System and method for processing wafers

Abstract

The present disclosure provides a system and method for processing wafers. The system and method include detecting vibrations of a wafer transfer robot, generating signals based on the vibrations, and processing the signals for determining a condition of the wafers held by the wafer transfer robot.

Description

Technical Field

[0001] The present disclosure relates to systems and methods for processing wafers. Background Art

[0002] Integrated circuit (IC) manufacturing utilizes various processing steps including etching and depositing films (i.e., layers) on masking wafers to create trenches, vias, metal wiring, components such as capacitors, resistors, inductors, transistors, antennas, and generally insulating and conductive structures for passive and active circuits during the production of integrated circuits on batches of wafers formed from semiconductor substrate materials.

[0003] Typically, the processing steps are performed in a linear assembly line manner via an automated or at least semi-automated system. The processing steps may include cleaning, etching, rinsing, and / or depositing materials on the wafer in a chamber or separate tank of solution. Wafers can be moved into and out of processing solutions contained in different tanks, thereby requiring the wafers to be placed on a tank transporter or mechanism, and the wafers to be removed from the tank transporter or mechanism, as well as the wafers to be moved between different tank transporters. That is, the wafers can be automatically moved, transported, and / or transferred multiple times during wafer processing, which typically involves exposure of the wafer to high / low temperatures, temperature changes, high / low pressures, pressure changes, and different chemical reagents. Thus, the wafers may be subjected to stress and even strain during the processing of the wafers, as well as during the transportation / transfer of the wafers that are being processed. Summary of the invention

[0004] In one embodiment, a system includes a wafer elevator, a wafer transfer robot, a vibration sensor attached to the wafer transfer robot, and a processing module communicatively coupled to the vibration sensor. The wafer elevator is used to move at least one wafer into a chemical bath for performing a processing step on the at least one wafer and remove at least one wafer from the chemical bath. The wafer transfer robot is used to hold at least one wafer, place at least one wafer on the wafer elevator, and remove at least one wafer from the wafer elevator. The vibration sensor is used to detect vibration of the wafer transfer robot during holding or removing at least one wafer by the wafer transfer robot and generate a signal based on the vibration. The processing module is used to process the signal for determining a condition of at least one wafer.

[0005] In another embodiment, a system for use with a semiconductor workbench is provided. The semiconductor workbench includes at least one semiconductor processing tank and at least one wafer elevator. Each semiconductor processing tank contains a chemical bath, and each wafer elevator is configured to move wafers into and out of the chemical bath of the corresponding semiconductor processing tank. The system includes a wafer transfer robot that is used to hold at least one wafer, place at least one wafer on the wafer elevator, and remove at least one wafer from the wafer elevator. The system also includes a vibration sensor that is attached to the wafer transfer robot and is used to detect vibrations of the wafer transfer robot after the wafer transfer robot removes at least one wafer from the wafer elevator, generate a signal based on the vibration, and send the signal to a processing module for determining a condition of at least one wafer held by the wafer transfer robot after removal from the wafer elevator.

[0006] In yet another embodiment, a method for determining a condition of a wafer during processing of the wafer by a wafer processing system is provided. The method includes processing one or more of the wafers in a processing tank, removing the one or more wafers from the processing tank using a wafer elevator, receiving the one or more wafers at a wafer transfer robot, detecting vibrations of the wafer transfer robot, generating a signal based on the vibrations, and processing the signal for determining a condition of the one or more wafers held by the wafer transfer robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] When accompanied by Figure 1 The aspects of the present disclosure are better understood from the following detailed description when read together. It should be noted that, in accordance with standard practice in the industry, various features are not depicted to scale. In fact, the dimensions of various features may be arbitrarily increased or reduced for clarity of discussion.

[0008] Figure 1 A system for determining a condition of a wafer during processing of the wafer according to an embodiment of the present disclosure is illustrated;

[0009] Figure 2A An example of an embodiment of the present disclosure is close to Figure 1 The bottom part of the wafer elevator Figure 1 an end view of an arm of a wafer transfer robot;

[0010] Figure 2B Another embodiment according to the present disclosure is illustrated close to Figure 1 The bottom part of the wafer elevator Figure 1 an end view of an arm of a wafer transfer robot;

[0011] Figure 3A An example of an embodiment of the present disclosure is as follows Figure 1A time series of vibrations of a wafer transfer robot illustrated on a monitor;

[0012] Figure 3B An example of a broken wafer being grasped by a wafer transfer robot according to an embodiment of the present disclosure is shown in FIG. Figure 1 A time series of vibrations of a wafer transfer robot illustrated on a monitor;

[0013] Figure 3C An example of a wafer being missed from a wafer transfer robot according to an embodiment of the present disclosure is shown. Figure 1 a time series of vibrations of a wafer transfer robot illustrated on a monitor of; and

[0014] Figure 4 The present invention is a flowchart of a method for determining a condition of a wafer during processing of the wafer according to one embodiment of the present disclosure.

[0015]

Explanation of symbols

[0016] 100: System

[0017] 102: Robot

[0018] 104: Vibration sensor

[0019] 106: Elevator

[0020] 108: Processing Area / Tank

[0021] 110: Processing module

[0022] 112: Monitor

[0023] 114: Optical sensor

[0024] 116: Wafer counting sensor

[0025] 118:Chemical Bath

[0026] 120: Wafer

[0027] 121: Arm

[0028] 122: Bottom part

[0029] 124: Slot

[0030] 126: Side part

[0031] 128: Vertical direction

[0032] 130: Horizontal direction

[0033] 132: Wired connection

[0034] 134: Wired connection

[0035] 136: Wired connection

[0036] 202: Slot

[0037] 204: Edge

[0038] 206: generally horizontal outward

[0039] 208: generally horizontal inward

[0040] 400:Method

[0041] 402~408: Steps DETAILED DESCRIPTION

[0042] The embodiments disclosed below provide many different embodiments or examples for implementing the different features of the provided themes. The specific examples of components and configurations are described below to simplify the disclosure. Of course, these are only examples and are not intended to be limiting. For example, the formation of a first feature above or on a second feature in the following description may include an embodiment in which the first feature and the second feature are formed in direct contact, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature so that the first feature and the second feature may not be in direct contact. In addition, the disclosure may repeat component symbols and / or letters in various examples. This repetition is for the purpose of simplicity and clarity and does not substantially specify the relationship between the various embodiments and / or configurations discussed.

[0043] Additionally, spatially relative terms, such as "below," "beneath," "lower," "above," "upper," "vertical," "horizontal," etc., may be used herein for ease of description to describe the relationship of one element or feature to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may be interpreted accordingly.

[0044] Wafers may experience forces such as stresses, and relative molecular movements such as strains during IC manufacturing steps. For example, forces and resulting strains may be caused by exposure of the wafer to chemical processes such as chemical baths, electrical currents, high / low pressure, pressure changes, high / low temperature, temperature changes, ion bombardment, doping, oxidation, metallization, and other manufacturing processes. Many manufacturing processes may be automated or semi-automated by mechanical systems or devices, including robots or other automated devices, which may subject the wafer to added stresses and strains caused by handling, transfer, and / or transportation of the wafer.

[0045] Wafers may suffer physical damage, such as cracking or breaking, during or between different processing steps. Additionally, wafers may become improperly positioned in an automated device while being transferred from one device to another, or due to transporting wafers in an automated device as the device moves wafers from one location in a processing assembly to another location in a processing assembly. Additionally, wafers may be missed from automated devices used to grab batches of wafers, transport wafers, and / or transfer wafers to other devices.

[0046] For example, when a wet bench is used to perform a wet etching process step on wafers, a first mechanized automation subsystem of the wet bench may move batches of wafers into and out of different chemical solutions (also referred to as chemical baths), and a second mechanized automation subsystem may transport the batches of wafers to a location near a component of the first subsystem and then transfer the batches of wafers to the component of the first subsystem and collect the wafers from the component of the first subsystem. Wafers may be damaged while in the chemical bath, while being placed in or removed from the chemical bath, during transfer of wafers between the first automation subsystem and the second automation subsystem, and / or during transportation of wafers through the first automation subsystem and / or the second automation subsystem. The chemical baths are typically held in a processing tank or chamber. If one or more wafers are physically damaged, or are improperly held or positioned within an automation system due to poor transfer between automation systems, the wafers may fall off (i.e., be missed) from the automation system. For example, a damaged or misoriented wafer held by a component of an automation system may fall into or remain in a processing tank.

[0047] It would be advantageous to determine the condition of wafers while they are being processed by a wafer handling system, such as determining whether one or more wafers have been damaged and / or improperly positioned within, or missing from, components of a system designed to transfer / transport wafers during processing so that processing can be stopped to avoid contamination and / or damage to other wafers being processed by the system, and / or to avoid damage to components of the automation system itself.

[0048] Figure 1A system 100 for determining conditions of wafers during processing of wafers according to an embodiment of the present disclosure is illustrated. The system 100 includes a wafer transfer robot 102 and one or more vibration sensors 104. The system 100 may optionally include at least one of one or more wafer elevators 106, one or more processing areas 108, a processing module 110, a monitor 112, one or more optical sensors 114, and one or more wafer counting sensors 116. The processing area 108 may be defined by an enclosure such as a processing vessel (e.g., a processing tank or a processing chamber), or any other area in which one or more processing procedures are performed on wafers. The processing area may be any area in which one or more processing parameters such as temperature, pressure, type, and concentration of a processing agent may be controlled. In one embodiment, the processing area may contain a chemical bath. In other embodiments, the processing vessel includes a processing tank and a processing chamber of a deposition system such as a chemical vapor deposition (CVD) and a physical vapor deposition (PVD) system. For purposes of the following discussion, the one or more processing regions are one or more processing tanks (108), but the scope of the present disclosure encompasses any type of processing region or processing vessel. Each processing tank 108 may contain one or more wafer treating agents forming a chemical bath 118. The treating agents may include any solution used in the processing of wafers, including ionized water for rinsing. In one embodiment, the chemical bath may be used in an IC manufacturing process performed on semiconductor wafers, such as wet etching, rinsing, or chemical deposition of materials on the wafer. However, the scope of the present disclosure includes all types of processing processes performed on semiconductor wafers, including processes performed on wafers formed of insulators and / or metals.

[0049] In one embodiment, any combination of the wafer transfer robot 102, one or more wafer elevators 106, one or more processing tanks 108, processing modules 110, monitors 112, and optical sensors 114 may be components of a wafer processing system, such as a semiconductor processing station. For example, wet stations are used to etch semiconductor wafers in different chemical solutions also known as chemical baths, and other manufacturing stations are used to perform other processing procedures for manufacturing semiconductor dies including integrated circuits from semiconductor wafers.

[0050] The wafer transfer robot 102 is used to hold one or more wafers 120, including a batch of wafers (not shown). The wafer transfer robot 102 is also used to place the wafer 120 on the wafer elevator 106, remove the wafer 120 from the wafer elevator 106, and transport the wafer 120 from a position near a wafer elevator (e.g., the wafer elevator 106) to a position near another wafer elevator (not shown) for placing the wafer 120 on the other wafer elevator and then removing the wafer 120 from the other wafer elevator. In one embodiment, the wafer transfer robot 102 includes two arms 121 assembled to hold the wafer 120. The two arms 121 can be positioned directly opposite to each other.

[0051] The wafer elevator 106 is used to move the wafer 120 received from the wafer transfer robot 102 into the chemical bath 118, and usually remove the wafer 120 from the chemical bath 118 after a given processing time. In one embodiment, the wafer elevator 106 is used to lower into the chemical bath 118 and rise from the chemical bath for immersing the wafer 120 in the chemical bath 118 and removing the wafer 120 from the chemical bath 118. In one embodiment, the wafer elevator 106 is used to move generally vertically downward for lowering into the chemical bath 118 and generally vertically upward for rising from the chemical bath 118. In one embodiment, the wafer elevator 106 has a bottom portion 122 with an internal slot 124. For example, the bottom portion 122 can be a metal, ceramic or plastic sheet. The size, depth and spacing of the slot 124 are configured so that a single slot can receive a portion of the edge of a single wafer for temporarily properly holding the wafer on the wafer elevator 106. The wafer elevator 106 may also include side portions 126 for engaging a vertical transfer member for moving the wafer elevator in a generally vertical direction 128. Vertical transfer members are well known in the art of wafer fabrication and may include a robotic arm or other type of powered device having a component that moves generally vertically.

[0052] In one embodiment, the wafer transfer robot 102 is configured to move in any direction. Although not shown, the wafer transfer robot 102 may be attached to a robotic arm or other mechanical system for moving the wafer transfer robot in any direction. For example, the processing module 110 or other external computer or control module (not shown) may execute pre-programmed code for directing the movement of the wafer transfer robot 102 and other components such as the wafer elevator 106 during processing of the wafer 120 in various chemical baths used, for example, to complete a processing manufacturing cycle.

[0053] In one embodiment, the wafer transfer robot 102 is configured to move in a generally horizontal direction 130 and in a generally vertical direction 128. For example, and as illustrated, the wafer transfer robot 102 holding the wafer 120 is positioned at a location adjacent to the wafer elevator 106. The wafer transfer robot 102 may then move in a generally vertical downward direction for placement adjacent to the wafer elevator 106, or for placement circumferentially surrounding the wafer elevator 106.

[0054] Figure 2A and Figure 2B Schematic diagram illustrating an end view of an arm 121 of a wafer transfer robot 102 proximate to a bottom portion 122 of a wafer elevator 106 according to an embodiment of the present disclosure. In one embodiment, at least one arm 121 of the wafer transfer robot 102 is movable in a substantially horizontal direction, however the scope of the present disclosure encompasses a wafer transfer robot 102 including two movable arms 121. At least one arm 121, or alternatively both arms 121, are configured to have a plurality of slots 202 (also referred to as grooves) for receiving a portion of an edge 204 of a wafer 120 for properly holding the wafer 120 on the wafer transfer robot 102.

[0055] If through Figure 2A As illustrated, the wafer transfer robot 102 has previously moved in a generally vertical downward direction for placement of the arms 121 adjacent to the wafer elevator 106. Once positioned adjacent to the wafer elevator 106, one or both of the arms 121 of the wafer transfer robot 102 move generally horizontally outward 206 (i.e., away from each other) to thereby enable the wafer 120 to be indexed or lowered from the wafer transfer robot 102 into position on the bottom portion 122 of the wafer elevator 106. In one embodiment, a portion of the edge 204 of the wafer 120 is lowered into a slot 124 ( Figure 1 Each slot 124 is configured to receive a portion of an edge 204 of a corresponding wafer such that the corresponding wafer is secured in an upright position on the bottom portion 122 of the wafer elevator 106 .

[0056] Once the wafer elevator 106 has received the wafer 120 from the wafer transfer robot 102, the wafer elevator 106 may be lowered in a generally vertical downward direction for immersing the wafer 120 in the chemical bath 118. After a predetermined processing time, the wafer elevator 106 may be raised in a generally vertical upward direction for repositioning the wafer elevator 106 in a position adjacent to the wafer transfer robot 102.

[0057] Once the wafer elevator 106 is repositioned adjacent to the wafer transfer robot 102, such as by Figure 2BAs illustrated, one or both of the arms 121 of the wafer transfer robot 102 move generally horizontally inward 208 (i.e., toward each other) for collecting (i.e., removing) wafers 120 from the wafer elevator 106. In one embodiment, as one or both of the arms 121 move generally horizontally inward 208, the slots 202 in the arms 121 of the wafer transfer robot 102 engage portions of the edges 204 of the wafers 120. In one embodiment, the slots 202 in the arms 121 are designed so that as the arms 121 engage portions of the edges 204 of the wafers 120, the wafers 120 are lifted vertically upward a small distance, thereby disengaging each wafer 120 from its corresponding slot 124 in the bottom portion 122 of the wafer elevator 106. In another embodiment, the wafer 120 is disengaged from the slot 124 in the bottom portion 122 of the wafer elevator 106 as the wafer transfer robot 102 moves away from the wafer elevator 106 in a generally vertical upward direction.

[0058] Once the wafer transfer robot 102 has moved a sufficient vertical upward distance (e.g., a sufficient distance to clean all of the elevators 106 and other components that may be attached to the processing tank 108), the wafer transfer robot 102 can be moved in a substantially horizontal direction 130 for placement in a position adjacent to another wafer elevator corresponding to another processing tank for performing the next processing procedure on the wafer 120 of the wafer transfer robot 102.

[0059] When wafers are processed with liquids, gases, or solids including known semiconductor processes, these wafers may be subjected to stresses and resulting strains caused by exposure to high / low temperatures, rapid temperature changes, high / low pressure, rapid pressure changes, various chemical compounds, and / or vibrations. Vibrations may be intentionally induced, for example, by vibration of a chemical bath as part of a processing step, or by transfer of wafers from one mechanical transport / transfer system to another mechanical transport / transfer system. For example, the wafers 120 may be subjected to stresses / strains that occur when the wafers 120 are transported into and out of the chemical baths 118 by the wafer elevator 106, and by transfer of the wafers 120 from the wafer transport robot 102 to the wafer elevator 106 and / or by collection of the wafers 120 from the wafer elevator 106 by the wafer transfer robot 102. These stresses / strains, alone or in any combination, may change the condition of one or more of the wafers 120, such as causing the wafers 120 to crack or break. If the wafer breaks into one or more parts, some of the parts may fall from the wafer transfer robot 102 into the chemical bath 118, or all of the parts may fall from the wafer transfer robot 102, resulting in one or more missing wafers for the wafer transfer robot 102. In addition, cracked or broken wafers, and in some cases, uncracked, unbroken wafers (i.e., intact wafers) may not be properly retained by the wafer transport robot 102 when collected from the wafer elevator 106 by the wafer transfer robot 102.

[0060] For example, when a portion of the edge 204 of the wafer 120 to be engaged by the slot 202 of the wafer transfer robot 102 when collecting the wafer 120 from the wafer elevator 106 is not received by the slot 202 or any slot, or is received by an incorrect slot, the wafer may be incorrectly held by the wafer transfer robot 102. An incorrect slot is a slot that has received a portion of the edge 204 of two or more wafers, for example, or a slot on one arm 121 of the wafer transfer robot 102 that receives a portion of the edge 204 of a wafer that is directly but not directly opposite to a slot on another opposite arm that has received a portion of the opposite edge of the wafer.

[0061] These wafer conditions, such as cracked, broken, improperly held wafers, or missing wafers, may affect the subsequent processing of wafers held by the wafer transfer robot 102 when these wafers are transferred to other wafer elevators for subsequent processing, or may affect the subsequent processing of new batches of wafers due to the presence of wafers or portions of wafers that have been dropped or held in the chemical bath 118.

[0062] According to embodiments described herein, one or more vibration sensors 104 are attached to the wafer transfer robot 102. In one embodiment, the vibration sensor 104 is attached to one arm 121 of the wafer transfer robot 102, or alternatively, one vibration sensor 104 is attached to each arm 121 of the wafer transfer robot 102.

[0063] The vibration sensor 104 is used to detect vibrations of the wafer transfer robot 102. Although the vibration sensor 104 may detect vibrations of the wafer transfer robot 102 at any time during operation of the wafer transfer robot 102, vibrations detected after the wafer transfer robot 102 removes (i.e., collects) the wafer 120 from the wafer elevator 106 may be of particular interest. In one embodiment, the vibration sensor 104 is an inertial-based motion detector for detecting motion such as vibratory motion. In some embodiments, the vibration sensor 104 includes an accelerometer, a gyroscope component, one or more other suitable components, or a combination thereof.

[0064] According to one embodiment of the present disclosure, the vibration sensor 104 detects vibration of the wafer transfer robot 102 and generates a signal based on the detected vibration. The scope of the present disclosure includes vibration sensors that include a microprocessor or CPU that processes the detected vibration to generate an electrical signal such as a current, voltage, or magnetic signal, and other vibration sensors that may not include a processor but may include components formed of materials such as piezoelectric materials that generate electrical signals from their vibration motion.

[0065] The processing module 110 may include one or more processors, CPUs, microcontrollers, memories, ADC / DAC units, and associated logic circuit diagrams and / or firmware for digital and / or analog signal processing. In one embodiment, the processing module 110 is used to receive signals from the vibration sensor 104 and process the signals. For example, the processing module 110 may process the signals for display as a time series or spectrum on the monitor 112. The processing module 110 may alternatively, or in addition to displaying the processed signals, compare the processed signals or the patterns of the processed signals in the frequency domain and / or time domain with the signals or patterns of signals stored in the memory. Each signal or signal pattern stored in the memory may be associated with a corresponding cause of the signal also stored in the memory.

[0066] For example, Figure 3AA time series of vibrations of the wafer transfer robot 102 as illustrated on the monitor 112 according to an embodiment of the present disclosure is illustrated. From t=0 to t=t1, the wafer transfer robot 102 is moving to be positioned for collecting a wafer 120 from the wafer elevator 106, at t=t1, the wafer transfer robot 102 collects the wafer 120 from the wafer elevator 106, and for times greater than t=t1, the wafer transfer robot 102 is moving away from the wafer elevator 106. The spike in the vibration at t=t1 indicates the collection (i.e., removal) of the wafer 120 from the wafer elevator 106, and the smaller vibrations occurring for times greater than t=t1 indicate the damping of the initial vibration caused by the collection event at t=t1. Figure 3A There is no indication that any of the wafers are broken, cracked, missing, or improperly held by the wafer transfer robot 102 .

[0067] Figure 3B A time series of vibrations of the wafer transfer robot 102 as illustrated on the monitor 112 depicting a broken wafer being held by the wafer transfer robot 102 according to an embodiment of the present disclosure is illustrated. The collection event is indicated by a spike in the vibration at t=t1, however, the pattern of spikes at times t>t1 indicates a break in the wafer being held by the wafer transfer robot 102.

[0068] Figure 3C A time series of vibrations of the wafer transfer robot 102 as illustrated on the monitor 112 depicting wafers being missed from the wafer transfer robot 102 according to an embodiment of the present disclosure is illustrated. The collection event is indicated by a spike in the vibration at t=t1, however, the pattern of spikes at t>t1 indicates that wafers are being missed from the wafer transfer robot 102 after the wafer transfer robot 102 has collected the wafer 120 from the wafer elevator 106. Thus, the missed wafer, or at least a portion of the missed wafer, may be in the chemical bath 118 of the processing tank 108 corresponding to the wafer elevator 106.

[0069] Although the processing module 110 may process the signals received from the vibration sensor 104 for display as a time series, the processing module 110 may generate a spectrum of the time series and analyze the spectrum or a combination of the spectrum and the time series. In other embodiments, the processing module 110 may analyze the processed signals in conjunction with signals or signal patterns stored in a memory of the processing module 110 to determine the condition of the wafer being processed and / or being held by the wafer transfer robot 102.

[0070] Reference Figure 1 , the vibration sensor 104 may be communicatively coupled to the processing module 110 via the wired connection 132. However, the scope of the present disclosure includes wireless communication between the vibration sensor 104 and the processing module 110.

[0071] The monitor 112 may be communicatively coupled to the processing module 110 via a wired connection 134 or wirelessly. In one embodiment, when the processing module 110 determines that the condition of the wafers 120 being held by the wafer transfer robot 102 includes at least one of a wafer being cracked, broken, improperly held, and / or missing, the processing module 110 generates an alarm signal for display on the monitor 112. The alarm signal alerts an operator, thereby allowing the operator to pause the current manufacturing process step so that missing wafers can be removed from the processing tank, broken and / or cracked wafers can be removed from the wafer transfer robot 102, and improperly held wafers can be adjusted so that these improperly held wafers are properly held by the wafer transfer robot 102. In addition, the operator may decide to discard all wafers currently being processed and start a new processing cycle with new wafers based on the alarm signal and the type of wafer condition(s) determined by the processing module 110 and / or after checking one or more processing tanks for missing wafers.

[0072] One or more optical sensors 114 may be communicatively coupled to the processing module 110 via a wired connection 136 or wirelessly. The optical sensor 114 may be positioned to capture an image of at least one of the chemical baths contained within the one or more processing tanks. In another embodiment, the optical sensor 114 may be used to capture additional images of the wafer elevator 106 and / or the wafer transfer robot 102. In one embodiment, the optical sensor 114 is a charge coupled device. The processing module 110 is used to process the captured images and / or send the captured images to the monitor 112 for display.

[0073] The optical sensor 114 may be used by an operator of the system 100 in conjunction with analysis of the vibrations of the wafer transfer robot 102 to determine the condition of the wafer 120 being held by the wafer transfer robot 102. For example, the optical sensor 114 has limited resolution, and captured images of the inside of a processing tank that may not be adequately illuminated may be difficult to interpret. In addition, some chemical baths contain compounds that may be opaque or partially transparent to light, and / or the opacity of some chemical baths may change during processing of the wafer. Furthermore, imaging of the chemical bath may also be hindered by reflections of imaging light from the surface of the chemical bath. Additionally, the surface of the bath may have ripples, thereby adding difficulty to imaging items such as wafers or portions of wafers that may be submerged in the bath.

[0074] Although optical imaging methods for determining the condition of a wafer or a system for processing a wafer may not always be sufficient and accurate, in accordance with disclosed embodiments, captured images of a bath contained in a processing tank may be used in conjunction with detected vibrations of the wafer transfer robot 102. For example, results from the optical imaging sensor 114 may be used to aid training by correlating wafer conditions, such as broken, cracked, missing, and / or improperly held wafers as determined by analysis of detected vibrations and verified by captured images, with corresponding vibration signals for creating a table of vibration signals or patterns of vibration signals in time space or frequency space with corresponding wafer conditions. The table may be stored in a memory of the processing module 110 or in a memory external to the processing module 110. In another embodiment, when the vibration signal alone is not a determining factor in the condition (i.e., state) of the wafer 120, the captured image may be used in conjunction with the vibration signal to determine the condition of the wafer 120 on the wafer transfer robot 102.

[0075] One or more wafer counting sensors 116 may be used to detect the number of wafers held by the wafer transfer robot 102 and generate corresponding wafer counting signals. In one embodiment, the wafer counting sensor 116 is attached to the wafer transfer robot 102, such as one or two arms 121 of the wafer transfer robot 102. The wafer counting sensor 116 may include one or more pressure sensors, mechanical sensors, and / or electromechanical sensors for detecting the presence of wafers in corresponding slots of the arm 121 and generating corresponding wafer counting signals. The wafer counting sensor 116 may be communicatively coupled to the processing module 110 via a wired connection or a wireless connection. The processing module 110 is further used to receive the wafer counting signal from each wafer counting sensor 116 and process the wafer counting signal(s) for determining the number of wafers being held by the wafer transfer robot 102. The processing module 110 and the monitor 112 may be used to display the determined number of wafers on the monitor 112, and / or use the determined number of wafers in combination with analysis of vibrations of the wafer transfer robot 102 and / or captured images to determine conditions of the wafers 120 held by the wafer transfer robot 102, and / or to create a table of vibration signals or patterns of vibration signals in time space or frequency space having corresponding wafer conditions.

[0076] According to one embodiment of the present disclosure, the wafer counting sensor 116 includes a plurality of wafer sensors, and at least one slot 202 on the arm 121 of the wafer transfer robot 102 includes a wafer sensor for detecting whether the slot 202 contains (i.e., engages with) a portion of the edge 204 of a respective wafer. In one embodiment, a wafer sensor is attached to a portion of each slot 202 on the arm 121 of the wafer transfer robot 102. The electromechanical sensor may include a piezoelectric material that generates a counting signal when the piezoelectric material is stressed by the force of the wafer against the sensor, thereby causing strain in the piezoelectric material that results in the generation of a counting signal.

[0077] Figure 4 Flowchart of a method 400 for determining a condition of a wafer during processing of the wafer according to an embodiment of the present disclosure. The wafers may be processed by any known semiconductor processing system including a semiconductor processing station. The station is configured to perform one or more processing procedures on batches of semiconductor wafers. For example, the processing procedures may include, but are not limited to, wet etching, rinsing, and / or cleaning. However, the scope of the present disclosure encompasses any type of wafer processing procedures that involve mechanical transfer of wafers to and from a processing chamber or processing tank and / or mechanical transfer of wafers between wafer transport / transfer systems and devices.

[0078] The workbench may include at least one processing area, such as a processing tank, and a corresponding wafer elevator. For the purpose of the following discussion, one or more processing areas are one or more processing tanks, but the scope of the present disclosure covers any type of processing area or processing container. Each processing tank is used to perform one or more processing steps, also known as processing procedures, on one or more wafers. For example, the processing tank may contain a chemical bath or other fluid agent used to perform a specific processing step or procedure. Each wafer elevator is configured to move wafers into and out of the corresponding processing tank. In one embodiment, the wafer elevator moves the wafer in a substantially vertical direction. The system further includes a wafer transfer robot and a vibration sensor, which is attached to the wafer transfer robot. The wafer transfer robot is configured to hold wafers, transfer wafers to at least one wafer elevator, and remove wafers from at least one wafer elevator. According to one embodiment, the wafer transfer robot is used to move wafers from one wafer elevator to another wafer elevator. In one embodiment, the wafer transfer robot is configured to move in a substantially vertical direction for placing wafers on the wafer transfer elevator and / or removing wafers from the wafer transfer elevator, and to move in a substantially horizontal direction for moving wafers from a position near a first wafer transfer elevator to a position near a second wafer transfer elevator. The wafer transfer robot may then move in a substantially vertical direction for placing wafers on the second wafer transfer elevator and / or removing wafers from the second wafer transfer elevator.

[0079] In step 402 of the method, vibrations of the wafer transfer robot 102 are detected. In one embodiment, one or more vibration sensors 104 detect vibrations of the wafer transfer robot 102. According to another embodiment, the wafer transfer robot 102 includes at least two arms 121 configured to hold a wafer 120, place a wafer on a wafer elevator 106, and remove a wafer from the wafer elevator 106. At least one arm is movable relative to another arm for placing a wafer on the wafer elevator 106 and removing a wafer from the wafer elevator 106. In one embodiment, at least one vibration sensor 104 is attached to at least one arm 121 of the wafer transfer robot 102.

[0080] In step 404, a signal is generated based on the vibration. In one embodiment, the vibration sensor 104 is used to generate a signal based on the detected vibration of the wafer transfer robot 102. The signal can be an electrical signal, such as a current, voltage, magnetic, or electromagnetic signal. The signal can be an analog or digital signal, either of which can represent, for example, an analog or digital time series of the detected vibration or an analog or digital frequency spectrum of the detected vibration. In one embodiment, the vibration sensor 104 is an electromechanical sensor, which can include, for example, a gyroscopic component, a piezoelectric component, and / or an accelerometer component.

[0081] In step 406, the signals are processed for use in determining the condition of the wafer 120 held by the wafer transfer robot 102. In one embodiment, the signals are processed by a processing module 110 that includes, for example, a microprocessor, a CPU, a microcontroller, a memory, an analog / digital converter, and digital logic and processing circuitry. Although the scope of the present disclosure encompasses detecting vibrations, generating signals, and processing signals at any and all times during operation of the wafer transfer robot 102 and / or system components used to process the wafer 120, according to one embodiment, the signals are processed for use in determining the condition of the wafer 120 held by the wafer transfer robot 102 directly after the wafer 120 is removed from the wafer elevator 106 by the wafer transfer robot 102. According to another embodiment of the present disclosure, a signal is processed during a time period including the wafer 120 being removed from the first wafer elevator by the wafer transfer robot 102, the wafer transfer robot 102 moving to a position near the second wafer elevator, and the wafer 120 being placed on the second wafer elevator by the wafer transfer robot 102 to determine the condition of the wafer 120 held by the wafer transfer robot 102.

[0082] In one embodiment, the condition of the wafers 120 may include one or more wafers being cracked, broken, improperly held by the wafer transfer robot 102 , and / or missing from the wafer transfer robot 102 .

[0083] If the method determines that the condition of the wafers 120 includes one or more wafers being cracked, broken, improperly held by the wafer transfer robot 102, and / or omitted from the wafer transfer robot 102, then in step 408, processing of the wafers including operation of the wafer elevator 106 and the wafer transfer robot 102 is stopped, and the operator may check the processing tank 108 for any wafers omitted from the wafer transfer robot 102, or a portion of the wafers, adjust the positioning of any improperly held wafers on the wafer transfer robot 102, remove and / or replace any cracked or broken wafers from the wafer transfer robot 102, replace any contaminated chemical bath 118 or other solutions held in the processing tank 108, and / or replace all wafers currently being processed with a new wafer batch and repeat one or more of the processing procedures.

[0084] The present disclosure provides systems and methods for determining conditions of wafers during processing of the wafers. Wafers may be processed by a semiconductor workbench or other system or assembly for performing processing procedures on wafers for use in, for example, the manufacture of integrated circuits. The systems and methods of the present disclosure are not limited to wafer processing, but may also be used with any system that processes objects that are transported and / or transferred between various chambers or tanks where processing procedures are performed by automated or semi-automated robotic systems.

[0085] In one embodiment, the system includes a wafer elevator, a wafer transfer robot, a vibration sensor attached to the wafer transfer robot, and a processing module communicatively coupled to the vibration sensor. The wafer elevator is used to move at least one wafer to a chemical bath for performing a processing step on the at least one wafer and remove at least one wafer from the chemical bath. The wafer transfer robot is used to hold at least one wafer, place at least one wafer on the wafer elevator, and remove at least one wafer from the wafer elevator. The vibration sensor is used to detect vibration of the wafer transfer robot during holding or removing at least one wafer by the wafer transfer robot and generate a signal based on the vibration. The processing module is used to process the signal for determining a condition of at least one wafer. In one embodiment, the condition of the wafer includes one or more of the at least one wafer being cracked, broken, improperly held, and / or missing. In one embodiment, the system further includes a monitor communicatively coupled to the processing unit. When the processing module determines that the condition of the wafer includes that one or more wafers of the wafer are broken, fractured, improperly held, and / or missing, the processing module generates an alarm signal, and the monitor displays the alarm signal. In one embodiment, the wafer transfer robot includes at least one movable arm. The movable arm has a plurality of slots. When the movable arm moves to remove at least one wafer from the wafer elevator, each slot is used to receive a portion of an edge of one of the wafers, and a vibration sensor is attached to a movable arm. In one embodiment, when a portion of the edge of the wafer is not received by a slot or when the slot receives a portion of the edge of two or more wafers, a wafer is improperly held by the wafer transfer robot. In one embodiment, the system further includes a wafer counting sensor. The wafer counting sensor is used to detect the number of wafers held by the wafer transfer robot after the wafer is removed from the wafer elevator and generate a wafer counting signal. The wafer counting sensor is communicatively coupled to the processing module, and the processing module is further configured to process the wafer counting signal for determining the condition of the wafer held by the wafer transfer robot after removal from the wafer elevator. In one embodiment, the wafer counting sensor includes a plurality of wafer sensors, and each slot includes a wafer sensor for detecting whether the slot contains a portion of an edge of a respective wafer. In one embodiment, the processing area is a processing tank containing a chemical bath. The wafer elevator is configured to move the wafer into the chemical bath for performing a processing step on the wafer and remove at least one wafer from the chemical bath. The system further includes an optical sensor and a monitor. The optical sensor is communicatively coupled to the processing module and positioned to capture an image of at least one of the chemical bath, the wafer elevator, and the wafer transfer robot contained in the processing tank. The monitor is communicatively coupled to the processing module and configured to display the captured image.In one embodiment, a vibration sensor is used to detect vibration of a wafer transfer robot after the wafer transfer robot removes at least one wafer from a wafer elevator, and a processing module is used to process the signal for determining a condition of a wafer held by the wafer transfer robot after the wafer is removed from the wafer elevator.

[0086] In another embodiment, a system for use with a semiconductor workbench is provided. The semiconductor workbench includes at least one semiconductor processing tank and at least one wafer elevator. Each semiconductor processing tank contains a chemical bath, and each wafer elevator is configured to move wafers into and out of the chemical bath of the corresponding semiconductor processing tank. The system includes a wafer transfer robot, which is used to hold at least one wafer, place at least one wafer on the wafer elevator, and remove at least one wafer from the wafer elevator. The system also includes a vibration sensor, which is attached to the wafer transfer robot and is used to detect vibrations of the wafer transfer robot after the wafer transfer robot removes at least one wafer from the wafer elevator, generate a signal based on the vibration, and send the signal to a processing module for determining the condition of at least one wafer held by the wafer transfer robot after removal from the wafer elevator. In one embodiment, the condition of a wafer includes one or more wafers of at least one wafer being cracked, broken, improperly held, and / or missing. In one embodiment, the wafer transfer robot includes at least one movable arm. The movable arm has a plurality of slots. When the movable arm moves to remove at least one wafer from the wafer elevator. Each slot is used to receive a portion of an edge of a wafer of the at least one wafer, and a vibration sensor is attached to at least one movable arm. In one embodiment, when a portion of the edge of the wafer is not received by the slot or when the slot receives a portion of the edge of two or more wafers, the wafer is incorrectly held by the wafer transfer robot. In one embodiment, the system further includes a wafer counting sensor. The wafer counting sensor is used to detect a number of wafers held by the wafer transfer robot after being removed from the wafer elevator and generate a wafer counting signal. The wafer counting sensor is coupled to the processing module, and the processing module is further used to process the wafer counting signal for determining the condition of the wafer held by the wafer transfer robot after being removed from the wafer elevator. In one embodiment, a semiconductor processing area is at least one semiconductor processing container. Each semiconductor processing container contains a chemical bath. Each wafer elevator is configured to move wafers into and out of a chemical bath of a corresponding semiconductor processing container. The system further includes an optical sensor and a monitor. The optical sensor is communicatively coupled to the processing module and positioned to capture images of at least one of a chemical bath, a wafer elevator, and a wafer transfer robot contained in one or more of the processing containers. The monitor is communicatively coupled to the processing module. The monitor is used to display the captured images.

[0087] In yet another embodiment, a method for determining the condition of a wafer during processing of a wafer by a wafer processing system is provided. The method includes processing one or more of the wafers in a processing tank, removing the one or more wafers from the processing tank using a wafer elevator, receiving the one or more wafers at a wafer transfer robot, detecting vibrations of the wafer transfer robot, generating a signal based on the vibrations, and processing the signal for determining the condition of the one or more wafers held by the wafer transfer robot. In one embodiment, the condition of the one or more wafers includes that the one or more wafers are cracked, broken, incorrectly held by the wafer transfer robot, and / or missed from the wafer transfer robot. In one embodiment, the method further includes capturing an image of the processing tank. The step of processing the signal includes processing the signal and the captured image for determining the condition of the one or more wafers held by the wafer transfer robot after the one or more wafers are removed from the wafer elevator by the wafer transfer robot. In one embodiment, the method further includes detecting a number of wafers held by the wafer transfer robot after removal from the wafer elevator and generating a wafer count signal based on the number of detected wafers. The step of processing the signal further includes processing the signal and the wafer count signal for determining a condition of the wafer held by the wafer transfer robot after the wafer is removed from the wafer elevator by the wafer transfer robot. In one embodiment, the wafer comprises a semiconductor wafer and the processing vessel contains a chemical bath.

[0088] The foregoing content summarizes the features of several embodiments so that those skilled in the art can better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they can easily use the present 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.

[0089] Those skilled in the art should also realize that these equivalent constructions do not depart from the spirit and scope of the present disclosure, and that those skilled in the art may make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.

Claims

1. A system for processing a wafer, characterized in that: Include: a wafer elevator for moving at least one wafer into a processing area for performing a processing step on the at least one wafer and removing the at least one wafer from the processing area; a wafer transfer robot for holding the at least one wafer, placing the at least one wafer on the wafer elevator, and removing the at least one wafer from the wafer elevator, the wafer transfer robot comprising at least one movable arm, the at least one movable arm having a plurality of slots, each slot for receiving a portion of an edge of a wafer of the at least one wafer when the at least one movable arm moves to remove the at least one wafer from the wafer elevator; a vibration sensor attached to the at least one movable arm of the wafer transfer robot and configured to detect vibration of the wafer transfer robot during holding or removal of the at least one wafer by the wafer transfer robot and generate a signal based on the vibration; and A processing module is communicatively coupled to the vibration sensor, and is used to process the signal to determine a condition of the at least one wafer, wherein the condition of the at least one wafer includes one or more of the at least one wafer being cracked, broken, improperly retained, and / or missing.

2. The system according to claim 1, characterized in that The at least one movable arm includes a first arm and a second arm opposite to the first arm, and the vibration sensor is located on one of the first arm and the second arm.

3. The system according to claim 1, characterized in that Further included is a monitor communicatively coupled to the processing unit, wherein when the processing module determines that the condition of the at least one wafer includes one or more of the at least one wafer being cracked, broken, improperly retained, and / or missing, the processing module generates an alarm signal and the monitor displays the alarm signal.

4. The system according to claim 1, characterized in that The vibration sensor includes a first vibration sensor and a second vibration sensor, and the second vibration sensor moves relative to the first vibration sensor when the at least one movable arm moves to remove the at least one wafer from the wafer elevator.

5. The system according to claim 1, characterized in that The at least one wafer is improperly held by the wafer transfer robot when the portion of the edge of the wafer is not received by a slot or when the slot receives portions of the edges of two or more wafers.

6. The system according to claim 1, characterized in that Further comprising a wafer counting sensor, the wafer counting sensor is used to detect the number of wafers of the at least one wafer held by the wafer transfer robot after the at least one wafer is removed from the wafer elevator and generate a wafer counting signal, the wafer counting sensor is communicatively coupled to the processing module, and the processing module is further used to process the wafer counting signal for determining the condition of the at least one wafer held by the wafer transfer robot after being removed from the wafer elevator.

7. The system according to claim 6, characterized in that The wafer counting sensor includes a plurality of wafer sensors, and each slot includes a wafer sensor for detecting whether the slot contains a portion of an edge of a respective wafer.

8. The system according to claim 1, characterized in that The processing area is a processing tank containing a chemical bath, wherein the wafer elevator is used to move the at least one wafer into the chemical bath for performing the processing steps on the at least one wafer, and to remove the at least one wafer from the chemical bath, and wherein the system further comprises: an optical sensor communicatively coupled to the process module and positioned to capture an image of at least one of the chemical bath contained within the process tank, the wafer elevator, and the wafer transfer robot; and A monitor is communicatively coupled to the processing module and is used to display the captured image.

9. The system according to claim 1, characterized in that The vibration sensor is used to detect vibration of the wafer transfer robot after the wafer transfer robot removes the at least one wafer from the wafer elevator, and the processing module is used to process the signals for determining a condition of the at least one wafer held by the wafer transfer robot after the at least one wafer is removed from the wafer elevator.

10. A system for processing wafers for use with a semiconductor workbench, the semiconductor workbench comprising at least one semiconductor processing area and at least one wafer elevator, each wafer elevator being configured to move a plurality of wafers into the processing area of ​​a corresponding semiconductor processing tank and to move the plurality of wafers out of the processing area, characterized in that: The system includes: a wafer transfer robot for holding at least one wafer, placing the at least one wafer on the wafer elevator, and removing the at least one wafer from the wafer elevator, the wafer transfer robot comprising at least one movable arm, the at least one movable arm having a plurality of slots, each slot for receiving a portion of an edge of one of the at least one wafer when the at least one movable arm moves to remove the at least one wafer from the wafer elevator; as well as A vibration sensor is attached to the at least one movable arm of the wafer transfer robot and is used to detect vibration of the wafer transfer robot after the wafer transfer robot removes the at least one wafer from the wafer elevator, generate a signal based on the vibration, and send the signal to a processing module for determining a condition of the at least one wafer held by the wafer transfer robot after removal from the wafer elevator, wherein the condition of the at least one wafer includes one or more of the at least one wafer being cracked, broken, improperly held, and / or missing.

11. The system according to claim 10, characterized in that The at least one movable arm includes a first arm and a second arm opposite to the first arm, and the vibration sensor is located on one of the first arm and the second arm.

12. The system according to claim 11, characterized in that The vibration sensor includes a first vibration sensor and a second vibration sensor, and the second vibration sensor moves relative to the first vibration sensor when the at least one movable arm moves to remove the at least one wafer from the wafer elevator.

13. The system according to claim 11, characterized in that The at least one wafer is improperly held by the wafer transfer robot when the portion of the edge of the wafer is not received by a slot or when the slot receives portions of the edges of two or more wafers.

14. The system according to claim 10, characterized in that Further comprising a wafer counting sensor for detecting a wafer number of the at least one wafer held by the wafer transfer robot after being removed from the wafer elevator and generating a wafer counting signal, wherein the wafer counting sensor is coupled to the processing module, and wherein the processing module is further used to process the wafer counting signal for determining the condition of the at least one wafer held by the wafer transfer robot after being removed from the wafer elevator.

15. The system according to claim 10, characterized in that The at least one semiconductor processing region is at least one semiconductor processing vessel, wherein each semiconductor processing vessel contains a chemical bath, wherein each wafer elevator is configured to move the wafers into and out of the chemical bath of a corresponding semiconductor processing vessel, and wherein the system further comprises: an optical sensor communicatively coupled to the process module and positioned to capture images of at least one or more of the chemical bath, the wafer elevator, and the wafer transfer robot contained within one or more of the at least one process container; and A monitor is communicatively coupled to the processing module, and is used for displaying the images captured by the optical sensor.

16. A method of processing wafers, for determining conditions of a plurality of wafers during processing of the plurality of wafers by a wafer processing system, characterized in that: The method includes: processing one or more wafers of the plurality of wafers in a processing vessel; removing the one or more wafers from the processing container using a wafer elevator; receiving the one or more wafers at a wafer transfer robot, wherein the wafer transfer robot comprises at least one movable arm, the at least one movable arm having a plurality of slots, each slot being configured to receive a portion of an edge of one of the at least one wafers when the at least one movable arm moves to remove the at least one wafer from the wafer elevator, and a vibration sensor is attached to the at least one movable arm of the wafer transfer robot; detecting vibration of the wafer transfer robot via the vibration sensor; generating a signal based on the vibration; and The signal is processed for determining a condition of the one or more wafers held by the wafer transfer robot, the condition of the one or more wafers comprising one or more wafers being cracked, broken, improperly held by the wafer transfer robot and / or missing from the wafer transfer robot.

17. The method according to claim 16, characterized in that The at least one movable arm includes a first arm and a second arm opposite to the first arm, and the vibration sensor is located on one of the first arm and the second arm.

18. The method according to claim 16, characterized in that Further comprising: capturing an image of the processing container, and wherein the step of processing the signal comprises processing the signal and the captured image for determining the condition of the one or more wafers maintained by the wafer transfer robot after the one or more wafers are removed from the wafer elevator by the wafer transfer robot.

19. The method according to claim 16, characterized in that Further including: detecting a number of the plurality of wafers held by the wafer transfer robot after being removed from the wafer elevator; and generating a wafer counting signal based on the detected number of wafers, Wherein the step of processing the signal further includes processing the signal and the plurality of wafer counting signals for determining the condition of the plurality of wafers held by the wafer transfer robot after the plurality of wafers are removed from the wafer elevator by the wafer transfer robot.

20. The method according to claim 16, characterized in that The wafers include semiconductor wafers and the processing container contains a chemical bath.

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