Semiconductor wafer transfer monitoring device

Abstract

A semiconductor wafer transfer monitoring apparatus includes measuring vibration of an element during transfer of a semiconductor wafer. The measured vibrations are analyzed to detect collisions or scratches of the semiconductor wafer during transfer. In response to detecting a collision or scratch of the semiconductor wafer, at least one remedial action is performed, such as outputting a notification of a collision or scratch or stopping transfer of the semiconductor wafer. The element to measure its vibration may be a wafer transfer robot used in transfer. Analysis of the measured shocks may include inputting the measured shocks to an artificial intelligence (AI) algorithm trained to detect collisions or scratches of the semiconductor wafer.

Description

Technical Field

[0001] This disclosure relates to a semiconductor wafer transport monitoring device and a semiconductor wafer transport monitoring method. Background Technology

[0002] The following involves semiconductor manufacturing technology, semiconductor wafer delivery technology, and related technologies. Utility Model Content

[0003] According to some embodiments of this disclosure, a semiconductor wafer transport monitoring device operates in conjunction with an associated semiconductor wafer transport device. The semiconductor wafer transport monitoring device includes: a vibration sensor operatively connected to measure vibration data of elements of the associated semiconductor wafer transport device during semiconductor wafer transport operations; and an electronic processor programmed to analyze the measured vibration data to detect problems in the semiconductor wafer transport and to perform at least one remedial action in response to the detection of such problems.

[0004] According to some embodiments of this disclosure, a semiconductor wafer transport monitoring method includes: measuring vibration of an element during the transport of a semiconductor wafer; analyzing the measured vibration to detect a collision or scratch on the semiconductor wafer during transport; and performing at least one remedial action in response to the detection of a collision or scratch on the semiconductor wafer.

[0005] According to some embodiments of this disclosure, a semiconductor wafer transfer apparatus includes: a wafer transfer robot configured to transfer a semiconductor wafer between a wafer carrier and a semiconductor wafer processing or characterization tool; a vibration sensor for measuring vibrations of the wafer transfer robot; and an electronic processor programmed to detect problems in the transfer of the semiconductor wafer performed by the wafer transfer robot by analyzing the vibrations of the wafer transfer robot measured by the vibration sensor during transfer.

[0006] To make the above-described features and advantages of this disclosure more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0007] The various aspects of this disclosure are best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, in accordance with industry standard practice, the various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of explanation.

[0008] Figure 1 This schematically illustrates the combination of a semiconductor wafer transport monitoring device and a semiconductor wafer transport device.

[0009] Figure 2 An automated semiconductor wafer transport monitoring method is illustrated schematically.

[0010] Figure 3 as well as Figure 4 The diagram illustrates some vibration patterns that may be characteristic of various problems.

[0011] Figure 5 Another non-limiting illustrative embodiment of vibration analysis in an automated semiconductor wafer transport monitoring method is shown schematically.

[0012] Explanation of reference numerals in the attached figures

[0013] 10: Chip Delivery Robot

[0014] 12: Base

[0015] 14: Robotic Arm

[0016] 16: Loading Port

[0017] 18: Front-opening chip transfer box, FOUP

[0018] 20: Slot

[0019] 22: Chip

[0020] 30, 31: Vibration sensors

[0021] 32: Electronic Processor

[0022] 34, 35, 36: Transceivers

[0023] 37: Vibration data

[0024] 38: Battery

[0025] 40: Analysis

[0026] 42: Chip Transfer Problem Solver

[0027] 43: Collision

[0028] 44: Notice

[0029] 46: Output devices

[0030] 48: Signal

[0031] 50: Control Data

[0032] 60, 62, 64, 66, 70, 72, 74, 76, 78: Operation

[0033] 64-1, 64-2, 64-3: Detection Operations

[0034] 70-1, 70-2, 70-3: Decision-making operations

[0035] 72-1, 72-2, 72-3: Remedial Actions Detailed Implementation

[0036] The following disclosure provides several different embodiments or instances for implementing various features of the provided subject matter. Specific examples of elements and arrangements are described below to simplify this disclosure. Of course, these elements and arrangements are merely examples and are not intended to be limiting. For example, in the following description, the formation of a first feature over or on a second feature may include embodiments where the first and second features are formed in direct contact, and may further include embodiments where additional features may be formed between the first and second features such that the first and second features are not in direct contact. Additionally, reference numerals and / or letters may be repeated in various instances of this disclosure. Such repetition is for simplicity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0037] Furthermore, for ease of description, spatially related terms such as “below,” “under,” “lower,” “above,” “upper,” etc., may be used herein to describe the relationship between one element or feature and another element or feature as shown in the figures. In addition to the orientations depicted in the figures, spatially related terms are intended to cover different orientations of the device in use or operation. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly. The terms “first,” “second,” “third,” “fourth,” etc., are merely general designations and are therefore interchangeable in various embodiments. For example, while an element (e.g., an opening) may be referred to as a “first” element in some embodiments, it may be referred to as a “second” element in other embodiments.

[0038] In a semiconductor foundry, batches of wafers are typically moved in wafer carriers (such as front-opening unified pods, FOUPs) designed to be compatible with a range of different semiconductor processing or characterization tools. In a typical semiconductor wafer handling workflow for manufacturing integrated circuits (ICs), the semiconductor processing or characterization tool (generally referred to herein as the "tool") includes a loading port. Overhead transport (OTT) or other automated transport systems move the FOUP or other wafer carrier to the tool's loading port, and a wafer transfer robot transfers semiconductor wafers between the FOUP or other wafer carrier and the tool for processing or characterization. By way of some non-limiting illustrative examples, a foundry's semiconductor processing or characterization tools may include plasma etching tools, chemical vapor deposition (CVD) and / or physical vapor deposition (PVD) tools, photoresist spin coaters, photoresist developing tools, microscopy tools, and / or the like.

[0039] This type of automated workflow offers numerous advantages, such as increased wafer throughput, ensuring consistent handling of all semiconductor wafers in a batch, reducing wafer damage due to improper handling, and minimizing wafer contamination by human factory workers. However, automated wafer transfer can encounter various types of malfunctions, such as collisions between wafers and FOUPs or other wafer carriers or tools, scratches on wafers during transfer, tilting insertions or removals of semiconductor wafers transferred by the wafer transfer service, and / or similar issues. While the incidence of automated wafer transfer malfunctions is generally low, such failures can lead to wafer scrap or other types of IC yield reductions, and may also damage expensive, precision factory equipment.

[0040] Furthermore, when automated wafer transfer failures do occur, they are sometimes caused by system problems with the wafer transfer equipment, such as misalignment between the wafer transfer robot and the loading port. In such cases, continued operation of the automated wafer transfer system will damage every wafer handled by the wafer transfer robot until the problem is identified. If there is a significant delay between the occurrence of the problem and its identification, it can lead to substantial costs due to the damage of consecutive wafers.

[0041] One way to identify wafer delivery problems is by analyzing the wafer to detect the damage caused by the problem. This analysis can be challenging because damage to a semiconductor wafer that necessitates scrapping an IC being manufactured may not be visually detectable. Therefore, automated wafer defect inspection systems can be inserted into the IC manufacturing workflow at strategic points. These systems can employ techniques such as electron beam (e-beam) inspection to detect wafer defects that are invisible to the human eye (but still require scrapping). However, this method does not identify the problem when it occurs during wafer delivery. Instead, it identifies the problem only later in the workflow using the defect inspection system, and even then, the forensic analysis to identify the root cause of the wafer delivery problem can be cumbersome and time-consuming. Similarly, offline particle or photoresist monitoring may detect the problem, but this also occurs some point downstream of the origin of the wafer delivery problem in the IC manufacturing workflow; again, determining the root cause of the wafer delivery problem involves cumbersome and time-consuming forensic analysis.

[0042] This document discloses various embodiments of a semiconductor wafer transport monitoring device and a method for providing direct and near-instantaneous detection of problems in wafer transport. The disclosed method includes setting up or operably connecting a vibration sensor during semiconductor wafer transport performed by the semiconductor wafer transport device to measure vibration data of a wafer transport robot or another component of the semiconductor wafer transport device. An electronic processor is programmed to analyze the measured vibration data to detect problems in the semiconductor wafer transport and, in response to the detection of a problem, to perform at least one remedial action.

[0043] As a mechanical system comprising servo motors and numerous moving components, semiconductor wafer transport equipment typically exhibits significant vibration during normal operation. Therefore, detecting vibration alone does not necessarily indicate a wafer transport problem. However, as disclosed herein, through appropriate analysis, the vibration measured as a result of a wafer transport problem can be distinguished from the vibration generated by the wafer transport equipment during its normal operation. Furthermore, in some embodiments disclosed herein, the type of wafer transport problem (e.g., collisions relative to wafer scratch formation relative to tilted wafer insertion or removal) can be differentiated through analysis of the measured vibration.

[0044] The disclosed semiconductor wafer transport monitoring equipment and methods offer numerous advantages. They provide near real-time detection of wafer transport problems, detecting them either when they occur or immediately afterward, before the wafer transport is completed. This allows for immediate remedial action, such as stopping the wafer transport. This prevents faulty wafer transport operations from continuing to the point where they could cause costly damage to the wafer transport equipment.

[0045] Another advantage of the disclosed wafer transport monitoring equipment and method is that immediately stopping the wafer transport operation in response to the detection of a wafer transport problem (or, in some embodiments, immediately notifying the manufacturing plant workers) ensures that the source of the wafer transport problem is identified and repaired before the wafer transport equipment processes another semiconductor wafer. This limits the failure cost of the wafer transport equipment to scrapping (at most) a single semiconductor wafer. In fact, the near real-time detection of wafer transport problems and the immediate cessation of wafer transport can even allow the wafer itself to be at least partially salvaged. For example, if the real-time wafer transport monitoring disclosed herein detects the onset of wear that causes wafer scratches and immediately stops the wafer transport, only the portion of the wafer at or near the initial wafer scratch may be lost.

[0046] Another advantage of the disclosed wafer transport monitoring device and method is that it directly detects wafer transport problems. Unlike methods that rely on subsequent inspections to detect wafer damage and forensic analysis to trace the source of damage back to the wafer transport problem, the disclosed wafer transport monitoring device and method directly identify wafer transport problems, and in some embodiments, can even identify the type of problem (e.g., collisions, scratch formation, tilted wafer insertion or removal, etc.).

[0047] Another advantage of the disclosed wafer transfer monitoring equipment and methods is that they do not introduce additional steps into the IC manufacturing process workflow. For example, the disclosed wafer transfer monitoring equipment and methods do not require additional wafer inspection steps.

[0048] Another advantage of the disclosed wafer transport monitoring devices and methods is their ease of retrofitting to existing semiconductor wafer transport equipment. For example, in some embodiments, the vibration sensor is battery-powered and includes a wireless transmitter or transceiver for transmitting measured vibration data to a computer or other electronic processor that performs vibration analysis. In this case, retrofitting only requires attaching the battery-powered wireless vibration sensor to the wafer transport robot or another suitable component of the wafer transport equipment and loading suitable vibration data acquisition and analysis software onto the computer in the semiconductor manufacturing plant.

[0049] Now for reference Figure 1 The image shows a semiconductor wafer transport monitoring device and the monitored wafer transport device.

[0050] Figure 1 An exemplary wafer transfer device is used to transfer a wafer to a semiconductor processing or characterization tool (i.e., a "tool"). Figure 1 (not shown in the image) or from semiconductor processing or characterization tools (i.e., "tools") Figure 1(Not shown) The device for transferring wafers includes a wafer transfer robot 10 with a base 12 and a robotic arm 14. The robotic arm 14 may include a horizontal sliding section, as shown, or may be a more complex articulated robotic arm with multiple joints, etc. The wafer transfer device further includes a loading port 16 with sockets, etc., the size and shape of which are designed to receive the illustrative front-opening wafer transfer cassette (FOUP) 18 or other wafer carriers. In a semiconductor manufacturing plant, overhead conveyor (OHT, not shown) or other automated transport systems transport the FOUP 18 (or other wafer carriers) to the loading port 16 of a tool, and after processing or characterizing the semiconductor wafer carried by the FOUP, the FOUP 18 is removed from the loading port 16 (typically transferring the FOUP to the next tool in the manufacturing plant in the IC processing workflow). As shown, the FOUP 18 includes a set of slots 20, each slot 20 being sized and shaped to receive and hold the semiconductor wafer. FOUP 18 can hold as many semiconductor wafers as it has slot 20, and a group of wafers held by FOUP 18 may be referred to as a wafer batch in some terms. (Illustrative) Figure 1 A single semiconductor wafer 22 is shown in the process of removal (or, alternatively, insertion) from slot 20 of FOUP 18. After removal of wafer 22 from FOUP 18, wafer transfer robot 10 then moves the wafer to a tool (not shown) and loads it into the tool for processing or characterization. After processing or characterization is complete, wafer transfer robot 10 removes the semiconductor wafer from the tool and moves the wafer back to FOUP 18 and inserts it into slot 20 of FOUP 18.

[0051] It should be understood that successful removal of the wafer 22 from slot 20 of FOUP 18 and subsequent (re)insertion of the wafer into slot 20 of FOUP 18 requires proper and precise alignment between the wafer transfer robot 10 and the FOUP 18 located on port 16. Similarly, although not shown, it should be understood that successful insertion of the wafer 22 into the tool and subsequent removal of the wafer from the tool requires proper and precise alignment between the wafer transfer robot 10 and the tool. This alignment is typically achieved first through a manual process, in which the individual components 12, 16 are flattened, height-adjusted, rotated, etc. Afterward, alignment is generally expected to remain for a considerable period. However, various mechanisms can cause the wafer transfer equipment (or its components) to become misaligned, potentially leading to problems in the wafer transfer operation. Such misalignment can be introduced in a variety of ways, such as due to seismic activity, settling of various components (e.g., the wafer transfer robot 10 may be a heavy component that gradually shifts its position over time due to gravity), movement of components caused by vibrations introduced during the normal operation of the wafer transfer robot 10 or other components, vibrations generated during the normal operation of semiconductor processing or characterization tools, human intervention (e.g., a manufacturing worker bumping into the wafer transfer robot 10), etc. Furthermore, specific wafer transfer problems may arise from structural defects in the FOUP 18, such as a bent slot 20 or the arriving semiconductor wafer being placed in the slot 20 in an incorrect (tilted) position. These are merely some non-limiting illustrative examples of some possible root causes of wafer transfer problems.

[0052] It should also be noted that the exemplary wafer transfer device, including the exemplary wafer transfer robot 10 and loading port 16, is merely a non-limiting example. More generally, a given wafer transfer device may include various mechanisms for transferring semiconductor wafers, such as sliding mechanisms (as shown in robotic arm 14), articulated arm mechanisms, moving tracks, trajectories, and / or the like. Generally, wafer transfer devices include mechanical moving parts, typically driven by electric motors (servo motors, stepper motors, etc.), driving mechanical linkages, tracks, arms, etc., to remove semiconductor wafers from a wafer carrier, transfer wafers to semiconductor processing or characterization tools, insert wafers into tools for processing or characterization, then reverse the process to return wafers to the wafer carrier. In some more complex workflow settings (not shown), a first wafer transfer device may transfer wafers from a wafer carrier to a first tool, a second wafer transfer device may transfer wafers directly from the first tool to a second tool, and a third wafer transfer device may transfer wafers from the second tool back to the wafer carrier. This extended workflow setup can be extended to combine three or more tools, and in some cases, various wafer transfer devices can be configured to transfer wafers between two, three, or more tools in a programmed sequence within a tool cluster. These are merely further, non-limiting examples. The semiconductor wafer transfer monitoring devices and methods disclosed herein can be used to monitor any such wafer transfer devices.

[0053] Continue to refer to Figure 1 The illustrative semiconductor wafer transfer monitoring device includes a vibration sensor 30 and a computer or other electronic processor 32. The vibration sensor 30 is operatively connected to measure vibration data of the wafer transfer robot 10 or another component of the semiconductor wafer transfer device (e.g., such as...) during semiconductor wafer transfer operations. Figure 1 The loading port 16 is shown via an alternative vibration sensor 31. An exemplary vibration sensor 30 is mounted on the component's robotic arm 14 or wafer transfer robot 10. This placement of the vibration sensor 30 has certain advantages. The wafer transfer robot 10 (more specifically, its robotic arm 14) participates in each stage of the wafer transfer process (e.g., removing the wafer from FOUP 18, transferring it to a tool, inserting the wafer into the tool, and the reverse process to return the wafer to FOUP 18). The wafer transfer robot 10 (especially its robotic arm 14) may also experience strong vibrations in response to problems such as wafer collisions, wafer scratch formation, or tilting of the wafer 22 during insertion or removal from the slot 20 of FOUP 18. This is because the robotic arm 14 directly handles the semiconductor wafer 22.

[0054] However, it is conceivable to use other operative connections of the vibration sensor 30 to measure vibration data. For example, the vibration sensor could be mounted on the base 12 of the wafer transfer robot 10, or it could be mounted on the loading port 16. The advantage of mounting the vibration sensor on the loading port 16 is that it will be highly sensitive to vibrations caused by misplacement of the FOUP 18 on the loading port 16, which could be a source of wafer transfer problems. Placing the vibration sensor on the base 12 of the wafer transfer robot 10 has certain advantages in mechanically filtering out normal vibrations from the robotic arm. It should also be noted that, although... Figure 1 A single vibration sensor 30 is shown mounted on the robotic arm 14 of the wafer transfer robot 10; however, it is contemplated that two or more vibration sensors mounted on different components of the wafer transfer device could be included to increase wafer sensitivity and / or the types of wafer transfer problems that can be detected. For example, adding a second vibration sensor mounted on the loading port 16 could facilitate the detection of misalignment of the FOUP 18 at the loading port 16. In contrast, if only a single exemplary vibration sensor 30 is provided on the robotic arm 14, such FOUP misalignment would only be detected if the robotic arm 14 fails to cleanly remove the wafer from the slot 20 of the FOUP 18.

[0055] The vibration sensor 30 can be any type of sensor capable of generating an output in response to vibration. In some embodiments, the vibration sensor 30 includes an accelerometer (e.g., a three-dimensional accelerometer). In such embodiments, the accelerometer-based vibration sensor 30 detects vibrations caused by acceleration applied to the accelerometer of the vibration sensor 30, which converts the vibration into an electrical signal. In other embodiments, the vibration sensor 30 may include a piezoelectric crystal. In such embodiments, vibration applies mechanical stress to the piezoelectric crystal, which acts as a transducer that converts the stress into an electrical signal. In other embodiments, the vibration sensor 30 may include an eddy current sensor or a capacitive displacement sensor. In such embodiments, vibration induces eddy currents or causes periodic changes in the conductor spacing of the capacitive displacement sensor, converting the vibration into an electrical signal. In other embodiments, the vibration sensor 30 may include a laser displacement-based vibration sensor, wherein vibration alters the optical path of a laser / optical detector pair to convert the vibration into an electrical signal. Further contemplated embodiments of the vibration sensor 30 include strain gauge-based vibration sensors, acoustic vibration sensors, gyroscope vibration sensors, and so on. These are merely some non-limiting illustrative examples of suitable embodiments of the vibration sensor 30, and more generally, the vibration sensor 30 can employ any suitable transducer technology operable to convert vibrations into electrical signals.

[0056] An exemplary electronic processor 32 is a computer 32; however, another electronic processor may also be conceived, such as an electronic controller equipped with a microprocessor. The computer 32 is appropriately programmed, as disclosed herein, to analyze vibration data acquired by the vibration sensor 30 to detect problems in wafer transfer performed by the wafer transfer devices 10, 16, such as wafer collision, wafer scratch formation, wafer tilting insertion / removal, or the like.

[0057] For coordinated operation, vibration data acquired by vibration sensor 30 is transmitted to electronic processor 32 for analysis. In an illustrative embodiment, this is achieved by: a wireless transmitter or transceiver 34 connected to, integrated with, or operably communicating with vibration sensor 30 (and / or a similar (analogous) wireless transmitter or transceiver 35 connected to, integrated with, or operably communicating with an additional or alternative vibration sensor 31) and a wireless receiver or transceiver 36 connected to, integrated with, or operably communicating with electronic processor 32. The wireless transmitter or transceiver 34 and the wireless receiver or transceiver 36 appropriately utilize common wireless communication protocols (such as Bluetooth). TM WiFi TM Zigbee TM Vibration data 37 is transmitted from vibration sensor 30 to electronic processor 32 (e.g., etc.). In some embodiments, low-power Bluetooth is advantageously used. TM Or Zigbee TM Low-power protocols are used to minimize power consumption for transmission at vibration sensor 30. In such embodiments, vibration sensor 30 may be battery-powered, such as... Figure 1 This is schematically indicated by an exemplary battery 38. Although Figure 1 The wireless transmitter or transceiver 34 and battery 38 are schematically shown as separate components from the vibration sensor 30. However, in some embodiments, the transmitter or transceiver 34 and battery 38 can be integrated with the vibration sensor 30. For example, there can be a single housing housing an accelerometer, the piezoelectric crystal or other vibration sensing element of the vibration sensor 30, and also housing the transmitter or transceiver 34 and battery 38, such that the combination 30, 34, 38 is constructed as a single, integrated wireless, battery-powered vibration sensor 30. In this case, the wireless, battery-powered vibration sensor 30 is a standalone unit that is physically attached to the robotic arm 14 of the wafer transfer robot 10 by adhesive, fasteners (e.g., screws, bolts, etc.), tape, etc. This is advantageous for retrofitting the wafer transfer devices 10, 16 with wafer transfer monitoring equipment, since there is no electrical connection between the wafer transfer monitoring equipment and the wafer transfer devices 10, 16, and it is advantageous for attaching the vibration sensor 30 to the wafer transfer devices 10, 16 without requiring substantial modification to the latter.

[0058] While the illustrative embodiment employs wireless communication between the vibration sensor 30 and the electronic processor 32, a wired connection is also contemplated. Similarly, although battery-powered vibration sensors 30, 38 are shown, it is alternatively contemplated that the vibration sensors be powered by a wired power supply (e.g., connected to AC power at the manufacturing plant). As another contemplated example, in a non-retrofit configuration, the vibration sensor 30 could be integrated into the wafer transport robot (e.g., housed within a housing of robot components), and in such an implementation, the vibration sensor could draw power from the robot itself and connect to the robot's wired or wireless communication interface to transmit vibration data to the electronic processor 32. In a more tightly integrated configuration, the electronic processor 32 could be implemented within a microprocessor-based built-in robot controller of the wafer transport robot, allowing for full integration of the wafer transport monitoring equipment with the wafer transport robot.

[0059] As previously stated, the electronic processor 32 is programmed to perform analysis 40 of the measured vibration data received from the vibration sensor 30 (e.g., via...). Figure 1 The illustrative example includes wireless communication elements 34 and 38 to detect problems in semiconductor wafer delivery and implements a wafer delivery problem remediator 42 to perform at least one remedial action in response to detecting a problem in semiconductor wafer delivery. For example, in a non-limiting illustrative example of analysis 40, the electronic processor 32 may be programmed to analyze measured vibration data to detect problems in semiconductor wafer delivery by comparing the measured vibration data with reference vibration data representing successful semiconductor wafer delivery. Figure 1 In this context, the chip transfer problem is schematically indicated by a collision 43, which is schematically indicated between the semiconductor chip 22 and the slot 20 of the FOUP 18.

[0060] Analysis 40 of the measured vibration data used to detect wafer transport problems can employ various methods. This analysis is challenging because, as previously mentioned, wafer transport devices 10, 16 typically experience normal vibrations during normal operation due to the normal contact between the wafer 22 and components such as the slot 20 of FOUP 18, the wafer container of semiconductor processing or characterization tools, the mechanical movement of robotic arms 14, and / or similar elements. Vibrations may also originate from other sources, such as vacuum pumps or other components of the tooling. Therefore, in the illustrative embodiment, analysis 40 is implemented as an artificial intelligence (AI)-based wafer transport problem detector 40. AI algorithms or classifiers (e.g., artificial neural network (ANN), support vector machine (SVM) classifiers, or other AI algorithms or classifiers) can be trained to distinguish vibrations caused by collisions, scratches, tilted wafer placement, or the like from normal vibrations that occur during normal operation of the wafer transport devices 10, 16. While AI algorithms or classifiers are used in illustrative analysis 40, other types of analysis can be envisioned to detect wafer delivery problems, such as deriving vibration characteristics (e.g., vibration amplitude metrics, frequency metrics, etc.) and determining the presence of wafer delivery problems based on these vibration metrics.

[0061] In some embodiments, remedial action 42 performed in response to the detection of a wafer delivery problem includes issuing a warning or notification 44 (these terms are used synonymously herein) on an appropriate output device 46 (e.g., an illustrative computer or workstation 46). For example, the warning or notification 44 may be a textual notification describing the detected wafer delivery problem. Alternatively or additionally, the warning or notification 44 may be output to an IC manufacturing process workflow log.

[0062] In some embodiments, remedial action 42 performed in response to the detection of a wafer transfer problem additionally or alternatively includes stopping the wafer transfer operation performed by the wafer transfer devices 10, 16. In some embodiments, this is performed by sending a stop or halt transfer signal 48 from the electronic processor 32 to the wafer transfer robot 10 (in an illustrative example; or more generally, to the controller element of the wafer transfer device), causing the wafer transfer device to immediately stop wafer transfer. As previously stated, immediately stopping wafer transfer in response to the detection of a wafer transfer problem can minimize damage to the hardware of the wafer transfer device and may even allow the wafer 22 undergoing transfer to be completely or partially salvaged.

[0063] In the examples described so far, the wafer transport problem detector 40 performs an operation that analyzes only the vibration data provided by the vibration sensor 30. In some embodiments, the vibration data is the sole input for detecting wafer transport problems.

[0064] Continue to refer to Figure 1 In other embodiments, the wafer transfer problem detector 40 performs analysis on vibration data provided by the vibration sensor 30 and also on control data 50 related to semiconductor wafer transfer performed by the wafer transfer devices 10, 16. For example, the control data 50 may be provided by the wafer transfer robot 10. If such control data 50 is provided, this additional information can be used to better distinguish between vibrations caused by wafer transfer problems and normal vibrations. Alternatively, the control data 50 can be used to classify the type of wafer transfer problem. For example, if a vibration identified as indicating a wafer transfer problem occurs when the control data 50 indicates that a wafer is being removed from FOUP 18, the wafer transfer problem can be classified as related to abnormal contact between wafer 22 and slot 20. FOUP 18, as another example, if a vibration identified as indicating a wafer transfer problem occurs when the control data 50 indicates that a wafer is being loaded into a semiconductor processing or characterization tool, the wafer transfer problem can be classified as related to abnormal contact between wafer 22 and the tool.

[0065] Now for reference Figure 2 An exemplary wafer transport monitoring method is described. This method can be, for example, by... Figure 1 The wafer transfer monitoring equipment (e.g., consisting of vibration sensor 30 and electronic processor 32) performs the operation. In operation 60, vibration data is measured by vibration sensor 30 while wafer transfer robot 10 performs wafer transfer. In operation 62, vibration data is extracted in a sliding window. In operation 64, AI-based wafer transfer problem detection is applied to the vibration data in each window of the vibration data extracted in operation 62. For example, operation 64 can use the previously described AI-based wafer transfer problem detector 40.

[0066] Alternatively, in operation 66, real-time data indicating the current stage of wafer transfer is received. For example, operation 66 may receive control data 50 provided by the wafer transfer robot 10. The control data 50 is appropriately timestamped or otherwise time-aligned with the vibration data in each window of the vibration data. In embodiments employing optional operation 66, the received real-time data indicating the current stage of wafer transfer is utilized in operation 64 to improve the accuracy and / or classification of wafer transfer problems. In one approach, the real-time data indicating the current stage of wafer transfer (or the current stage extracted from real-time data) may be input along with the vibration data in the window into an AI-based wafer transfer problem detector 40, which is trained to operate on the combination of the vibration data and this additional data.

[0067] In another approach, the AI-based wafer transport problem detector 40 operates only on vibration data, and if the AI-based wafer transport problem detector 40 detects a problem in semiconductor wafer transport, it instructs the use of real-time data of the current stage of wafer transport (or the current stage extracted from real-time data) to classify the type of problem according to the wafer transport stage in which the problem occurred.

[0068] In operation 70, a decision is made based on the output of operation 64 to determine whether a wafer transfer problem has been detected. If a wafer transfer problem is detected in operation 70, the process proceeds to operation 72, where appropriate remedial action is performed. Remedial action may include presenting a human-perceptible collision warning (e.g., as a real-time warning displayed on a controller monitor and / or as a log entry in a workflow monitoring system and / or the like). If the AI-based wafer transfer problem detector 40 (or optionally, subsequent analysis of real-time data indicating the current stage of wafer transfer) determines the type of wafer transfer problem, the output human-perceptible warning may also include information about the type of wafer transfer problem detected.

[0069] The remedial action performed in operation 72 may additionally or alternatively include stopping wafer transport, for example by sending an abort or stop transport signal 48 from the electronic processor 32 to the wafer transport robot 10 (in the illustrative example; or more generally, to the control element of the wafer transport device) causing the wafer transport device to immediately stop wafer transport.

[0070] On the other hand, if no wafer transfer problem is detected in operation 70, the process proceeds to operation 74, where it is determined whether wafer transfer is still in progress. If so, the process proceeds to operation 76, which updates the sliding window position (e.g., by incrementing the sliding window sequentially at a temporal interval smaller than the total time width of the sliding window), and then proceeds to operation 62 to analyze the sliding window for the next vibration data. Alternatively, if operation 74 determines that wafer transfer is complete, then... Figure 2 The illustrative chip delivery monitoring method terminates in step 78.

[0071] refer to Figure 3 The diagram illustrates the vibration versus time relationship between normal wafer transport (dashed lines) and problematic wafer transport (solid lines). It is worth noting that... Figure 3 Instead of plotting the measured experimental data, the study graphically depicted some possible general characteristics of vibration data under normal and problematic conditions. Figure 3 The illustration shows that during normal wafer transfer, the operation of the robotic arm 14 engaging and lifting the wafer produces slight vibrations (dashed lines); however, wafer transfer problems in the form of impact events during this operation can produce large-amplitude vibrations, as shown in wafer transfer with wafer transfer problems (solid lines).

[0072] refer to Figure 4 This illustrates a schematic diagram of some further non-limiting illustrative vibration modes that may occur during semiconductor wafer transport problems. (Compared to...) Figure 3 Similarly, it is worth noting that Figure 4 Instead of plotting the measured experimental data, the study graphically depicted some possible characteristics of the vibration data that could indicate certain types of problems in semiconductor wafer delivery. Figure 4 The diagram schematically depicts non-limiting possible vibration modes in the following scenarios: collision of semiconductor wafers during wafer transport (top); scratches forming in the wafer (middle); and tilted insertion of the wafer into slot 20 of FOUP 18 (bottom). A collision produces a large vibration, indicating a sudden impact event. A scratching event produces a smaller amplitude but higher frequency vibration when a scratched component gently drags across the wafer surface. A tilted insertion event produces a high-amplitude initial vibration when the wafer tilts into the slot (or conversely, a well-positioned wafer contacts a tilted, twisted slot), but this vibration dampens rapidly as the wafer enters the slot.

[0073] Figure 3 and Figure 4The examples provided are merely non-limiting illustrative examples of possible types of vibration data that can indicate certain types of problems in wafer transport. Characterizing a specific problem and a specific vibration pattern in semiconductor wafer transport may depend on many factors, such as: the type of vibration sensor; the placement of the vibration sensor 30 on the robot 10 (or other operational connections of the vibration sensor 30 to measure vibration data of elements of the semiconductor wafer transport equipment during wafer transport); the type of semiconductor wafer transport equipment; the size of the wafer being transported; the amount of vibration damping employed by the semiconductor wafer transport equipment; and various combinations thereof and / or the like. To accommodate such implementation-specific problem vibration patterns, the AI-based wafer transport problem detector 40 is appropriately trained on labeled training data generated by the specific implementation to which the detector 40 is intended; or appropriately trained on labeled training data generated by implementations (or multiple implementations) that are sufficiently similar to the implementation to which the detector 40 is intended. In the latter case, a sufficiently similar implementation used to generate training data could, for example, employ semiconductor wafer transport equipment of the same brand and model to transport wafers of the same size and use the same type of vibration sensor mounted in the same position on the robot, as the implementation to which the detector 40 is intended.

[0074] Return to reference Figure 1 and Figure 2 And now further reference Figure 5 This provides more specific, non-restrictive illustrative examples of operations 64 and 70. Figure 5 The context measurement and sliding window extraction operations 60 and 62 are described, and their operation is as previously described for... Figure 2 As described in these operations. Figure 5 In a more specific example, AI-based wafer transport problem detection operation 64 is implemented using three AI-based wafer transport problem detection operations 64-1, 64-2, and 64-3. AI-based wafer transport problem detection operation 64-1 employs an AI algorithm trained to detect wafer transport problems, specifically collisions between the wafer and the rib frame of FOUP 18. AI-based wafer transport problem detection operation 64-2 employs an AI algorithm trained to detect wafer transport problems as wafer scratch events. AI-based wafer transport problem detection operation 64-3 employs an AI algorithm trained to detect tilted insertion into or tilted removal from FOUP 18.

[0075] It should be understood that the illustrative three AI-based chip transport problem detection operations 64-1, 64-2, and 64-3 are examples, and more generally, the number of AI-based chip transport problem detection operations can be two, three, four, or more. Furthermore, in addition to and / or replacing the examples of the illustrative three AI-based chip transport problem detection operations 64-1, 64-2, and 64-3, the AI-based chip transport problem detection operations can be trained to detect different types of problems.

[0076] The three AI-based chip delivery problem detection operations 64-1, 64-2, and 64-3 are each binary classifiers that output a first value (e.g., "1") if a problem is detected, or a second value (e.g., "0") if no problem is detected. Alternatively, it is anticipated that the illustrative multiple binary classifiers 64-1, 64-2, and 64-3 will be replaced with a single multiple-output classifier that has outputs for each type of problem.

[0077] Continue to refer to Figure 5 In this illustrative example, Figure 2 The problem-solving operation 70 is similarly constructed as three constituent decision operations 70-1, 70-2, and 70-3. Decision operation 70-1 determines whether the AI-based wafer transfer problem detection operation 64-1 has detected a collision between the wafer and the rib frame of FOUP 18. Decision operation 70-2 determines whether the AI-based wafer transfer problem detection operation 64-2 has detected a wafer scratch event. Decision operation 70-3 determines whether the AI-based wafer transfer problem detection operation 64-3 has detected a wafer being inserted into or removed from FOUP 18 at an angle.

[0078] Figure 2 The remedial operation of the method 72 in Figure 5 The example is similarly constructed as three remedial actions 72-1, 72-2, and 72-3. Remedial action 72-1 operates in response to a decision that a collision has occurred between the wafer and the rib frame of FOUP 18, and includes stopping wafer delivery and outputting a notification of detection. Immediately stopping wafer delivery is appropriate because continuing delivery during / after the collision is likely to damage the wafer and potentially harm the semiconductor wafer delivery equipment.

[0079] Conversely, remediation 72-2 operates in response to a decision that a wafer scratch event has occurred and includes outputting a notification of wafer scratch detection, but does not include stopping wafer transport. Not immediately stopping wafer transport may be an appropriate remedial action for a wafer scratch event because it is usually less impactful and the scratch event is unlikely to damage the wafer or the semiconductor wafer transport equipment.

[0080] Remedy 72-3 operates in response to a decision that a wafer has been tilted into or removed from FOUP 18, and includes stopping wafer delivery and outputting a notification of detection. Immediately stopping wafer delivery is appropriate because continuing to deliver or remove the wafer during / after tilted insertion is likely to damage the wafer and / or FOUP 18.

[0081] because Figure 5 The method provides information about the type of problem with the wafer transfer (collision, wafer scratch, or tilted insertion / removal), so the notifications included in remedial actions 72-1, 72-2, and 72-3 may optionally include identification of the type of problem detected. Remedial actions 72-1, 72-2, and 72-3 are merely non-limiting illustrative examples, and different types of remediation are contemplated. For example, in a variant embodiment, remediation 72-2 may also include stopping the wafer transfer.

[0082] Below, some further embodiments are described.

[0083] In a non-limiting illustrative embodiment, a semiconductor wafer transfer monitoring device operates in conjunction with an associated semiconductor wafer transfer device. The semiconductor wafer transfer monitoring device includes: a vibration sensor operatively connected to measure vibration data of elements of the associated semiconductor wafer transfer device during semiconductor wafer transfer performed by the associated semiconductor wafer transfer device; and an electronic processor programmed to analyze the measured vibration data to detect problems in the semiconductor wafer transfer and to perform at least one remedial action in response to the detection of a problem. In one embodiment, the at least one remedial action includes stopping the semiconductor wafer transfer performed by the associated semiconductor wafer transfer device. In one embodiment, the at least one remedial action includes outputting a warning indicating the problem. In one embodiment, the electronic processor is programmed to analyze the measured vibration data to detect the problem by inputting the measured vibration data to an artificial intelligence (AI) algorithm trained to detect the problem in the semiconductor wafer transfer. In one embodiment, the electronic processor is programmed to analyze the measured vibration data to detect the problem by comparing the measured vibration data with reference vibration data representing a successful semiconductor wafer transfer. In one embodiment, the vibration sensor is operatively connected to measure vibration data of a wafer transfer robot of the associated semiconductor wafer transfer equipment. In one embodiment, the vibration sensor is disposed on the wafer transfer robot and includes a wireless transmitter or transceiver for wirelessly transmitting the measured vibration data to the electronic processor. In one embodiment, the vibration sensor includes an accelerometer. In one embodiment, the electronic processor is programmed to analyze the vibration data to detect problems in semiconductor wafer transfer, including collisions of the semiconductor wafers transferred by the semiconductor wafer transfer device. In one embodiment, the electronic processor is programmed to analyze the vibration data to detect the formation of at least one scratch on the semiconductor wafers transferred by the semiconductor wafer transfer device. In one embodiment, the electronic processor is programmed to analyze the vibration data to detect tilting insertions or removals of semiconductor wafers transferred by the semiconductor wafer transfer device to or from a wafer storage tank. In one embodiment, the electronic processor is further programmed to: receive control data related to the semiconductor wafer transfer; determine from the control data the stage of the semiconductor wafer transfer at the time of the problem; and classify the problem of the semiconductor wafer transfer at least in part based on the stage of the semiconductor wafer transfer at the time of the problem.In one embodiment, the electronic processor is programmed to receive control data related to the semiconductor wafer transfer from the associated semiconductor wafer transfer device.

[0084] In a non-limiting illustrative embodiment, a semiconductor wafer transport monitoring method includes: measuring vibrations of an element during the transport of a semiconductor wafer; analyzing the measured vibrations to detect collisions or scratches on the semiconductor wafer during transport; and performing at least one remedial action in response to the detection of a collision or scratch on the semiconductor wafer. In one embodiment, the analysis includes inputting the measured vibrations into an artificial intelligence (AI) algorithm trained to detect the collisions or scratches on the semiconductor wafer. In one embodiment, the vibrations of the element are measured using an accelerometer. In one embodiment, the semiconductor wafer transport monitoring method also includes: performing the transport of the semiconductor wafer using a wafer transport robot; wherein the measurement includes measuring the vibrations of the wafer transport robot. In one embodiment, the semiconductor wafer transport monitoring method also includes: determining the stage of the transport of the semiconductor wafer at the time of the detection of the collision or scratch; and classifying the collision or scratch on the semiconductor wafer at least in part based on the stage of the transport of the semiconductor wafer at the time of the detection of the collision or scratch.

[0085] In a non-limiting illustrative embodiment, the semiconductor wafer transfer apparatus includes: a wafer transfer robot configured to transfer a semiconductor wafer between a wafer carrier and a semiconductor wafer handling or characterization tool; a vibration sensor for measuring vibrations of the wafer transfer robot; and an electronic processor programmed to detect problems in the transfer of the semiconductor wafer performed by the wafer transfer robot by analyzing the vibrations of the wafer transfer robot measured by the vibration sensor during transfer. In one embodiment, the vibration sensor is disposed on the wafer transfer robot and includes: a wireless transceiver or transmitter for transmitting the measurement of the vibrations of the wafer transfer robot from the vibration sensor to the electronic processor.

[0086] In a non-limiting illustrative embodiment, semiconductor wafer transport monitoring includes measuring vibrations of the component during semiconductor wafer transport. The measured vibrations are analyzed to detect collisions or scratches on the semiconductor wafer during transport. At least one remedial action is performed in response to the detection of a collision or scratch on the semiconductor wafer, such as outputting a notification of a collision or scratch or stopping the transport of the semiconductor wafer. The component measuring the vibrations may be a wafer transport robot used during transport. The analysis of the measured vibrations may include inputting the measured vibrations into an artificial intelligence (AI) algorithm trained to detect collisions or scratches on the semiconductor wafer.

[0087] The foregoing has outlined features of several embodiments to enable those skilled in the art to better understand various aspects of this disclosure. Those skilled in the art should understand that they can readily use this disclosure as a basis for designing or modifying other processes and structures for performing the same purposes and / or achieving the same advantages of the embodiments described herein. Those skilled in the art should also recognize that such equivalent structures do not depart from the spirit and scope of this disclosure, and that various alterations, substitutions, and changes can be made to this document without departing from the spirit and scope of this disclosure.

Claims

1. A semiconductor wafer transport monitoring device that operates in conjunction with related semiconductor wafer transport equipment, characterized in that, The semiconductor wafer transport monitoring device includes: A vibration sensor, operatively connected to measure measured vibration data of components of the associated semiconductor wafer transport equipment during semiconductor wafer transport; and An electronic processor is programmed to analyze the measured vibration data to detect problems in the semiconductor wafer delivery and to perform at least one remedial action in response to the detection of the problems in the semiconductor wafer delivery.

2. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The at least one remedial action includes stopping the semiconductor wafer transfer or output of a warning indicating the problem performed by the associated semiconductor wafer transfer equipment.

3. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The electronic processor is programmed to analyze the measured vibration data to detect the problem in the semiconductor wafer delivery by inputting the measured vibration data into an artificial intelligence algorithm trained to detect the problem.

4. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The electronic processor is programmed to analyze the measured vibration data to detect the problem in the semiconductor wafer delivery by comparing the measured vibration data with reference vibration data representing a successful semiconductor wafer delivery.

5. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The vibration sensor is operatively connected to measure vibration data of the wafer transfer robot of the associated semiconductor wafer transfer equipment.

6. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The electronic processor is programmed to analyze the vibration data to detect problems in the semiconductor wafer transport, including collisions of the semiconductor wafer transported by the semiconductor wafer transporter, formation of at least one scratch on the semiconductor wafer transported by the semiconductor wafer transporter, or tilting insertion or removal of the semiconductor wafer transported by the semiconductor wafer transporter to or from the wafer storage tank.

7. The semiconductor wafer transfer monitoring device according to claim 1, characterized in that, The electronic processor is further programmed to: Receive control data related to the transmission of the semiconductor wafer; The stage of semiconductor wafer delivery at the moment of the problem in the semiconductor wafer delivery is determined from the control data; as well as The problems with semiconductor wafer transport are classified at least in part based on the stage of semiconductor wafer transport at the time of the problems.

8. The semiconductor wafer transport monitoring device according to claim 7, characterized in that, The electronic processor is programmed to receive control data related to the semiconductor wafer transfer from the associated semiconductor wafer transfer device.

9. A semiconductor wafer transfer monitoring device, characterized in that, include: A wafer transfer robot is used to transfer semiconductor wafers between a wafer carrier and semiconductor wafer processing or characterization tools. Vibration sensor, used to measure the vibration of the chip delivery robot; as well as An electronic processor is programmed to detect problems in semiconductor wafer transfer performed by the wafer transfer robot by analyzing vibrations measured by the vibration sensor during transfer.

10. The semiconductor wafer transport monitoring device according to claim 9, characterized in that, The vibration sensor is mounted on the wafer transfer robot and the vibration sensor includes: A wireless transceiver or transmitter is used to transmit the measurement of the vibration of the wafer-transfer robot from the vibration sensor to the electronic processor.

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