APPARATUS AND METHOD FOR PROCESSING WAFER STORAGE Cassette

Abstract

The invention discloses equipment and a method for processing a wafer storage box. The method for processing the wafer storage box comprises the following steps: placing the wafer storage box on a table; opening the wafer storage box to expose the sealing strip of the wafer storage box; the light beam is guided to the position above the sealing strip; judging whether the light beam is blocked by a sealing strip; and in response to determining that the light beam is blocked by the sealing strip, performing a maintenance process on the sealing strip.

Description

Technical Field

[0001] This disclosure relates to an apparatus and method for handling a wafer cassette. Background Art

[0002] Wafers are used in the production of silicon semiconductor integrated circuits. Wafers can be processed into various circuit element structures and become integrated circuit products with specific electrical functions. Wafers can be both thin and brittle. Therefore, to transport wafers, storage and transport cassettes are used to carry the wafers, thereby enhancing their stability. Summary of the Invention

[0003] According to some embodiments of the present disclosure, a method for handling a wafer cassette includes placing the wafer cassette on a stage; opening the wafer cassette such that a sealing strip of the wafer cassette is exposed; directing a light beam above the sealing strip; determining whether the light beam is blocked by the sealing strip; and in response to determining that the light beam is blocked by the sealing strip, performing a maintenance process on the sealing strip.

[0004] According to some embodiments of the present disclosure, a method for handling a wafer cassette includes opening the wafer cassette by using a clamping mechanism; determining whether a sealing strip has detached from a lug on a first side of the wafer cassette; and in response to determining that the sealing strip has detached from the lug on the first side of the wafer cassette, performing a first maintenance process on the sealing strip.

[0005] According to some embodiments of the present disclosure, an apparatus for handling a wafer cassette includes a first stage, a first clamping mechanism, and a first optical inspection device. The first stage is configured to support the wafer cassette. The first clamping mechanism is above the first stage and is configured to clamp and move a lid of the wafer cassette. The first optical inspection device is above the first stage, wherein the first optical inspection device includes a light emitter configured to generate a light beam and a light sensor configured to receive the light beam, wherein when viewed from the top, a path of the light beam overlaps with the first stage. Brief Description of the Drawings

[0006] Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying Figure 1 drawings. It should be noted that, in accordance with standard industry practice, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0007] Figure 1 is a flowchart of a method for handling a wafer cassette according to some embodiments of the present disclosure;

[0008] Figures 2 to 7A is a schematic diagram of an apparatus for handling a wafer cassette according to some embodiments of the present disclosure;

[0009] Figure 7B and Figure 7Cis a side view showing the detection status of a wafer cassette according to some embodiments of the present disclosure;

[0010] Figures 8A to 8D is a top view showing the steps for detecting four sides of a wafer cassette according to some embodiments of the present disclosure;

[0011] Figure 9A is a schematic diagram of a device for processing a wafer cassette according to some embodiments of the present disclosure;

[0012] Figure 9B is Figure 9A a simplified schematic front view of the device;

[0013] Figure 9C is Figure 9A a schematic diagram of the image sensor of the device in;

[0014] Figure 10 is a flowchart of a method for processing a wafer cassette according to some embodiments of the present disclosure.

[0015]

Symbol Description

[0016] 100: Device

[0017] 102: Wall

[0018] 104: Wheel

[0019] 110: Platform

[0020] 120: Rotating table

[0021] 120A~120B: Rotating table

[0022] 122: Positioning protrusion

[0023] 130: Position sensor

[0024] 140: Clamping mechanism

[0025] 140A~140B: Clamping mechanism

[0026] 142: Clamping body

[0027] 144: Fixture

[0028] 144A: Arm

[0029] 144F: Finger

[0030] 146: Vertical guide rail

[0031] 160: Unlocking mechanism

[0032] 160A~160B: Unlocking mechanism

[0033] 162: Main body

[0034] 164: Unlock projection

[0035] 170: Optical inspection device

[0036] 170A~170B: Optical inspection device

[0037] 172: Light emitter

[0038] 172A~172B: Light emitter

[0039] 174: Light sensor

[0040] 174A~174B: Light sensor

[0041] 180: Work platform

[0042] 190: Rotary table

[0043] 200: Wafer storage cassette

[0044] 200A~200B: Wafer storage cassette

[0045] 210: Housing

[0046] 210I: Internal volume

[0047] 212: Main body

[0048] 212R: Lug

[0049] 214: Component

[0050] 220: Cover

[0051] 222: Cover body

[0052] 224: Extension side

[0053] 224H: Hole

[0054] 230: Sealing strip

[0055] 231~234: Part

[0056] 300: Wafer carrier

[0057] 400: Image sensor

[0058] BH: Beam height

[0059] BS1: First side

[0060] BS2: Second side

[0061] BS3: Third side

[0062] BS4: The fourth side

[0063] BW: Beam width

[0064] CR: Controller

[0065] HA~HB: Height

[0066] BA: Horizontal bar

[0067] LB: Light beam

[0068] LBA~LBB: Light beam

[0069] LHA~LHB: Vertical distance

[0070] M1: Method

[0071] M1': Method

[0072] OP: Optical path

[0073] OPD: Vertical distance

[0074] RM1~RM2: Robot arm

[0075] S01~S02: Steps

[0076] S1~S10: Steps

[0077] S1': Step

[0078] VD: Vertical distance Detailed implementation manners

[0079] The following disclosure provides many different embodiments, or examples, for implementing the different features of the provided subject matter. Specific examples of components and configurations are described below to simplify the present disclosure. Of course, these are only examples and are not intended to be restrictive. For example, in the following description, the formation of a first feature above or on a second feature may include embodiments in which the first feature and the second feature are formed in direct contact, and may also include embodiments in which additional features may be formed between the first feature and the second feature such that the first feature and the second feature are not in direct contact. In addition, the present disclosure may repeat reference numerals and / or letters in various examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.

[0080] In addition, for ease of description, spatial relative terms, such as "below", "beneath", "lower", "above", "upper", and the like, may be used herein to describe the relationship of one element or feature shown in the figures to another (one or more) element or feature. The spatial relative terms are intended to cover 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 spatial relative descriptors used herein may be interpreted accordingly.

[0081] Figure 1 is a flowchart of a method for processing a wafer storage cassette according to some embodiments of the present disclosure. Method M1 includes steps S1 to S10. At step S1, the wafer storage cassette is moved onto the processing device by a robotic arm. At step S2, the wafer storage cassette is opened by the processing device. At step S3, a laser beam is used to detect the attachment integrity between the sealing strip of the wafer storage cassette and the side surface of the housing. At step S4, the attachment integrity is evaluated to determine whether the attachment integrity between the sealing strip of the wafer storage cassette and the side surface of the housing meets an acceptable threshold. At step S5, an alarm event occurs and a maintenance process is performed by an operator. At step S6, it is determined whether the wafer storage cassette has undergone three rotation cycles. At step S7, if the wafer storage cassette has not completed three rotation cycles, an additional rotation cycle of the wafer storage cassette is initiated to rotate the lower side surface of the housing to a position directly below the laser beam. At step S8, if the wafer storage cassette has undergone three rotation cycles, the wafer is moved into or out of the wafer storage cassette. At step S9, the wafer storage cassette is closed by using the processing device. At step S10, the wafer storage cassette is removed from the processing device by using the robotic arm. It should be understood that additional steps may be provided before, during, and after the steps S1 to S10 shown, and for additional embodiments of the method, some of the following steps S1 to S10 may be replaced or eliminated. The order of the operations / processes may be interchanged. Figure 1 Additional steps may be provided before, during, and after the steps S1 to S10 shown, and for additional embodiments of the method, some of the following steps S1 to S10 may be replaced or eliminated. The order of the operations / processes may be interchanged.

[0082] Figures 2 to 7A is a schematic diagram of a device 100 for processing a wafer storage cassette 200 according to some embodiments of the present disclosure. Refer to Figure 2。In some embodiments of the present disclosure, the apparatus 100 includes a work platform 110, a turntable 120 above the work platform 110, a position sensor 130, a clamping mechanism 140, an unlocking mechanism 160, and an optical inspection device 170. The work platform 110 has a top surface substantially parallel to the X direction and the Y direction perpendicular to the X direction. The turntable 120 is above the work platform 110 and is used to rotate the wafer cassette 200, and its central axis extends along the Z direction orthogonal to the X direction and the Y direction. The position sensor 130 can detect the loading or unloading of the wafer cassette. The clamping mechanism 140 can be disposed directly above the turntable 120 and is used to open and close the wafer cassette 200. The unlocking mechanism 160 can be disposed on the opposite side of the turntable 120 and is used to unlock and lock the wafer cassette 200. The optical inspection device 170 can be disposed above the turntable 120 and is used to detect the condition of the sealing strip of the wafer cassette 200. The optical inspection device 170 can include an optical emitter 172 that generates a light beam LB along the X direction and a light sensor 174 that receives the light beam LB. In some embodiments, the apparatus 100 can include a wall 102 for supporting the clamping mechanism 140 and the optical inspection device 170. For example, the apparatus 100 can further include a horizontal rod BA fixed to the wall 102 and supporting the optical emitter 172 and the light sensor 174.

[0083] The apparatus 100 can further include a controller CR configured to receive information from the position sensor 130 and the optical inspection device 170 and to control the operations of the turntable 120, the clamping mechanism 140, the position sensor 130, the unlocking mechanism 160, and the optical inspection device 170. The controller CR can include a computer-readable storage medium and a processor coupled to the computer-readable storage medium. The computer-readable storage medium stores a program for controlling the respective steps of a method M1 (refer to Figure 1 ) executed by the apparatus 100. The controller CR controls the operations of the apparatus 100 and the robotic arm by using the processor that reads and executes the program stored in the storage medium. The program can be a program stored in the computer-readable storage medium or a program installed in the storage medium of the controller CR.

[0084] Refer to Figure 1 and Figure 3。Method M1 begins with step S1, where the wafer cassette 200 is moved onto the processing device 100 by the robotic arm RM1. The wafer cassette 200 is placed on the area of the rotating table 120. In some embodiments, the rotating table 120 may have positioning protrusions 122 for defining the area of the rotating table 120 where the wafer cassette 200 is placed. In some embodiments, the rotating table 120 is capable of rotating the wafer cassette 200. For example, the rotating table 120 is an electric rotating table that restricts movement to a single rotation axis (e.g., along the Z direction) and precisely controls the angular position about that rotation axis (e.g., along the Z direction). The motor for controlling the rotating table 120 may be disposed in the working platform 110.

[0085] In some embodiments, the position sensor 130 (refer to Figure 2 ) may be disposed on the area of the rotating table 120 where the wafer cassette 200 is placed. The position sensor 130 (refer to Figure 2 ) can detect the loading of the wafer cassette 200. For example, the position sensor 130 (refer to Figure 2 ) may include an opaque spring plate and an optical interrupter, where the optical interrupter includes an optical emitter and an optical sensor. When the wafer cassette 200 is placed on the area of the rotating table 120, the opaque spring plate of the position sensor 130 (refer to Figure 2 ) may be pressed by the gravity of the wafer cassette 200 into the space between the optical emitter and the optical sensor, thereby blocking the light emitted from the optical emitter from being detected by the optical sensor. The non-detection state indicates the loading of the wafer cassette 200. On the other hand, the position sensor 130 (refer to Figure 2 ) can also detect the unloading of the wafer cassette 200. For example, when the wafer cassette 200 is not placed on the area of the rotating table 120, the opaque spring plate of the position sensor 130 (refer to Figure 2 ) will return to its initial position and not be in the space between the optical emitter and the optical sensor, such that the light emitted from the optical emitter will be detected by the optical sensor. The detection state can indicate the unloading of the wafer cassette 200.

[0086] In some embodiments, the wafer cassette 200 has a housing 210 and a cover 220. The cover 220 may have a cover body 222 and a pair of extending side portions 224 connected to the cover body 222. The extending side portions 224 of the cover 220 may have holes 224H for easy gripping. In some embodiments, the housing 210 may have a main body 212 surrounding the internal volume of the housing 210 and elements 214 to be locked with elements of the extending side portions 224 of the cover 220. The wafer cassette 200 may also be referred to as a wafer shipping cassette in context.

[0087] Refer to Figure 1 and Figures 4 to 6。Method M1 proceeds to step S2, where the wafer storage cassette 200 is opened by the processing device 100. Refer to Figure 4 。The clamping mechanism 140 has a clamping body 142, a pair of clamps 144, and a vertical guide rail 146. Each of the clamps 144 may have an arm 144A and a plurality of fingers 144F, where the fingers 144F are supported by the arm 144A, and the top portion of the arm 144A is connected to the clamping body 142. The clamping body 142 may be a vehicle capable of moving up or down along the Z direction via the vertical guide rail 146. The clamps 144 may move toward or away from the wafer storage cassette 200 along the X direction. In Figure 4 this case, the clamping body 142 moves downward, and the clamps 144 move toward the wafer storage cassette 200, where the fingers 144F are inserted into the holes 224H in the extended side portions 224 of the cover 220. Thus, the clamping mechanism 140 clamps the cover 220.

[0088] Refer to Figure 5 。The unlocking mechanism 160 has a main body 162 and an unlocking protrusion 164. The main body 162 may move toward or away from the wafer storage cassette 200 along the X direction. The unlocking protrusion 164 may move up or down along the Z direction. In Figure 5 this case, the main body 162 moves toward the wafer storage cassette 200, and the unlocking protrusion 164 moves upward to release the locking between the components of the extended side portion 224 of the cover 220 and the corresponding components 214 of the housing 210. Thus, the housing 210 of the wafer storage cassette 200 and the cover 220 are unlocked.

[0089] Refer to Figure 6 。The clamping body 142 moves upward along the Z direction. As the fingers 144F are inserted into the holes 224H in the extended side portions 224 of the cover 220, the cover 220 of the wafer storage cassette 200 is clamped by the clamping mechanism 140 and is detached from the housing 210 of the wafer storage cassette 200 as it moves along the Z direction. In the illustrated embodiment, the wafer carrier 300 is disposed in the housing 210. The wafer carrier 300 may have a plurality of slots for receiving wafers. In some embodiments, the wafer carrier 300 is empty, so no wafers are supported by the wafer carrier 300. In some alternative embodiments, the wafer storage cassette 200 contains wafers.

[0090] In some embodiments, refer to Figure 7A, the wafer storage cassette 200 may include a sealing strip 230 above the lug 212R of the main body 212. For example, the main body 212 may have four sides surrounding the internal volume 210I of the housing 210, and the sealing strip 230 has four portions 231-234 respectively above the lugs 212R on the four sides of the main body 212. The sealing strip 230 may be disposed between the housing 210 and the cover 220 of the wafer storage cassette 200. The sealing strip 230 may isolate the internal volume of the wafer storage cassette 200 from the external environment. Thus, contaminants such as foreign particles and corrosive gases are excluded from the internal volume of the wafer storage cassette 200. The sealing strip 230 may include a suitable rubber material. For example, in some embodiments, the sealing strip 230 may be a silicone strip. In some embodiments, the sealing strip 230 may be made of an opaque material. For example, the sealing strip 230 may have a light transmittance of less than about 50% within the operating wavelength range of the optical inspection device 170 (e.g., at the wavelength of the light beam LB), or even less than about 20% within the operating wavelength range of the optical inspection device 170 (e.g., at the wavelength of the light beam LB). For example, the sealing strip 230 may have a light absorption rate of greater than about 50% within the operating wavelength range of the optical inspection device 170 (e.g., at the wavelength of the light beam LB), or even greater than about 80% within the operating wavelength range of the optical inspection device 170 (e.g., at the wavelength of the light beam LB).

[0091] Reference Figure 1 and Figure 7A . The method M1 proceeds to step S3, where the attachment integrity between the sealing strip 230 of the wafer storage cassette 200 and the side surface of the housing 210 is detected using the light beam LB. Figure 7B and Figure 7C is a side view showing the detection state of the wafer storage cassette 200 according to some embodiments of the present disclosure. Reference Figures 7A to 7C , the optical path of the light beam LB is exactly above the sealing strip 230. The optical path of the light beam LB is higher than and substantially parallel to the top surface of the lug 212R on the side surface of the main body 212. In Figure 7B , when the sealing strip 230 is firmly attached to the lug 212R on the side surface of the main body 212 (i.e., the sealing strip 230 completely conforms to the lug 212R in the cross-sectional through hole as shown in Figure 7B ), the light beam LB is not blocked and can be detected by the photosensor 174. In Figure 7C , when the sealing strip 230 is partially detached from the lug 212R on the side surface of the main body 212 (i.e., the sealing strip 230 does not completely conform to the lug 212R in the cross-sectional view), the light beam LB is blocked by the sealing strip 230 and cannot be detected by the photosensor 174.

[0092] Method M1 proceeds to step S4, where the attachment integrity detected in the previous step S3 is evaluated to determine whether the detected attachment integrity between the sealing strip 230 of the wafer cassette 200 and the first side meets an acceptable threshold. The evaluation relies on determining whether the light beam LB is blocked by the sealing strip 230. For example, if the light intensity measured by the light sensor 174 is greater than a predetermined threshold, the detected attachment integrity between the sealing strip 230 of the wafer cassette 200 and the lug 212R on the side of the housing 210 is determined to be acceptable. And, if the light intensity measured by the light sensor 174 is less than the predetermined threshold, the detected attachment integrity between the sealing strip 230 of the wafer cassette 200 and the lug 212R on the side of the housing 210 is determined to be unacceptable. In some embodiments, the predetermined threshold may be a predetermined ratio of the light intensity of the light beam LB emitted from the light emitter 172, where the predetermined ratio may range from about 10% to about 80%, such as about 20%.

[0093] Once the detected attachment integrity between the sealing strip 230 of the wafer cassette 200 and the lug 212R on the side of the housing 210 is determined to be unacceptable, method M1 proceeds to step S5, where an alarm event occurs and a maintenance process is performed by the operator. In some embodiments, during the maintenance process, the operator can be notified by the alarm event and manually push the sealing strip 230 back to contact the lug 212R on the side of the housing 210 of the wafer cassette 200. Through the maintenance process, the sealing strip 230 is restored to firmly attach to the lug 212R on the side of the housing 210 of the wafer cassette 200. In other words, the maintenance process changes Figure 7C the state shown in Figure 7B to the state shown in Figure 7C In some embodiments, the maintenance process may include adjusting the position of the sealing strip 230 such that the light beam LB blocked by the sealing strip 230 as shown in Figure 7B is changed to not being blocked by the sealing strip 230, as shown in Figure 7C In some embodiments, the maintenance process may include reducing the gap between the sealing strip 230 and the lug 212R on the side of the housing 210. For example, as shown in Figure 7B the gap between the sealing strip 230 and the lug 212R is reduced or eliminated, so that there is no gap between the sealing strip 230 and the lug 212R, as shown in

[0094] In some embodiments, the light beam LB can be a laser beam, and the light emitter 172 can be a laser source, such as a laser diode. In some embodiments, the light beam LB can be a collimated beam with a divergence angle less than 2 mrad. In some embodiments of the present disclosure, the light beam LB can have a visible wavelength ranging from 300 nanometers to about 700 nanometers. In some alternative embodiments, the light beam LB can have any other suitable wavelength. The light sensor 174 can have an operable wavelength range that overlaps or covers the wavelength range of the light beam LB, such that the light sensor 174 can generate an output signal indicative of the intensity of the received light. In some embodiments, the light beam LB can be monochromatic light. For example, the light beam LB can be a red laser beam or a green laser beam. In some alternative embodiments, the light beam LB can be polychromatic light.

[0095] In some embodiments, the light beam LB is spaced apart from the sealing strip 230 by a vertical distance VD ranging from about 0.5 millimeters to about 1 millimeter (refer to Figure 7B ). In other words, the bottom of the profile of the light beam LB is higher than the top surface of the sealing strip 230 by a vertical distance VD (refer to Figure 7B ). If the vertical distance VD (refer to Figure 7B ) is greater than about 1 millimeter, the sealing strip 230 may peel off without an alarm. If the vertical distance VD (refer to Figure 7B ) is less than about 0.5 millimeter, an alarm event may occur when the sealing strip 230 has not peeled off. For example, in some embodiments, the light beam LB can have a beam height BH (or beam diameter) ranging from about 0.5 millimeters to about 1.5 millimeters. Therefore, the optical path OP of the light beam LB (or the optical path of the optical inspection device 170 including the light emitter 172 and the light sensor 174) can be spaced apart from the sealing strip 230 by a vertical distance OPD ranging from about 0.75 millimeters to about 1.75 millimeters. If the vertical distance OPD (refer to Figure 7B ) is greater than about 1.75 millimeters, the sealing strip 230 may peel off without an alarm. If the vertical distance OPD (refer to Figure 7B ) is less than about 0.75 millimeter, an alarm event may occur when the sealing strip 230 has not peeled off.

[0096] In some embodiments, the light beam LB can have a suitable beam size for high inspection accuracy. For example, the light beam LB can have a beam width BW (or beam diameter) that is less than the width of the sealing strip 230 (refer to Figure 8A ), such that the sealing strip 230 can completely block the contact between the light beam LB and the light sensor 174. In some embodiments, the light beam LB can have a beam width BW (or beam diameter) that is equal to or greater than the width of the sealing strip 230 (refer to Figure 8A), and the sealing strip 230 can block a part of the light beam LB, which will cause an observable change in the light intensity detected by the light sensor 174. For example, the beam width BW (or beam diameter) of the light beam LB can be in the range from about 0.5 mm to about 1.5 mm. In some embodiments, the light beam LB can have a circular cross-sectional profile such that the beam width BW is substantially equal to the beam height BH. In some embodiments, the light beam LB can have other cross-sectional profiles, and the beam width BW can be greater than or less than the beam height BH.

[0097] After the maintenance process at step S5, the method M1 proceeds to step S6. Additionally, if the detected attachment integrity between the sealing strip 230 of the wafer cassette 200 and the lug 212R on the side of the housing 210 is determined to be acceptable, the method M1 skips step S5 and proceeds to step S6. At step S6, it is determined whether the wafer cassette 200 has undergone three rotation cycles, where each rotation cycle involves a rotation of substantially 90 degrees or a 90-degree angular movement. In some embodiments, the controller CR can determine whether the wafer cassette 200 has completed three rotation cycles by tracking the number of rotations performed by the rotary table 120 after the wafer cassette is placed on the rotary table 120. If the wafer cassette 200 has not completed three rotation cycles, the method M1 proceeds to step S7 to initiate a rotation cycle of the wafer cassette, rotating the lower side of the housing 210 around the central axis of the housing 210 to a position directly below the light beam LB. By rotating the wafer cassette 200, steps S3 - S5 are repeatedly performed on the four sides of the housing 210 until the wafer cassette 200 has completed three rotation cycles, as Figures 8A to 8D shown.

[0098] Figures 8A to 8D is a top view showing the steps for detecting the four sides of the wafer cassette 200 according to some embodiments of the present disclosure. When viewed from the top, the light beam LB can overlap with the rotary table 120. In Figure 8AIn [description], the first side BS1 of the housing 210 is directly below the light beam LB (i.e., vertically overlaps with the light beam LB in the Z direction), and the light beam LB is directly above the portion 231 of the sealing strip 230 above the first side BS1. For example, when viewed from the top, the light beam LB is parallel to and overlaps with the first side BS1. Therefore, at step S3, the attachment integrity between the portion 231 of the sealing strip 230 and the first side BS1 is detected by the light beam LB. Then at step S4, the attachment integrity between the portion 231 of the sealing strip 230 and the first side BS1 is evaluated. According to the evaluation result, the maintenance process at step S5 can be performed on the portion 231 of the sealing strip 230. After step S4 (and optional step S5), since the wafer cassette 200 has not completed three rotation cycles, the method M1 proceeds to step S7, where the wafer cassette 200 is rotated to rotate the second side BS2 of the housing 210 to a position directly below the light beam LB, as Figure 8B shown. For example, in order to rotate the second side BS2 of the housing 210 to a position directly below the light beam LB, the wafer cassette 200 rotates around its central axis in the Z direction within a range from about 85 degrees to about 95 degrees, such as a first rotation angle of 90 degrees. In other words, the rotation cycle involves a rotation of substantially 90 degrees or a 90-degree angular movement.

[0099] In Figure 8B [description], the second side BS2 of the housing 210 is directly below the light beam LB (i.e., vertically overlaps with the light beam LB in the Z direction), and the light beam LB is directly above the portion 232 of the sealing strip 230 above the second side BS2. For example, when viewed from the top, the light beam LB is parallel to and overlaps with the second side BS2. Therefore, at step S3, the attachment integrity between the portion 232 of the sealing strip 230 and the second side BS2 is detected by the light beam LB. Then at step S4, the attachment integrity between the portion 232 of the sealing strip 230 and the second side BS2 is evaluated. According to the evaluation result, the maintenance process at step S5 can be performed on the portion 232 of the sealing strip 230. After step S4 (and optional step S5), since the wafer cassette 200 has not completed three rotation cycles, the method M1 proceeds to step S7, where the wafer cassette 200 is rotated to rotate the third side BS3 of the housing 210 to a position directly below the light beam LB, as Figure 8C shown. For example, in order to rotate the third side BS3 of the housing 210 to a position directly below the light beam LB, the wafer cassette 200 rotates around its central axis extending in the Z direction within a range from about 85 degrees to about 95 degrees, such as a second rotation angle of 90 degrees. In other words, this rotation cycle also involves a rotation of substantially 90 degrees or a 90-degree angular movement, which is the same as the previous rotation cycle of rotating the second side BS2 to a position directly below the light beam LB.

[0100] In Figure 8CIn [description], the third side BS3 of the housing 210 is directly below (i.e., vertically overlapped with) the light beam LB, and the light beam LB is directly above the portion 233 of the sealing strip 230 that is above the third side BS3. For example, when viewed from the top, the light beam LB is parallel to and overlaps with the third side BS3. Therefore, at step S3, the attachment integrity between the portion 233 of the sealing strip 230 and the third side BS3 is detected by the light beam LB. The detected attachment integrity between the portion 233 of the sealing strip 230 and the third side BS3 is evaluated at step S4. According to the evaluation result, the maintenance process at step S5 can be performed on the portion 233 of the sealing strip 230. After step S4 (and optional step S5), since the wafer cassette 200 has not completed three rotation cycles, the method M1 proceeds to step S7, where the wafer cassette 200 is rotated so that the fourth side BS4 of the housing 210 rotates to be directly below the light beam LB, as Figure 8D shown. For example, in order to rotate the fourth side BS4 of the housing 210 to be directly below the light beam LB, the wafer cassette 200 rotates around its central axis extending in the Z direction within a range from about 85 degrees to about 95 degrees, such as a third rotation angle of 90 degrees. In other words, this rotation cycle also involves a rotation of substantially 90 degrees or an angular movement of 90 degrees, which is the same as the previous rotation cycles that rotated the second side BS2 and the third side BS3 to be directly below the light beam LB.

[0101] In Figure 8D [description], the fourth side BS4 of the housing 210 is directly below the light beam LB, and the light beam LB is directly above the portion 234 of the sealing strip 230 that is above the fourth side BS4. For example, when viewed from the top, the light beam LB is parallel to and overlaps with the fourth side BS4. Therefore, at step S3, the attachment integrity between the portion 234 of the sealing strip 230 and the fourth side BS4 is detected by the light beam LB. The detected attachment integrity between the portion 234 of the sealing strip 230 and the fourth side BS4 is evaluated at step S4. According to the evaluation result, the maintenance process at step S5 can be performed on the portion 234 of the sealing strip 230. After step S4 (and optional step S5), since the wafer cassette 200 has undergone three rotation cycles, the method M1 proceeds to step S8.

[0102] Refer to Figure 1 and Figure 7A, at step S8, for example, the wafer is moved into or out of the wafer storage cassette 200 by the robotic arm RM2. For example, in some embodiments, the robotic arm RM2 can move the wafer carrier 300 supporting multiple wafers out of the wafer storage cassette 200, and then the wafers can be transferred to other wafer carriers, such as a wafer boat, a wafer cassette, a front opening unified pod (FOUP), or the like, by other robotic arms. The wafer can be a disk-shaped silicon wafer, a glass wafer, a sapphire wafer, or the like. After the wafers are transferred from the wafer carrier 300 to other wafer carriers, the wafers can be transferred among various semiconductor manufacturing apparatuses and / or processed by various semiconductor manufacturing processes. In some alternative embodiments, after being transferred among various semiconductor manufacturing apparatuses and / or processed by various semiconductor manufacturing processes, the wafers are transferred from other wafer carriers to the wafer carrier 300, and then the robotic arm RM2 can move the wafer carrier 300 supporting the wafers into the wafer storage cassette 200. In some embodiments, after step S6 and before step S8, the wafer storage cassette 200 can be rotated to rotate the first side BS1 of the housing 210 directly under the light beam LB, as Figure 8A shown.

[0103] Refer to Figure 1 . The method M1 then proceeds to step S9, where the wafer storage cassette 200 is closed by using the processing apparatus 100. For example, the clamping body 142 of the clamping mechanism 140 (refer to Figure 5 and Figure 6 ) can move downward to place the cover 220 back onto the housing 210, in the corresponding configuration as Figure 5 shown. The unlocking protrusion 164 of the unlocking mechanism 160 (refer to Figure 5 ) can move downward along the axis Z to lock the cover 220 and the housing 210, in the corresponding configuration as Figure 4 shown. Then, the fingers 144F of the clamp 144 of the clamping mechanism 140 (refer to Figure 4 ) can move outward from the holes 224H of the extending side portion 224 such that the clamping mechanism 140 does not clamp the cover 220, in the corresponding configuration as Figure 3 shown. After the wafer storage cassette 200 is closed, refer to Figure 7A , the method M1 proceeds to step S10, where the wafer storage cassette 200 is moved away from the turntable 120 of the processing apparatus 100 by using the robotic arm RM1, for example, moved to a storage room. The robotic arm RM1 can then move another wafer storage cassette 200 onto the processing apparatus 100. The closing operation at step S9 and the cassette moving operation at step S10 respectively correspond to the opening operation at step S2 with respect to Figures 3 to 6 and the operation at step S2 with respect to Figures 1 to 2The cassette moving operation at step S1 thereof, and thus is not specifically depicted herein.

[0104] Figure 9A is a schematic diagram of a device 100 for processing a wafer storage cassette 200 according to some embodiments of the present disclosure. The device 100 may include a work platform 180, a turntable 190 above the platform 180, and one or more image sensors 400. The image sensor 400 may detect information about the type of the wafer storage cassette 200. For example, the wafer storage cassette 200 may have an identification code, a mark, or other features for identification / recognition, and the image sensor 400 may detect information about the identification code, the mark, or the features through an image. The turntable 190 may rotate the wafer storage cassette 200 about its central axis extending in the Z direction, thereby allowing the image sensor 400 to detect multiple sides of the wafer storage cassette 200. A motor for controlling the turntable 190 may be disposed in the work platform 180. For example, the turntable 190 is an electric turntable that restricts movement to a single rotation axis (e.g., along the Z direction) and precisely controls the angular position around the rotation axis (e.g., along the Z direction). A controller CR of the device 100 may receive the detected information from the image sensor 400 and determine the type of the wafer storage cassette 200 based on the detected information. According to the determined type of the wafer storage cassette 200, the robotic arm RM1 may move the wafer storage cassette 200 to a corresponding area for opening the wafer storage cassette 200.

[0105] Reference Figure 9A and Figure 9B . Figure 9B is [[ID= a simplified schematic front view of the device. In some embodiments, a first type of wafer storage cassette 200 (designated as wafer storage cassette 200A) may have a different structure and / or material from a second type of wafer storage cassette 200 (designated as wafer storage cassette 200B). For example, the joint between the housing 210 and the lid 220 of the wafer storage cassette 200A may be higher than the joint between the housing 210 and the lid 220 of the wafer storage cassette 200B, such that the sealing strip 230 of the wafer storage cassette 200A may be higher than the sealing strip 230 of the wafer storage cassette 200B. In other words, the sealing strips 230 of the wafer storage cassettes 200A and 200B may be at different levels. For example, the height HA of the sealing strip 230 of the wafer storage cassette 200A measured from the platform 110 is greater than the height HB of the sealing strip 230 of the wafer storage cassette 200B measured from the platform 110. In some embodiments, the wafer storage cassettes 200A and 200B have different heights. In some embodiments, the wafer storage cassette 200A is made of an opaque plastic material, such as a polypropylene material. In some embodiments, the wafer storage cassette 200B is made of a transparent or translucent material, such as a polycarbonate material, that allows visual inspection without opening.

[0106] In some embodiments, to open the wafer cassette 200, the apparatus 100 may include two rotary tables 120A and 120B above the work platform 110, two clamping mechanisms 140A and 140B respectively above the rotary tables 120A and 120B, two unlocking mechanisms 160A and 160B, and two optical inspection devices 170A and 170B. Due to the structural differences between the two types of wafer cassettes 200A and 200B, the clamping mechanisms 140A and 140B, the unlocking mechanisms 160A and 160B, and the two optical inspection devices 170A and 170B may have different configurations. In some instances, the optical inspection devices 170A and 170B are at different levels. For example, the vertical distance LHA between the optical inspection device 170A (or the light beam LBA emitted from the light emitter 172A and received by the light sensor 174A) and the top surface of the platform 110 is greater than the vertical distance LHB between the optical inspection device 170B (or the light beam LBB emitted from the light emitter 172B and received by the light sensor 174B) and the top surface of the platform 110. In some instances, the clamping mechanisms 140A and 140B are at different levels. In some instances, the clamping mechanisms 140A and 140B may be at the same level. In some instances, the space between the unlocking mechanisms 160A is greater than or less than the space between the unlocking mechanisms 160B. In some instances, the space between the unlocking mechanisms 160A may be equal to the space between the unlocking mechanisms 160B.

[0107] In some embodiments, the apparatus 100 may further include a controller CR configured to receive information from the optical inspection devices 170A and 170B and to control the operation of the rotary tables 120A and 120B, the clamping mechanisms 140A and 140B, the unlocking mechanisms 160A and 160B, and the optical inspection devices 170A and 170B. The controller CR may be disposed in a housing below the work platform 110. The controller CR may include a computer-readable storage medium and a processor coupled to the computer-readable storage medium. The computer-readable storage medium stores control for a method M1' executed by the apparatus 100 (refer to ​The program for each step of (). The controller CR controls the operations of the device 100 and the robotic arm RM1 by using a processor that reads and executes a program stored in a storage medium. The program can be a program stored in a computer-readable storage medium or a program installed in the storage medium of the controller CR. For example, the processor can be a central processing unit (CPU) that serves as an operation core and a control core, or a large-scale integrated circuit. The device 100 can further include wheels 104 and / or guide rails to facilitate movement. Other details of the components of the device 100 (e.g., the rotary tables 120A and 120B, the clamping mechanisms 140A and 140B, the unlocking mechanisms 160A and 160B, and the optical inspection devices 170A and 170B) are similar to ​ the rotary table 120, the clamping mechanism 140, the unlocking mechanism 160, and the optical inspection device 170 in

[0108] ​ is ​ a schematic diagram of the image sensor 400 of the device in ​ . The image sensor 400 can be a camera with a suitable field of view (FOV) so that all features (including identification codes, marks, or other features) on the side of the wafer cassette 200 (refer to ​ ) can be clearly detected by the image sensor 400 with a suitable resolution. For example, the FOV height (also referred to as the vertical FOV) H1 of the image sensor 400 should be greater than the height of the wafer cassette 200 (refer to ​ ), and the FOV width (also referred to as the horizontal FOV) W1 of the image sensor 400 should be greater than the width of the wafer cassette 200 (refer to

[0109] ​ is a flowchart of a method M1' for processing a wafer cassette according to some embodiments of the present disclosure. Refer to ​ and ​ . The method M1' can include steps S01, S02, S1', and ​ the steps S2 to S10 of the method M1 shown in ​ . At step S01, the wafer cassette is moved to the identification position of the processing device by using a robotic arm. At step S02, the type of the wafer cassette is identified. At step S1', according to the type of the wafer cassette, the wafer cassette is moved to one of two different rotary tables by using a robotic arm. It should be understood that additional steps can be provided before, during, and after the steps S01 to S1' shown in , and for additional embodiments of the method, some of the following steps S1 to S10 can be replaced or eliminated. The order of operations / processes can be interchanged.

[0110] Method M1' starts at step S01, where the wafer cassette 200 is moved to the identification position of the processing device 100 by using the robotic arm RM. As described above, the image sensor 400 can detect information about the identification code, mark, or feature of the wafer cassette 200. For example, the top side and four lateral sides of the wafer cassette 200 are detected.

[0111] Method M1' proceeds to step S02, where the type of the wafer cassette 200 is identified. As described above, the controller CR can receive the detected information (e.g., an image) from the image sensor 400 and determine the type of the wafer cassette 200 based on the detected information. There can be two types of wafer cassettes 200, such as the first type of wafer cassette 200A and the second type of wafer cassette 200B described above.

[0112] Method M1' proceeds to step S1', where the wafer cassette 200 is moved to one of two different turntables 120A and 120B by using the robotic arm RM according to the type of the wafer cassette 200. For example, if the wafer cassette 200 is determined to be the first type of wafer cassette 200A, the robotic arm RM moves it to the turntable 120A. Conversely, if the wafer cassette 200 is determined to be the second type of wafer cassette 200B, the robotic arm RM moves it to the turntable 120B. After moving the wafer cassette 200 to one of the two different turntables 120A and 120B, method M1' proceeds to ​ steps S2 - S10 of the method M1 shown. Other details of this embodiment are similar to those described above and are therefore not repeated here.

[0113] Based on the above discussion, it can be seen that the present disclosure provides advantages. However, it should be understood that other embodiments may provide additional advantages, not all advantages must be disclosed herein, and no specific advantage is required for all embodiments. One advantage is that the wafer cassette is opened and closed by the cassette handling device, so that the opening / closing speed of the wafer cassette can match the speed of the robotic arm, thereby improving efficiency and reducing the risk of interaction between humans and robots. Another advantage is that the cassette handling device is equipped with an optical inspection device for checking the attachment integrity between the sealing strip and the cassette, and an alarm event occurs when the inspection result indicates that the attachment integrity is unacceptable. A maintenance process can be performed to restore the sealing strip to its initial position when the alarm event occurs.

[0114] According to some embodiments of the present disclosure, a method for processing a wafer cassette includes placing the wafer cassette on a stage; opening the wafer cassette such that a sealing strip of the wafer cassette is exposed; guiding a light beam above the sealing strip; determining whether the light beam is blocked by the sealing strip; and in response to determining that the light beam is blocked by the sealing strip, performing a maintenance process on the sealing strip.

[0115] In some embodiments, the light beam propagates along a horizontal path above the sealing strip that is higher than at least a portion of a top surface of the sealing strip.

[0116] In some embodiments, the light beam propagates along a horizontal path above the sealing strip that is substantially parallel to a top surface of the stage.

[0117] In some embodiments, the wafer cassette has a first side directly below the light beam, and when viewed from the top, a path of the light beam above the sealing strip is substantially parallel to the first side of the wafer cassette.

[0118] In some embodiments, the method further includes rotating the wafer cassette such that a second side of the wafer cassette rotates to a position directly below the light beam.

[0119] In some embodiments, after rotating the wafer cassette, when viewed from the top, the path of the light beam is substantially parallel to the second side of the wafer cassette.

[0120] In some embodiments, the maintenance process includes the step of adjusting a position of the sealing strip such that the light beam is not blocked by the sealing strip.

[0121] In some embodiments, the step of opening the wafer cassette includes the step of separating a lid of the wafer cassette from a housing of the wafer cassette, wherein the sealing strip is above the housing of the wafer cassette.

[0122] In some embodiments, the method further includes the step of closing the wafer cassette in response to determining that the light beam is not blocked by the sealing strip.

[0123] According to some embodiments of the present disclosure, a method for processing a wafer cassette includes opening the wafer cassette by using a clamping mechanism; determining whether a sealing strip is detached from a lug on a first side of the wafer cassette; and in response to determining that the sealing strip is detached from the lug on the first side of the wafer cassette, performing a first maintenance process on the sealing strip.

[0124] In some embodiments, the method further includes identifying a type of a wafer cassette; and placing the wafer cassette on one of a plurality of stages according to the identified type of the wafer cassette, wherein the step of opening the wafer cassette is performed on the one of the stages.

[0125] In some embodiments, the first maintenance process includes the step of reducing a gap between the sealing strip of the wafer cassette and the lug on the first side.

[0126] In some embodiments, the method further includes closing the wafer cassette by using the clamping mechanism in response to determining that the sealing strip has not detached from the lug on the first side of the wafer cassette.

[0127] In some embodiments, the method further includes determining whether the sealing strip has detached from a lug on a second side of the wafer cassette; and performing a second maintenance process on the sealing strip in response to determining that the sealing strip has detached from the lug on the second side of the wafer cassette.

[0128] In some embodiments, the method further includes rotating the wafer cassette before determining whether the sealing strip has detached from the lug on the second side of the wafer cassette.

[0129] According to some embodiments of the present disclosure, an apparatus for processing a wafer cassette includes a first stage, a first clamping mechanism, and a first optical inspection device. The first stage is configured to support the wafer cassette. The first clamping mechanism is above the first stage and is configured to clamp and move a lid of the wafer cassette. The first optical inspection device is above the first stage, wherein the first optical inspection device includes a light emitter configured to generate a light beam and a light sensor configured to receive the light beam, and wherein the path of the light beam overlaps the first stage when viewed from the top.

[0130] In some embodiments, a path of the light beam is substantially parallel to a top surface of the first stage.

[0131] In some embodiments, the light beam is a laser beam.

[0132] In some embodiments, the apparatus further includes a second stage; a second clamping mechanism above the second stage; and a second optical inspection device above the second stage, wherein the first optical inspection device and the second optical inspection device are at different levels.

[0133] In some embodiments, the apparatus further includes an image sensor configured to detect the wafer cassette; a controller configured to identify a type of the wafer cassette according to a detection result of the image sensor; and a robotic arm configured to move the wafer cassette to one of the first stage and the second stage according to the type of the wafer cassette.

[0134] The foregoing describes the features of several embodiments, enabling those skilled in the art to better understand aspects of the present disclosure. Those skilled in the art should understand that they can readily use the present disclosure as a basis for designing or modifying other processes and structures for the same purposes and / or achieving the same advantages as those introduced herein. Those skilled in the art should also recognize that such equivalent structures do not depart from the spirit and scope of the present disclosure, and such equivalent structures can be variously changed, substituted, and replaced herein without departing from the spirit and scope of the present disclosure.

Claims

1. A method for processing a wafer storage cassette, characterized in that, It includes the following steps: Place a wafer cassette onto a stage; Open the wafer cassette such that a sealing strip of the wafer cassette is exposed; Direct a light beam above the sealing strip; Determine whether the light beam is blocked by the sealing strip; and In response to determining that the light beam is blocked by the sealing strip, perform a maintenance process on the sealing strip.

2. The method according to claim 1, wherein Wherein the light beam propagates along a horizontal path above the sealing strip that is higher than at least a portion of a top surface of the sealing strip.

3. The method according to claim 1, characterized in that, Wherein the light beam propagates along a horizontal path above the sealing strip that is substantially parallel to a top surface of the stage.

4. The method according to claim 1, characterized in that, Wherein the wafer cassette has a first side directly below the light beam, and when viewed from the top, a path of the light beam above the sealing strip is substantially parallel to the first side of the wafer cassette.

5. The method according to claim 4, characterized in that, Further includes the following steps: Rotate the wafer cassette such that a second side of the wafer cassette rotates to a position directly below the light beam.

6. A method for processing a wafer storage cassette, characterized in that, Includes the following steps: Open a wafer cassette by using a clamping mechanism; Determine whether a sealing strip detaches from a lug on a first side of the wafer cassette; and In response to determining that the sealing strip detaches from the lug on the first side of the wafer cassette, perform a first maintenance process on the sealing strip.

7. The method according to claim 6, wherein Further includes the following steps: Identify a type of a wafer cassette; and Place the wafer cassette onto one of a plurality of stages according to the identified type of the wafer cassette, wherein the step of opening the wafer cassette is performed on the one of the stages.

8. An apparatus for processing a wafer cassette, characterized in that, Includes: A first stage for supporting a wafer cassette; A first clamping mechanism above the first stage for clamping and moving a cover of the wafer cassette; And A first optical inspection device above the first stage, wherein the first optical inspection device includes a light emitter for generating a light beam and a light sensor for receiving the light beam, and when viewed from the top, a path of the light beam overlaps with the first stage.

9. The device according to claim 8, wherein, Wherein a path of the light beam is substantially parallel to a top surface of the first stage.

10. The device according to claim 8, characterized in that, Wherein the light beam is a laser beam.

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