Automated placement of substrate to center of chamber

Abstract

Embodiments disclosed herein include a method for centering a substrate in a chamber. In one embodiment, the method comprises the steps of: inserting a substrate by a robotic arm into a chamber; obtaining an increment time value of the second pyrometer relative to the first pyrometer, wherein the increment time value is the duration between the time when the first pyrometer is covered by the substrate and the time 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 an incremental time value when the substrate is fully 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 associates time offset values with distance offset values.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 866,315, filed on July 15, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of the present disclosure relate to the field of semiconductor processing, and more particularly to methods of centering a substrate within a chamber using a pyrometer. Background Art

[0004] In semiconductor manufacturing, it is critical to properly center the substrate within the chamber in order to provide highly uniform processing results. For example, in a thermal processing chamber, the substrate is ideally centered below an array of lamps. The lamps may be controlled in zones (e.g., a center zone, a middle zone, and an outer zone). Properly centering the substrate allows the zones to be properly oriented on the substrate in order to provide the desired heating for each zone.

[0005] The substrate is inserted into the chamber with a robotic arm (e.g., an end effector, etc.). The robotic arm is controlled by a processor. The processor provides instructions for moving the robotic arm within the chamber. For example, the robotic arm may include functionality to move the substrate in an X direction and a Y direction. As used herein, the X direction may be perpendicular to the direction of movement when the substrate is inserted into the chamber, and the Y direction may be parallel to the direction of movement when the substrate is inserted into the chamber.

[0006] The processor may include instructions for correctly placing the substrate. However, in some cases, the centering position may drift during use and / or after tool maintenance (e.g., planned maintenance (PM)). Therefore, the robot may need to be recalibrated in order to correctly center the substrate. Typically, this calibration is done manually. That is, a trained engineer or the like may be responsible for improving the centering of the substrate. This involves opening the chamber and visually checking the center position of the substrate. Opening the chamber is a time-consuming process because the chamber may need to be re-qualified and / or re-dried after opening. In addition, centering may be subject to human error. Therefore, existing centering techniques are not ideal for many semiconductor manufacturing processes. Summary of the invention

[0007] Embodiments disclosed herein include a method for centering a substrate in a chamber. In one embodiment, the method includes the following steps: inserting a substrate into the chamber by a robot; obtaining a delta time value for a second pyrometer relative to a first pyrometer, wherein the delta 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 value for the delta time value relative to an ideal delta time value, wherein the ideal delta time value is the delta time value when the substrate is perfectly centered in a first direction perpendicular to the motion of the substrate; comparing the time offset value to a chart or lookup table that relates the time offset value to a distance offset value, wherein the distance offset value is how far off-center the substrate is from being perfectly centered in the first direction; retracting the substrate; moving the robot in the first direction by the distance offset value; and inserting the substrate into the chamber by the robot.

[0008] Embodiments may also include a method of centering a substrate in a chamber, comprising the steps of inserting a substrate into a chamber by a robot, wherein the chamber includes a first pyrometer and a plurality of second pyrometers located below the substrate; determining incremental time values ​​for the plurality of second pyrometers relative to the first pyrometer; calculating a time offset value for 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 motion of the substrate; and finding a best match in a graph or lookup table that relates the time offset value to a distance offset value, wherein the distance offset value is how far off-center the substrate is from being perfectly centered in the first direction.

[0009] Embodiments may also include a semiconductor processing tool. In embodiments, the semiconductor processing tool includes: a chamber; a plurality of pyrometers, the plurality of pyrometers being arranged along a bottom or top surface of the chamber; a plurality of lamps, the plurality of lamps being opposite the plurality of pyrometers; a robot arm, the robot arm being used to insert a substrate into the chamber, wherein the robot 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 accomplished without opening the chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1A is a cross-sectional view of a semiconductor processing tool with a robot arm inserting a substrate according to an embodiment.

[0011] Figure 1B According to the implementation method Figure 1A Illustration of a plan view of a semiconductor processing tool in FIG.

[0012] Figure 1Cis a plan view illustration illustrating an XY robot plane defined by the scope of a robotic handler and an XY chamber plane parallel to the XY robot plane according to an embodiment.

[0013] Figure 2A is a diagram depicting the insertion of a substrate into a chamber, according to an embodiment, wherein the substrate is perfectly aligned in the X-direction.

[0014] Figure 2B is a graph illustrating a normalized pyrometer signal during insertion of a substrate into a chamber, according to an embodiment.

[0015] Figure 3A is a diagram depicting a perfectly centered substrate and a substrate having an offset in the X direction according to an embodiment.

[0016] Figure 3B is a graph of time offset values ​​and corresponding X-direction offsets according to an embodiment.

[0017] Figure 3C is a process flow diagram depicting a process for determining an offset of a substrate in the X-direction according to an embodiment.

[0018] Figure 4A is a diagram depicting a substrate inserted into a chamber in a manner that provides proper centering in the Y direction, according to an embodiment.

[0019] Figure 4B is a process flow diagram depicting a process for determining an offset of a substrate in the Y direction according to an embodiment.

[0020] Figure 5 is an icon of a block diagram of an exemplary computer system according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] Methods for centering a substrate within a chamber using a pyrometer are described herein. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent to those skilled in the art that the specific details are not required for the implementation of the embodiments. In other instances, well-known aspects are not described in detail to avoid unnecessarily obscuring the embodiments. Furthermore, it should be understood that the various embodiments shown in the drawings are illustrative representations and are not necessarily drawn to scale.

[0022] As described above, the current process for centering a substrate within a chamber involves manual intervention and opening the chamber. Therefore, the process is prone to human error and the chamber requires considerable downtime. Therefore, embodiments disclosed herein include substrate centering processes that can be implemented by a processor without opening the chamber. Specifically, embodiments utilize a pyrometer present in the chamber to detect the presence of a substrate. The position of the pyrometer relative to the center of the chamber is known. In this way, the edge of the substrate can be detected at multiple locations and multiple times. This allows the offset of the substrate relative to the center of the chamber to be calculated. Embodiments disclosed herein allow centering in the X direction and the Y direction.

[0023] In one embodiment, edge detection is possible due to the structure of the chamber. Multiple lamps can be arranged opposite to the pyrometer. For example, the lamps can be used to heat the substrate for thermal processing operations such as thermal oxidation, etc. In one embodiment, the lamps are kept on between the processing of different substrates so that the lamps remain warm. 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 heat signal from the lamp. Therefore, the signal from the pyrometer decreases. The reduction in signal can be used as an indication of the presence of a substrate edge. By monitoring the time when the various pyrometers detect the edge, the offset of the substrate can be determined.

[0024] Reference now Figure 1A , illustrates a cross-sectional view of a semiconductor processing tool 100 according to an embodiment. In an 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 an 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 an enclosure forming an interior space in which processing is performed.

[0025] 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 may provide heat energy to the interior space of the semiconductor processing tool 100 to process 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 interior region, a middle region, and an exterior region. However, it should be understood that embodiments may include any number of lamp regions (e.g., one or more regions).

[0026] In one embodiment, a plurality of pyrometers 120 may be disposed through the bottom 105 of the semiconductor processing tool 100. In the illustrated embodiment, for ease of illustration, all of the pyrometers 120A to 120D are illustrated in a single plane. However, it should be understood that the pyrometers 120 may be located in different planes from one another, such as Figure 1B As shown in the plan view of FIG. 1 , the pyrometer 120 receives a signal (e.g., a heat signal) from the lamp 113, as shown by the arrow. However, the signal to 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 FIG. Figure 1B shown.

[0027] In one embodiment, the substrate 101 can be inserted into the semiconductor processing tool 100. For example, a robot 110 (e.g., an end effector) can hold the substrate 101 and transfer the substrate 101 into the semiconductor processing tool 100. The robot 110 can place the substrate 101 within the edge ring 107. The robot 110 can include a plurality of robots in the X direction (entry and exit). Figure 1A plane) and Y direction ( Figure 1A The function of moving the substrate 101 on both sides of the substrate 101 (from left to right in the figure). In an embodiment, the substrate 101 can be any substrate suitable for semiconductor processing operations. In a specific embodiment, the substrate 101 can be a silicon wafer with any form factor (e.g., 300 mm, 450 mm, etc.). However, other semiconductor substrates 101 or any other material substrates 101 can also be used.

[0028] Reference now Figure 1B , illustrates a plan view of a semiconductor processing tool 100 according to an embodiment. In the illustrated embodiment, the cover 112 and the lamp 113 are omitted so that the substrate 101 and the pyrometer 120 can be clearly seen. As shown, the substrate 101 is inserted by the robot 110. When the substrate 101 is inserted into the semiconductor processing tool 100, the pyrometer 120 is covered. For example, in Figure 1B At the point in time shown, 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 was detected, the centering of the substrate 101 can be determined. A more detailed process of how the centering is calculated is provided in more detail below.

[0029] In the illustrated embodiment, a set of four pyrometers 120A-120D are illustrated. However, it should be understood that embodiments may utilize as few as two pyrometers to implement the centering operation. Additionally, more than four pyrometers 120 may be used. Increasing the number of pyrometers may allow the substrate 101 to be more accurately centered. For example, the center of the substrate may be set to an error as low as about 0.25 mm or less. Since the existing process is a manual process, such an error is considered acceptable because it is generally more accurate than the human error currently provided.

[0030] Reference now Figure 1C , illustrates a plan view (in the XY dimension) of a robot handler and chamber according to one embodiment. Specifically, the robot has an X 机器人 and Y 机器人 The plane 196 is defined by X and the chamber has 腔室 and Y 腔室 The robot blade 198 can move within the robot plane 196, and the robot plane 196 overlaps a portion of the chamber plane 197. In this way, the robot blade 198 can be inserted into the chamber 197.

[0031] It should be understood that placement is accomplished by mechanical blade 198 reaching X 机器人 ,y 机器人 The waypoints on the plane are completed, X 机器人 ,y 机器人 The plane is defined by the extent of the robot handler center and is parallel to the X 腔室 , Y 腔室 The waypoint of the chamber is taught to match the center of the chamber. This is done by finding the point X representing (0,0) on the chamber plane 197. 腔室 , Y 腔室 The robot plane value X 机器人 , Y 机器人 More generally, the process involves converting the robot's coordinate system (X 机器人 , Y 机器人 ) and the chamber coordinate system (X 腔室 , Y 腔室 ) This process is often referred to as "robot teaching".

[0032] Reference now Figure 2A , illustrates a diagram of edge detection over time according to an embodiment. Figure 2A In the illustrated embodiment, the substrate 201 is shown as being perfectly centered on the X-axis (up and down). This is considered an ideal situation for purposes of illustrating the edge detection process. Figure 2AAs shown, a series of substrate edges 201 are depicted as the substrate 201 moves through a semiconductor processing tool. 1 To 201 5 Each detected edge 201 1 To 201 4 Corresponds to the position of pyrometers 220A to 220D. Edge 201 5 is the ideal end position, where the center of the substrate is located at the center of the chamber L0 (ie, (0,0)). A more detailed description of how to implement Y-axis centering is provided in more detail below.

[0033] exist Figure 2A In the ideal case shown, the center point of the substrate 201 at each position (L1 to L4) 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 time 201 3 The center L4 of the substrate 201 is given by Equation 1:

[0034] Y(L4)=Y(220D)-(R 2 -X(220D) 2 ) 1 / 2 =-53.8Equation 1

[0035] Similar equations can be constructed using trigonometry to find the Y values ​​for other center points.

[0036] In an embodiment, the substrate 201 moves past the pyrometers 220A to 220D at a constant speed. The substrate may then be decelerated to move at time 201. 5 Therefore, the time difference between the positions L1 to L4 is proportional to the distance 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.

[0037] Reference now Figure 2B , illustrating the signal 221 detected by each pyrometer 1 To 221 4 A plot against time. Figure 2B The graph in is a normalized graph, with the maximum value being 1 and the minimum value being 0. As shown in the figure, each signal 221 1 To 221 4 There is a sharp drop at the point where the substrate covers the pyrometer. This is because the substrate blocks the thermal radiation from the lamp above, which is maintained at a constant power. Figure 2BAs shown, the time when the pyrometer is considered to be covered is the point at which the signal 221 passes the 0.5 mark of the signal strength. 1 To 221 4 The slope of the signal may not be uniform. For example, the signal 221 4 With a ratio signal 221 1 Smaller slope. This may be due to the location of the pyrometers. That is, pyrometers with X coordinates closer to 0 may have relatively steeper slopes than pyrometers with X coordinates farther from 0.

[0038] In the illustrated embodiment, each pyrometer is covered at a different time, such as t(L1), t(L2), t(L3), and t(L4). In order to relate each time to each other, one of the pyrometers is used as a reference point. For example, a delta time value (Δt) relative to the first time t(L1) is provided. That is, Equation 2 can be used to solve for the Δt value.

[0039] Δt(L2)=t(L2)-t(L1)=.05Equation 2

[0040] Similar equations can be provided to find Δt values ​​for other pyrometers.

[0041] Reference now Figure 3A , illustrating a fully centered substrate 301 according to an embodiment A and a substrate 301 offset by a distance dx B . Figure 3A This is to illustrate how to calculate the time offset value (dΔt(Ln)) for various X offsets. Figure 3A In the figure, the dx distance is 30 mm. First, calculate the ideal substrate 301 A The center point y(L2) of the offset substrate 301B is calculated using Equation 3.

[0042] y'(L2)=y(320B)-(R 2 -(x(320B)-dx) 2 ) 1 / 2 Equation 3

[0043] Similar equations can be provided for other L values ​​(L1, L3 and L4).

[0044] Thereafter, the Δy value (dy(Ln)) is calculated using Equation 4.

[0045] dy(Ln)=y'(Ln)-y(Ln) Equation 4

[0046] Since distance is proportional to time, the time associated with each increment y is given by Equation 5.

[0047] dt(Ln)=dy(Ln) / vEquation 5

[0048] In Equation 5, v is the velocity of the robotic arm. Finally, the time offset dΔt(Ln) can be provided by subtracting dt(L1) from the time associated with each other incremental y value. By varying the value of the offset dx, the time offset dΔt(Ln) can be determined for all values ​​of the offset dx. The values ​​can be stored as a chart or lookup table. In alternative embodiments, the time offset dΔt(Ln) can be determined by experimentation and / or machine learning.

[0049] Now refer to Figure 3B , illustrates a graph illustrating a plot of time offsets dΔt(L2), dΔt(L3), and dΔt(L4) and corresponding dx values ​​according to an embodiment. The circles represent the time offset values ​​calculated for the offset substrate. The time offset values ​​are fitted to the line to provide the most accurate dx value. For example, in Figure 3B , the time offset value corresponds to a dx of approximately 1.4 mm. Therefore, the robot arm needs to be offset by 1.4 mm to correct the centering of the substrate. Although illustrated in graphical form, it should be understood that a lookup table or the like may also be used to determine the offset dx. In addition, it should be understood that less than three time offset values ​​or more than three time offset values ​​may be used to determine the dx value. For example, a set of two pyrometers may be used to determine a single dΔt(L2) value that may be used to determine dx.

[0050] Now refer to Figure 3C , illustrates a process flow diagram according to an embodiment, which illustrates a process 380 for determining the offset of a substrate in a direction perpendicular to the motion of a robot. In the described process 380, a set of two pyrometers is used. However, it should be understood that more than two pyrometers may be used in some embodiments.

[0051] In one embodiment, process 380 begins at operation 381, which includes inserting a substrate into a chamber with a robotic arm. The chamber can be any suitable chamber having a heating lamp 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 an embodiment, the robotic arm can insert the substrate into the chamber in 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. That is, the robotic arm may have an offset in the X direction (i.e., perpendicular to the displacement direction of the robotic arm).

[0052] In an embodiment, process 380 may continue with operation 382, ​​which includes obtaining a delta time value for the second pyrometer relative to the first pyrometer. The delta time value may be the time between detecting an edge of the substrate with the first pyrometer and detecting an edge of the substrate with the second pyrometer. Detection of an edge of the substrate may be determined by observing the signals of the pyrometers. For example, when the substrate passes by the pyrometers, the signals may drop significantly, similar to Figure 2B In certain embodiments, edge detection may use the normalized midpoint of the pyrometer signal as the time when the pyrometer is considered covered.

[0053] In an embodiment, process 380 may continue with operation 383, which includes calculating a time offset value of the incremental time value relative to an ideal incremental time value. In an embodiment, the ideal incremental time value may be an incremental time value between the first pyrometer and the second pyrometer when the substrates are perfectly aligned. The ideal incremental time value may be a measured value stored in a memory, or the ideal incremental time value may be a calculated value stored in a memory.

[0054] In an embodiment, process 380 may continue at operation 384, which includes comparing the time offset value to a graph or lookup table that relates time offset values ​​to distance offset values. In an embodiment, when a graph is used, the graph may be similar to Figure 3B As described above, the chart or lookup table can be analytically generated and stored in a memory. In other embodiments, the chart or lookup table can be determined experimentally using a machine learning algorithm or the like. In an embodiment, the distance offset value is the distance that the substrate deviates from the true center in a direction perpendicular to the direction of travel of the substrate (i.e., in the X direction using the coordinate system described herein).

[0055] In one embodiment, process 380 may continue with 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.

[0056] In an embodiment, process 380 may continue with operation 386, which includes moving the robot arm by a distance offset value in a direction perpendicular to the direction of travel of the substrate entering and exiting the chamber. Ideally, the distance offset value may correct for misalignment of the substrate.

[0057] In an embodiment, process 380 may continue with operation 387, which includes inserting the substrate into the chamber with a robotic arm. Ideally, the alignment is now correct. However, it should be understood that the alignment may 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.

[0058] It should be appreciated that process 380 may be performed without human intervention. That is, a processor having access to pyrometer signals, values ​​stored in memory, etc. may automatically implement process 380. Process 380 may be performed after a preset number of substrates have been processed, after planned maintenance, or after any other desired duration or after other predetermined events.

[0059] Now refer to Figure 4A , illustrating a method for moving a substrate in a moving direction (ie, Figure 4A 1. An illustration of a method for centering in the Y direction (in the Y direction). In one embodiment, centering in the direction of motion is complicated by the fact that the speed of the substrate is not constant. That is, after passing the pyrometer, the robot must slow down 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.

[0060] When the substrate is properly aligned in the X direction, the substrate 401 is 1 The location of the center point L1 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 that falls on L0. When the normalized pyrometer signal is approximately 0.5, the first pyrometer 420A can be considered to be covered. If the signal strength is above or below 0.5 (or exceeds a threshold around 0.5), the deceleration process is adjusted and rechecked until the signal strength is 0.5 or within a 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 additional pyrometers (e.g., a second pyrometer 420B at position 4012).

[0061] Reference now Figure 4B , illustrates a process flow diagram explaining a process 490 for centering a substrate in a direction of motion (ie, the Y direction as described herein), according to one embodiment.

[0062] In an embodiment, process 490 begins with operation 491, which includes inserting a substrate into a chamber a first distance with a robotic arm so that the substrate stops at a first pyrometer. Operation 491 can begin after the substrate has been properly aligned in an 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 a starting point for the first distance. In an embodiment, the first distance can be traveled at a constant speed until the end of the first distance is approached. At this point, a deceleration process can be implemented to stop the substrate at the first pyrometer.

[0063] In an embodiment, process 490 may continue with operation 492, which includes determining whether the substrate is 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 be correctly stopped. If the substrate is not stopped at the desired position, operations 491 and 492 are repeated by changing the first distance and / or deceleration process until the correct position is obtained. If the pyrometer signal is greater than 0.5, a positive offset is provided, and 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, using the equation Y=v*t Figure 2B The time axis in is converted to Y values, where v is the velocity and t is the time.

[0064] In an embodiment, process 490 may continue with operation 493, which includes adding a centering offset to the first distance when the substrate is properly stopped 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 causes the end point 401E to be properly centered at the (0,0) coordinate (i.e., the center of the chamber).

[0065] In one embodiment, process 490 may continue with operation 494, which includes retrieving the substrate from the chamber. In one embodiment, the retrieving of the substrate may be opposite to the speed, acceleration, distance, etc. used to insert the substrate into the chamber.

[0066] In an embodiment, process 490 may continue with operation 495, which includes inserting the substrate into the chamber a second distance, the second distance being equal to the sum of the first distance and the centering offset. In addition, the acceleration and deceleration process used to find the centering offset may also be used in the insertion of the substrate. Therefore, the center point of the substrate should be located on L0 (i.e., (0,0)) or within the 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 centering offset may be used to determine the duration of the constant velocity (e.g., the centering offset distance is divided by the constant velocity to determine the additional duration for applying the constant velocity in order to land on (0,0)).

[0067] Figure 5 The diagrammatic representation of a machine in the exemplary form of a computer system 500 is shown, in which a set of instructions for causing the machine to perform any one or more of the methods described herein can be executed. In alternative embodiments, the machine can be connected (e.g., networked) to other machines in a local area network (LAN), an intranet, an extranet, or the Internet. The machine can be run as a server or client machine in a client-to-server network environment, or can be used as a peer machine in a peer-to-peer (or distributed) network environment. The machine can be a personal computer (PC), a tablet computer, a set-top box (STB), a personal digital assistant (PDA), a cellular phone, a web device, a server, a network router, a switch or a bridge, or any machine capable of executing a set of instructions specifying the action to be taken by this machine (sequentially or otherwise). In addition, although only a single machine is illustrated, the term "machine" should also be considered to include a collection of any machines (e.g., computers) that execute a set (or multiple sets) of instructions to perform any one or more methods described herein, either individually or jointly.

[0068] The exemplary computer system 500 includes a system processor 502, a 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.), a static memory 506 (e.g., flash memory, static random access memory (SRAM), etc.), and an auxiliary memory 518 (e.g., a data storage device) that communicate with each other via a bus 530.

[0069] The processor 502 represents one or more general-purpose processing devices, such as a microprocessor, a central processing unit, etc. More specifically, the 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. The processor 502 may also be one or more special-purpose processing devices, such as an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal system processor (DSP), a network system processor, etc. The processor 502 is configured to execute processing logic 526 to perform the operations described herein.

[0070] 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 generating device 516 (e.g., a speaker).

[0071] The secondary memory 518 may include a machine-accessible storage medium 532 (or more specifically, a computer-readable storage medium) on which is stored one or more sets of instructions (e.g., software 522) that embody any one or more of the methodologies or functions described herein. The software 522 may also reside, completely or at least partially, within the main memory 504 and / or within the processor 502 during execution by the computer system 500, the main memory 504 and the processor 502 also constituting machine-readable storage media. The software 522 may also be transmitted or received over the network 520 via the network interface device 508.

[0072] Although the machine-readable storage medium 532 is shown as a single medium in the exemplary embodiment, the term "machine-readable storage medium" should be considered to include a single medium or multiple media (such as 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 to include any medium capable of storing or encoding a set of instructions to be executed by a machine and causing the machine to perform any one or more of the methods of the present disclosure. Therefore, the term "machine-readable storage medium" should be considered to include, but is not limited to, solid-state memories, and optical and magnetic media.

[0073] According to an embodiment of the present disclosure, a machine-storable storage medium has instructions stored thereon that cause a data processing system to perform a method for centering a substrate in a chamber using a pyrometer. The method includes measuring a delta time value between a cover of a first pyrometer and a cover of a second pyrometer. The method includes calculating a time offset value of the delta time value relative to an ideal delta time value. The method includes comparing the time offset value to a chart or lookup table that associates the time offset value with a distance offset value. The method includes retracting the substrate, adjusting the robotic arm by the distance offset value, and reinserting the substrate into the chamber.

[0074] Thus, a method of centering a substrate using pyrometer data is disclosed.

Claims

1. A method for centering a substrate in a chamber, comprising the steps of: inserting the substrate into the chamber by a robot arm; obtaining a delta time value for a second pyrometer relative to a first pyrometer, wherein the delta 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 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 motion of the substrate; comparing the time offset value to a graph or lookup table that relates the time offset value to a distance offset value, wherein the distance offset value is how far off-center 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 The substrate is inserted into the chamber by the robot. 2 . The method of claim 1 , wherein the robot has a constant speed in the first direction as the substrate passes by the first pyrometer and the second pyrometer.

3. The method of claim 1, wherein the graph or the lookup table is obtained through experiments and machine learning, or is calculated analytically.

4. The method of claim 1 , wherein the first pyrometer has a first normalized pyrometer signal between 0 and 1 and the second pyrometer has a second normalized pyrometer signal between 0 and 1, and wherein the first pyrometer and the second pyrometer are considered covered when the normalized signals pass 0.

5. 5 . The method of claim 4 , wherein a slope of the first normalized pyrometer signal is different than a slope of the second normalized pyrometer signal.

6. The method of claim 1, further comprising the steps of: The method is repeated one or more times.

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

8. The method of 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 for 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 time offsets of the second and third 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 the first direction; and The time offset value is compared to the graph or the lookup table that relates the time offset value to the distance offset value, wherein the distance offset value is how far off-center the substrate is from being perfectly centered in the first direction.

10. The method of claim 1, further comprising the steps of: After centering the substrate in the first direction, the substrate is centered in a second direction parallel to the movement of the substrate.

11. The method of claim 10, wherein centering the substrate in the second direction comprises the steps of: inserting the substrate into the chamber by the robot arm for a first distance so that the substrate stops at the first pyrometer; determining whether the substrate is properly stopped at the first pyrometer; adding a centering offset to the first distance when the substrate is properly stopped at the first pyrometer; retrieving the substrate from the chamber; and The substrate is inserted into the chamber a second distance equal to the first distance plus the centering offset.

12. A method of centering a substrate in a chamber, comprising the steps of: inserting the substrate into the chamber by a robot, wherein the chamber includes a first pyrometer and a plurality of second pyrometers located below the substrate; determining delta time values ​​for 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 motion of the substrate; and A best match is found in a graph or lookup table that relates time offset values ​​to distance offset values, where the distance offset value is how far off-center the substrate is from being perfectly centered in the first direction.

13. The method of claim 12, further comprising the steps of: retracting the substrate; moving the substrate along the first direction by the distance offset value; and The substrate is inserted into the chamber.

14. The method of claim 12, wherein the second plurality of pyrometers comprises three pyrometers.

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

16. The method of claim 12, further comprising the steps of: The method was repeated multiple times.

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

18. A semiconductor processing tool comprising: Chamber; a plurality of pyrometers arranged along a bottom or top surface of the chamber; a plurality of lamps, the plurality of lamps opposing the plurality of pyrometers; a robot arm, the robot arm being used to insert a substrate into the chamber, wherein the robot 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 a substrate in the chamber using readings from the plurality of pyrometers, wherein centering the substrate in the chamber is accomplished without opening the chamber.

19. The semiconductor processing tool of claim 18, wherein the robot arm is configured to be taught to automatically place specific substrates of the same size in the center of the chamber.

20. The semiconductor processing tool of claim 19, wherein waypoints are stored in the semiconductor processing tool for reuse to place any additional substrates without using the instructions for centering a substrate in the chamber using readings from the plurality of pyrometers.

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