Automated substrate placement to chamber center

Abstract

The embodiments disclosed herein include a method for centering a substrate in a chamber. In one embodiment, the method includes the steps of: inserting the substrate into the chamber by a robotic arm; obtaining an incremental time value of a second pyrometer relative to a first pyrometer, wherein the incremental time value is the duration between when the first pyrometer is covered by the substrate and when the second pyrometer is covered by the substrate; calculating a time offset of the incremental time value relative to an ideal incremental time value, wherein the ideal incremental time value is the incremental time value when the substrate is perfectly centered in a first direction perpendicular to the movement of the substrate; and comparing the time offset value with a graph or lookup table that correlates the time offset value with a distance offset value.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the field of semiconductor processing, and more specifically to a method for centering a substrate within a cavity using a pyrometer. Prior Technology

[0002] In semiconductor manufacturing, proper centering of the substrate within the chamber is crucial for achieving highly uniform processing results. For example, in a heat treatment chamber, the substrate is ideally located at the center below an array of lamps. The lamps can be controlled in zones (e.g., central, intermediate, and outer regions). Properly centering the substrate allows for appropriate orientation of areas on the substrate to provide the desired heating for each area.

[0003] A robotic arm (e.g., an end effector) inserts a substrate into a cavity. The robotic arm is controlled by a processor. The processor provides instructions for moving the robotic arm within the cavity. For example, the robotic arm may include the ability to move the substrate in the X and Y directions. As used herein, the X direction may be perpendicular to the direction of movement when the substrate is inserted into the cavity, and the Y direction may be parallel to the direction of movement when the substrate is inserted into the cavity.

[0004] The processor can include instructions for correctly placing the substrate. However, in some cases, the centering position may drift during use and / or after tooling maintenance (e.g., scheduled maintenance (PM)). Therefore, it may be necessary to recalibrate the robot to properly center the substrate. Typically, this calibration is done manually. That is, trained engineers or similar personnel can be responsible for improving substrate centering. This involves opening the chamber and visually inspecting the center position of the substrate. Opening the chamber is a time-consuming process because the chamber may need to be re-identified and / or re-dried after opening. Furthermore, human error can occur during centering. Therefore, existing centering techniques are not ideal for many semiconductor manufacturing processes. Summary of the Invention

[0005] The embodiments disclosed herein include a method for centering a substrate in a chamber. In one embodiment, the method includes the steps of: inserting the substrate into the chamber by a robotic arm; obtaining an incremental time value of a second pyrometer relative to a first pyrometer, wherein the incremental time value is the duration between when the first pyrometer is covered by the substrate and when the second pyrometer is covered by the substrate; calculating a time offset value of the incremental time value relative to an ideal incremental time value, wherein the ideal incremental time value is the incremental time value when the substrate is perfectly centered in a first direction perpendicular to the movement of the substrate; comparing the time offset value with a graph or lookup table that correlates the time offset value with a distance offset value, wherein the distance offset value is how far the substrate is from being completely centered in the first direction; retracting the substrate; moving the robotic arm along the first direction by the distance offset value; and inserting the substrate into the chamber by the robotic arm.

[0006] The embodiment may also include a method for centering a substrate in a chamber, comprising the steps of: inserting the substrate into the chamber by a robotic arm, wherein the chamber includes a first pyrometer located below the substrate and a plurality of second pyrometers; determining incremental time values ​​of the plurality of second pyrometers relative to the first pyrometer; calculating a time offset value of the incremental time value relative to an ideal incremental time value, wherein the ideal incremental time value is the incremental time value when the substrate is perfectly centered in a first direction perpendicular to the movement of the substrate; and finding the best match in a graph or lookup table that correlates the time offset value with a distance offset value, wherein the distance offset value is how far the substrate is from the off-center when perfectly centered in the first direction.

[0007] The embodiments may also include a semiconductor processing tool. In an embodiment, the semiconductor processing tool includes: a chamber; a plurality of pyrometers arranged along a bottom or top surface of the chamber; a plurality of lamps opposite to the plurality of pyrometers; a robotic arm for inserting a substrate into the chamber, wherein the robotic arm is displaceable in a first direction and a second direction, the second direction being perpendicular to the first direction; and a processor, wherein the processor includes instructions for centering the substrate in the chamber using readings from the plurality of pyrometers, wherein centering the substrate in the chamber is performed without opening the chamber. Simple Explanation of the Diagram

[0008] Figure 1A is a cross-sectional view of a semiconductor processing tool with a robotic arm that inserts a substrate, according to an embodiment.

[0009] Figure 1B is a plan view of the semiconductor processing tool in Figure 1A according to an embodiment.

[0010] Figure 1C is a plan view illustrating the XY robot plane defined by the range of the robot processor and the XY chamber plane parallel to the XY robot plane according to an embodiment.

[0011] Figure 2A is an illustration depicting the insertion of a substrate into a cavity according to an embodiment, wherein the substrate is perfectly aligned in the X direction.

[0012] Figure 2B is a graph illustrating the normalized pyrometer signal during the insertion of the substrate into the chamber according to an embodiment.

[0013] Figure 3A is an illustration depicting a fully centered substrate and a substrate offset in the X direction according to an embodiment.

[0014] Figure 3B is a graph showing the time offset values ​​and corresponding X-direction offsets according to an embodiment.

[0015] Figure 3C is a process flowchart depicting the process of determining the offset of the substrate in the X direction according to an embodiment.

[0016] Figure 4A is an illustration depicting a substrate inserted into a chamber in a manner that provides proper centering in the Y direction, according to an embodiment.

[0017] Figure 4B is a process flowchart depicting the process of determining the offset of the substrate in the Y direction according to an embodiment.

[0018] Figure 5 is a block diagram illustration of an exemplary computer system according to an embodiment of the present disclosure. Implementation

[0019] This document describes a method for centering a substrate within a cavity using a pyrometer. In the following description, numerous specific details are set forth to provide a thorough understanding of the embodiments. It will be apparent to those skilled in the art that practice of the embodiments does not require these specific details. In other instances, well-known forms have not been described exhaustively to avoid unnecessarily obscuring the embodiments. Furthermore, it should be understood that the various embodiments shown in the accompanying drawings are illustrative representations and are not necessarily drawn to scale.

[0020] As described above, current processes for centering a substrate within a cavity involve manual intervention and opening the cavity. Therefore, this process is prone to human error, and the cavity requires considerable downtime. Therefore, the embodiments disclosed herein include a substrate centering process that can be implemented by a processor without opening the cavity. Specifically, the embodiments utilize a pyrometer present in the cavity to detect the presence of the substrate. The position of the pyrometer relative to the center of the cavity is known. Thus, the edges of the substrate can be detected at multiple locations and multiple times. This allows for the calculation of the substrate's offset relative to the center of the cavity. The embodiments disclosed herein allow centering in both the X and Y directions.

[0021] In one embodiment, edge detection is possible due to the chamber's structure. A plurality of lamps can be positioned opposite the pyrometer. For example, the lamps can be used to heat the substrate for heat treatment operations, such as thermal oxidation. In one embodiment, the lamps are kept on between treatments of different substrates to maintain their warmth. Therefore, when no substrate is present, the pyrometer detects a relatively strong signal. When the next substrate is inserted into the chamber, the substrate blocks the thermal signal from the lamps. Therefore, the signal from the pyrometer weakens. This signal reduction can be used as an indication of the presence of a substrate edge. By monitoring the timing of edge detection by the various pyrometers, substrate offset can be determined.

[0022] Referring now to FIG1A, a cross-sectional view of a semiconductor processing tool 100 according to an embodiment is illustrated. In the embodiment, the semiconductor processing tool 100 may be a thermal processing tool, such as a rapid thermal processing (RTP) tool, etc. The semiconductor processing tool 100 may be used to perform processing operations, such as thermal oxidation, annealing, etc. In one embodiment, the semiconductor processing tool 100 may include a bottom 105 and a cover 112. The bottom 105 and the cover 112 may be part of a housing forming an internal space in which processing is performed.

[0023] In one embodiment, a plurality of lamps 113 may be disposed above the cover 112. The cover 112 may be substantially transparent to infrared radiation. Thus, the lamps 113 can provide heat energy to the internal space of the semiconductor processing tool 100 for processing a substrate, such as substrate 101. The lamps 113 may be controlled in a plurality of regions. For example, the lamps 113 may include an inner region, a middle region, and an outer region. However, it should be understood that embodiments may include any number of lamp regions (e.g., one or more regions).

[0024] In one embodiment, a plurality of pyrometers 120 may be disposed via the bottom 105 of the semiconductor processing tool 100. In the illustrated embodiment, for ease of illustration, all pyrometers 120A to 120D are shown in a single plane. However, it should be understood that the pyrometers 120 may be located in different planes from each other, as shown in the plan view of FIG1B. As shown, the pyrometers 120 receive signals (e.g., thermal signals) from the lamp 113, as indicated by the arrows. However, the signal from the first pyrometer 120A is blocked by the substrate 101. Although illustrated as being covered by the substrate 101, the signal to the second pyrometer 120B passes through the substrate 101. In fact, the second pyrometer 120B is not covered by the substrate 101, as shown in FIG1B.

[0025] In one embodiment, substrate 101 may be inserted into semiconductor processing tool 100. For example, robotic arm 110 (e.g., end effector) may hold substrate 101 and transfer substrate 101 into semiconductor processing tool 100. Robotic arm 110 may place substrate 101 within edge ring 107. Robotic arm 110 may include the ability to move substrate 101 in both the X direction (entering and exiting the plane of FIG. 1A) and the Y direction (from left to right in FIG. 1A). In embodiments, substrate 101 may be any substrate suitable for semiconductor processing operations. In a particular embodiment, substrate 101 may be a silicon wafer having any shape factor (e.g., 300 mm, 450 mm, etc.). However, other semiconductor substrates 101 or substrates of any other material may also be used.

[0026] Referring now to FIG. 1B, a plan view of a semiconductor processing tool 100 according to an embodiment is illustrated. In the illustrated embodiment, the cover 112 and lamp 113 are omitted so that the substrate 101 and pyrometer 120 can be clearly seen. As shown, the substrate 101 is inserted by a robotic arm 110. As the substrate 101 is inserted into the semiconductor processing tool 100, the pyrometer 120 is covered. For example, at the time point shown in FIG. 1B, the first pyrometer 120A is covered by the substrate 101, while the remaining pyrometers 120B, 120C, and 120D are exposed. As the substrate 101 continues to enter the semiconductor processing tool, the remaining portions of the pyrometers 120 will be covered. When each pyrometer is covered, a signal indicating edge detection is provided, as will be described in more detail below. By combining the edge detection signal with the time when the edge is detected, the centering of the substrate 101 can be determined. A more detailed process for calculating the centering is provided below.

[0027] In the illustrated embodiment, a set of four pyrometers 120A to 120D is shown. However, it should be understood that the embodiment can utilize as few as two pyrometers to perform the centering operation. Alternatively, more than four pyrometers 120 can be used. Increasing the number of pyrometers allows for more precise centering of the substrate 101. For example, the center of the substrate can be set to an error as low as approximately 0.25 mm or less. Since the existing process is manual, such errors are considered acceptable because they are generally more accurate than currently provided human error.

[0028] Referring now to FIG1C, a plan view (in the XY dimensions) depicting the robot processor and chamber according to one embodiment is illustrated. Specifically, the robot has a plane 196 defined by the X robot and the Y robot, and the chamber has a plane 197 defined by the X chamber and the Y chamber. A mechanical blade 198 is movable within the robot plane 196, which partially overlaps with the chamber plane 197. Thus, the mechanical blade 198 can be inserted into the chamber 197.

[0029] It should be understood that placement is accomplished by the mechanical blade 198 by reaching waypoints on the X-robot and Y-robot planes, which are defined by the range of the robot processor center and parallel to the X-chamber and Y-chamber planes. The waypoints of the chambers are taught to match the center of the chamber. This is accomplished by finding the robot plane values ​​X-robot and Y-robot (e.g., (A, B)) representing the point (0,0) on the chamber plane 197. More generally, the process involves matching the robot's coordinate system (X-robot, Y-robot) with the chamber coordinate system (X-chamber, Y-chamber). This process is commonly referred to as "robot teaching".

[0030] Referring now to Figure 2A, an illustration shows the edge detection over time according to an embodiment. In the embodiment shown in Figure 2A, substrate 201 is illustrated as perfectly centered on the X-axis (upper and lower). This is considered ideal and is used to illustrate the edge detection process. As shown in Figure 2A, a series of substrate edges 2011 to 2015 are illustrated as substrate 2011 moves through the semiconductor processing tool. Each detected edge 2011 to 2014 corresponds to a position of pyrometers 220A to 220D. Edge 2015 is the ideal ending position, where the substrate center is located at the cavity center L0 (i.e., (0,0)). A more detailed description of how Y-axis centering is implemented is provided below.

[0031] In the ideal case shown in Figure 2A, the center point (L1 to L4) of the substrate 201 at each location is set at X=0. Since the position (X, Y) of the pyrometer 220 is known, and the radius of the substrate is known, trigonometry can be used to calculate the position in the Y direction. For example, for the fourth pyrometer 220D, the XY position is X=140 and Y=0. When the substrate radius is 150 mm, the center L4 of the substrate 201 at time 201 is provided by Equation 1:

[0032] Y(L4) = Y(220D) - (R² - X(220D)²)¹ / ² = -53.8 Equation 1

[0033] Similar equations can be constructed using trigonometry to find the Y value of other center points.

[0034] In this embodiment, substrate 201 moves at a constant speed past pyrometers 220A to 220D. The substrate can then decelerate to reach the endpoint position at time 2015. Therefore, the time difference between positions L1 to L4 is proportional to the distance shown in the figure. As will be described in more detail below, the time values ​​at different positions 220A to 220D can be used to determine the offset in the X direction.

[0035] Referring now to Figure 2B, a graph illustrating signals 2211 to 2214 detected by each pyrometer versus time is shown. The graph in Figure 2B is a normalized graph, with a maximum value of 1 and a minimum value of 0. As shown, each signal 2211 to 2214 drops sharply at the point where the substrate covers the pyrometer. This is because the substrate blocks thermal radiation from the lamps above, which maintain a constant power. As shown in Figure 2B, the time when the pyrometer is covered is considered to be the point where signal 221 passes through the 0.5 mark of signal strength. As shown, the slope of signals 2211 to 2214 may not be uniform. For example, signal 2214 has a smaller slope than signal 2211. This may be due to the position of the pyrometer. That is, a pyrometer with an X-coordinate closer to 0 may have a relatively steeper slope than a pyrometer with an X-coordinate farther from 0.

[0036] In the illustrated embodiment, each pyrometer is covered at different times (e.g., t(L1), t(L2), t(L3), and t(L4)). To correlate each time, one of the pyrometers is used as a reference point. For example, an incremental time value (Δt) relative to a first time t(L1) is provided. In other words, Equation 2 can be used to calculate the value of Δt.

[0037] Δt(L2) = t(L2) - t(L1) = 0.05 Equation 2

[0038] Similar equations can be provided to find the Δt value for other pyrometers.

[0039] Referring now to FIG3A, an illustration is shown of a perfectly centered substrate 301A and a substrate 301B with an offset distance dx according to an embodiment. FIG3A is illustrated to explain how to calculate the time offset value (dΔt(Ln)) for various X offsets. For example, in FIG3A, the dx distance is 30 mm. First, the center point y(L2) of the ideal substrate 301A is calculated. Equation 1 can be used to calculate the center point y(L2). Then, Equation 3 is used to calculate the center point y'(L2) of the offset substrate 301B.

[0040]

[0041] y'(L2)=y(320B)-(R 2-(x(320B)-dx) 2) 1 / 2 Equation 3

[0042] Similar equations can be provided for other L values ​​(L1, L3, and L4).

[0043] Then, Equation 4 is used to calculate the value of Δy (dy(Ln)).

[0044] dy(Ln)=y'(Ln)-y(Ln) Equation 4

[0045] Since distance is proportional to time, the time associated with each increment y can be provided by Equation 5.

[0046] dt(Ln)=dy(Ln) / v Equation 5

[0047] In Equation 5, v is the speed of the robotic arm. Ultimately, the time offset dΔt(Ln) can be provided by subtracting dt(L1) from the time associated with each other increment y value. The time offset dΔt(Ln) can be determined for all values ​​of offset dx by changing the value of offset dx. This equivalent value can be stored as a graph or lookup table. In an alternative embodiment, the time offset dΔt(Ln) can be determined by experimentation and / or machine learning.

[0048] Referring now to Figure 3B, a graph illustrating the plotting of illustrated time offsets dΔt(L2), dΔt(L3), and dΔt(L4) and their corresponding dx values ​​according to an embodiment is shown. Circles represent time offset values ​​calculated for the offset substrate. The time offset values ​​are fitted onto the line to provide the most accurate dx value. For example, in Figure 3B, the time offset value corresponds to approximately 1.4 mm of dx. Therefore, the robotic arm needs to be offset by 1.4 mm to correct the centering of the substrate. Although illustrated graphically, it should be understood that a lookup table or similar method can also be used to determine the offset dx. Furthermore, it should be understood that fewer or more than three time offset values ​​can be used to determine the dx value. For example, a single dΔt(L2) value can be determined using a set of two pyrometers, which can then be used to determine dx.

[0049] Referring now to Figure 3C, a process flowchart according to an embodiment is illustrated, showing process 380 for determining the offset of the substrate in a direction perpendicular to the robot's movement. In the described process 380, a set of two pyrometers is used. However, it should be understood that in some embodiments, more than two pyrometers may be used.

[0050] In one embodiment, process 380 begins with operation 381, which includes inserting a substrate into a chamber using a robotic arm. The chamber can be any suitable chamber with heating lamps and two or more pyrometers. For example, a semiconductor processing tool similar to the semiconductor processing tool 100 described in more detail above can be used. In this embodiment, the robotic arm can insert the substrate into the chamber along a linear direction. In the context of the embodiments described herein, the linear direction can be the Y-axis as described above. In one embodiment, the robotic arm may not be correctly aligned with the center of the chamber. In other words, the robotic arm may have an offset in the X-direction (i.e., perpendicular to the direction of displacement of the robotic arm).

[0051] In an embodiment, process 380 may continue to operation 382, ​​which includes obtaining an incremental time value of the second pyrometer relative to the first pyrometer. The incremental time value may be the time between detecting the edge of the substrate with the first pyrometer and detecting the edge of the substrate with the second pyrometer. Edge detection of the substrate can be determined by observing the pyrometer signal. For example, the signal may drop significantly as the substrate passes through the pyrometer, similar to the illustration in Figure 2B. In a particular embodiment, edge detection may use the normalized midpoint of the pyrometer signal as the time when the pyrometer is considered to be covered.

[0052] In one embodiment, process 380 may continue to operation 383, which includes calculating the time offset of the incremental time value relative to an ideal incremental time value. In another embodiment, the ideal incremental time value may be the incremental time value between the first and second pyrometers when the substrates are perfectly aligned. The ideal incremental time value may be a measurement value stored in memory, or it may be a calculated value stored in memory.

[0053] In an embodiment, process 380 may continue to operation 384, which includes comparing the time offset value with a graph or lookup table that associates the time offset value with a distance offset value. In an embodiment, when a graph is used, the graph may resemble the one shown in FIG3B. As described above, the graph or lookup table can be generated analytically and stored in memory. In other embodiments, the graph or lookup table can be determined experimentally using machine learning algorithms or the like. In an embodiment, the distance offset value is the distance by which the substrate deviates from the true center in a direction perpendicular to the substrate's direction of travel (i.e., in the X direction using the coordinate system described herein).

[0054] In one embodiment, process 380 may continue to operation 385, which includes retracting the substrate from the chamber. In one embodiment, the substrate may be retracted along the same path used to insert the substrate into the chamber.

[0055] In one embodiment, process 380 may continue to operation 386, which includes moving the robotic arm by a distance offset value in a direction perpendicular to the direction of travel of the substrate into and out of the chamber. Ideally, the distance offset value can correct for misalignment of the substrate.

[0056] In an embodiment, process 380 may continue to operation 387, which includes inserting the substrate into the chamber using a robotic arm. Ideally, the alignment is now corrected. However, it should be understood that the alignment can be rechecked by repeating process 380 any number of times. In a particular embodiment, process 380 may be repeated until the measured offset is within a given specification. For example, the specification may be within 5 mm of the true center, within 2 mm of the true center, or within 0.25 mm of the true center.

[0057] It should be understood that process 380 can be executed without human intervention. That is, a processor capable of accessing pyrometer signals, values ​​stored in memory, etc., can automatically implement process 380. Process 380 can be executed after a preset number of substrates have been processed, after planned maintenance, after any other desired duration, or after other predetermined events.

[0058] Referring now to FIG4A, an illustration shows a method for centering a substrate in the direction of motion (i.e., the Y direction in FIG4A) according to one embodiment. In one embodiment, centering in the direction of motion is complex because the speed of the substrate is not constant. That is, after passing the pyrometer, the robotic arm must decelerate to stop at the correct center point in the Y direction. In one embodiment, Y-direction centering can be performed after X-direction centering is completed.

[0059] When the substrate is correctly aligned in the X direction, the position of the center point L1 of the substrate 4011 when it covers the first pyrometer 420A is known. Therefore, if a deceleration process is used to stop the substrate on the first pyrometer 420A, a simple offset (equal to the distance between L1 and L0 (i.e., (0,0))) can be applied to the robot so that when the substrate is at point 401E, the substrate has a center point falling on L0. When the normalized pyrometer signal is approximately 0.5, the first pyrometer 420A can be considered covered. If the signal strength is higher or lower than 0.5 (or exceeds a threshold of approximately 0.5), the deceleration process is adjusted and rechecked until the signal strength is 0.5 or within the predetermined threshold. In the described embodiment, a single pyrometer reading 420A is sufficient to center the substrate in the Y direction. Of course, the center point can be further confirmed by using an additional pyrometer (e.g., a second pyrometer 420B at position 4012).

[0060] Referring now to FIG4B, a process flow diagram illustrating a process 490 for centering a substrate in the direction of motion (i.e., the Y direction as described herein) according to one embodiment is shown.

[0061] In one embodiment, process 490 begins with operation 491, which includes inserting the substrate into the chamber a first distance using a robotic arm, such that the substrate stops at the first pyrometer. Operation 491 can begin after the substrate has been correctly aligned in the orthogonal direction (i.e., the X direction as described herein). Once the center in the X direction is known, the distance to the first pyrometer should be known. This known distance can be used as the starting point for the first distance. In one embodiment, the first distance can be traveled at a constant speed until it approaches the end of the first distance. At this point, a deceleration process can be implemented to bring the substrate to a stop at the first pyrometer.

[0062] In an embodiment, process 490 can proceed to operation 492, which includes determining whether the substrate has correctly stopped at the first pyrometer. In an embodiment, if the normalized pyrometer signal is 0.5 or within a predetermined range of 0.5, the substrate is considered to have stopped correctly. If the substrate does not stop at the desired position, operations 491 and 492 are repeated by changing the first distance and / or deceleration processing until the correct position is obtained. If the pyrometer signal is greater than 0.5, a positive offset is provided; if the pyrometer signal is less than 0.5, a negative offset is provided. The required amount of movement can be given by the slope of the pyrometer signal and the pyrometer signal value. That is, the time axis in Figure 2B is converted to a Y value using the equation Y=v*t, where v is velocity and t is time.

[0063] In an embodiment, process 490 may continue to operation 493, which includes adding a centering offset to a first distance when the substrate correctly stops at the first pyrometer. In an embodiment, the centering offset may be equal to the Y value of the center point of the substrate when the first pyrometer was initially covered. Therefore, the addition of the Y value results in endpoint 401E being correctly centered at the (0,0) coordinate (i.e., the center of the chamber).

[0064] In one embodiment, process 490 may continue to operation 494, which includes retrieving the substrate from the chamber. In one embodiment, the retrieving of the substrate may be the reverse of the speed, acceleration, distance, etc., used to insert the substrate into the chamber.

[0065] In an embodiment, process 490 can continue into operation 495, which includes inserting the substrate into the chamber a second distance equal to the sum of the first distance and the centering offset. Additionally, acceleration and deceleration processes used to find the centering offset can also be used during substrate insertion. Therefore, the center point of the substrate should be located on L0 (i.e., (0,0)) or within a desired threshold of (0,0). More specifically, the acceleration, deceleration, and constant velocity of the substrate are the same between the operation for finding the centering offset and the insertion included in operation 495. What changes is the duration of the constant velocity. The duration of the constant velocity can be determined using the centering offset (e.g., dividing the centering offset distance by the constant velocity to determine the additional duration for which the constant velocity is applied to land on (0,0).

[0066] Figure 5 illustrates a schematic representation of a machine in an exemplary form of computer system 500, within which a set of instructions can be executed to cause the machine to perform any one or more of the methods described herein. In alternative embodiments, the machine may be connected (e.g., networked) to other machines in a local area network (LAN), intranet, extranet, or internet. The machine may operate within a server or client machine in a client-to-server network environment, or may act as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), tablet computer, set-top box (STB), personal digital assistant (PDA), cellular phone, web browser, server, network router, switch, or bridge, or any machine capable of executing a set of instructions specifying the actions to be taken (sequentially or otherwise) by this machine. Furthermore, although only a single machine is illustrated, the term "machine" should also be considered as a collection of any machine (e.g., a computer) that individually or jointly executes a set (or more) of instructions to perform any one or more of the methods described herein.

[0067] An exemplary computer system 500 includes a system processor 502, main memory 504 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM), such as synchronous DRAM (SDRAM) or Rambus DRAM (RDRAM), etc.), static memory 506 (e.g., flash memory, static random access memory (SRAM), etc.), and auxiliary memory 518 (e.g., data storage device) communicating with each other via a bus 530.

[0068] Processor 502 represents one or more general-purpose processing devices, such as microprocessors, central processing units, etc. More specifically, processor 502 may be a Complex Instruction Set Computing (CISC) microprocessor, a Reduced Instruction Set Computing (RISC) microprocessor, a Very Long Instruction Word (VLIW) microprocessor, a processor implementing other instruction sets, or a processor implementing a combination of instruction sets. Processor 502 may also be one or more special-purpose processing devices, such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal system processors (DSPs), network system processors, etc. Processor 502 is configured to execute processing logic 526 to perform the operations described herein.

[0069] The computer system 500 may further include a network interface device 508. The computer system 500 may also include a video display unit 510 (e.g., a liquid crystal display (LCD), a light-emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 512 (e.g., a keyboard), a cursor control device 514 (e.g., a mouse), and a signal generation device 516 (e.g., a speaker).

[0070] Auxiliary memory 518 may include machine-accessible storage medium 532 (or more specifically, computer-readable storage medium) storing one or more sets of instructions (e.g., software 522) embodying any one or more methods or functions described herein. Software 522 may also reside wholly or at least partially within main memory 504 and / or processor 502 during execution by computer system 500, which also constitute machine-readable storage media. Software 522 may also be sent or received on network 520 via network interface device 508.

[0071] Although machine-readable media 532 is shown as a single medium in the exemplary embodiments, the term "machine-readable storage medium" should be considered as including a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more sets of instructions. The term "machine-readable storage medium" should also be considered as including any medium capable of storing, encoding, or carrying sets of instructions to be executed by a machine and to enable the machine to perform any or more of the methods disclosed herein. Therefore, the term "machine-readable storage medium" should be considered as including, but not limited to, solid-state memory, as well as optical and magnetic media.

[0072] According to an embodiment of this disclosure, a machine-accessible storage medium has instructions stored thereon that cause a data processing system to execute a method for centering a substrate in a chamber using pyrometers. The method includes measuring an incremental time value between the covers of a first pyrometer and the covers of a second pyrometer. The method includes calculating a time offset value relative to an ideal incremental time value. The method includes comparing the time offset value with a graph or lookup table that correlates the time offset value with a distance offset value. The method includes retrieving the substrate, adjusting the robotic arm based on the distance offset value, and reinserting the substrate into the chamber.

[0073] Therefore, a method for centering the substrate using pyrometer data was revealed.

[0074] 100: Semiconductor processing tools 101:Substrate 105: Bottom 107: Edge ring 110: Robotic Arm 112: Cover 113: Lamp 196: Plane 197: Plane 198: Mechanical blades 201:Substrate 380: Processing 490: Processing 500: Computer System 502: System Processor 504: Main Memory 506: Static Memory 508: Network Interface Device 510: Video display unit 512: Alphanumeric Input Device 514: Vernier control device 516: Signal generating device 518: Auxiliary Memory 522: Software 526: Processing Logic 530: Busbar 532: Machine-accessible storage media 120A to 120D: High Temperature Gauge 2011 to 2015: Substrate edge 220A to 220D: High Temperature Gauge 221 1 to 221 4: Signals 301A to 301B: Substrate 381 to 387: Operations 401 1 to 401 2: Substrate 420A to 420B: High Temperature Gauge 491 to 495: Operations

[0075] Domestic storage information (please note the order of storage institution, date, and number) none Overseas deposit information (please note the order of deposit country, institution, date, and number) none

Claims

1. A method for centering a substrate in a chamber, comprising the steps of: inserting the substrate into the chamber by a robotic arm; obtaining an incremental time value of a second pyrometer relative to a first pyrometer, wherein the incremental time value is a duration between when the first pyrometer is covered by the substrate and when the second pyrometer is covered by the substrate; calculating a time offset of the incremental time value relative to an ideal incremental time value, wherein the ideal incremental time value is the incremental time value when the substrate is perfectly centered in a first direction perpendicular to the movement of the substrate; comparing the time offset value with a graph or a lookup table relating the time offset value to a distance offset value, wherein the distance offset value is how far the substrate is from being perfectly centered in the first direction; retracting the substrate; moving the robotic arm along the first direction by the distance offset value; and inserting the substrate into the chamber by the robotic arm.

2. The method as described in claim 1, wherein the robotic arm has a constant speed in the first direction when the substrate passes the first pyrometer and the second pyrometer.

3. The method as described in claim 1, wherein the graph or lookup table is obtained through experimentation and machine learning, or is calculated through analysis.

4. The method as claimed in claim 1, wherein the first pyrometer has a first standardized pyrometer signal between 0 and 1 and the second pyrometer has a second standardized pyrometer signal between 0 and 1, and wherein the first pyrometer and the second pyrometer are considered to be covered when the standardized signal passes through 0.

5.

5. The method as described in claim 4, wherein a slope of the first standardized pyrometer signal is different from a slope of the second standardized pyrometer signal.

6. The method as described in claim 1, further comprising the step of: repeating the method one or more times.

7. The method as described in claim 6, wherein the method is stopped when the distance offset value is 0.25 mm or less.

8. The method as described in claim 1, further comprising the steps of: a third pyrometer and a fourth pyrometer.

9. The method of claim 8, further comprising the steps of: obtaining a second incremental time value of the third pyrometer relative to the first pyrometer, wherein the second incremental time value is a duration between when the first pyrometer is covered by the substrate and when the third pyrometer is covered by the substrate; obtaining a third incremental time value of the fourth pyrometer relative to the first pyrometer, wherein the third incremental time value is a duration between when the first pyrometer is covered by the substrate and when the fourth pyrometer is covered by the substrate; calculating a time offset of the second incremental time value and the third incremental time value relative to ideal incremental time values, wherein the ideal incremental time values ​​are the incremental time values ​​when the substrate is perfectly centered in the first direction; and comparing the time offset values ​​with a graph or lookup table that associates the time offset values ​​with a distance offset value, wherein the distance offset value is how far the substrate is from being completely centered in the first direction.

10. The method as claimed in claim 1, further comprising the steps of: after centering the substrate in the first direction, centering the substrate in a second direction parallel to the movement of the substrate.

11. The method as described in claim 10, wherein centering the substrate in the second direction includes the following steps: The robotic arm inserts the substrate into the chamber by a first distance, causing the substrate to stop at the first pyrometer; it determines whether the substrate stops correctly at the first pyrometer; when the substrate stops correctly at the first pyrometer, a centering offset is added to the first distance; the substrate is then retracted from the chamber. And insert the substrate into the chamber by a second distance, the second distance being equal to the sum of the first distance and the centering offset.

12. A method for centering a substrate in a chamber, comprising the steps of: inserting the substrate into the chamber by a robotic arm, wherein the chamber includes a first pyrometer located below the substrate and a plurality of second pyrometers; determining incremental time values ​​of the plurality of second pyrometers relative to the first pyrometer; calculating time offsets of the incremental time values ​​relative to ideal incremental time values, wherein the ideal incremental time values ​​are the incremental time values ​​when the substrate is perfectly centered in a first direction perpendicular to the movement of the substrate; and finding a best match in a graph or a lookup table that correlates the time offset values ​​with a distance offset value, wherein the distance offset value is how far the substrate is from an off-center when perfectly centered in the first direction.

13. The method as described in claim 12, further comprising the steps of: retrieving the substrate; moving the substrate along the first direction by the distance offset value; and inserting the substrate into the chamber.

14. The method as described in claim 12, wherein the plurality of second pyrometers includes three pyrometers.

15. The method as described in claim 12, wherein the substrate is moved over the first pyrometer and the plurality of second pyrometers at a constant speed.

16. The method as described in claim 12, the method further comprising the step of: repeating the method a plurality of times.

17. The method as described in claim 16, wherein the method is stopped when the distance offset value is 0.25 mm or less.

18. A semiconductor processing tool, comprising: One chamber; A plurality of pyrometers are arranged along a bottom or top surface of the chamber; A plurality of lamps, the plurality of lamps being opposite to the plurality of pyrometers; a robotic arm for inserting a substrate into the chamber, wherein the robotic arm is movable in a first direction and a second direction, the second direction being perpendicular to the first direction; and a processor, wherein the processor includes instructions for centering the substrate in the chamber using readings from the plurality of pyrometers, wherein centering the substrate in the chamber is performed without opening the chamber.

19. The semiconductor processing tool as claimed in claim 18, wherein the robotic arm is configured to be taught to automatically place a specific substrate of the same size at the center of the chamber.

20. A semiconductor processing tool as claimed in claim 19, wherein waypoints are stored in the semiconductor processing tool for reuse in placing any additional substrates without using instructions for centering the substrates in the chamber using readings from the plurality of pyrometers.

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