Wafer flipping device, wafer flipping method, and wafer processing apparatus

Abstract

The application discloses a wafer overturning device, a wafer overturning method and a wafer processing equipment, and belongs to the field of advanced process wafer processing technology. The technical problem of random wafer overturning direction, easy falling damage and lower limit part easy to wear and cause wafer sliding to be out of position is solved. The wafer overturning device comprises a base, a bracket rotatably connected to the base and a flexible claw swingably arranged on the bracket, and an upper limit part and a lower limit part made of hard wear-resistant and impact-resistant material are arranged on the bracket. The flexible claw supports the wafer with abnormal wafer overturning direction, effectively solving the problems of random wafer overturning direction and easy wafer falling in the wafer transmission process. On this basis, the material of the lower limit part is set to reduce the wear of the lower limit part, prevent the wafer edge from being stuck by the pits or scratches on the lower limit part, and the angle of the guide slope surface is set to guide the wafer to overturn to the bracket, thereby solving the problem of wafer sliding to be out of position in the horizontal state of the wafer with rough edges.

Description

Technical Field

[0001] This application belongs to the field of advanced process wafer processing technology, and more specifically, relates to wafer flipping apparatus, wafer flipping method and wafer processing equipment. Background Technology

[0002] Chemical mechanical polishing (CMP) equipment is currently the equipment used to achieve global planarization of the semiconductor wafer surface, and it is one of the five core processes in wafer manufacturing. A CMP system generally includes a front-end module, a polishing unit, a cleaning unit, and a drying unit, thereby achieving "dry in, dry out" wafers and obtaining wafers with surface uniformity that meets process requirements.

[0003] In vertical cleaning and drying systems, wafers need to be flipped from a vertical position to a horizontal position before being picked up by the EFEM robot. In existing CMP cleaning and drying units, wafers are usually spun dry, then picked up by a robot and placed on a tray, before being picked up by the EFEM robot in a horizontal position. Summary of the Invention

[0004] To address the aforementioned problems, this application provides a wafer flipping device, a wafer flipping method, and a wafer processing equipment, thereby solving the problem that wafers with rough and sharp edges are prone to flipping during the transfer process.

[0005] A first aspect of this application provides a wafer flipping apparatus, comprising:

[0006] Base;

[0007] A bracket, rotatably mounted on the base, is used to rotate the wafer to a horizontal position. The bracket is provided with an upper limit member and a lower limit member. The lower limit member is a wear-resistant and impact-resistant hard material component. The lower limit member has a guide slope with an inclination angle of 15° to 35°.

[0008] The swivel claw is mounted on the upper part of the bracket;

[0009] When the bracket is in a vertical position, the claw is configured to swing vertically to the outside of the top edge of the wafer to receive the wafer and provide limiting support for the top edge of the wafer.

[0010] When the tray is in a horizontal position, the claw is configured to swing vertically and move away from the wafer to avoid the wafer to be removed.

[0011] In one embodiment, the lower limiting member is made of PEEK or alumina ceramic.

[0012] In one embodiment, the inner side of the claw has a first slope and a second slope located on the side of the first slope away from the bracket, the angle between the first slope and the second slope is an obtuse angle, and the junction of the first slope and the second slope forms a first limiting point;

[0013] When the bracket is in a vertical position, the first limiting position is used to abut against the outer side of the top edge of the wafer.

[0014] In one embodiment, the claw further has a third slope that is in contact with the second slope. The third slope is located on the side of the second slope away from the first slope and forms an obtuse angle with the second slope. The junction of the second slope and the third slope forms a second limiting point.

[0015] When the carrier is in a vertical position and the wafer slides outward and downward along the guide slope during the wafer flipping process away from the carrier, the second limiting point is used to abut against the outer edge of the top edge of the wafer.

[0016] In one embodiment, the first limiting point and the second limiting point are configured to control the tilt angle of the wafer after flipping within an angle β, where the angle β is 2~3°, so as to reduce the impact force between the wafer and the upper limiting member when the wafer is flipped to a horizontal state and to prevent the wafer from detaching from the upper limiting member.

[0017] In one embodiment, there are two upper limit stop members and two lower limit stop members, which are arranged horizontally and symmetrically, and the claw is disposed between the two upper limit stop members.

[0018] In one embodiment, when the bracket is in a vertical state and the claw is in a limiting support state, the highest point of the inner side of the claw is higher than the highest point of the wafer, and the height difference between the two is h1.

[0019] The height difference between the middle position of the guide slope in the direction of inclination and the highest position of the guide slope is h2;

[0020] The difference between h1 and h2 is between 3mm and 5mm, which is used to avoid collision between the claw and the top of the wafer when the claw swings inward.

[0021] In one embodiment, the bracket is further provided with a wafer in-situ detection component for detecting the wafer's in-situ status and a claw drive mechanism for driving the claw to swing. The wafer in-situ detection component is electrically connected to a controller, which is electrically connected to the claw drive mechanism. The wafer in-situ detection component is used to identify the wafer's position information and send the position information to the controller. The controller is used to generate control commands and send them to the claw drive mechanism to control the movement of the claw.

[0022] In one embodiment, the claw drive mechanism includes:

[0023] A telescopic actuator is mounted on the bracket;

[0024] A transmission block is disposed at the output end of the telescopic actuator and is used to slide radially along the bracket under the drive of the telescopic actuator;

[0025] The swing arm is hinged at one end to the transmission block and at the other end to the flexure.

[0026] The telescopic actuator is configured to drive the transmission block to slide radially, thereby causing the pawl to swing via the rocker arm.

[0027] In one embodiment, the controller is used to control the carrier to achieve wafer flipping, and the controller is specifically used to perform the following steps:

[0028] When the flipping angle is less than the first angle, the bracket is controlled to flip at a uniform acceleration.

[0029] When the flipping angle is not less than the first angle and less than the second angle, the bracket is controlled to flip at a constant speed.

[0030] When the flipping angle is greater than the second angle, the bracket is controlled to flip with uniform deceleration;

[0031] During the overturning process, the maximum safe angular acceleration of the overturning is negatively correlated with the inclination angle of the guide slope.

[0032] A second aspect of this application provides a wafer flipping apparatus, including:

[0033] The base, shaped like an L, includes a horizontal base plate and vertical side plates to prevent wafer debris contaminants from splashing.

[0034] A bracket, mounted on the side plate via a rotating component on one side, is used to receive and flip the wafer;

[0035] The bracket includes a set of upper limit members and a set of lower limit members. The upper limit members include two blocks symmetrically arranged in the upper part of the bracket to support the wafer when it is flipped to a horizontal state. The lower limit members include two blocks arranged in the lower part of the bracket to prevent the wafer from falling and tilting outward when the bracket receives the wafer, and to support the wafer when it is flipped to a horizontal state.

[0036] The upper part of the bracket is equipped with a rotatable claw, and the inner surface of the claw includes three different angle slopes to accommodate the edges of wafers with different morphologies and / or wafers with different orientations.

[0037] When the wafer is placed on a vertically positioned tray, the claw rotates toward the wafer to prevent it from tipping away from the tray. As the tray and wafer flip from a vertical to a horizontal position, the claw rotates toward the direction away from the wafer to a position below the plane where the wafer is located.

[0038] In one embodiment, the lower limiting member has a guide slope with an inclination angle of 15° to 35° to guide the wafer edge down the guide slope and tilt it toward the bracket side, and to prevent the guide slope from obstructing the wafer from sliding in a horizontal state.

[0039] In one embodiment, the lower limiting member is a wear-resistant and impact-resistant hard material component.

[0040] A third aspect of this application provides a wafer flipping method, including the following steps:

[0041] S1: Control the robotic arm to grasp the wafer and place it on one side of the vertically positioned tray, and position the wafer between the upper limit member and the lower limit member;

[0042] S2: Control the claw drive mechanism to drive the claw to swing vertically to the outside of the top edge of the wafer;

[0043] S3: Control the robotic arm to release the wafer so that the wafer falls onto the lower limit member, and the wafer swings towards the side closer to the bracket until it abuts against the upper limit member or swings away from the bracket until it abuts against the claw.

[0044] S4: Control the flipping drive to flip the bracket from a vertical state to a horizontal state;

[0045] S5: Control the claw drive mechanism to drive the claw to swing vertically and move away from the wafer.

[0046] In one embodiment, the step S1 and step S2 further includes:

[0047] S101: Control the wafer in-situ detection component to identify the wafer's position information and send the position information to the controller;

[0048] S102: The controller sends a control command to the claw drive mechanism to control the claw to perform a swinging motion.

[0049] A fourth aspect of this application provides a wafer processing apparatus, including:

[0050] A wafer flipping device includes a base, a bracket, and a claw, wherein the base has a wafer picking window on its side wall;

[0051] An EFEM robotic arm, located outside the base, is used to pick up a flipped, horizontally positioned wafer from the tray through the wafer picking window.

[0052] The beneficial effects of this application embodiment are as follows: it effectively solves the technical problem that wafers with rough and sharp edges are prone to random tilting and damage during the wafer placement, transport, and flipping processes, while avoiding the problem of wafer slippage due to wear of the lower limit component; this application forms a wafer limiting and supporting mechanism with an all-round, controllable tilting by rotating a bracket on the base, in conjunction with an upper limit component, a hard and wear-resistant lower limit component, and a swingable claw. The claw can swing vertically to the outside of the top edge of the wafer to receive the wafer tilting away from the bracket, thus controlling the top edge of the wafer. The upper limit support suppresses the risk of wafer tipping and falls, solving the problem of existing devices lacking dedicated wafer tipping limits and easily breaking wafers. The lower limit component is made of wear-resistant and impact-resistant hard material, which greatly reduces the damage caused by the impact and sliding friction of the wafer falling with rough edges. It avoids the problem of wafer sliding jamming or failure to be in place due to pits and scratches caused by wear of the lower limit component. On the basis of active and controllable wafer tipping by the claw, it ensures that the wafer is tipped smoothly along the guide slope, while avoiding the problem of wafer tipping aggravation or sliding obstruction caused by unreasonable slope angle, and achieves simultaneous improvement of wafer tipping and sliding. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a schematic diagram of the structure of a normal wafer edge and a guide slope shown in one embodiment of this application;

[0055] Figure 2 This is a schematic diagram of the structure of the wafer with rough, sharp edges and the guide slope shown in this application;

[0056] Figure 3 This is a schematic diagram of the structure of a wafer flipping device and a robotic arm provided in an embodiment of this application;

[0057] Figure 4 This is a schematic diagram of the two wafer flipping directions in the vertical state of the support in this application;

[0058] Figure 5 This is a schematic diagram showing the positional relationship between the wafer and the two lower limit devices in this application;

[0059] Figure 6The images provided are physical photos and structural diagrams of the recess in the lower limit component shown in this application.

[0060] Figure 7 This is a schematic diagram showing the positional relationship between the claw and the wafer in this application;

[0061] Figure 8 For this application Figure 7 A magnified view of a section at point A in the middle;

[0062] Figure 9 This is a schematic diagram illustrating the structural relationship between the wafer flipping trajectory and the gripper and the wafer position in this application;

[0063] Figure 10 This is a schematic diagram illustrating the effect of different inclination slopes of the guide slope on wafer flipping in this application.

[0064] Figure 11 This is a schematic diagram illustrating the effect of different inclination slopes of the guide slope on the wafer slide in this application.

[0065] Figure 12 This is a schematic diagram of the upper limit component in this application;

[0066] Figure 13 This is a schematic diagram of the lower limit component in this application;

[0067] Figure 14 This is a schematic diagram of the wafer slider in the horizontal state of the support in this application;

[0068] Figure 15 This is a schematic diagram of the flexor drive mechanism in this application;

[0069] Figure 16 This is a schematic diagram of the structure of a wafer processing apparatus provided in another embodiment of this application.

[0070] Figure label:

[0071] 100. Wafer; 1. Base; 2. Carrier; 3. Spindle; 4. Upper limit device; 5. Lower limit device; 51. Guide slope; 6. Claw; 61. First slope; 62. Second slope; 63. Third slope; 610. First limit point; 620. Second limit point; 7. Robotic arm; 8. Claw drive mechanism; 81. Telescopic actuator; 82. Transmission block; 83. Swing arm; 9. Wafer in-situ detection assembly; 10. Wafer pick-up window; 11. EFEM robotic arm. Detailed Implementation

[0072] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the specific implementation of this application should fall within the protection scope of the embodiments of this application.

[0073] To keep the drawings concise, each drawing only schematically shows the parts relevant to the disclosure; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."

[0074] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0075] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0076] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0077] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0078] It should be understood that, unless the context clearly states otherwise, the terms "comprising," "including," or "having" as used herein refer to the presence of an element, but do not exclude the presence or addition of one or more other elements. Furthermore, "comprising" and / or "including" as used herein specify the presence of shapes, numbers, steps, operations, members, elements, and / or combinations thereof, and do not exclude the presence or addition of one or more other shapes, numbers, operations, elements, and / or combinations thereof. Some embodiments of this application are described in detail below with reference to the accompanying drawings. Where there is no conflict between the embodiments, the following embodiments and features can be combined with each other. The steps in the following method embodiments are for illustrative purposes only and are not intended to limit this application.

[0079] Embodiments of this application provide a wafer flipping device, which is applied in the field of advanced process wafer 100 processing technology, and is particularly suitable for the transfer and flipping process of wafer 100 in a chemical mechanical polishing (CMP) cleaning unit.

[0080] After wafers are produced from single-crystal silicon ingots through multi-wire dicing, they undergo edge chamfering and grinding according to national standards for semiconductor wafer processing. However, in advanced chip manufacturing processes, the wafer edge morphology is continuously altered during repeated process cycles, eventually forming rough, sharp, and irregularly shaped bevels without smooth transitions. This phenomenon is an inevitable result of the cumulative effect of the process and cannot be completely eliminated through conventional subsequent processes.

[0081] In traditional process nodes, the number of process cycles for thin film deposition, etching, and chemical mechanical polishing is relatively limited, resulting in smaller edge morphology deviations and a process tolerance for the impact on wafer transport and flipping. However, in advanced process nodes, to achieve device miniaturization and multilayer interconnect structure fabrication, the front side of the wafer needs to undergo dozens of chemical mechanical polishing processes and hundreds of etching processes, while simultaneously performing multiple types of thin film deposition processes such as PVD, CVD, and ALD. Under the continuous process effects, the edges undergo significant degradation.

[0082] Especially in the processing of advanced process wafers (7nm and below), advanced process wafers need to undergo dozens of CMP and hundreds of etching processes. Due to the large differences in the properties of multilayer thin film materials and the concentration of edge stress, the superimposed CMP lip protrusions, butterfly depressions and etching micromasks and charge accumulation effects cause the edges to continuously accumulate burrs, grooves, microcracks and other complex three-dimensional morphologies. Moreover, the more processes are performed, the more disordered the morphology becomes, ultimately leading to the failure of the processing solution.

[0083] Specifically, chemical mechanical polishing (CMP) only planarizes the effective area on the front side of the wafer. The polishing pad cannot cover and smooth the edge areas, so once the edge morphology changes, it is difficult to repair. In contrast, deposition processes inevitably form film accumulation and steps in the edge areas, while etching processes cause non-uniform removal of edge material. The repeated superposition of these two processes gradually destroys the standard transition rounded corners, causing the edges to evolve into irregular, sharp bevels without smooth transitions, accompanied by microscopic bumps, chipping, and stress concentration areas. In addition, advanced process wafers are generally developing towards ultra-thin and large-size, significantly increasing the brittleness of the silicon wafer itself. Sharp edge areas are more prone to microcracks and material peeling under mechanical contact and stress, further exacerbating the edge roughness. At the same time, the integration and manufacturing cost of advanced process wafers have increased significantly, with the value of a single wafer reaching dozens of times that of traditional processes. The requirements for controlling fragmentation, particle contamination and edge integrity have increased significantly. Existing flipping devices cannot adapt to wafers with such irregular edge shapes. During the placement, sliding and flipping process, problems such as wafer tipping, jamming, incomplete sliding and even fragmentation are very likely to occur, which has become a key technical problem restricting the yield and equipment stability of advanced processes.

[0084] In the cleaning and drying device of the current CMP cleaning unit, the wafer 100 is spun dry and then picked up by the robot arm 7 and placed vertically on the tray 2. The EFEM robot arm 11 then takes away the horizontally positioned wafer 100.

[0085] like Figure 1 and Figure 2 As shown, it should be noted that the sharp and uneven edges of wafer 100 are an inevitable product of the manufacturing process and cannot be completely eliminated by front-end or back-end processes. Conventional wafer 100 edges have rounded corners to assist in the wafer flipping direction. However, wafer 100 with rough and sharp edges lacks rounded corners and instead has an unrounded bevel. Since the interaction angle of the robotic arm 7 is a vertical 90°, wafer 100 with rough and sharp edges is prone to flipping during placement and flipping, potentially falling from the carrier 2 into the machine and causing fragmentation. Furthermore, if the tilt angle of the bevel is similar to the tilt angle of the guide slope 51 of the lower limit component 5, wafer 100 may get stuck on the guide slope 51, preventing normal wafer flipping and sliding.

[0086] Reference Figure 3As shown in the figure, the specific structure of an existing wafer flipping device is illustrated. The wafer flipping device includes a base 1, a rotating shaft 3 rotatably mounted on the inner side wall of the base 1, and a bracket 2 mounted on the rotating shaft 3. The bracket 2 has an arc-shaped frame structure adapted to the wafer 100. A flipping drive is also mounted on the base 1. The flipping drive is preferably a swing arm structure driven by a servo motor or cylinder. The output end of the flipping drive is connected to the rotating shaft 3 for transmission, and is used to drive the bracket 2 to perform a 0-90° flipping motion around the rotating shaft 3, so that the bracket 2 has a vertical state that vertically supports the wafer 100 and a horizontal state that horizontally supports the wafer 100.

[0087] like Figure 3 , Figure 4 and Figure 5 As shown, furthermore, the bracket 2 is provided with an upper limit member 4 and a lower limit member 5 for supporting the wafer 100. The upper limit member 4 and the lower limit member 5 are located on the upper and lower sides of the rotating shaft 3, respectively. Two upper limit members 4 and two lower limit members 5 are provided. The two upper limit members 4 are symmetrically arranged along the horizontal central axis of the bracket 2, and the two lower limit members 5 are also symmetrically arranged along the horizontal central axis of the bracket 2, forming a four-point support and limiting system for the wafer 100, ensuring the stability of the wafer 100 when placed vertically. Moreover, a guide slope 51 is provided on the side of the lower limit member 5 facing the wafer 100. The guide slope 51 is a smooth inclined surface used to guide the wafer 100 to slide down the slope during the wafer flipping process, and simultaneously guide the wafer 100 to smoothly slide to a horizontal state during the rotation of the bracket 2.

[0088] like Figure 6 As shown, it should be noted that the existing lower limit component 5 has good self-lubrication but poor wear resistance. This lower limit component 5 allows the wafer 100 placed on it to slide downwards along the guide slope 51 of the lower limit component 5 under gravity. However, when the robot arm 7 places the wafer 100 onto the carrier 2, the actual placement position is approximately 12mm above the guide slope 51 of the lower limit component 5, allowing the wafer 100 to fall freely. This is to prevent the wafer 100 from coming into complete contact with the lower limit component 5, causing damage due to hard contact. However, the impact contact between the rough-edged wafer 100 and the lower limit component 5 during free fall, as well as long-term sliding friction, will damage the surface of the lower limit component 5, forming pits, grooves, and scratches. This makes it difficult for the wafer 100 to fall and flatten properly when flipped to a horizontal position, resulting in misalignment and ultimately preventing the EFEM robot arm 11 from picking up the wafer. It also affects the wafer 100 in a vertical position, after which the bottom edge of the wafer 100 guides the slope 51 to slide down and flip.

[0089] Therefore, to avoid the aforementioned issues with the lower limit component 5 during prolonged use, the lower limit component 5 is made of a wear-resistant and impact-resistant hard material, and a block with a large guide slope 51 area is selected to increase the force-bearing area between the wafer 100 and the lower limit component 5. The material of the lower limit component is PEEK (polyetheretherketone) or alumina ceramic. PEEK is preferred because it has high hardness, high wear resistance, and good impact resistance. It does not easily generate dust and will not damage the wafer 100. It effectively prevents the rough and sharp edges of the wafer 100 from rubbing against the lower limit component 5 during the slippage and flipping process, thus avoiding the formation of pits, grooves, and scratches, and solving the problem of slippage jamming.

[0090] Furthermore, since traditional wafer flipping devices lack a dedicated limiting structure, the contact friction distance between wafer 100 and lower limit component 5 is large, which not only easily causes damage to lower limit component 5, but also easily generates particulate contamination. This cannot meet the requirements of advanced processes for the cleanliness and edge nanometer-level integrity of wafer 100, and is especially unsuitable for advanced packaging ultra-thin wafers 100 with a thickness of 20μm~50μm and large-size 12-inch high-brittle wafers 100.

[0091] like Figure 3 and Figure 7 As shown in the figure, the claw limiting assembly of the wafer flipping device is located on the top of the bracket 2 and between the two upper limit members 4. The claw limiting assembly includes a claw 6 and a claw drive mechanism 8 for driving the claw 6 to swing vertically. The claw 6 is hinged to the top of the bracket 2, one end of the claw 6 extends to the back of the bracket 2 for hinged to the output end of the claw drive mechanism 8, and the other end extends towards the front of the bracket 2. The claw 6 can swing vertically. When the robot arm 7 moves the wafer 100 to the bearing surface of the bracket 2, the wafer in-place detection component 9 on the bracket 2 detects that the wafer 100 is in place. At this time, the controller then controls the claw drive mechanism 8 to start. Under its drive, the claw 6 swings vertically to the outside of the top edge of the wafer 100, so that the claw 6 is in a limiting support state. Then, after the robotic arm 7 releases the clamped wafer 100, under normal operating conditions, the wafer 100 will be close to the side of the upper limit member 4, and the wafer 100 will not be in contact with the claw 6. However, when the wafer 100 is flipped, that is, when the wafer 100 is tilted away from the upper limit member 4, because of the presence of the claw 6, the wafer 100 will abut against the inner side of the claw 6, effectively suppressing the risk of the wafer 100 flipping and preventing the wafer 100 from falling off the carrier 2.

[0092] like Figure 8As shown, it should be noted that since the robotic arm 7 grasps the already cleaned wafer 100, a large contact area between the wafer 100 and the claw 6 could cause contamination of the wafer 100. Therefore, the inner surface of the claw 6 facing the wafer 100 has a gradually sloping structure, consisting of a first slope 61 and a second slope 62. The transition between the first slope 61 and the second slope 62 is smooth, without sharp edges, to avoid chipping or breaking of the wafer 100 edges when in contact with it. The first slope 61 is located close to the bracket 2, and the second slope 62 is located on the side of the first slope 61 away from the bracket 2. The angle between the first slope 61 and the second slope 62 is an obtuse angle, preferably 120°-150°. The junction of the two forms a first limiting point 610, which is a limiting point for the wafer 100 during small-scale wafer flipping.

[0093] like Figure 9 As shown, due to the influence of the wafer placement station of the robotic arm 7, the position of the wafer 100 placed on the lower limit member 5 may deviate. To prevent the scaffold 6 from failing to cover the wafer 100 when it is tilted in the lower middle section of the guide slope 51 of the lower limit member 5, a third slope 63 is provided on the side of the second slope 62 of the scaffold 6 away from the first slope 61. It is understandable that if the coverage area of ​​the scaffold 6 is too long, it is easy to interfere with the robotic arm for vertical wafer placement and horizontal wafer picking. Therefore, the minimum height of the third slope 63 of the scaffold 6 is determined so that the scaffold 6 can limit and cover the wafer 100 when it is tilted at the bottom of the lower limit member 5. The angle between the third slope 63 and the second slope 62 is also an obtuse angle, preferably 100°-120°. The junction of the two forms a second limiting point 620, which is a rounded transition. This second limiting point 620 is the limiting point for wafer 100 during large-scale wafer flipping and sliding outward and downward along the guide slope 51. The first limiting point 610 and the second limiting point 620 can minimize the contact area with the wafer 100 while achieving wafer flipping limiting, thus avoiding the introduction of dirt into the cleaned and dried wafer 100.

[0094] like Figure 9As shown, more importantly, when the bracket 2 is in a vertical position and the claw 6 is in a limiting support position, the highest point of the inner side of the claw 6 is higher than the highest point of the wafer 100 when it is placed in the middle position of the guide slope 51. It should be noted that the middle position is the highest point on the guide slope 51 where the wafer 100 can be placed during normal wafer flipping, and the height difference between the two is h1. The highest point of the inner side of the claw 6 is higher than the highest point of the wafer 100 to avoid collision between the claw 6 and the top of the wafer 100 when the claw 6 swings inward. The height difference between the middle position and the highest position of the guide slope 51 in the tilt direction is h2, where the difference between h1 and h2 ranges from 3mm to 5mm, and the height of h1 is greater than the height of h2 to avoid interference or hard contact between the wafer 100 and the claw 6, and to avoid wafer 100 fragmentation. In this embodiment, for a 12-inch wafer 100, h2=8~10mm and h1=13~15mm are preferred, satisfying the requirement that h1>h2+3~5mm.

[0095] like Figure 10 and Figure 11 As shown, further, in the prior art, the problem of wafer flipping and sliding misalignment is often improved by using the guide slope 51 on the lower limit member 5 of the wafer 100 interaction. This method can meet the requirements of tilting guidance and sliding of conventional wafers 100, but it is difficult to apply to wafers 100 with rough and sharp edges. Because when the lower limit member 5 flips to the horizontal with the carrier 2, the closer the guide slope 51 is to the vertical, the more obvious the gravity effect on the wafer 100 is, and the smoother the sliding is. However, in order to ensure that the wafer does not flip, the lower limit member 5 usually needs to be set with a large slope guide slope 51. However, a large slope guide slope 51 is not conducive to the sliding of wafers 100 with sharp edges. Reducing the slope can improve the sliding effect but will increase the frequency of wafer flipping. It is difficult to balance the angles required for both wafer flipping and sliding. In this application, the active controllability of wafer flipping is achieved by setting the claw 6. The slope of the guide slope 51 can be set to a small slope (when the lower limit member 5 is in a horizontal state, the guide slope 51 is close to vertical), preferably 80°-85°, which can ensure the gravity sliding effect when the wafer 100 is flipped, and avoid the risk of wafer flipping being aggravated by a large slope.

[0096] like Figure 12 , Figure 13 and 14As shown, it should be further explained that when the bracket 2 is flipped from a vertical state to a horizontal state under the drive of the flipping drive, the wafer 100, guided by gravity and the guide slope 51, smoothly slides along the lower limit member 5 to the horizontal support position. At this time, the upper limit member 4 and the lower limit member 5 jointly support the wafer 100 horizontally. Furthermore, the first limit point 610 and the second limit point 620 need to control the tilt angle of the wafer 100 after flipping within a β angle, which is 2~3°. If the tilt angle is less than 2°, when the wafer 100 is flipped towards the claw 6, its surface is likely to come into contact with the claw 6, thus causing contamination of the wafer 100. If the angle is greater than 3°, the limiting of the claw 6 is too loose and cannot effectively suppress the wafer from flipping outward. Furthermore, because the limiting segment of the upper limit member 4 is extremely short, there is a risk that the wafer 100 may fall beyond the upper limit member 4 during the flipping process, causing it to fail to slide into place and potentially damaging the wafer 100 due to impact with the edge of the upper limit member 4. Therefore, a tilt angle of 2-3° can reduce the impact force between the wafer 100 and the upper limit member 4 when the wafer 100 is flipped to a horizontal state, and also prevent the wafer 100 from falling out of the limiting range of the upper limit member 4.

[0097] like Figure 14 As shown, in one embodiment of this application, the grappling drive mechanism 8 includes a telescopic driver 81, a transmission block 82, and a rocker arm 83. The telescopic driver 81 is preferably a thin cylinder or an electric push rod, fixedly installed on the back of the bracket 2 (without affecting the placement of the wafer 100), and its telescopic direction is set along the radial direction of the bracket 2; the transmission block 82 is slidably connected to the slide rail on the back of the bracket 2 and fixedly connected to the output end of the telescopic driver 81, and can slide linearly along the radial direction of the bracket 2 under the drive of the telescopic driver 81; the rocker arm 83 is a rigid connecting rod, one end of which is hinged to the transmission block 82 through a hinge shaft, and the other end is hinged to the back of the grappling 6 through another hinge shaft, forming a crank rocker arm 83 mechanism.

[0098] Specifically, when the piston rod of the telescopic actuator 81 extends, it drives the transmission block 82 to slide outward along the radial direction of the bracket 2. The swing arm 83 swings clockwise under the drive of the transmission block 82, thereby pushing the claw 6 to swing vertically towards the side of the wafer 100 until the claw 6 is in a limited support state. When the piston rod of the telescopic actuator 81 retracts, it drives the transmission block 82 to slide inward along the radial direction of the bracket 2. The swing arm 83 then pulls the claw 6 to swing vertically away from the side of the wafer 100 until the claw 6 is in an avoidance state.

[0099] In one embodiment of this application, a controller is also provided on the base 1. The wafer in-situ detection component 9 is electrically connected to the controller, preferably a PLC controller. The controller is also electrically connected to the telescopic driver 81 and the flipping driver of the claw drive mechanism 8. The wafer in-situ detection component 9 collects the position information of the wafer 100 in real time, including whether it is in place and its precise position, and converts the position information into an electrical signal and sends it to the controller. The controller has a built-in preset program that can analyze and process the position information, generate corresponding control commands, and send them to the telescopic driver 81 and the flipping driver to realize the automated control of the claw 6 swinging and the bracket 2 flipping without manual intervention, which can improve the efficiency and stability of wafer 100 processing.

[0100] Furthermore, the controller is used to control the tray 2 to achieve wafer flipping, and the controller is specifically used to perform the following steps:

[0101] When the flipping angle is less than the first angle, control the bracket 2 to flip at a uniform acceleration;

[0102] When the flipping angle is not less than the first angle and less than the second angle, control the bracket 2 to flip at a constant speed;

[0103] When the flipping angle is greater than the second angle, control the bracket 2 to flip with uniform deceleration;

[0104] Preferably, the first angle is 20° and the second angle is 60°. When the flip angle is less than 20°, the wafer 100 is still resting on the upper limit member 4 or the claw 6. At this time, the carrier 2 flips at a uniform acceleration to reduce the initial flipping time. However, when the flip angle of the carrier 2 exceeds 20° but does not exceed 60°, the wafer 100 may detach from the claw 6 at any time under the action of gravity. In order to prevent the wafer 100 from failing to fall into the bearing and limiting area of ​​the upper limit member 4 after flipping, it is necessary to control the carrier 2 to flip at a uniform speed to prevent the wafer 100 from being thrown out of the bearing and limiting area of ​​the upper limit member 4 during the flipping process. When the bracket exceeds 60°, the wafer 100 is already in contact with the upper limit member 4, but the wafer 100 is not yet in a horizontal state. At this time, the bracket 2 is controlled to decelerate and rotate slowly to avoid damage to the wafer 100 caused by sudden stopping after the bracket 2 rotates to the position. The edge of the wafer 100 that is in contact with the lower limit member 5 slides down the guide slope 51 to ensure that the wafer 100 is smoothly slid to a horizontal state.

[0105] During the flipping process, the maximum safe angular acceleration is negatively correlated with the guide slope angle. This is because the steeper the slope (the larger θ becomes), the greater the component of gravity pulling down the slope, making it easier for the wafer to slip. The gentler the slope (the smaller θ becomes), the less likely it is to slip, so a larger angular acceleration can be used, resulting in higher slipping efficiency.

[0106] In the above scheme, the flipping angle refers to the angle at which the bracket has completed flipping when it flips from a vertical state to a horizontal state;

[0107] The formula for calculating the maximum safe angular acceleration is as follows:

[0108]

[0109] Meaning of each symbol:

[0110] : Maximum permissible angular acceleration (rad / s²);

[0111] Gravitational acceleration;

[0112] The static friction coefficient between the wafer and the guide slope;

[0113] :Guide slope angle;

[0114] Wafer radius;

[0115] As shown in the formula above, the wafer's acceleration is related to the tilt angle of the guide slope. During wafer flipping, the angular acceleration during the start-stop phase is limited. ≤ cause inertial force The sum of the force and the component of gravity still does not exceed the maximum static friction force. ( (To ensure the quality of the wafer), avoid slippage caused by sudden impact.

[0116] The wafer in-situ detection component 9 preferably uses a laser rangefinder or a photoelectric sensor, which is fixedly installed in the central area of ​​the bracket 2 to detect in real time whether the wafer 100 is in the predetermined support position; the claw drive mechanism 8 is installed on the back of the bracket 2 and is connected to the claw 6 for transmission, and is used to drive the claw 6 to swing vertically.

[0117] Another embodiment of this application discloses a wafer flipping device, including an L-shaped base 1. The base 1 includes a horizontal bottom plate and a vertical side plate. Both the bottom plate and the side plate can prevent wafer 100 debris and contaminants from splashing and contaminating surrounding precision components. A bracket 2, which is annular in shape, is used to support the wafer. One end of the bracket 2 is connected to a rotating component, which is a rotating shaft 3 or a rotatable mounting bracket. The bracket 2 is connected to the side plate through the rotating component. The bracket can rotate about the rotating component as an axis so that the wafer 100 located on the bracket 2 can be flipped along with the bracket 2.

[0118] The bracket 2 includes a set of upper limit members 4 and a set of lower limit members 5. The upper limit members 4 include two blocks symmetrically arranged in the upper part of the bracket 2 to support the wafer 100 when it is flipped to a horizontal state. The lower limit members 5 include two blocks arranged in the lower part of the bracket 2 to prevent the wafer 100 from falling or tilting outward when the bracket 2 receives the wafer 100. It should be noted that tilting outward means that the wafer 100 tilts away from the upper limit members 4. Moreover, the upper limit members 4 can also support the wafer 100 when it is flipped to a horizontal state.

[0119] The bracket 2 is equipped with a rotatable claw 6 on its upper part. Specifically, the claw 6 is located between two blocks of the upper limit member 4. The inner surface of the claw 6 includes three different angle slopes to accommodate the edges of wafers 100 with different morphologies and / or wafers 100 with different orientations.

[0120] When the wafer 100 is placed on the vertically positioned bracket 2, the claw 6 rotates toward the direction closer to the wafer 100 to prevent the wafer 100 from tilting away from the bracket 2. Furthermore, as the bracket 2 and the wafer 100 flip from a vertical to a horizontal position, the claw 6 rotates away from the wafer 100 to a position below the plane where the wafer 100 is located, so that the wafer 100 can be picked up by the EFEM robot 11.

[0121] Furthermore, the stop block of the lower limit member 5 has a guide slope 51 with an inclination angle of 15° to 35° to guide the edge of the wafer 100 to slide down along the guide slope 51 and tilt toward the side of the bracket 2, and to prevent the guide slope 51 from blocking the wafer 100 from sliding in a horizontal state.

[0122] In one embodiment, the lower limit member 5 is a wear-resistant and impact-resistant hard material component.

[0123] One embodiment of this application discloses a wafer flipping method. This wafer flipping method is based on the aforementioned wafer flipping device and is applicable to wafer 100 flipping operations after CMP cleaning and drying processes. Each step is automatically controlled by a controller, requiring no manual intervention. The specific workflow is as follows:

[0124] First, prepare the wafer 100 for loading. Control the flipping drive to keep the tray 2 in a vertical state. At the same time, control the robot arm 7 to grab the cleaned and dried wafer 100 and transfer it to the bearing surface of the tray 2, and place the wafer 100 in the predetermined bearing area between the two upper limit members 4 and the two lower limit members 5.

[0125] Then, the wafer in-situ detection component 9 performs wafer in-situ detection, identifying and collecting the position information of wafer 100. If wafer 100 is detected to be in the predetermined support area, the in-situ signal is converted into an electrical signal and sent to the controller. After receiving the in-situ signal from the wafer in-situ detection component 9, the controller immediately sends a claw 6 extension command to the telescopic driver 81 of the claw drive mechanism 8. After receiving the command, the piston rod of the telescopic driver 81 extends outward, driving the transmission block 82 to slide radially outward along the bracket 2. The swing arm 83 swings under the drive of the transmission block 82, thereby pushing the claw 6 to swing vertically to the outside of the top edge of wafer 100. The claw 6 is in a limited support state, completing the preparation for the wafer flipping limit.

[0126] Then, the control robot 7 releases its clamping on the wafer 100, allowing the wafer 100 to fall onto the guide slope 51 of the lower limit member 5 under the action of gravity. After the wafer 100 is in place, if it is tilted towards the side closer to the bracket 2, the inner side of its top edge abuts against the upper limit member 4, and is limited by the upper limit member 4. If it is tilted away from the bracket 2, the outer side of its top edge abuts against the first limit point 610 or the second limit point 620 of the claw 6, and the claw 6 controls its tilt angle within 2~3°, thereby achieving the tilting limit.

[0127] After confirming that the wafer 100 is in place and has completed the limit, the controller sends a flip command to the flip drive to control the drive shaft 3 to rotate, thereby causing the bracket 2 to rotate 90° counterclockwise around the shaft 3, gradually switching from a vertical state to a horizontal state. During the flip process, the wafer 100 slides smoothly along the guide slope 51 of the lower limit member 5 under the guidance of gravity and the guide slope 51, and is finally horizontally supported on the bracket 2 by the upper limit member 4 and the lower limit member 5.

[0128] After the controller detects that the bracket 2 has completed its flip and is in a horizontal state, it sends a claw retraction command to the telescopic driver 81 of the claw drive mechanism 8. The piston rod of the telescopic driver 81 retracts inward, driving the transmission block 82 to slide radially inward along the bracket 2. The swing arm 83 pulls the claw 6 to swing vertically and away from the wafer 100, so that the claw 6 is in an avoidance state, leaving operating space for the EFEM robot 11 to pick up the wafer.

[0129] After completing the above steps, wafer 100 remains horizontally supported on tray 2, awaiting EFEM robot 11 to pick it up. Once the wafer is picked up, the controller controls the flipping drive to flip tray 2 from the horizontal position back to the vertical position, entering the next wafer 100 flipping operation cycle.

[0130] like Figure 16As shown, another embodiment of this application provides a wafer processing device, which includes a wafer flipping device and an EFEM robot 11. A wafer picking window 10 is provided on the side wall of the base 1 of the wafer flipping device. The size of the wafer picking window 10 is adapted to the size of the gripper of the EFEM robot 11, and its position corresponds to the wafer 100 support position when the tray 2 is in a horizontal state, so as to ensure that the EFEM robot 11 can accurately grasp the wafer 100.

[0131] It should be noted that the EFEM robot 11 is located outside the base 1 and is a standard front-end wafer pick-up robot for semiconductor equipment. Its grippers can extend into the inside of the base 1 through the pick-up window 10 to pick up the wafer 100 from the horizontal tray 2 and transfer it to the subsequent wafer transfer box, realizing dry-in and dry-out transfer of the wafer 100.

[0132] The overall workflow of the wafer processing equipment is as follows: After the wafer 100 is processed by the CMP cleaning and drying unit, it is transferred by the robot arm 7 to the tray 2 of the wafer flipping device. After being flipped to a horizontal state by the above-mentioned wafer 100 flipping method, the EFEM robot arm 11 grabs the horizontal wafer 100 through the wafer picking window 10, completing the wafer 100 flipping and picking operation. The whole process is highly automated and there are no problems such as wafer 100 flipping, fragmentation, slippage and jamming. It is suitable for the processing needs of wafers 100 with rough and sharp edges.

[0133] It should be further noted that the technical solution of this embodiment is applicable to the 100-fold wafer flipping operation after the semiconductor chemical mechanical polishing (CMP) cleaning and drying process, and is particularly optimized for the problem of improper wafer flipping and sliding of 12-inch semiconductor wafers with rough and sharp edges; those skilled in the art can make adaptive adjustments to the relevant parameters according to the actual wafer specifications and equipment conditions, and such adjustments are all within the protection scope of this application.

[0134] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A wafer flipping device, characterized in that, include: Base; A bracket, rotatably mounted on the base, is used to rotate the wafer to a horizontal position. The bracket is provided with an upper limit member and a lower limit member. The lower limit member is a wear-resistant and impact-resistant hard material component. The lower limit member has a guide slope with an inclination angle of 15° to 35°. The swivel claw is mounted on the upper part of the bracket; When the bracket is in a vertical position, the claw is configured to swing vertically to the outside of the top edge of the wafer to receive the wafer and provide limiting support for the top edge of the wafer.

2. The wafer flipping device according to claim 1, characterized in that, The lower limit component is made of PEEK or alumina ceramic.

3. The wafer flipping device according to claim 1, characterized in that, The inner side of the claw has a first slope and a second slope located on the side of the first slope away from the bracket. The angle between the first slope and the second slope is an obtuse angle, and the junction of the first slope and the second slope forms a first limiting point. When the bracket is in a vertical position, the first limiting position is used to abut against the outer side of the top edge of the wafer.

4. The wafer flipping device according to claim 3, characterized in that, The claw also has a third slope that is in contact with the second slope. The third slope is located on the side of the second slope away from the first slope and the angle between the third slope and the second slope is an obtuse angle. The junction of the second slope and the third slope forms a second limiting point. When the carrier is in a vertical position and the wafer slides outward and downward along the guide slope during the wafer flipping process away from the carrier, the second limiting point is used to abut against the outer edge of the top edge of the wafer.

5. The wafer flipping device according to claim 4, characterized in that, The first and second limiting points are configured to control the tilt angle of the wafer after flipping within an angle β, where the angle β is 2° to 3°, so as to reduce the impact force between the wafer and the upper limiting member when the wafer is flipped to a horizontal state and to prevent the wafer from detaching from the upper limiting member.

6. The wafer flipping device according to claim 1, characterized in that, There are two upper limit positioners and two lower limit positioners, which are arranged horizontally and symmetrically. The claw is located between the two upper limit positioners.

7. The wafer flipping device according to claim 3, characterized in that, When the bracket is in a vertical position and the claw is in a limiting support position, the highest point of the inner side of the claw is higher than the highest point of the wafer, and the height difference between the two is h1. The height difference between the middle position of the guide slope in the direction of inclination and the highest position of the guide slope is h2; The difference between h1 and h2 is between 3mm and 5mm, which is used to avoid collision between the claw and the top of the wafer when the claw swings inward.

8. The wafer flipping device according to claim 1, characterized in that, The bracket is also equipped with a wafer in-situ detection component for detecting the wafer's in-situ status and a claw drive mechanism for driving the claw to swing. The wafer in-situ detection component is electrically connected to a controller, which is electrically connected to the claw drive mechanism. The wafer in-situ detection component is used to identify the wafer's position information and send the position information to the controller. The controller is used to generate control commands and send them to the claw drive mechanism to control the claw's movement.

9. The wafer flipping device according to claim 8, characterized in that, The claw drive mechanism includes: A telescopic actuator is mounted on the bracket; A transmission block is disposed at the output end of the telescopic actuator and is used to slide radially along the bracket under the drive of the telescopic actuator; The swing arm is hinged at one end to the transmission block and at the other end to the flexure. The telescopic actuator is configured to drive the transmission block to slide radially, thereby causing the pawl to swing via the rocker arm.

10. The wafer flipping apparatus according to claim 8, characterized in that, The controller is used to control the carrier to achieve wafer flipping, and the controller is specifically used to perform the following steps: When the flipping angle is less than the first angle, the bracket is controlled to flip at a uniform acceleration. When the flipping angle is not less than the first angle and less than the second angle, the bracket is controlled to flip at a constant speed. When the flipping angle is greater than the second angle, the bracket is controlled to flip with uniform deceleration; During the overturning process, the maximum safe angular acceleration of the overturning is negatively correlated with the inclination angle of the guide slope.

11. A wafer flipping device, characterized in that, include: The base, shaped like an L, includes a horizontal base plate and vertical side plates to prevent wafer debris contaminants from splashing. A bracket, mounted on the side plate via a rotating component on one side, is used to receive and flip the wafer; The bracket includes a set of upper limit members and a set of lower limit members. The upper limit members include two blocks symmetrically arranged in the upper part of the bracket to support the wafer when it is flipped to a horizontal state. The lower limit members include two blocks arranged in the lower part of the bracket to prevent the wafer from falling and tilting outward when the bracket receives the wafer, and to support the wafer when it is flipped to a horizontal state. The upper part of the bracket is equipped with a rotatable claw, and the inner surface of the claw includes three different angle slopes to accommodate the edges of wafers with different morphologies and / or wafers with different orientations. When the wafer is placed on a vertically positioned tray, the claw rotates toward the wafer to prevent it from tipping away from the tray. As the tray and wafer flip from a vertical to a horizontal position, the claw rotates toward the direction away from the wafer to a position below the plane where the wafer is located.

12. The wafer flipping apparatus according to claim 11, characterized in that, The lower limit member has a guide slope with an inclination angle of 15° to 35° to guide the wafer edge to slide down the guide slope and tilt toward the bracket side, and to prevent the guide slope from obstructing the wafer from sliding in a horizontal state.

13. The wafer flipping apparatus according to claim 11, characterized in that, The lower limit component is a wear-resistant and impact-resistant hard material component.

14. A wafer flipping method, characterized in that, Using the wafer flipping apparatus according to any one of claims 1-10 and 11-13 includes the following steps: S1: Control the robotic arm to grasp the wafer and place it on one side of the vertically positioned tray, and position the wafer between the upper limit member and the lower limit member; S2: Control the claw drive mechanism to drive the claw to swing vertically to the outside of the top edge of the wafer; S3: Control the robotic arm to release the wafer so that the wafer falls onto the lower limit member, and the wafer swings towards the side closer to the bracket until it abuts against the upper limit member or swings away from the bracket until it abuts against the claw. S4: Control the flipping drive to flip the bracket from a vertical state to a horizontal state; S5: Control the claw drive mechanism to drive the claw to swing vertically and move away from the wafer.

15. The wafer flipping method according to claim 14, characterized in that, The steps between S1 and S2 also include: S101: Control the wafer in-situ detection component to identify the wafer's position information and send the position information to the controller; S102: The controller sends a control command to the claw drive mechanism to control the claw to perform a swinging motion.

16. A wafer processing equipment, characterized in that, include: The wafer flipping device according to any one of claims 1-10 and 11-13, the wafer flipping device includes a base, a bracket and a claw, and the side wall of the base is provided with a wafer picking window; An EFEM robotic arm, located outside the base, is used to pick up a flipped, horizontally positioned wafer from the tray through the wafer picking window.

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