Warped wafer transmission method and warped wafer transmission device

Abstract

The invention provides a warped wafer transmission method and device, and the method comprises the steps: taking out a warped wafer from a first groove of a material box through a Bernoulli arm, and transferring the warped wafer to a SUBCHUCK device; the Bernoulli arm is utilized to transfer the warped wafer subjected to the pre-alignment operation to a pre-calibrated wafer loading position W2, a working disc is vertically moved to a pre-calibrated wafer handover height H1, working disc vacuum is started, Bernoulli arm blowing is stopped, and the warped wafer falls on the working disc; and horizontally moving the working disc to a pre-calibrated auxiliary blowing position W3, and starting an auxiliary blowing system positioned above the warped wafer, so that the warped wafer is uniformly adsorbed onto the working disc. According to the transmission method and device provided by the invention, the transmission efficiency of the warped wafer can be improved.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor technology, and more particularly, to a method and apparatus for warped wafer transfer. Background Art

[0002] During the semiconductor manufacturing process, wafers often bend or deform (i.e., warp) on their surfaces due to reasons such as non-uniform stress, mismatched thermal expansion coefficients, and overly thin wafer thickness. Warped wafers pose great challenges to the transfer and adsorption during probe station testing. Traditional wafer transfer methods cannot stably adsorb warped wafers, thus making it impossible to smoothly transfer them. Moreover, during the transfer process, the wafers are prone to falling off or being damaged.

[0003] Therefore, there is an urgent need for a method and apparatus that can adapt to the deformation characteristics of warped wafers and achieve reliable wafer transfer, so as to solve problems such as poor adsorption and high wafer breakage rate of warped wafers during automatic transfer in the prior art. Summary of the Invention

[0004] The purpose of the present disclosure is to provide a method and apparatus for warped wafer transfer to solve the problems of poor adsorption and high wafer breakage rate of wafers with curved or deformed surfaces during the transfer process.

[0005] In a first aspect, an embodiment of the present disclosure provides a method for warped wafer transfer, including the following steps:

[0006] Using a Bernoulli arm to pick up a warped wafer from a first slot of a cassette and transfer it to a SUBCHUCK device, which is configured to perform a pre-alignment operation on the warped wafer;

[0007] Using the Bernoulli arm to transfer the warped wafer that has undergone the pre-alignment operation to a pre-calibrated wafer loading position W2, vertically moving a work plate to a pre-calibrated wafer handover height H1, turning on the vacuum of the work plate, and turning off the blowing of the Bernoulli arm to make the warped wafer fall onto the work plate; and

[0008] Horizontally moving the work plate to a pre-calibrated auxiliary blowing position W3, and turning on an auxiliary blowing system located above the warped wafer to evenly adsorb the warped wafer onto the work plate.

[0009] Optionally, in the step of using a Bernoulli arm to pick up a warped wafer from a first slot of a cassette and transfer it to a SUBCHUCK device, the step of using a Bernoulli arm to pick up a warped wafer from a first slot of a cassette includes:

[0010] Placing the Bernoulli arm at a pre-calibrated wafer picking position W1;

[0011] Vertically move down the Bernoulli arm by a pre-calibrated lifting distance Δh, and turn on the Bernoulli arm to blow air to adsorb the warped wafer; and

[0012] Vertically move up the Bernoulli arm by the lifting distance Δh, and horizontally move the Bernoulli arm to move the warped wafer out of the first slot.

[0013] Optionally, in the step of using the Bernoulli arm to take out the warped wafer from the first slot of the cassette, the calibration method of the wafer taking position W1 is as follows:

[0014] Horizontally rotate the Bernoulli arm so that the Bernoulli arm faces the direction of the cassette, wherein a standard wafer is pre-placed in the second slot of the cassette;

[0015] Vertically move the Bernoulli arm so that the upper surface of the Bernoulli arm is at a first preset distance from the lower surface of the standard wafer, wherein the range of the first preset distance is 1 mm to 3 mm;

[0016] Horizontally move the Bernoulli arm so that the Bernoulli arm enters the cassette, and calibrate the position of the Bernoulli arm as the wafer taking position W1.

[0017] Optionally, in the step of using the Bernoulli arm to take out the warped wafer from the first slot of the cassette, the calibration method of the lifting distance Δh is as follows:

[0018] Vertically move down the Bernoulli arm at the wafer taking position W1 so that the lower surface of the Bernoulli arm is at a second preset distance from the highest point of the crystal plane of the warped wafer, wherein the range of the second preset distance is 1 mm to 3 mm;

[0019] Calibrate the downward movement distance of the Bernoulli arm as the lifting distance Δh.

[0020] Optionally, in the step of using the Bernoulli arm to take out the warped wafer from the first slot of the cassette and transfer it to the SUBCHUCK device, the process of transferring to the SUBCHUCK device includes:

[0021] Horizontally move the Bernoulli arm so that the Bernoulli arm is directly above the SUBCHUCK device,

[0022] Vertically move up the SUBCHUCK device, turn on the SUBCHUCK vacuum, and turn off the Bernoulli arm blowing air, so that the warped wafer falls onto the SUBCHUCK device; horizontally rotate the SUBCHUCK device 360°, and mark the height of the SUBCHUCK device at this time as the wafer handover height between the SUBCHUCK and the Bernoulli arm.

[0023] Optionally, the step of using the Bernoulli arm to pick up the warped wafer from the first slot of the cassette and transfer it to the SUBCHUCK device further includes:

[0024] Vertically lower the SUBCHUCK device, control the SUBCHUCK device to drive the warped wafer to rotate horizontally by 360°, and there is no interference between the warped wafer and the surrounding hardware during the rotation; mark the height of the SUBCHUCK device at this time as the pre-alignment height.

[0025] Optionally, in the step of using the Bernoulli arm to transfer the warped wafer that has undergone the pre-alignment operation to the pre-calibrated wafer loading position W2 and vertically moving the worktable to the pre-calibrated wafer transfer height H1, the calibration method of the wafer loading position W2 is as follows:

[0026] Horizontally rotate the Bernoulli arm so that the Bernoulli arm faces the direction of the worktable;

[0027] Vertically move the Bernoulli arm so that the lower surface of the warped wafer is at a third preset distance from the upper surface of the worktable, where the range of the third preset distance is 8 mm to 12 mm;

[0028] Horizontally move the Bernoulli arm so that the warped wafer is concentric with the worktable, and mark the position of the Bernoulli arm as the wafer loading position W2.

[0029] Optionally, in the step of using the Bernoulli arm to transfer the warped wafer that has undergone the pre-alignment operation to the pre-calibrated wafer loading position W2 and vertically moving the worktable to the pre-calibrated wafer transfer height H1, the calibration method of the wafer transfer height H1 is as follows:

[0030] Vertically move the worktable up so that the upper surface of the worktable is at a fourth preset distance from the lower surface of the warped wafer minus the wafer warpage amount, where the range of the fourth preset distance is 1 mm to 3 mm; mark the height of the worktable as the wafer transfer height H1.

[0031] Optionally, in the step of horizontally moving the worktable to the pre-calibrated auxiliary blowing position W3, turning on the auxiliary blowing system above the warped wafer, and uniformly adsorbing the warped wafer to the worktable, the calibration method of the auxiliary blowing position W3 is as follows:

[0032] Horizontally move the worktable so that the center of the worktable is directly below the auxiliary blowing system, and mark the position of the worktable as the auxiliary blowing position W3.

[0033] Second aspect, embodiments of the present disclosure provide a warped wafer transfer device, including:

[0034] a processor; and

[0035] a memory for storing executable instructions of the processor;

[0036] wherein, the processor is configured to execute the method by executing the executable instructions.

[0037] Compared with the related art, embodiments of the present disclosure at least have the following technical effects:

[0038] The warped wafer transfer method and device provided by the present disclosure can effectively ensure the precise docking and uniform adsorption of wafers through the calibration process, especially the calibration of the wafer handover height, loading position, and auxiliary blowing position, and further improve the stability and adsorption uniformity of the wafers by optimizing the surface of the warped wafers using the auxiliary blowing system, thereby significantly improving the transfer accuracy and efficiency of the warped wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the accompanying drawings in the following description are only some embodiments of the present disclosure, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts. In the drawings:

[0040] Figure 1 is a schematic flowchart of a warped wafer transfer method provided by some embodiments of the present disclosure;

[0041] Figure 2 is a schematic structural diagram of some devices involved in the warped wafer transfer method provided by some embodiments of the present disclosure;

[0042] Figure 3 is a schematic structural diagram of some devices involved in the warped wafer transfer method provided by some embodiments of the present disclosure;

[0043] Figure 4 is a schematic structural diagram of some devices involved in the warped wafer transfer method provided by some embodiments of the present disclosure;

[0044] Figure 5 is a schematic structural diagram of some devices involved in the warped wafer transfer method provided by some embodiments of the present disclosure;

[0045] Figure 6 is a schematic structural diagram of a warped wafer transfer device provided by some embodiments of the present disclosure. DETAILED DESCRIPTION

[0046] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to the accompanying drawings. Apparently, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of them. Based on the embodiments of the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0047] The terms used in the embodiments of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The singular forms "a", "the", and "said" used in the embodiments of the present disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. "Plural" generally includes at least two.

[0048] It should be understood that the term "and / or" used herein is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0049] It should be understood that although terms such as first, second, and third may be used in the embodiments of the present disclosure, they should not be limited to these terms. These terms are only used for distinction. For example, without departing from the scope of the embodiments of the present disclosure, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0050] It should also be noted that the term "comprising", "including", or any other variant thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or elements inherent to such commodity or device. Without further limitation, an element defined by the statement "including one" does not exclude the existence of another identical element in the commodity or device including the element.

[0051] As described in the background art, due to problems such as uneven stress, mismatched thermal expansion coefficients, or overly thin thickness in existing wafers, surface bending or deformation is likely to occur, that is, warped wafers are formed.

[0052] Warped wafers typically exhibit the following several typical forms: One form is that the center bulges upward and the edges sink, that is, the middle of the wafer bends upward while the edges are close to the support surface; Another form is that the center is concave and the edges are warped upward, that is, the edges of the wafer are warped upward and the center is close to the support surface; In addition, there are also wafers with asymmetric warping or local deformation, such as only one side edge being warped upward or having local convex regions. The warping amount of the warped wafer (the vertical deviation between the highest point and the lowest point on the wafer surface, which can also be called the warpage degree) can range from dozens of microns to hundreds of microns, and the deformation direction and degree vary greatly between batches, increasing the complexity of automated handling and alignment. Due to the existence of the above warping forms, the wafer often cannot achieve full contact or stable adsorption during transmission, and problems such as adsorption failure, sliding misalignment, and even wafer fragmentation are likely to occur.

[0053] To solve or at least alleviate the above technical problems, in one aspect of the embodiments of the present disclosure, a method for transporting warped wafers is provided, including the following steps:

[0054] S100, Use a Bernoulli arm to pick up the warped wafer from the first slot of the cassette and transfer it to the SUBCHUCK device, which is configured to perform a pre-alignment operation on the warped wafer;

[0055] S200, Use the Bernoulli arm to transfer the warped wafer that has undergone the pre-alignment operation to the pre-calibrated wafer loading position W2, vertically move the worktable to the pre-calibrated wafer transfer height H1, turn on the worktable vacuum, and turn off the Bernoulli arm blowing air, so that the warped wafer falls onto the worktable; And

[0056] S300, Horizontally move the worktable to the pre-calibrated auxiliary blowing position W3, turn on the auxiliary blowing system located above the warped wafer, and make the warped wafer evenly adsorbed onto the worktable.

[0057] It can be seen that the method for transporting warped wafers provided by the present disclosure can effectively ensure the precise docking and uniform adsorption of the wafer through the calibration process, especially the calibration of the wafer transfer height, loading position, and auxiliary blowing position, and further improves the stability and adsorption uniformity of the wafer by optimizing the surface of the warped wafer using the auxiliary blowing system, thereby significantly improving the processing accuracy and efficiency of the warped wafer.

[0058] The following will detail the optional embodiments of the present disclosure with reference to the accompanying drawings.

[0059] Refer to Figures 1 to 5 , Some embodiments of the present disclosure provide a method for transporting warped wafers, including the following steps:

[0060] S100, Use the Bernoulli arm 20 to pick up the warped wafer 60 from the first slot 11 of the cassette 10 and transfer it to the SUBCHUCK device 30, which is configured to perform a pre-alignment operation on the warped wafer.

[0061] In this step, the Bernoulli arm 20 is a device that realizes the adsorption and transportation of objects through air flow control. It adsorbs the warped wafer 60 by generating negative pressure and precisely moves it to the required position. Sensors are usually configured on the Bernoulli arm 20, mainly used to detect the adsorption state of the wafer, such as whether the wafer is correctly adsorbed, whether there are abnormalities, etc. When the sensor detects an abnormal situation, it will send an alarm signal. The Bernoulli arm 20 is usually equipped with an accurate position control system, which can realize precise position adjustment of the wafer. Specifically, in this embodiment, the position control system of the Bernoulli arm 20 includes: a horizontal front-back movement axis (i.e., the horizontal feed axis L2), a vertical up-down movement axis (i.e., the vertical lift axis L3), and a horizontal rotational movement axis (i.e., the rotation axis L5). Through the coordinated control of the L2 axis, L3 axis, and L5 axis, the Bernoulli arm 20 can accurately move the warped wafer 60 from one position to another, ensuring the stability of the warped wafer 60 during the entire transportation process.

[0062] The cassette 10 is a container for storing wafers, usually having multiple slots for convenient access to different wafers. The first slot 11 of the cassette 10 is the first slot for wafer storage, and wafers are usually accessed from the first slot 11 first. In this embodiment, the first slot 11, the second slot 12... the nth slot are arranged in sequence from bottom to top along the vertical direction.

[0063] The SUBCHUCK device 30 (sub-chuck) is a device for supporting and fixing wafers. The SUBCHUCK device 30 can fix the wafer on its surface through vacuum adsorption and can accurately align the wafer, especially when the wafer is transferred from the cassette to the worktable, testing equipment, or other processing equipment. The SUBCHUCK device 30 has a rotation function and can usually rotate 360° to adjust the angle of the wafer or perform self-calibration to ensure the docking accuracy between the wafer and other devices.

[0064] In some embodiments, the process of using the Bernoulli arm 20 to pick up the warped wafer 60 from the first slot 11 of the cassette 10 further includes the following steps:

[0065] S110, Place the Bernoulli arm 20 at the pre-calibrated wafer pick-up position W1.

[0066] Among them, the wafer taking position W1 is the combined position of the Bernoulli arm 20 in the horizontal direction (L2 axis), vertical direction (L3 axis), and rotation angle (L5 axis). After precise calibration, it can ensure that when the Bernoulli arm 20 takes out the wafer, its adsorption surface stably adsorbs the wafer and does not interfere with the slot wall when entering and exiting the cassette 10, thereby realizing the stable adsorption and safe taking out of the wafer.

[0067] As a specific example, the calibration method of the wafer taking position W1 includes the following steps:

[0068] S111, Horizontally rotate the Bernoulli arm 20 so that the Bernoulli arm 20 faces the direction of the cassette 10, where a standard wafer is pre-placed in the second slot 12 of the cassette 10.

[0069] As a specific operation example, control the movement of the rotation axis L5 of the Bernoulli arm 20 so that the front end surface of the Bernoulli arm 20 faces the slot direction of the cassette 10; at this time, a standard wafer is pre-placed in the second slot 12 of the cassette 10 for use as a calibration reference wafer.

[0070] S112, Vertically move the Bernoulli arm 20 so that the upper surface of the Bernoulli arm 20 is at a first preset distance from the lower surface of the standard wafer, where the range of the first preset distance is 1 mm to 3 mm, specifically 2 mm in this embodiment.

[0071] As a specific operation example, control the vertical lifting axis L3 of the Bernoulli arm 30 to move downward so that the upper surface of the Bernoulli arm 20 gradually approaches the lower surface of the standard wafer in the second slot 12. Confirm through a height sensor or mechanical limit method. When the distance between them is the first preset distance, record the position of the vertical lifting axis L3 as the height reference for subsequent wafer taking operations.

[0072] S113, Horizontally move the Bernoulli arm 20 so that the Bernoulli arm 20 enters the cassette 10 and calibrate the position of the Bernoulli arm 20 as the wafer taking position W1.

[0073] As a specific operation example, control the horizontal feed axis L2 to move forward slowly so that the Bernoulli arm 20 extends into the cassette 10 and gradually approaches the standard wafer. To avoid collision between the wafer and the edge of the cassette 10 during the entry and exit of the Bernoulli arm 20, the positions of the L2 axis and L5 axis can be further fine-tuned to ensure that the front end of the Bernoulli arm 20 is centered and there is no interference. After confirming that the entry position is correct, record the positions of the L2, L3, and L5 axes at this time as the wafer taking position W1.

[0074] S120. Vertically lower the Bernoulli arm 20 by a pre-calibrated lifting distance Δh, and turn on the Bernoulli arm to blow air to adsorb the warped wafer 60.

[0075] Among them, the calibration method of the lifting distance Δh is as follows:

[0076] Vertically lower the Bernoulli arm 20 at the wafer picking position W1 so that the lower surface of the Bernoulli arm 20 is at a second preset distance from the highest point of the crystal surface of the warped wafer 60. Among them, the range of the second preset distance is 1 mm to 3 mm, specifically 2 mm in this embodiment, to ensure that the wafer can be stably adsorbed during the adsorption process and there will be no collision or disturbance due to too close a distance. Calibrate the downward displacement distance of the Bernoulli arm 20 as the lifting distance Δh.

[0077] As a specific operation example, first, place the Bernoulli arm 20 at the wafer picking position W1 according to the foregoing steps; then, place a warped wafer 60 in the first slot 11 of the cassette 10; control the L3 axis to slowly descend, and during this process, detect the real-time distance between the lower surface of the Bernoulli arm 20 and the highest point of the crystal surface of the warped wafer 60 through an optical sensor or a height sensor; when the vertical distance between the two is detected to reach 2 mm, record the downward displacement distance of the L3 axis at this time and calibrate it as the lifting distance Δh; this calibrated Δh value can be used in subsequent batch material picking to achieve stable adsorption and extraction of different warped wafers.

[0078] S130. Vertically raise the Bernoulli arm 20 by a distance of the lifting distance Δh, and horizontally move the Bernoulli arm 20 to move the warped wafer 60 out of the first slot 11.

[0079] Among them, in the process of vertically raising, control the vertical lifting axis L3 of the Bernoulli arm 20 to move upward, and the displacement amount is the same as the lifting distance Δh in the previous step S120. This operation is used to lift the adsorbed warped wafer 60 out of the slot and leave a safety gap for the subsequent horizontal removal to prevent the edge of the warped wafer 60 from interfering with the slot wall of the cassette 10. Subsequently, control the horizontal feed axis L2 of the Bernoulli arm 10 to move backward, so that the Bernoulli arm 20 adsorbing the wafer is smoothly withdrawn from the first slot 11 of the cassette 10.

[0080] As a specific operation example, after completing the adsorption operation and calibrating the lifting distance Δh, control the L3 axis to move vertically upward by a distance of Δh, so that the Bernoulli arm 20 together with the adsorbed warped wafer 60 rises to a safe height away from the slot wall; then, control the L2 axis to move smoothly in the horizontal reverse direction, so that the Bernoulli arm 20 slowly exits the cassette 10.

[0081] After the above operations are completed, the Bernoulli arm 20 successfully removes the warped wafer 60 from the first slot 11 and is ready to be transferred to the SUBCHUCK device 30 or other target positions for subsequent processing.

[0082] Specifically, the process of transferring to the SUBCHUCK device 30 includes:

[0083] S140, horizontally move the Bernoulli arm 20 so that the Bernoulli arm 20 is directly above the SUBCHUCK device 30.

[0084] In this step, by controlling the coordinated movement of the horizontal feed axis L2 axis and the rotation axis L5 axis of the Bernoulli arm 20, the Bernoulli arm 20 is transferred from the cassette area to directly above the SUBCHUCK device 30.

[0085] S150, vertically move up the SUBCHUCK device 30, turn on the SUBCHUCK vacuum, turn off the blowing of the Bernoulli arm, so that the warped wafer 60 falls onto the SUBCHUCK device 30; horizontally rotate the SUBCHUCK device 360°, and mark the height of the SUBCHUCK device 30 at this time as the wafer handover height between the SUBCHUCK and the Bernoulli arm.

[0086] In this step, the SUBCHUCK device 30 undertakes the function of receiving and pre-aligning the warped wafer 60 from the Bernoulli arm 20. First, control the vertical lifting axis (L6 axis) of the SUBCHUCK device 60 to move upward so that it gradually approaches the bottom surface of the warped wafer 60; in the state where the two are close but not in contact, turn on the SUBCHUCK vacuum adsorption system and turn off the blowing system of the Bernoulli arm 20. At this time, due to the release of the Bernoulli adsorption force, the warped wafer 60 falls smoothly onto the upper surface of the SUBCHUCK device 30 under the action of gravity and the downward vacuum suction force.

[0087] To verify that the warped wafer 60 has been safely placed on the chuck and ensure its stable position, further control the SUBCHUCK device 30 to perform a 360° horizontal rotation. During the rotation process, the system monitors the wafer adsorption state sensor on the Bernoulli arm 20. If the warped wafer 60 has successfully detached from the surface of the Bernoulli arm 2, the sensor should no longer be triggered, thereby confirming that the warped wafer 60 has completed the handover.

[0088] In some embodiments, after using the Bernoulli arm 20 to transfer the warped wafer 60 from the cassette to the SUBCHUCK device 30 to complete the wafer handover, the following steps are further included:

[0089] Vertically move down the SUBCHUCK device 30, control the SUBCHUCK device 30 to drive the warped wafer 60 to rotate horizontally by 360°, and there is no interference between the warped wafer 60 and the surrounding hardware during the rotation; mark the height of the SUBCHUCK device 30 at this time as the pre-alignment height, which is used as the reference height for subsequent wafer angle correction, offset detection and precise positioning.

[0090] S200, use the Bernoulli arm 20 to transfer the warped wafer 60 that has performed the pre-alignment operation to the pre-calibrated wafer loading position W2, vertically move the worktable 40 to the pre-calibrated wafer transfer height H1, turn on the vacuum of the worktable, and turn off the blowing of the Bernoulli arm, so that the warped wafer 60 falls onto the worktable 40.

[0091] In this step, the worktable 40 includes a plurality of control axes for controlling its position and attitude. Among them, the P2 axis is the vertical lifting axis of the worktable 40, which is used to adjust the height of the worktable 40 in the vertical direction, and the P5 axis is the horizontal X axis of the worktable 40, which is used to control the forward and backward movement of the worktable in the horizontal direction. The P6 axis is the horizontal Y axis of the worktable 40, which cooperates with the P5 axis to ensure the left and right movement of the worktable in the horizontal direction.

[0092] The calibration method of the wafer loading position W2 specifically includes:

[0093] S210, horizontally rotate the Bernoulli arm 20 so that the direction of the Bernoulli arm 20 faces the worktable 40.

[0094] As a specific operation example, control the rotation axis L5 of the Bernoulli arm 20 so that the front of the Bernoulli arm 20 faces the worktable 40.

[0095] S220, vertically move the Bernoulli arm 20 so that the lower surface of the warped wafer 60 is at a third preset distance from the upper surface of the worktable 40, where the range of the third preset distance is 8 mm to 12 mm, and specifically it can be 10 mm in this embodiment.

[0096] This step can make the Bernoulli arm 20 carry the warped wafer 60 to align with the loading position of the worktable 40 while maintaining a safe vertical gap, so as to provide a height reference for the subsequent setting of the transfer height H1.

[0097] As a specific operation example, after completing the horizontal rotation positioning described in S210, control the vertical lifting axis L3 of the Bernoulli arm 20 to slowly lower; judge the vertical distance between the lower surface of the warped wafer 60 and the upper surface of the worktable 40 through a height sensor or displacement calculation inside the controller; when this vertical distance reaches 10 mm, stop the descent of the L3 axis; at this time, a safe gap is maintained between the Bernoulli arm 20 and the worktable 40.

[0098] S230, horizontally move the Bernoulli arm 20 to make the warped wafer 60 concentric with the worktable 40, and calibrate the position of the Bernoulli arm 20 as the loaded wafer position W2.

[0099] In this step, by controlling the horizontal position of the Bernoulli arm 20, the geometric center of the warped wafer 60 is made to coincide with the center of the worktable 40, so as to ensure the placement concentricity and vacuum adsorption accuracy during the subsequent wafer dropping process.

[0100] As a specific operation example, after completing the vertical positioning described in S220, control the horizontal advance and retreat axis L2 of the Bernoulli arm 20 to move forward. The image recognition module can be called to obtain the deviation information between the edge contour of the current warped wafer 60 and the edge of the worktable 40, calculate its center offset amount, and drive the L2 axis to achieve adjustment according to the offset result. After the adjustment is completed, the center of the warped wafer 60 basically coincides with the center of the worktable 40. Record the combined position of the Bernoulli arm 20 on the L2, L3, and L5 axes at this time, and calibrate it as the loaded wafer position W2.

[0101] The calibration method for the wafer transfer height H1 is as follows: vertically move up the worktable 40 so that the upper surface of the worktable 40 is at a fourth preset distance from the lower surface of the warped wafer 60 minus the wafer warpage amount. Among them, the range of the fourth preset distance is 1 mm to 3 mm, and specifically in this embodiment, it can be 2 mm. Calibrate the height of the worktable 40 as the wafer transfer height H1.

[0102] As a specific operation example, after the Bernoulli arm 20 aligns the warped wafer 60 with the center of the worktable 40 and maintains a vertical spacing in the previous step S230, keep the position of the Bernoulli arm 20 unchanged; control the vertical lifting axis P2 of the worktable 40 to slowly rise; at the same time, measure the vertical distance between the upper surface of the worktable 40 and the lowest point of the crystal surface of the lower surface of the warped wafer 60 through a height sensor, a laser ranging system or a built-in encoder, etc.; when it is detected that this distance reaches 2 mm, immediately stop the rise of the P2 axis; record the vertical height of the worktable 40 on the P2 axis at this time, and use this height as the wafer transfer height H1 in subsequent operations.

[0103] Setting the wafer transfer height H1 can ensure that after the wafer is desorbed by the blowing of the Bernoulli arm 20, it can naturally and stably fall onto the surface of the worktable 40, avoiding dropping impacts caused by excessive height and also avoiding premature contact between the wafer and the platen surface or interference with the adsorption system due to too small a height. This calibration method is applicable to the batch processing of wafers with various degrees of warpage.

[0104] S300, horizontally move the worktable 40 to the pre-calibrated auxiliary blowing position W3, and turn on the auxiliary blowing system 50 located above the warped wafer 60 to evenly adsorb the warped wafer onto the worktable 40.

[0105] In this step, the auxiliary blowing system 50 is a directional air flow device installed above the worktable 40, which can generate an air flow from top to bottom after the wafer just lands on the platen, overcoming the warpage tension of the wafer and enabling the warped part to quickly and evenly fit on the adsorption surface of the worktable 40. The auxiliary blowing system 50 may include structures such as an air outlet channel connecting to the air source system, a porous annular air outlet head or an air outlet nozzle, and an adjustable pressure air outlet valve.

[0106] The auxiliary blowing position W3 is the position where the worktable 40 is horizontally moved to align directly below the air outlet of the auxiliary blowing system 50. This position is pre-calibrated to ensure that the auxiliary blowing air flow acts vertically on the upper surface area of the warped wafer 60, thereby prompting the warped part of the warped wafer 60d to gradually adhere to the surface of the worktable 40 and improving the adsorption uniformity and stability.

[0107] The calibration method for the auxiliary blowing position W3 is: horizontally move the worktable 40 so that the center of the worktable 40 is directly below the auxiliary blowing system 50, and calibrate the position of the worktable 40 as the auxiliary blowing position W3.

[0108] As a specific operation example, after the wafer transfer is completed, control the P5 axis and P6 axis of the worktable 40 to move along a preset trajectory, so that the entire worktable 40 moves to a position directly below the auxiliary blowing system 50; after reaching directly below the auxiliary blowing system 50, confirm that the center of the current worktable 40 is aligned with the center of the auxiliary blowing system 50, and the worktable 40 completely enters the auxiliary blowing area; control the auxiliary blowing system 50 to open the air outlet valve and start releasing a vertical air flow at a set pressure (for example, 0.05 - 0.1 MPa), and the duration can be 1 - 10 seconds; under the action of the air flow, the warped part of the warped wafer 60 adheres downward, and when it is feedback that the wafer has completely adhered, turn off the auxiliary blowing system 50. At this time, the warped wafer 60 is evenly and firmly adsorbed on the worktable 40, and the loading is completed.

[0109] The coordinated cooperation between the working disk 40 and the auxiliary blowing system 50 provides a non-contact flattening means for the warped wafer 60, which is particularly suitable for avoiding manual intervention in an automated scenario and improving the surface quality of the wafer.

[0110] Compared with the prior art, the warped wafer transfer method provided by the present disclosure can effectively ensure the precise docking and uniform adsorption of the wafer through the calibration process, especially the calibration of the wafer handover height, loading position, and auxiliary blowing position. Moreover, by optimizing the surface of the warped wafer using the auxiliary blowing system, the stability and adsorption uniformity of the wafer are further improved, thereby significantly enhancing the processing accuracy and efficiency of the warped wafer.

[0111] As Figure 6 shown, in one aspect of the embodiments of the present disclosure, a warped wafer transfer device is provided. The device includes: at least one processor; and a memory communicatively connected to the at least one processor. Wherein, the memory stores instructions executable by the one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method steps as described in the above embodiments.

[0112] The embodiments of the present disclosure provide a non-volatile computer storage medium that stores computer-executable instructions, and the computer-executable instructions can execute the method steps as described in the above embodiments.

[0113] The transfer device may include a processing device (such as a central processing unit) 401, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 402 or the program loaded from the storage device 408 into the random access memory (RAM) 403. In the RAM 403, various programs and data required for the operation of the transfer device are also stored. The processing device 401, the ROM 402, and the RAM 403 are connected to each other through a bus 404. The input / output (I / O) interface 405 is also connected to the bus 404.

[0114] Generally, the following devices can be connected to the I / O interface 406: an input device 406 including, for example, a touch screen, a touchpad, a keyboard, a mouse, a camera, a microphone, etc.; an output device 407 including, for example, a liquid crystal display (LCD), a speaker, etc.; a storage device 408 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 409.

[0115] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. For the systems or devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method part.

[0116] The above embodiments are only used to illustrate the technical solutions of the present disclosure, not to limit them. Although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present disclosure.

Claims

1. A warped wafer transfer method, characterized in that, Including the following steps: Using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette and transfer it to a SUBCHUCK device, which is configured to perform a pre-alignment operation on the warped wafer; Using the Bernoulli arm to transfer the warped wafer that has undergone the pre-alignment operation to a pre-calibrated wafer loading position W2, vertically moving the worktable to a pre-calibrated wafer transfer height H1, turning on the worktable vacuum, and turning off the Bernoulli arm blowing air, so that the warped wafer falls onto the worktable; And Horizontally moving the worktable to a pre-calibrated auxiliary blowing position W3, turning on an auxiliary blowing system located above the warped wafer, so that the warped wafer is evenly adsorbed onto the worktable.

2. The warped wafer transfer method according to claim 1, wherein In the step of using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette and transfer it to a SUBCHUCK device, the step of using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette includes: Placing the Bernoulli arm at a pre-calibrated wafer picking position W1; Vertically moving down the Bernoulli arm by a pre-calibrated lifting distance Δh, turning on the Bernoulli arm to blow air to adsorb the warped wafer; and Vertically moving up the Bernoulli arm by the lifting distance Δh, horizontally moving the Bernoulli arm, and moving the warped wafer out of the first slot.

3. The warped wafer transfer method according to claim 2, wherein In the step of using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette, the calibration method of the wafer picking position W1 is: Horizontally rotating the Bernoulli arm so that the Bernoulli arm faces the direction of the cassette, wherein a standard wafer is pre-placed in the second slot of the cassette; Vertically moving the Bernoulli arm so that the upper surface of the Bernoulli arm is at a first preset distance from the lower surface of the standard wafer, wherein the range of the first preset distance is 1 mm to 3 mm; Horizontally moving the Bernoulli arm so that the Bernoulli arm enters the cassette, and calibrating the position of the Bernoulli arm as the wafer picking position W1.

4. The warped wafer transfer method according to claim 3, wherein, In the step of using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette, the calibration method of the lifting distance Δh is: Vertically moving down the Bernoulli arm at the wafer picking position W1 so that the lower surface of the Bernoulli arm is at a second preset distance from the highest point of the crystal surface of the warped wafer, wherein the range of the second preset distance is 1 mm to 3 mm; Calibrating the downward movement distance of the Bernoulli arm as the lifting distance Δh.

5. The warped wafer transfer method according to claim 1, wherein In the step of using a Bernoulli arm to pick up a warped wafer from the first slot of a cassette and transfer it to a SUBCHUCK device, the process of transferring it to the SUBCHUCK device includes: Horizontally moving the Bernoulli arm so that the Bernoulli arm is directly above the SUBCHUCK device, Vertically move the SUBCHUCK device upward, turn on the SUBCHUCK vacuum, and turn off the blowing of the Bernoulli arm, so that the warped wafer falls onto the SUBCHUCK device; Horizontally rotate the SUBCHUCK device by 360°, and mark the height of the SUBCHUCK device at this time as the wafer transfer height between the SUBCHUCK and the Bernoulli arm.

6. The warped wafer transfer method according to claim 5, characterized in that, The step of using the Bernoulli arm to pick up the warped wafer from the first slot of the cassette and transfer it to the SUBCHUCK device further includes: Vertically move the SUBCHUCK device downward, control the SUBCHUCK device to drive the warped wafer to rotate horizontally by 360°, and there is no interference between the warped wafer and the surrounding hardware during the rotation; Mark the height of the SUBCHUCK device at this time as the pre-alignment height.

7. The warped wafer transfer method according to claim 1, wherein In the step of using the Bernoulli arm to transfer the warped wafer that has performed the pre-alignment operation to the pre-calibrated wafer loading position W2 and vertically moving the worktable to the pre-calibrated wafer transfer height H1, the calibration method of the wafer loading position W2 is: Horizontally rotate the Bernoulli arm so that the Bernoulli arm faces the direction of the worktable; Vertically move the Bernoulli arm so that the lower surface of the warped wafer is at a third preset distance from the upper surface of the worktable, where the range of the third preset distance is 8 mm to 12 mm; Horizontally move the Bernoulli arm so that the warped wafer is concentric with the worktable, and mark the position of the Bernoulli arm as the wafer loading position W2.

8. The warped wafer transfer method according to claim 7, wherein In the step of using the Bernoulli arm to transfer the warped wafer that has performed the pre-alignment operation to the pre-calibrated wafer loading position W2 and vertically moving the worktable to the pre-calibrated wafer transfer height H1, the calibration method of the wafer transfer height H1 is: Vertically move the worktable upward so that the upper surface of the worktable is at a fourth preset distance from the lower surface of the warped wafer minus the wafer warp amount, where the range of the fourth preset distance is 1 mm to 3 mm; Mark the height of the worktable as the wafer transfer height H1.

9. The warped wafer transfer method according to claim 1, wherein In the step of horizontally moving the worktable to the pre-calibrated auxiliary blowing position W3 and turning on the auxiliary blowing system above the warped wafer to evenly adsorb the warped wafer onto the worktable, the calibration method of the auxiliary blowing position W3 is: Horizontally move the worktable so that the center of the worktable is directly below the auxiliary blowing system, and mark the position of the worktable as the auxiliary blowing position W3.

10. A warped wafer transfer device, characterized in that, Includes: A processor; And A memory for storing the executable instructions of the processor; Wherein, the processor is configured to execute the method according to any one of claims 1-9 by executing the executable instructions.

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