1, 136-2, ..., and 136-N (collectively, mass flow controller 136). The output of the manifold 140 is supplied to the processing chamber 102. For example, the output of the manifold 140 is supplied to the shower head 109.

[0029] The temperature controller 142 may be connected to a plurality of heating elements 144, such as thermal control elements (TCEs) arranged in the ceramic layer 112. For example, the heating elements 144 may include, but are not limited to, macro heating elements corresponding to each zone of a multizone heating plate and / or arrays of micro heating elements arranged across multiple zones of a multizone heating plate. The temperature controller 142 may be used to control the plurality of heating elements 144 to control the temperatures of the substrate support 106 and the substrate 108.

[0030] The temperature controller 142 may communicate with the refrigerant assembly 146 to control the flow of refrigerant through the channel 116. For example, the refrigerant assembly 146 may include a refrigerant pump and a tank. The temperature controller 142 operates the refrigerant assembly 146 to selectively flow the refrigerant through the channel 116 to cool the substrate support 106.

[0031] Valves 150 and pumps 152 may be used to discharge the reactant from the processing chamber 102. A system controller 160 may be used to control the components of the substrate processing system 100. A robot 170 may be used to supply and remove substrates to and from the substrate support 106. For example, the robot 170 may transport the substrate between the substrate support 106 and the load lock 172. Although shown as a separate controller, the temperature controller 142 may be mounted inside the system controller 160. In some examples, a protective seal 176 may be provided on the outer periphery of the bond layer 114 between the ceramic layer 112 and the base plate 110.

[0032] The substrate support 106 includes an edge ring 180. The edge ring 180 may be movable relative to the substrate support 106 (for example, movable vertically upward and downward). For example, the edge ring 180 may be controlled by actuators and lift pins in response to a system controller 160. In some examples, the system controller 160 and the robot 170 may further be configured to retrieve and replace the edge ring 180.

[0033] The system controller 160 according to this disclosure is configured to perform calibration of the robot 170, as described in more detail below. For example, the processing chamber 102 may include a removable lid 184. The lid 184 and the shower head 109 may be removable separately. In some examples, the shower head 109 or the upper electrode and gas distribution device may be integrated inside the lid 184 so that the shower head 109 also comes off the processing chamber 102 when the lid 184 is removed. During the calibration of the robot 170, a calibration jig (not shown in Figure 1, but described in more detail below) equipped with an imaging device (e.g., a camera) is attached to the processing chamber 102. The imaging device is positioned to measure the distance between the substrate 108 (e.g., a test substrate) and the edge ring 180 and calibrate the robot 170 accordingly.

[0034] Referring next to Figures 2A, 2B, and 2C, and subsequently to Figure 1, an exemplary calibration fixture 200 according to this disclosure comprises a plurality of imaging devices, such as cameras 202. For example, each camera 202 may correspond to a high-resolution charge-coupled device (CCD) camera array. In this example, the calibration fixture 200 comprises three cameras 202 arranged at 120 degrees apart, as shown in the plan view of Figure 2B.

[0035] The calibration fixture 200 is configured to be attached to the processing chamber 204 in place of the lid 184 in order to perform calibration of the robot 170. The calibration fixture 200 may be sealed to the processing chamber 204 using a seal (e.g., an O-ring) 206. The processing chamber 204 may be depressurized to a vacuum or other desired pressure for calibration. For example, the processing chamber 204 is depressurized to a vacuum pressure that matches the pressure during processing of substrates within it. Thus, measurements for performing calibration are performed while the processing chamber 204 is under vacuum and structural deflections caused by the vacuum pressure (e.g., vacuum deflections of various components and surfaces within the processing chamber 204) are present. In this way, the calibration of the robot 170 according to this disclosure more accurately corresponds to the conditions of the processing chamber 204 during the actual loading and unloading of substrates into and out of the processing chamber 204 for processing.

[0036] Each camera 202 is positioned to capture images of the outer edge of the test substrate 208 and the inner edge of the edge ring 212 within its respective camera field of view (FOV) 216. For example, the FOV 216 of each camera 202 is a rectangle of 18 × 22 mm. The captured images are then analyzed (e.g., by the system controller 160) to determine the distance between the edge of the test substrate 208 and the edge of the edge ring 212 in each image. The test substrate 208 may contain the same material (e.g., silicon) as the substrates processed in the processing chamber 204. Therefore, the properties, weight, and surface friction of the test substrate 208 under vacuum are consistent with those of a normal substrate processed in the processing chamber 204. The system controller 160 and / or its dedicated functional components are shown outside the calibration fixture 200 and cameras 202 in the figure, but in some examples they may be integrated inside one or more of the cameras 202, calibration fixture 200, etc.

[0037] In some examples, the test substrate 208 may have one or more reference markings 220 (e.g., lines coinciding with the radius of the test substrate 208) to facilitate analysis performed by the system controller 160. The test substrate 208 may further have notches 224 for determining the alignment / orientation of the test substrate 208 using a suitable substrate alignment system.

[0038] The calibration fixture 200 may further include one or more measuring devices 228 and 232 for measuring the distance between the calibration fixture 200, the test substrate 208 (and / or the top surface of the substrate support 236), and the edge ring 212, respectively. For example, the measuring devices 228 and 232 may implement a laser transmission sensor system. The system controller 160 may adjust the measurements performed for the calibration of the robot 170 to account for changes such as the height and tilt of the substrate support 236 and / or the edge ring 212. In some examples, the calibration fixture 200 may be equipped with a handle 240 to facilitate its mounting and removal.

[0039] In Figure 2C, the test board 208 is shown offset from the edge ring 212. The camera 202 captures images at each FOV 216, and the system controller 160 analyzes the images to determine the distances d1, d2, and d3 between each point on the outer perimeter of the test board 208 and the edge ring 212. In one example, the system controller 160 determines the coordinates (e.g., xy coordinates) of each point on the outer perimeter of the test board 208. For example, if the camera 202 is positioned at a known fixed position on the calibration fixture 200, each FOV 216 of the camera 202 corresponds to a known portion of the xy coordinate system. That is, by measuring the distances d1, d2, and d3, the corresponding coordinates of the three points on the outer edge of the test board 208 can be easily determined. The system controller 160 may then calculate the center 244 (e.g., xy coordinates) of the circumference corresponding to the test board 208 based on the distances d1, d2, and d3, as well as the coordinates of each point. For example, the x and y coordinates of the center 244 are calculated according to (x,y)=f(d1,d2,d3), where f(d1,d2,d3) is a function for calculating the center of the circumference using three known points on the circumference.

[0040] The center 248 of the edge ring 212 may be known (and / or may be calculated in the same way as the center 244 of the test board 208). The system controller 160 calculates correction amounts dR and dT based on the difference between the coordinates xy of the center 244 of the test board and the coordinates xy of the center 248 of the edge ring 212. For example, the correction amounts dR and dT may be calculated according to (dR,dT)=f(x,y,R,T), where R and T correspond to the target center position in the robot coordinate system. In other words, the system controller 160 relates the difference between the coordinates xy of the center 244 of the test board and the coordinates xy of the center 248 of the edge ring 212 to the correction amounts dR and dT applied to the target center positions R and T of the robot 170. The system controller 160 provides the robot 170 with the corrected R and T coordinates. The robot 170 can then retrieve the test board 208 and replace the test board 208 on the board support using the corrected R and T coordinates. The determination of the center 244 of the test board 208, correction of the R and T coordinates, and retrieval and replacement of the test board 208 may be repeated until the center 244 of the test board 208 coincides with the center 248 of the edge ring 212.

[0041] In an example where the test board 208 includes reference markings 220, the system controller 160 is configured to analyze captured images within each FOV 216 to compensate for mechanical tolerances related to relative positioning of the calibration fixture 200, camera 202, edge ring 212, etc. Figure 2D shows an exemplary reference marking 220 including reference lines 252 and reference squares 256. The reference lines 252 correspond to lines at each radius of the test board 208. Thus, the reference lines 252 interact with the center 244 of the test board 208. The system controller 160 analyzes the captured images to identify the reference lines 252 and measures the respective distances d from the endpoint of the reference lines 252 at the edge of the test board 208 to the edge ring 212. Based on the identified position of the reference lines 252 and the measured distances d1, d2, and d3, the system controller calculates the center 244 of the test board 208 (e.g., in the xy coordinate system).

[0042] Reference squares 256 are provided to calibrate the pixel size of the camera 202 within each FOV 216. For example, the reference squares 256 have a known width (e.g., 1 × 1 mm, 2 × 2 mm, etc.). As shown in the figure, the reference squares 256 include 1 × 1 mm squares and 2 × 2 mm squares. In other examples, two or more reference squares 256 may be provided. Furthermore, shapes other than the reference squares 256 may be used.

[0043] The system controller 160 analyzes the captured image to determine the number of pixels in each of the 256 reference squares. Since the size of the 256 reference squares is known, the width of each pixel can be determined accordingly. For example, if a 1×1mm reference square contains 116.46 pixels, the width of one pixel can be calculated as 1,000 / 116.46 or 8.587 microns. Similarly, if a 2×2mm reference square contains 234.313 pixels, the width of one pixel can be calculated as 2,000 / 234.313 or 8.536 microns. The distances d1, d2, and d3 can then be precisely measured based on the calculated width per pixel.

[0044] Referring now to Figure 3, an exemplary method 300 for calibrating a robot for a substrate processing system begins at 304. At 308, a calibration fixture is mounted in the processing chamber. For example, the calibration fixture includes one or more cameras positioned to capture images of areas of the processing chamber, including the edges and edge rings of the test substrate. At 312, the test substrate is transported to a substrate support in the processing chamber using the robot. At 316, the processing chamber is reduced to a vacuum pressure. At 320, the calibration fixture captures one or more images of the edges of the test substrate and the edges of adjacent edge rings (for example, in response to a controller such as a system controller 160). For example, the calibration fixture captures three images using each camera.

[0045] In step 324, method 300 analyzes the captured image (e.g., using the system controller 160) to determine the distance between the edge of the test board and the edge ring. In step 328, method 300 determines the center of the test board based on the determined distance (e.g., using the system controller 160). For example, method 300 determines the coordinates (e.g., in the xy-plane) of three points on the edge of the test board based on the determined distance and calculates the center of the test board accordingly. In step 332, method 300 determines (e.g., using the system controller 160) whether the calculated center of the test board coincides with the center of the edge ring. If true, method 300 determines that the robot calibration is complete and terminates in step 336. If false, method 300 continues to step 340.

[0046] In step 340, method 300 determines correction amounts dR and dT (e.g., using the system controller 160) to correct the R and T coordinates of the robot corresponding to the nominal center point. For example, method 300 determines the correction amounts dR and dT based on the difference between the calculated center of the test board and the center of the edge ring. In step 344, method 300 updates the R and T coordinates of the robot according to the determined correction amounts. In step 348, method 300 controls the robot (e.g., using the system controller 160) to retrieve and replace the test board using the corrected R and T coordinates. Method 300 then repeats steps 320 through 332, following step 320, until calibration is complete (i.e., until the calculated center of the test board coincides with the center of the edge ring).

[0047] Referring next to Figures 4A, 4B, 4C, and 4D, illustrations of an exemplary calibration fixture 400 according to the present disclosure are shown. In Figure 4D, the calibration fixture 400 is shown mounted on an exemplary processing chamber 404. The calibration fixture 400 comprises a bottom cover plate 408 configured to rest on the upper end of the processing chamber 404. For example, the cover plate 408 may have bolt holes configured to receive mounting bolts, each coinciding with a hole in the processing chamber 404. The cover plate 408 may have grooves 416 configured to compress and hold an annular seal, such as an O-ring, between the cover plate 408 and the processing chamber 404. The bottom surface of the cover plate 408 comprises openings 420 corresponding to each camera of the camera 424. The camera 424 is positioned between the bottom cover plate 408 and the upper plate 428 of the calibration fixture 400.

[0048] The foregoing is essentially illustrative and is by no means intended to limit the Disclosure, its application, or its use. The broad teachings of this Disclosure can be implemented in various forms. Therefore, although this Disclosure includes certain examples, the true scope of this Disclosure should not be so limited, as other modifications will become apparent when considering the drawings, specification, and the claims below. It should be understood that one or more steps within a Method may be performed in a different order (or simultaneously) without altering the principles of this Disclosure. Furthermore, although each embodiment is described above as having certain features, any one or more of those features described in relation to the embodiments of this Disclosure may be implemented in other embodiments and / or in combination with features of other embodiments (even if such combination is not specified). In other words, the embodiments described are not mutually exclusive, and rearrangements of one or more embodiments remain within the scope of this Disclosure.

[0049] The spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.) are described using a variety of terms, including “connected,” “engaged,” “joined,” “adjacent,” “proximity,” “above,” “upward,” “downward,” and “positioned.” When a relationship between a first element and a second element is described in the above disclosure, unless it is explicitly stated to be “direct,” the relationship may be a direct relationship in which no other intervening elements exist between the first and second elements, but at the same time, it may be an indirect relationship in which one or more intervening elements (spatially or functionally) exist between the first and second elements. The expression “at least one of A, B, and C” as used herein should be interpreted as meaning the logic using the non-exclusive logic OR (A OR B OR C), and not as “at least one of A, at least one of B, and at least one of C.”

[0050] In some embodiments, the controller is part of a system which may be part of the examples described above. Such a system may include a semiconductor processing apparatus comprising a processing tool, a chamber, a processing platform, and / or specific processing components (such as a wafer pedestal, a gas flow system, etc.). These systems may be integrated with electronic equipment for controlling pre-processing, processing, and post-processing operations of semiconductor wafers or substrates. These electronic equipment may be referred to as “controllers” and may control various components or sub-components of the system. Depending on the processing conditions and / or the type of system, the controller may be programmed to control any of the processes disclosed herein, including the supply of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid supply settings, position operation settings, wafer loading and unloading to and from tools and other transport tools, and / or wafer loading and unloading to and from load locks connected to or coupled to a particular system.

[0051] Generally, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive and issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. An integrated circuit may include a firmware-type chip that stores program instructions, a chip defined as a digital signal processor (DSP), an application-specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions are instructions that are transmitted to the controller in the form of various individual settings (or program files) and may define operating parameters for executing a particular process on or for a semiconductor wafer or for a system. In some embodiments, the operating parameters may be part of a recipe defined by a process engineer to realize one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or one or more processing steps during the manufacturing of a wafer die.

[0052] In some embodiments, the controller may be part of a computer integrated with or coupled to the system, or otherwise networked to the system, or a combination thereof, or coupled to such a computer. For example, the controller may reside in a “cloud” enabling remote access to wafer processing, or may be all or part of a fab host computer system. The computer may enable remote access to the system to monitor the progress of manufacturing operations, review the history of past manufacturing operations, examine trends or performance criteria from multiple manufacturing operations, modify parameters of the current operation, set up subsequent processing steps for the current operation, or start a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system via a network that may include a local network or the internet. The remote computer may include a user interface that enables the entry or programming of parameters and / or settings that are then transmitted from the remote computer to the system. In some examples, the controller receives instructions in a data format that specify the parameters of each processing step performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool that the controller is configured to connect to or control. Therefore, as described above, the controllers may be distributed by, for example, including one or more separate controllers that are networked together and by cooperating toward a common purpose, such as the processes and control described herein. An example of controllers distributed toward such a purpose would be one or more integrated circuits on a chamber that are located remotely (for example, at the platform level or as part of a remote computer) and communicate with one or more integrated circuits that cooperate to control the processes in the chamber.

[0053] Rather than being limiting, the exemplary systems may include plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and other semiconductor processing systems that may be related to or used in the fabrication and / or manufacture of semiconductor wafers.

[0054] As described above, the controller may communicate with one or more of the following, depending on the processing steps performed by the tool: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools installed throughout the factory, a main computer, another controller, or tools used for material handling to load and unload wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing plant.

Claims

1. 1. A robot calibration system comprising: a calibration fixture configured to be attached to a substrate processing chamber, the calibration fixture comprising at least one camera positioned to capture an image including an outer edge of a test substrate and an edge ring surrounding the test substrate; a controller configured to receive the captured image, analyze the captured image to measure a distance between the outer edge of the test substrate and the edge ring, calculate a center of the test substrate based on the measured distance, and calibrate a robot configured to transfer substrates into and out of the substrate processing chamber based on the calculated center of the test substrate; A robot calibration system comprising:

2. 10. The robot calibration system of claim 1, The at least one camera corresponds to three cameras.

3. 10. The robot calibration system of claim 1, the robot calibration system comprising a seal compressed between the calibration fixture and the substrate processing chamber, and the controller configured to pump the substrate processing chamber to a vacuum while the calibration fixture is attached to the substrate processing chamber.

4. 4. The robot calibration system of claim 3, The controller is configured to control the at least one camera to capture the image while the substrate processing chamber is under vacuum.

5. 10. The robot calibration system of claim 1, the controller is configured to determine a width of a pixel in a field of view of the at least one camera and measure the distance between the outer edge of the test substrate and the edge ring based on the determined width of the pixel.

6. 6. The robot calibration system of claim 5, the test substrate includes at least one fiducial marking located in the field of view of the at least one camera, the at least one fiducial marking having a known dimension, and the controller is configured to determine the width of the pixel based on the known dimension.

7. 7. The robot calibration system of claim 6, The at least one fiducial marking is a square, and the known dimension is a width of the square.

8. 10. The robot calibration system of claim 1, the test substrate includes a reference line that corresponds to a radius of the test substrate, and the controller is configured to measure the distance between the outer edge of the test substrate and the edge ring at a position corresponding to the reference line.

9. 10. The robot calibration system of claim 1, The robot calibration system, wherein the controller is configured to calculate a correction amount based on the calculated center of the test substrate and calibrate the robot based on the correction amount.

10. 10. The robot calibration system of claim 9, The robot calibration system, wherein the controller is configured to calculate the correction based on an offset between the calculated center of the test substrate and a center of the edge ring.

11. 10. The robot calibration system of claim 1, A robot calibration system, wherein the robot is calibrated by updating a plurality of coordinates of the robot.

12. 1. A method for calibrating a robot configured to transfer substrates into and out of a substrate processing chamber, the substrate processing chamber having a calibration fixture mounted thereon, the calibration fixture having at least one camera, the method comprising: capturing an image with the at least one camera that includes an outer edge of a test substrate and an edge ring surrounding the test substrate; analyzing the captured image to measure the distance between the outer edge of the test substrate and the edge ring; calculating the center of the test substrate based on the measured distance; calibrating the robot based on the calculated center of the test substrate; A method comprising:

13. 13. The method of claim 12, The method, wherein the at least one camera corresponds to three cameras.

14. 13. The method of claim 12, further comprising: The method includes pumping the substrate processing chamber to a vacuum.

15. 15. The method of claim 14, further comprising: controlling the at least one camera to capture the image while the substrate processing chamber is under vacuum.

16. 13. The method of claim 12, further comprising: determining a width of a pixel in a field of view of the at least one camera; and measuring the distance between the outer edge of the test substrate and the edge ring based on the determined width of the pixel.

17. 17. The method of claim 16, the test substrate includes at least one fiducial marking located in the field of view of the at least one camera, the at least one fiducial marking having a known dimension, and the width of the pixel is determined based on the known dimension.

18. 18. The method of claim 17, The method, wherein the at least one fiducial marking is a square and the known dimension is a width of the square.

19. 13. The method of claim 12, The method, wherein the test substrate includes a reference line coinciding with a radius of the test substrate, and the distance between the outer edge of the test substrate and the edge ring is measured at a location corresponding to the reference line.

20. 13. The method of claim 12, further comprising: calculating a correction based on the calculated center of the test substrate; and calibrating the robot based on the correction.

21. 21. The method of claim 20, further comprising: calculating the correction based on an offset between the calculated center of the test substrate and a center of the edge ring.

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