System and method for automatically correcting substrate misalignment

Abstract

Embodiments described herein relate to semiconductor fabrication and processing. More specifically, a processing system for automatically correcting misalignment of a substrate in a processing chamber is provided. A processing system includes a processing chamber having a substrate support disposed within a chamber volume of the processing chamber. The substrate support includes a pocket for receiving a substrate and a plurality of flow conduits extending between a top surface of the pocket and a bottom surface of the substrate support. An imaging device is coupled to the processing chamber and is configured to monitor a position of the substrate when loaded in the pocket of the substrate support.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to semiconductor manufacturing and processing. More specifically, the present disclosure relates to systems and methods for automatically correcting misalignment of a substrate in a processing chamber. Background Art

[0002] In semiconductor device manufacturing processes such as CVD, epitaxy, or other thermal processes, substrates are typically processed in chambers or other processing equipment. In order to process the substrate in the chamber, the substrate is securely attached to a substrate support in the chamber to mitigate movement of the substrate during processing. If the substrate moves during processing, the substrate may become misaligned. Factors that may cause the substrate to become misaligned include gas flow, pressure, and temperature around the substrate support during processing. If the substrate becomes misaligned, the uniformity of thickness and / or film properties may be adversely affected.

[0003] Some semiconductor device manufacturing processing systems can transfer substrates between multiple chambers, each chamber having a substrate support structure, such as a deposition device, an etching device, an inspection device, or the like. The substrate can be transferred between chambers by a transfer arm having a fork or an end effector. This substrate exchange process may cause the positioning of the substrate relative to the substrate support to shift and become misaligned. When the substrate support structure within the processing system is not properly aligned, the support structure will not hold the substrate at approximately the same tilt or inclination. Therefore, when one support structure transfers the substrate to another support structure, such as when the lifting pin removes the substrate from the blade of the transfer chamber substrate processor or places the substrate on the substrate support in the processing chamber, one point of the substrate is likely to contact the receiving support structure before other points contact the receiving support structure. If substantial movement occurs before the remaining points make contact, the substrate may move. In this way, potential contamination particles may be scraped off from the contact point of the substrate, resulting in backside contamination of the substrate. These particles may eventually go around the top of the substrate and deposit on the processing surface of the substrate, thereby contaminating the microcircuitry or other structures built thereon. Furthermore, when the substrate does not contact the receiving support structure with very close alignment at all points, the substrate may shift from its proper or intended position, causing the substrate to be off-center. In addition, temperature differences between the substrate and the substrate support may cause thermal shock, such that the substrate may warp. Warping of the substrate may also cause the substrate to shift and become misaligned. As described above, an off-center substrate may experience uneven or incorrect processing, or may come into contact with surfaces or objects within the processing system, which may contaminate the substrate, generate particles that potentially contaminate the air, or even damage the substrate.

[0004] Figure 1The need for placement accuracy is shown in . Therein, a typical substrate 10 and a substrate support, such as a pedestal 12 for holding the substrate 10 in a single substrate processing chamber, are described. For a given substrate 10, the recess on the substrate receiving surface of the pedestal 12 that receives the substrate 10 typically has a diameter that is only slightly larger than the diameter of the substrate 10. There is typically a small gap 14 between the edge of the substrate 10 and the edge of the recess of the pedestal 12. The substrate 10 is centered in the recess and a gap is maintained between the edge of the substrate 10 and the sidewalls of the recess. If the substrate 10 contacts the sidewalls of the recess, local temperature changes occur, resulting in a temperature gradient across the substrate 10. This can lead to non-uniform processing results because most semiconductor processing relies heavily on temperature. Similarly, in many different processing situations, a misaligned or miscentered substrate may be damaged during placement.

[0005] Substrate misalignment may occur before or during processing of a substrate in a processing chamber. As described above, substrate misalignment may lead to non-uniformity in processing results. Therefore, when substrate misalignment is detected, such misalignment should be corrected in a timely manner to avoid non-uniform or incorrect processing of the substrate.

[0006] Therefore, a need exists for a system and method for monitoring and automatically correcting the position of a substrate when misalignment of the substrate is detected. Summary of the invention

[0007] Embodiments of the present disclosure relate generally to semiconductor manufacturing and processing. More specifically, embodiments disclosed herein relate to processing systems and methods for automatically correcting misalignment of a substrate in a processing chamber.

[0008] In some embodiments, a processing system for automatically centering a substrate in a processing chamber is provided. The processing system includes a processing chamber having: a substrate support disposed within a chamber volume of the processing chamber. The substrate support includes a recess for receiving the substrate; and a plurality of flow conduits extending between a top surface of the recess and a bottom surface of the substrate support. An imaging device is coupled to the processing chamber and is configured to monitor a position of the substrate when loaded in the recess of the substrate support.

[0009] In some embodiments, a processing system for automatically centering a substrate in a processing chamber is provided. The processing system includes a processing chamber having a susceptor and a preheat ring disposed within a chamber volume of the processing chamber. The susceptor includes a recess for receiving the substrate, and the preheat ring radially overlaps the susceptor. A plurality of conduits extend through portions of the susceptor, and an imaging device is coupled to the processing chamber and configured to monitor a substrate in the recess of the susceptor.

[0010] In some embodiments, a method of automatically centering a substrate in a processing chamber is provided. The method includes detecting a misalignment of a substrate loaded on a substrate support disposed in a chamber volume of the processing chamber. The method includes determining a recommended adjustment to correct the misalignment based on the misalignment, and providing a gas flow from the chamber volume to the substrate support based on the recommended adjustment. The method includes detecting a corrected position of the substrate on the substrate support, wherein the corrected position corresponds to a center position of the substrate support. And the method includes stopping the gas flow to the substrate support to position the substrate on the substrate support in a correct position. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Thus, the above-mentioned features of the present disclosure can be understood in detail, and a more specific description of the present disclosure, briefly summarized above, can be made by reference to the embodiments, some of which are depicted in the accompanying drawings. However, it should be noted that the drawings only illustrate exemplary embodiments and are therefore not to be considered limiting of its scope, and other equally effective embodiments may be allowed.

[0012] Figure 1 is a schematic diagram in top view and cross-section showing a 200 mm substrate seated in a pocket of a substrate holder of a pedestal in accordance with certain embodiments of the present disclosure.

[0013] Figure 2 An example processing system that may be used to implement the processing methods described herein according to certain embodiments of the present disclosure is schematically illustrated.

[0014] Figure 3 is a method for detecting Figure 2 A flow chart of an example method for processing misalignment of a substrate in a system of FIG.

[0015] Figure 4 According to some embodiments of the present disclosure, Figure 2 A cross-sectional view of an example base in the processing system of A.

[0016] Figure 5 According to some embodiments of the present disclosure, Figure 2 Flowchart of an example method for automatically correcting misalignment of a substrate on a susceptor.

[0017] Fig. 6A and 6B According to some embodiments of the present disclosure, Figure 2 A cross-sectional view of an example base in a processing system.

[0018] Figure 7 is a flow chart illustrating an example method for automatically correcting misalignment of a substrate on the pedestal of FIG. 6 , according to certain embodiments of the present disclosure.

[0019] Fig. 8Aand 8B According to some embodiments of the present disclosure, Figure 2 A is a schematic diagram of an example base used in the processing system.

[0020] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0021] The present disclosure relates generally to semiconductor manufacturing and processing. More specifically, the present disclosure relates to systems and methods for automatically correcting misalignment of a substrate on a substrate support (eg, a susceptor).

[0022] Processing systems for processing substrates are generally known. Typically, such processing systems have a central transfer chamber mounted on an integral platform. The transfer chamber is the active center of movement of substrates being processed in the system. One or more processing chambers are mounted on the transfer chamber at slit valves through which substrate handlers or robots transfer substrates. Access to the transfer chamber from a clean ambient environment is typically through one or more load lock chambers attached to other slit valves. The load lock chamber may be open to a clean room, referred to as a white zone, or may be open to an optional substrate processing chamber, generally referred to as a micro environment.

[0023] Figure 2 1 is a schematic cross-sectional view of a processing system 100 that can be used to practice the processing methods described herein. Here, the processing system 100 is configured to automatically correct the positioning of the substrate 108 on a substrate support, such as a susceptor 106 in a processing chamber 101 when misalignment of the substrate 108 on the susceptor 106 is detected. The processing chamber 101 can be used to process one or more substrates, including depositing a material on an upper surface of the substrate 108 (which can be similar to the substrate 10, for example).

[0024] The processing chamber 101 may include a susceptor 106 (eg, which may be a Figure 1 The pedestal 106 may be provided with an array of radiant heating lamps 102 disposed on the back side 104 of the pedestal 12 shown. In some embodiments, the array of radiant heating lamps may be placed above the upper dome 128. The pedestal 106 may be a disk-shaped pedestal 106 as shown, or may be a ring-shaped pedestal without a central opening that supports the substrate from its edge to facilitate exposure of the substrate to the heat radiation of the lamps 102.

[0025] The susceptor 106 is located within the processing chamber 101 between the upper dome 128 and the lower dome 114. The upper dome 128, the lower dome 114, and the base ring 136 disposed between the upper dome 128 and the lower dome 114 generally define an interior region of the processing chamber 101. A substrate 108 (not to scale) may be brought into the processing chamber 101 and positioned onto the susceptor 106 through the load port 103.

[0026] The pedestal 106 is shown in an elevated processing position, but may be vertically advanced by an actuator (not shown) to a loading position below the processing position to allow the lift pins 105 to contact the lower dome 114, pass through the holes in the pedestal 106 and the central shaft 132, and lift the substrate 108 from the pedestal 106. A robot (not shown) may then enter the processing chamber 101 to engage and remove the substrate 108 from the load port 103. The pedestal 106 may then be actuated to the processing position to place the substrate 108 on the front side 110 of the pedestal 106 with the device side 116 of the substrate facing upward.

[0027] The susceptor 106, when in the processing position, divides the interior chamber volume 123 of the processing chamber 101 into a process gas region 156 above the substrate and a purge gas region 158 below the susceptor 106. The susceptor 106 is rotated by the central axis 132 during processing to minimize the effects of thermal and process gas flow spatial anomalies within the processing chamber 101 and, therefore, promote uniform processing of the substrate 108. The susceptor 106 is supported by the central axis 132, which moves the substrate 108 in an up and down direction 134 during loading and unloading of the substrate 108 and, in some cases, during processing of the substrate 108. The susceptor 106 may be formed of silicon carbide or graphite coated with silicon carbide to absorb radiant energy from the lamps 102 and conduct the radiant energy to the substrate 108.

[0028] Generally, the central window portion of the upper dome 128 and the bottom of the lower dome 114 are formed of an optically transparent material such as quartz. Here, "optically transparent" means that radiation is generally transparent, but not necessarily 100% transparent. As will be described below with reference to Figure 2 As discussed in greater detail, the thickness and curvature of the upper dome 128 may be configured in accordance with the present invention to provide a flatter geometry to achieve uniform flow uniformity within the processing chamber.

[0029] One or more lamps, such as an array of lamps 102, may be positioned proximate to and below the lower dome 114 in a designated optimally desired manner about the central axis 132 to independently control the temperature at various regions of the substrate 108 as process gases pass therethrough, thereby facilitating deposition of material onto the upper surface of the substrate 108. Although not discussed in detail herein, the deposited material may include gallium arsenide, gallium nitride, or aluminum gallium nitride.

[0030] The lamps 102 may be configured to include a bulb 141 and to heat the substrate 108 to a temperature in the range of about 200 degrees Celsius to about 1600 degrees Celsius. Each lamp 102 is coupled to a power distribution board (not shown) through which power is supplied to each lamp 102. The lamps 102 are located within a lamp head 145, which may be cooled during or after processing by, for example, a cooling fluid introduced into a channel 149 located between the lamps 102. The lamp head 145 cools the lower dome 114 by conduction and radiation, in part due to the close proximity of the lamp head 145 to the lower dome 114. The lamp head 145 may also cool the walls of the lamp and the walls of a reflector (not shown) surrounding the lamp. Alternatively, the lower dome 114 may be cooled by convection. Depending on the application, the lamp head 145 may or may not be in contact with the lower dome 114.

[0031] A circular shield 167 may be optionally disposed around the pedestal 106 and surrounded by the gasket assembly 163. The shield 167 prevents or minimizes thermal / optical noise from leaking from the lamp 102 to the device side 116 of the substrate 108 while providing a preheating zone for the process gases. The shield 167 may be made of CVD SiC, sintered graphite coated with SiC, grown SiC, opaque quartz, coated quartz, or any similar suitable material that resists chemical decomposition by process and purge gases.

[0032] The liner assembly 163 is sized to be nested within or surrounded by the inner periphery of the base ring 136. The liner assembly 163 shields the chamber volume 123 (i.e., the process gas region 156 and the purge gas region 158) from the metal walls of the processing chamber 101. The metal walls may react with the precursors and cause contamination in the chamber volume 123. Although the liner assembly 163 is shown as a single body, the liner assembly 163 may include one or more liners having different configurations.

[0033] As a result of the backside heating of the substrate 108 from the susceptor 106, it is feasible to use the optical pyrometer 118 to measure / control the temperature on the susceptor. Such temperature measurement by the optical pyrometer 118 can also be done on the substrate device side 116 with unknown emissivity, because heating the substrate front side 110 in this manner is independent of emissivity. As a result, the optical pyrometer 118 can only sense radiation from the hot substrate 108 that is conducted from the susceptor 106, with minimal background radiation from the lamp 102 reaching the optical pyrometer 118 directly.

[0034] The reflector 122 may be selectively placed outside the upper dome 128 to reflect infrared light radiated from the substrate 108 back onto the substrate 108. The reflector 122 may be fixed to the upper dome 128 using a clamp ring 130. The reflector 122 may be made of a metal such as aluminum or stainless steel. The reflective efficiency may be improved by coating a highly reflective coating (e.g., gold) on the reflector area. The reflector 122 may have one or more conduits 126 connected to a cooling source (not shown). The conduit 126 is connected to a passage (not shown) formed on one side of the reflector 122. The passage is configured to carry a fluid flow such as water and may extend horizontally along the side of the reflector 122 in any desired pattern covering a portion or the entire surface of the reflector 122 for cooling the reflector 122.

[0035] Process gas supplied from a process gas supply source 172 is introduced into the process gas region 156 through a process gas inlet 174 formed in a sidewall of the base ring 136. The process gas inlet 174 is configured to direct the process gas in a generally radially inward direction. During the film formation process, the susceptor 106 can be located in a processing position adjacent to and at about the same height as the process gas inlet 174 so that the process gas can flow upward and around the upper surface of the substrate 108 along the flow path 173 in a laminar manner. The process gas leaves the process gas region 156 (along the flow path 175) through a gas outlet 178 located on a side of the process chamber 101 opposite the process gas inlet 174. Removal of the process gas through the gas outlet 178 can be facilitated by a vacuum pump 180 connected to the gas outlet 178. Because the process gas inlet 174 and gas outlet 178 are aligned with each other and disposed at substantially the same height, it is believed that this parallel arrangement, when combined with the flatter upper dome 128 (as discussed in detail below), will enable a generally planar, uniform gas flow across the substrate 108. Further radial uniformity may be provided by rotating the substrate 108 through the pedestal 106.

[0036] The purge gas supplied from the purge gas supply source 162 is introduced into the purge gas region 150 through the purge gas inlet 164 formed in the side wall of the base ring 136. The purge gas inlet 164 may be disposed at a height below the susceptor 106, thereby allowing the purge gas to flow downward and around the bottom surface of the susceptor 106 along the flow path 165. The purge gas may be an inert gas, such as hydrogen or nitrogen. The flow of the purge gas in the purge gas region 158 helps prevent or reduce the flow of the process gas or the diffusion of the process gas from the process region 156 above the susceptor 106 to the purge gas region 158 below the susceptor 106. The purge gas leaves the purge gas region 158 through the gas outlet 179. Alternatively, the purge gas region 158 may further include a vent (not shown) for discharging the purge gas directly from the purge gas region 158 into the gas outlet 178. The vacuum pump 180 also helps to exhaust the purge gas through the gas outlet 179.

[0037] As described above, the substrate 108 may become misaligned on the substrate receiving surface of the susceptor 106 (e.g., due to degradation or other factors) and / or the susceptor 106 may become misaligned and may be unevenly rotated, tilted, or off-center. Such misalignments may result in uneven processing of the substrate 108. In order to detect such misalignments by the processing system 100 for automatic correction, a position detection device, such as a camera 200, may be employed in the processing system 100 and coupled to the processing chamber 101.

[0038] like Figure 2 As shown, the processing chamber 101 may include a camera 200 for monitoring the position of the substrate 108 and detecting misalignment of the substrate 108 on the susceptor 106 and subsequent correction. The camera 200 may be communicatively coupled to a controller 202, which controls the operation of the camera 200 (e.g., on / off, focus, image acquisition, etc.). In some embodiments, the controller 202 is communicatively coupled to a central processing unit (CPU) 204. The controller 202 may download a program stored in a storage medium through an input / output (I / O) device (not shown), and implement the position detection method described below by controlling the camera 200 according to the program.

[0039] In one embodiment, Figure 1As shown, the camera 200 can be located above the top of the processing chamber 101, and a collection device for the camera, such as a light pipe, can be set through the top of the processing chamber 101 into the processing gas region 156. Alternatively, the camera 200 can be located inside the processing chamber 101. For example, the camera 200 can be set in the opening 186 in the upper dome 128 between the upper dome 128 and the reflector 122. The camera 200 or the collection device of the camera can be set through the inlet for connecting the conduit 126 to the processing chamber 101, or alternatively, the camera 200 can be coupled to the chamber using a chassis. The camera 200 can operate under vacuum or atmospheric pressure. The camera 200 can be in the processing chamber 101 to capture images of the substrate 108, edge ring, mask, and / or pedestal 106. The position of the camera 200 relative to the upper dome 128 and the pedestal 106 and the optical characteristics of the camera 200 may be determined to ensure a field of view that includes the edge of the substrate 108, the edge ring, the mask, and / or the pedestal 106 for position detection.

[0040] The camera 200 is just one example of a device that can be used for imaging, and any other type of imaging device can be used as a positioning detection device. In an embodiment, more than one camera can be used to capture images of the substrate 108, edge ring, mask, and / or base 106. In an embodiment, the camera 200 is an image capture device, which can be a high-efficiency, low-voltage complementary metal oxide semiconductor (CMOS) sensor that is used as a single-chip video camera. The CMOS sensor can be a VGA type. The camera 200 can include a lens, such as a wide-angle lens or a plano-convex lens with an appropriate focal length to provide sufficient visual clarity within the expected operating range of the camera 200. It is obvious to those skilled in the art that different lenses (e.g., telescopic or rotating prism lenses) can be used for different applications. It should also be understood that other types of cameras or optical sensors can be utilized, including but not limited to SVGA, XGA, MEGA pixel type cameras or other image capture devices. If desired, multiple image capture devices with different types of resolutions can be used in combination with lenses of different types and focal lengths. The camera or sensor can be a static (fixed) or dynamic (video) type, and can be a charge coupled device (CCD) type. Alternatively, the camera can be used to output the video signal to any standard television format.

[0041] Figure 3 300 is a flow chart illustrating example operations 300 for detecting misalignment of an object in a processing system according to certain embodiments of the present disclosure. At 302, an image of an object may be obtained. The object may be a substrate, a mask, an edge, a base, etc. The image may be obtained using a high-resolution video camera (e.g., CMOS, SVGA, XGTA, or MEGA pixel type). According to certain embodiments, the image may be obtained while the object is rotating.

[0042] At 304, values ​​(eg, RGB values) associated with pixels in at least one region of the image may be determined. These values ​​may be from the original image or a filtered image.

[0043] At 306, misalignment of the object may be detected based on these values. According to some embodiments, detection of misalignment of the object may include blocks 306A and 306B. For example, at 306A, at least one of the following may be calculated: a center of gravity value of pixels in a region or an average weight of pixels in a region, and at 306B, misalignment of the object may be detected based on at least one of the following: the calculated center of gravity value or the average weight of pixels in a region.

[0044] According to some embodiments, operation 300 may further include obtaining a second image of the object after obtaining the first image (e.g., at a later time). Values ​​associated with pixels in at least one region of the second image may be determined and compared to values ​​associated with pixels in at least one region of the first image that have been determined. Detection of object misalignment may be further performed based on the comparison (e.g., by observing how centroid values ​​and / or average weights of pixels in at least one region change from the first image to the second image).

[0045] According to certain embodiments, the detected misalignment value may be output to allow correction of the misalignment. In one embodiment, the detected misalignment may be output to a feedback system for determining a recommended adjustment to the substrate to correct the misalignment. The feedback system may then initiate a process to move the position of the substrate on the base and correct the misalignment based on the determined recommended adjustment. In some embodiments, the recommended determined adjustment may displace the position of the substrate in the recess of the base by between about 0.1 mm and about 0.5 mm. Additionally or alternatively, the misalignment value may be stored in a memory connected to the optical imaging device. If output on a screen, monitor, printout, or the like, the center of gravity value and weight may be output as a signal and monitored for vibration, which may indicate misalignment.

[0046] Additional information regarding systems and methods for detecting substrate misalignment can be found, for example, in U.S. Patent No. 9,959,610.

[0047] Once misalignment of the substrate 108 on the susceptor 106 is detected, the misalignment of the substrate 108 may be corrected, thereby preventing errors in substrate manufacturing or processing.

[0048] Figure 4 According to some embodiments of the present disclosure, Figure 14 is a cross-sectional view of an example pedestal 400 in a processing chamber 101 of FIG. As described above, a substrate 108 may be brought into the chamber volume 123 of the processing chamber 101 and positioned within a recess 404 on a substrate receiving surface 403 of the pedestal 400 for processing of the substrate 108.

[0049] In an embodiment, Figure 4 As shown, the pedestal 400 includes a plurality of flow conduits 402 disposed therein in fluid connection with the purge gas region 158 below the pedestal 106. The plurality of flow conduits 402 described herein can direct a gas flow from the purge gas region 158 to a portion of a pocket 404 of the pedestal 400 and any substrate 108 positioned in the pocket therein. The flow of gas through the flow conduits 402 at any substrate 108 positioned in the pocket 404 therein can be configured such that the pressure from the gas is sufficient to lift the substrate 108 and move the substrate 108. The plurality of flow conduits 402 can be communicatively coupled to and controlled by the feedback system described herein.

[0050] The feedback system can be connected between the plurality of flow conduits 402 in the pedestal 400, the controller 202, and the camera 200 so that the plurality of flow conduits 402 operate by responding to misalignment and correction of the position of the substrate detected by the camera 200. As described above, the feedback system can use the camera 200 to actively monitor the position of the substrate 108 within the cavity 404 to detect misalignment of the substrate 108 on the pedestal 106, and determine when the misalignment has been corrected after initiating a substrate movement program. When misalignment of the substrate 108 on the pedestal 106 is detected, the feedback system can then initiate an automatic correction program to move the substrate 108 and correct the misalignment by providing a gas flow through the plurality of conduits 402. The feedback system can also use the controller 202 to control each flow valve 412 to start and stop the flow of gas through the plurality of flow conduits 402 to control the flow of gas into the cavity 404.

[0051] In some embodiments, each of the plurality of flow conduits 402 includes an inlet opening 408 at a bottom surface 413 of the base 400, which is in fluid communication with an outlet opening 410 at a top surface 414 of the recess 404 of the base 400. In one embodiment, the outlet opening 410 may be positioned near the outer edge of the recess 404 so that the airflow passing through the flow conduit 402 can be directed toward the bottom edge 111 and the bottom surface 109 of the substrate 108 in the recess 404. The outlet opening 410 may also be formed along the inner sidewall of the recess 404 so that the airflow from the corresponding outlet opening 410 can be directed on the side of the substrate 108. Alternatively, the outlet opening 410 may be provided on any other portion of the recess 404 so that the airflow can be directed from the surface 414 to any portion of the substrate 108. In another embodiment, the size of the outlet opening 410 in each of the plurality of flow conduits 402 may be generally the same. Alternatively, the size of the outlet opening 410 may also be varied to provide a greater airflow to certain portions of the recess 404.

[0052] In another embodiment, each of the plurality of flow conduits 402 may further include a controllable flow valve 412 to control the respective flow rate of gas passing through each of the plurality of flow conduits 402. In an embodiment, each of the flow valves 412 of the plurality of flow conduits 402 may be communicatively coupled to the controller 202 and the camera 200 in a feedback system. The feedback system may also be connected to the CPU 204 for misalignment detection and correction detection by the camera 200. The CPU 204 may also be communicatively coupled to the base 400 and may be capable of determining a recommended adjustment when a misalignment is detected. The CPU 204 may provide instructions to the controller 202 to control the flow valves 412 of the plurality of flow conduits 402 based on the recommended adjustment to start and stop the gas flow through the flow conduits 402.

[0053] The plurality of flow valves 412 in the pedestal 400 are communicatively coupled to the controller 202, which can dynamically control the operation (e.g., opening and closing) of the flow valves 412 in the feedback system. When it is desired to move the substrate 108 (e.g., to correct a detected misalignment), the flow valves 412 are opened to allow gas from the purge gas region 158 below the pedestal 106 to enter and flow through the conduits 402 to the pockets 404 on the substrate receiving surface 403 of the pedestal 400. When the flow valves 412 are open, the gas flowing through the plurality of flow conduits 402 described herein can be capable of lifting the substrate 108 off the surface 403 of the pocket 404 and moving the substrate 108 along the horizontal XY plane of the pocket 404 using the pressure of the gas flowing from the flow conduits 402. In one embodiment, the flow valves 412 can be controlled to selectively flow gas through certain flow conduits 402 based on the direction of desired movement of the substrate 108. When the feedback system initiates an automatic correction procedure to move and correct the misalignment of the substrate 108, the plurality of flow valves 412 to be opened by the feedback system may be activated together, individually, and / or sequentially in response to the movement of the substrate 108 to correct the detected misalignment and center the substrate 108 in the pocket 404. In another embodiment, the flow valves 412 may be configured as fixed flow valves that can be controlled by the feedback system to dynamically adjust and set the pressure of the gas flowing through the flow conduit 402 to control the amount of force applied to the substrate 108.

[0054] In certain embodiments, the control of the flow valves 412 is coupled to a feedback system to move the substrate 108 when misalignment of the substrate 108 is detected. The feedback system can be connected between the camera 200 that monitors the position of the substrate 108 and the plurality of flow valves 412, such that the flow valves 412 selectively operate in response to the misalignment of the substrate 108 detected by the camera 200 to correct the detected misalignment. As discussed herein, the feedback system uses the camera 200 to detect misalignment of the substrate 108 in the pocket 404 of the pedestal 106. Based on the misalignment of the substrate 108 detected by the camera 200, the feedback system determines a recommended adjustment to properly center the substrate 108 in the pocket 404. The feedback system then selectively controls the flow valves 412 to provide gas flow through certain flow conduits 402 to enable and direct gas at certain portions of the substrate 108 to move the substrate 108 along the horizontal XY plane of the pocket 404 based on the recommended adjustment.

[0055] For example, if the recommended adjustment includes moving substrate 108 to the right of its current position, the feedback system may open flow valves 412 of flow conduits 402 proximate the relatively left side of substrate 108 to apply airflow against the left side of substrate 108 and push substrate 108 to the right.

[0056] Figure 5 is a diagram showing a method for when the substrate 108 is disposed in a Figure 4 Flowchart of example operations of a method 500 for automatically correcting misalignment of a substrate 108 by a processing system 100 when on a pedestal 400. The method 500 begins at 502 by detecting misalignment of a substrate 108 with a center position of a cavity 404 of a pedestal 400 in the processing system 100.

[0057] At 504, upon detecting a misalignment of the substrate 108, the processing system 100 determines a recommended adjustment to correct the detected misalignment and move the substrate 108 to a center position of the well 404. The recommended adjustment may be determined based on a first position of the substrate 108 from which the misalignment was detected by the camera 200.

[0058] At 506, the processing system 100 provides a gas flow to the pocket 404 of the pedestal 400 based on the recommended adjustments to move the substrate 108 along the horizontal XY plane of the pocket 404. In one embodiment, the gas is provided through the plurality of flow conduits 402 flowing through the pedestal 400 based on the recommended adjustments to lift and move the substrate 108 from the current misaligned position to the desired center position. In one embodiment, if the detection of the misalignment in step 502 and the provision of the gas in step 506 occurred during processing of the substrate 108, the gas may already be flowing in the purge gas region 158 of the chamber volume 123 adjacent to the inlet openings 408 of the plurality of flow conduits 402, so that the opening of the flow valve 412 may be all that is required to flow the gas through the plurality of flow conduits 402. Alternatively, if the detection of misalignment in step 502 and the provision of gas in step 506 occur before processing begins, providing gas flow to the cavity 404 in step 506 may further include initiating gas flow from the purge gas supply 162 to the purge gas region 158 of the chamber volume 123 .

[0059] In step 508, while gas is provided through the plurality of flow conduits 402 based on the recommended adjustment, the position of the substrate 108 in the pocket 404 is continuously monitored by the camera 200 and re-evaluated to determine whether the misalignment has been corrected so that the substrate 108 is centered in the pocket 404. If the substrate remains misaligned with the center of the pocket 404 such that the current gas flow provided through the plurality of flow conduits 402 in step 506 is no longer consistent with the recommended adjustment based on the second misaligned position of the substrate 108, steps 504 and 506 are repeated, wherein a new recommended adjustment is determined based on the second misaligned position of the substrate 108, and the gas flow is modified and provided in 506 based on the new recommended adjustment for the second misaligned position of the substrate 108.

[0060] If it is determined in step 508 that the misalignment of the substrate 108 has been corrected such that the substrate 108 has moved to a new position corresponding to the center position of the recess 404, then in step 510, the processing system 100 stops the flow of gas through the flow conduit 402 to position the substrate 108 in the new position of the recess 404 corresponding to the center position.

[0061] Fig. 6A and 6B is a schematic cross-sectional view of a portion of an example susceptor in a processing chamber 600 according to certain embodiments of the present disclosure.

[0062] The processing chamber 600 includes a susceptor 602 and a preheat ring 604, wherein the susceptor 602 has a recess 603 for receiving a substrate 108 in the recess 603. Heating of the susceptor 602 and the preheat ring 604 facilitates thermal decomposition of a processing gas onto the substrate 108 to form one or more layers on the substrate 108 disposed in the recess 603 of the susceptor 602. The preheat ring 604 can be coupled to a liner assembly 163 of the processing chamber 600 to support and position the preheat ring 604. The preheat ring 604 extends radially inward from the liner assembly 163. As shown in FIG. 6, when the susceptor 602 is in a processing position, the preheat ring 604 is configured to be disposed around the periphery of the susceptor 602.

[0063] The pedestal 602 has a raised border 605 radially outwardly surrounding the recess 603 of the pedestal 602. The raised border 605 has a top surface 607 facing the process gas region 156 of the process chamber 101. The pedestal 602 has an outer flange 614 extending radially outwardly, which is configured to overlap with a corresponding overlapping portion of the preheat ring 604 as described in more detail below. The outer flange 614 extends radially outwardly relative to the raised border 605. A top surface 622 of the outer flange 614 is recessed below the top surface 607 of the raised border 605.

[0064] The preheat ring 604 includes a body 606 (e.g., an annular body) having a top surface 608 that is coplanar with a top surface 610 of the susceptor 602. The body 606 of the preheat ring 604 has an inner flange 612 extending radially inwardly and configured to overlap an outer flange 614 of the susceptor 602. A lower surface 616 of the inner flange 612 is recessed (from below) above a lower surface 618 of the body 606. The inner flange 612 of the preheat ring 604 is disposed above the outer flange 614 of the susceptor 602 to allow the susceptor 602 to be lowered relative to the preheat ring 604 for substrate loading and unloading. Fig. 6A and 6B As shown, the inner flange 612 of the preheat ring 604 and the outer flange 614 of the base 602 are spaced apart from each other (eg, not in contact with each other). Fig. 6A The pedestal 602 is shown raised in a processing position. Figure 6BThe base 602 is shown lowered to a loading position.

[0065] In certain embodiments, the base 602 may further include a plurality of flow conduits 609 extending through the raised border 605. Each of the plurality of flow conduits 609 may include an inlet opening 611 at a side surface 619 of the raised border 605 in fluid communication with an outlet opening 613 at an inner surface 615 of the raised border 605 leading to the pocket 603. In one embodiment, the outlet opening 613 of the flow conduit 609 may be disposed proximate to a top surface 617 of the pocket 603 such that gas flowing through the outlet opening 613 is directed toward a bottom edge 111 of the substrate 108. The plurality of flow conduits 609 described herein can direct a gas flow from the purge gas region 158 to a portion of the substrate 108 positioned in the pocket 603 such that the gas flow from the flow conduits 609 is sufficient to move the substrate 108 within the pocket 603. The gas flow through the plurality of flow conduits 402 may be controlled using a feedback system communicatively coupled to the base 602 and the camera 200. As described above, the camera 200 monitors the position of the substrate 108 in the pocket 603 and provides feedback as to when misalignment of the substrate 108 on the pedestal 106 is detected and corrected.

[0066] When it is desired to move the substrate 108 within the pocket 603 (e.g., to correct for a detected misalignment), the feedback system initiates an automatic correction procedure to move the substrate 108 according to the methods described herein. To move the substrate 108, the pedestal 602 is lowered (e.g., Figure 6B 603) to a predetermined centered position, which enables gas from the purge gas region 158 to flow through the flow conduits 609 toward the substrate 108 in the cavity 603. In one embodiment, when the susceptor 602 is lowered to the predetermined centered position, the susceptor 602 may be lowered about 5 mm relative to the preheat ring 604. When the susceptor 602 is lowered, gas from the purge gas region 158 may flow through the vertical gap 620 between the top surface 622 of the outer flange 614 of the susceptor 602 and the lower surface 616 of the inner flange 612 of the preheat ring 604 and enter the plurality of flow conduits 609. The gas flow through the flow conduits 609 described herein may be able to lift and move the substrate 108 along the top surface 617 of the cavity 603 and enable the substrate 108 to move along the horizontal XY plane of the cavity 603.

[0067] When the feedback system determines that the substrate 108 is centered in the recess 603, the pedestal 602 is raised to the processing position (eg, Fig. 6A6 (shown in the figure), so that the top surfaces of the susceptor 602 and the preheat ring 604 are coplanar. When the susceptor 602 is moved to the processing position, the vertical gap 620 between the top surface 622 of the outer flange 614 of the susceptor 602 is reduced, so that the gas flow from the purge gas region 158 is redirected upward along the side surface 619 of the raised boundary 605 toward the process gas region 156. In the processing position, the vertical gap 620 between the top surface 622 of the outer flange 614 of the susceptor 602 and the lower surface 616 of the inner flange 612 of the preheat ring 604 is about 1 mm or less, such as about 0.5 mm to about 1 mm, such as about 0.6 mm to about 0.8 mm, such as about 0.6 mm.

[0068] Figure 7 6 is a flow chart illustrating an example method 700 for automatically correcting misalignment of a substrate 108 when the substrate 108 is disposed on the example pedestal of FIG6 , according to certain embodiments of the present disclosure. The method 700 begins at 702 by detecting misalignment of the substrate 108 with a center position of a recess 603 of a pedestal 602 in a processing system 100 with the substrate 108 at a first position.

[0069] At 704, upon detecting a misalignment of the substrate 108, the processing system 100 determines a recommended adjustment to correct the detected misalignment and move the substrate 108 to a center position of the well 603. The recommended adjustment may be determined based on a first position of the substrate 108 from which the misalignment was detected by the camera 200.

[0070] At 706, the processing system 100 provides a gas flow to the pedestal 602 based on the recommended adjustments to move the substrate 108 along the horizontal XY plane of the cavity 404. In an embodiment, the gas is provided by lowering the pedestal 602 and the substrate 108 relative to the preheat ring 604 so that the gas flows through a plurality of flow conduits 609 in the pedestal 602 to move the substrate 108 based on the recommended adjustments.

[0071] In step 708, as gas is provided to the pedestal 602 to move the substrate 108, the position of the substrate 108 in the pocket 603 is continuously re-evaluated by the camera 200 to determine whether the misalignment is corrected such that the substrate 108 is moved to a central position of the pocket 603 by the gas flow through the flow conduits 609. If the substrate remains misaligned with the center of the pocket 603 such that the current gas flow through the plurality of flow conduits 609 provided in step 706 is no longer consistent with the recommended adjustment based on the second misaligned position of the substrate 108 detected by the camera 200, steps 704 and 706 are repeated, wherein a new recommended adjustment is determined based on the second misaligned position of the substrate 108, and the gas flow through the plurality of flow conduits 609 is modified and provided in 706 based on the new recommended adjustment for the second misaligned position of the substrate 108.

[0072] If it is determined in step 708 that the misalignment of the substrate 108 has been corrected such that the substrate 108 has moved to a new position corresponding to the center position of the well 603, then in step 710, the gas flow to the pedestal 602 is stopped to allow the substrate 108 to be disposed in the well 603 at the new position corresponding to the center position. In an embodiment, the gas flow to the well 603 of the pedestal 602 may be stopped by raising the pedestal 602. In an embodiment, the pedestal 602 is raised to the processing position and the gas flow to the flow conduit 609 is redirected and stopped accordingly. The stopping of the gas flow in step 710 then allows the substrate 108 to be disposed in its new position in the well 603.

[0073] Fig. 8A and 8B It is shown that some embodiments of the present disclosure can be Figure 2 A schematic top view of an example susceptor 800 for use in the processing system of A.

[0074] exist Fig. 8A In the illustrated embodiment, the pedestal 800 may include a plurality of flow conduits having a plurality of outlet openings 804 disposed in a spiral pattern on a top surface 806 of a recess 803 of the pedestal 800. Each outlet opening 804 and corresponding flow conduit may allow gas to flow from the purge gas region 158 of the chamber volume 123 into the recess 803 of the pedestal 800. In addition to the patterned arrangement of the openings 804, Fig. 8A and 8B The base 800 shown in FIG. Figure 4 The illustrated example base 400 is similarly formed. As such, each outlet opening 804 in the plurality of flow conduits extends through the base 800 to a corresponding inlet opening on the bottom surface of the base 800.

[0075] As shown, the varying outlet openings 804 of each of the plurality of flow conduits in the base 800 are configured to provide varying airflows to different portions of the base 800 and any substrate 108 therein (when disposed on the base 800). In addition to the spiral pattern arrangement of the outlet openings 804 of the plurality of flow conduits, in another embodiment, the diameters of the plurality of outlet openings 804 may also vary, with outlet openings 804 closer to the circumferential edge of the recess 803 having a larger diameter than outlet openings 804 closer to the central region 807 of the recess 803 of the base 800. In the illustrated example, the spiral pattern of outlet openings 804 may thus be formed by an arrangement of a plurality of interlaced lines 808 of outlet openings 804 radiating from the central region 807 of the recess 803 of the base 800. In each radial line 808, the plurality of outlet openings 804 may be formed such that the diameters of the plurality of outlet openings 804 increase from the central region 807 of the recess 803 toward the outer edge of the recess 803.

[0076] When a substrate 108 is positioned on the pedestal 800 in the chamber volume 123 for processing, the substrate 108 may be generally positioned above the central region 807 and centered in the recess 803. However, when the substrate 108 is misaligned in the recess 803, the substrate 108 becomes misaligned relative to the central region 807. When the camera 200 detects such a misalignment, the feedback system may initiate one of the methods described herein to automatically move the substrate 108 and correct the misalignment without user intervention. With respect to the pedestal 800, the automatic correction of the misalignment includes flowing gas through the plurality of flow conduits to lift the substrate 108 and reposition the substrate 108 above the central region 807 of the recess 803.

[0077] Different diameters of the outlet openings 804 of the plurality of flow conduits between the central region 807 and the edge of the well 803 can provide different gas flow rates through some openings 804 compared to other openings 804 when providing gas and using the flow conduits. Changing the diameter of the outlet openings 804 can allow for changing the flow rate of gas to certain portions of the well 803 near the edge of the susceptor 800. In some embodiments, increasing the flow rate of gas through openings 804 near the edge of the well 803 can enable more gas flow to help lift a substrate 108 disposed above such openings 804.

[0078] like Figure 8B As shown, when the substrate 108 is disposed on the pedestal 800 and is misaligned relative to the central region 807, the spiral pattern design and increased diameter of the plurality of outlet openings 804 near the outer edge of the recess 803 allow more gas to flow to the specific misaligned portion of the substrate 108. Figure 8B As shown, when compared to portions of the substrate 108 over the central region 807 and / or portions that are closer to the central region 807 than the misaligned portions, portions of the substrate 108 that are misaligned relative to the central region 807 will tend to be disposed over more and larger outlet openings 804 in the susceptor 800 in response to being opposed to the corresponding misaligned portions. The greater the misalignment of the substrate 108, the more the substrate 108 can be disposed over a greater number of outlet openings 804.

[0079] Because the misaligned portion of the substrate 108 is disposed over more flow conduits 802 and larger outlet openings 804 , the pedestal 800 allows the feedback system to provide more airflow to specifically lift and move the misaligned portion of the substrate 108 .

[0080] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope of the same is determined by the claims that follow.

Claims

1. A processing system for automatically centering a substrate in a processing chamber, comprising: a processing chamber comprising a substrate support disposed within a chamber volume of the processing chamber, the substrate support comprising a recess for receiving a substrate; a plurality of flow conduits extending between a top surface of the recess of the substrate support and a bottom surface of the substrate support; and An imaging device is coupled to the processing chamber and is configured to monitor a position of the substrate in the pocket of the substrate support. 2 . The processing system of claim 1 , wherein each of the plurality of flow conduits further comprises a flow valve for controlling gas flow through the plurality of flow conduits.

3. The processing system of claim 1, wherein the imaging device is configured to detect misalignment of the substrate relative to a center position of the recess of the substrate support. 4 . The processing system of claim 1 , wherein each of the plurality of flow conduits is configured to direct a gas flow from the chamber volume to the top surface of the pocket.

5. The processing system of claim 1, wherein each of the plurality of flow conduits comprises an outlet opening formed in the top surface of the recess, wherein the outlet openings of the plurality of flow conduits are formed between a central region of the recess and a circumferential edge of the recess.

6. The processing system of claim 5, wherein each of the outlet openings of the plurality of flow conduits comprises a diameter, and wherein the diameter of the outlet openings closer to the central region of the pocket is smaller than the diameter of the outlet openings farther from the central region.

7. The processing system of claim 5, wherein the outlet openings of the plurality of flow conduits are arranged in a spiral pattern on the top surface of the pocket.

8. The processing system of claim 1 , further comprising a controller communicatively coupled to the imaging device and the substrate support, wherein the controller is configured to provide gas flow through at least some of the plurality of flow conduits in response to the imaging device detecting misalignment of the substrate in the recess of the substrate support.

9. The processing system of claim 1 , further comprising a CPU communicatively coupled to the imaging device and configured to provide instructions for a recommended adjustment in response to a misalignment of the substrate detected by the imaging device, wherein the recommended adjustment corrects the misalignment of the substrate detected by the imaging device.

10. The processing system of claim 9, further comprising a controller communicatively coupled to the imaging device and the substrate support, wherein the controller is configured to provide gas flow through at least some of the plurality of flow conduits to move the substrate based on the instructions for the recommended adjustments.

11. A processing system for automatically centering a substrate in a processing chamber, comprising: a processing chamber comprising a susceptor and a preheat ring disposed within a chamber volume of the processing chamber, wherein the susceptor comprises a recess for receiving a substrate, and wherein the preheat ring radially overlaps the susceptor; a plurality of flow conduits extending through portions of the base; and An imaging device is coupled to the processing chamber and is configured to monitor a substrate in the cavity of the susceptor.

12. The processing system of claim 11, wherein the radially overlapping portion of the preheat ring is disposed above the radially overlapping portion of the susceptor.

13. The processing system of claim 11, wherein each of the plurality of flow conduits is configured to flow gas from the chamber volume into the pocket of the pedestal when the pedestal is lowered relative to the preheat ring.

14. The processing system of claim 11, further comprising a controller communicatively coupled to the imaging device and the pedestal, wherein the controller is configured to lower the pedestal relative to the preheat ring in response to the imaging device detecting a misalignment of the substrate in the recess of the pedestal.

15. The processing system of claim 11 , further comprising a CPU communicatively coupled to the imaging device, wherein the CPU is configured to provide instructions for a recommended adjustment in response to a misalignment of the substrate detected by the imaging device, wherein the recommended adjustment corrects the misalignment of the substrate detected by the imaging device.

16. A method for automatically centering a substrate in a processing chamber, the method comprising: detecting misalignment of a substrate loaded on a substrate support disposed in a chamber volume of a processing chamber; determining a recommended adjustment for the substrate to correct the detected misalignment; providing a flow of gas from the chamber volume to the substrate support according to the recommended adjustment; detecting a corrected position of the substrate on the substrate support, wherein the corrected position corresponds to a center position of the substrate support; and The gas flow to the substrate support is stopped to position the substrate on the substrate support in the correct position.

17. The method according to claim 16, further comprising: The position of the substrate on the substrate support is continuously monitored after providing a gas flow to the substrate support to detect a change in the position of the substrate relative to the substrate support.

18. The method of claim 16, wherein determining a recommended adjustment to correct the misalignment of the substrate comprises: A recommended adjustment is determined to move the substrate to the center position of the substrate support.

19. The method of claim 16, wherein providing a gas flow to the substrate support comprises: Gas is flowed through a plurality of flow conduits disposed in the substrate support, wherein the plurality of flow conduits direct gas from a purge gas region of the chamber volume below the substrate support through the substrate support to a top surface of the substrate support.

20. The method of claim 16, wherein the substrate support comprises a pedestal and a preheat ring radially overlapping the pedestal, and wherein providing a gas flow to the substrate support comprises: The susceptor is lowered relative to the preheat ring to allow gas to flow from the chamber volume through a plurality of flow conduits extending through the susceptor to a top surface of the susceptor.

Images