Wafer inspection device
By using a single reflective sensor and a linear module in the wafer inspection device, the structure is simplified and the inspection accuracy is improved. This solves the problems of device complexity and space occupation in the prior art, and achieves efficient and accurate wafer slide-out inspection.
Patent Information
- Application Number
- CN202521796301.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-22
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-08-22
AI Technical Summary
Existing wafer inspection devices are complex in structure, require high installation accuracy, occupy a large space, and have poor adaptability, making it difficult to efficiently detect wafer slip-out within the wafer cassette.
A single reflective sensor emits a detection signal in the vertical direction. The wafer status is determined by whether the detection signal is blocked by the wafer. Combined with a linear module and guide rail, accurate detection of wafers in the wafer box is achieved, which simplifies the structure and reduces the installation complexity.
It achieves simple installation, reduces the number of structural components and space occupation, improves detection accuracy and adaptability, avoids the risk of sensor loosening and collision, and enhances the accuracy of wafer position detection.
Smart Images
Figure CN224684670U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of semiconductor wafer processing technology, and in particular to a wafer inspection device. Background Technology
[0002] In semiconductor wafer fabrication, wafers must be stored in wafer cassettes to ensure their cleanliness and safety. If a wafer slips out or bulges out, it may not only break itself, but also collide with equipment during handling or processing, damaging equipment components and even affecting the accuracy and stability of subsequent processes. Therefore, detecting whether a wafer has slipped out of the wafer cassette is crucial.
[0003] Existing detection devices mostly employ through-beam optical fibers or reflective sensors with reflectors. Through-beam optical fibers consist of a transmitter and a receiver located above and below the wafer cassette opening, respectively, forming a detection beam that passes vertically through the opening. Reflective sensors with reflectors integrate the transmitter and receiver on one side of the opening, with a reflector positioned correspondingly on the other side. The beam is emitted from the transmitter, reflected by the reflector, and returns to the receiver. If a wafer slides out of the wafer cassette opening, it blocks the beam transmission, allowing the detection device to determine that a wafer has slipped out of the cassette.
[0004] However, using through-beam optical fibers requires strict concentricity of the fibers; otherwise, the beam may easily deviate, leading to detection failure. Using reflective sensors, on the other hand, requires the reflector surface to be clean and perpendicular to the beam path. Both methods involve numerous structural components, occupying significant installation space, and suffer from high installation accuracy requirements, structural complexity, and poor spatial adaptability.
[0005] Therefore, there is an urgent need to develop a wafer inspection device to solve the above-mentioned technical problems. Utility Model Content
[0006] The purpose of this invention is to provide a wafer inspection device that reduces the number of structural components, significantly reduces the space occupied, and simplifies the installation process, achieving the effect of easy installation.
[0007] To achieve this objective, the present invention adopts the following technical solution:
[0008] This utility model provides a wafer inspection device for detecting whether a wafer inside a wafer cassette protrudes from the opening of the wafer cassette; the wafer inspection device includes:
[0009] A wafer cassette stage, wherein the wafer cassette is connected to the top of the wafer cassette stage, and the wafer cassette contains a plurality of wafers stacked vertically inside;
[0010] A mounting base is disposed on the top of the wafer cassette stage, and the mounting base is disposed adjacent to the opening of the wafer cassette along a first direction;
[0011] A first detection sensor is fixed to the mounting base. The first detection sensor is configured to emit a detection signal upward in the vertical direction and determine the state of the wafer by whether the detection signal is blocked by the wafer.
[0012] In some embodiments, the mounting base is movably connected to the top of the wafer cassette stage, and the mounting base is capable of approaching or moving away from the opening of the wafer cassette along the first direction.
[0013] In some embodiments, the wafer cassette includes a bottom wall fixedly connected to the top of the wafer cassette stage, the bottom wall having a notch, and the mounting base being movable into the notch.
[0014] In some embodiments, the first detection sensor is configured as a reflective sensor, and the detection signal is an optical signal.
[0015] In some embodiments, the wafer inspection apparatus further includes a second detection sensor and a linear module. The second detection sensor is disposed facing the opening of the wafer cassette. The wafer cassette stage is connected to the linear module, and the linear module is capable of driving the wafer cassette stage to move in a vertical direction. The second detection sensor cooperates with the linear module to detect the state of each wafer in the wafer cassette.
[0016] In some embodiments, the wafer inspection apparatus further includes a mounting bracket, on which the second inspection sensor is disposed.
[0017] In some embodiments, two second detection sensors are provided, and the two second detection sensors are spaced apart on the mounting bracket along a second direction, which is the width direction of the wafer cassette and perpendicular to the first direction.
[0018] In some embodiments, the linear module includes a drive motor and a ball screw. The ball screw is connected to the output end of the drive motor, and the wafer cassette stage is connected to the ball screw. The drive motor can drive the ball screw to rotate, thereby causing the wafer cassette stage to move in the vertical direction.
[0019] In some embodiments, the linear module further includes a guide rail extending in a vertical direction, and the wafer cassette stage is connected to the guide rail.
[0020] In some embodiments, two guide rails are provided, which are disposed on opposite sides of the ball screw, and the wafer cassette stage is connected to both guide rails.
[0021] The beneficial effects of this utility model are:
[0022] The wafer inspection device provided by this utility model has a first detection sensor positioned on the adjacent side of the wafer cassette opening, emitting a detection signal vertically upwards. When the wafer is not sliding out, the detection signal is unobstructed; when the wafer slides out, the portion of the wafer protruding from the wafer cassette opening blocks the detection signal. The first detection sensor can determine the wafer's state by identifying whether the signal is blocked. Thus, wafer sliding out detection can be achieved using only one sensor, eliminating the need for paired transmitters and receivers required by through-beam optical fibers, and also eliminating the need for reflective plates required by reflective sensors. This reduces the number of structural components, significantly reducing the space occupied, and simplifies the installation process, achieving a simple installation effect. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.
[0024] Figure 1 This is a three-dimensional structural schematic diagram of the wafer inspection device provided in this embodiment of the utility model.
[0025] In the picture:
[0026] 1. Wafer box; 11. Bottom wall; 111. Notch;
[0027] 2. Wafer;
[0028] 3. Wafer cell stage;
[0029] 4. Mounting bracket;
[0030] 5. First detection sensor;
[0031] 6. Second detection sensor;
[0032] 7. Linear module; 71. Drive motor; 72. Ball screw; 73. Guide rail;
[0033] 8. Install the bracket. Detailed Implementation
[0034] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0036] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0037] In the description of this utility model, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are used only for the convenience of describing this utility model and for simplifying the description, and do not 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 utility model. Furthermore, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0038] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0039] In this invention, unless otherwise explicitly 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.
[0040] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.
[0041] like Figure 1 As shown, this embodiment provides a wafer inspection device for detecting whether a wafer 2 inside a wafer cassette 1 protrudes from the opening of the wafer cassette 1, that is, detecting whether a wafer 2 slides out from the opening of the wafer cassette 1.
[0042] The wafer inspection device includes a wafer carrier stage 3, a mounting base 4, and a first inspection sensor 5.
[0043] A wafer cassette 1 is connected to the top of a wafer cassette stage 3, and multiple wafers 2 are stacked vertically inside the wafer cassette 1. A mounting base 4 is disposed on the top of the wafer cassette stage 3, and is adjacent to the opening of the wafer cassette 1 along a first direction. A first detection sensor 5 is fixed to the mounting base 4, and is configured to emit a detection signal upward in a vertical direction, and determine the state of the wafer 2 by whether the detection signal is blocked by the wafer 2. The first direction is the sliding direction of the wafer 2 when it slides out of the wafer cassette 1.
[0044] In specific implementation, when no wafer 2 slides out of the opening of the wafer box 1, the detection signal emitted vertically upward by the first detection sensor 5 is unobstructed. Based on this signal state, it can be determined that all wafers 2 in the wafer box 1 are in normal positions. When a wafer 2 protrudes from the opening of the wafer box 1, that is, one or more wafers 2 slide out of the opening of the wafer box 1 along the first direction, the detection signal emitted vertically upward by the first detection sensor 5 will be blocked by the slid-out wafer 2. By recognizing this signal blocking state, the first detection sensor 5 can determine that there is an abnormal situation where a wafer 2 has slid out.
[0045] The wafer inspection device provided in this embodiment has a first detection sensor 5 positioned on the adjacent side of the opening of the wafer housing 1 and emitting a detection signal vertically upwards. When the wafer 2 is not slid out, the detection signal is unobstructed; when the wafer 2 slides out, the portion of the wafer 2 protruding from the opening of the wafer housing 1 blocks the detection signal. The first detection sensor 5 can determine the state of the wafer 2 by identifying whether the signal is blocked. In this way, the detection of the wafer 2 sliding out can be achieved using only one sensor, eliminating the need for paired transmitters and receivers required by through-beam optical fibers, and also eliminating the need for reflective plates required by reflective sensors. This reduces the number of structural components, significantly reduces the space occupied, and simplifies the installation process, achieving the effect of easy installation.
[0046] In some embodiments, the first detection sensor 5 is configured as a reflective sensor, and the detection signal is an optical signal. This configuration achieves slip-out detection by reflecting the optical signal from the wafer 2 itself. Specifically, when no wafer 2 has slid out, the optical signal emitted by the first detection sensor 5 is unobstructed and cannot be reflected back to the first detection sensor 5; when wafer 2 has slid out, the slid-out wafer 2 will reflect the optical signal, and the first detection sensor 5 can determine the anomaly by receiving the reflected signal. Compared to reflective sensors with reflectors, this method eliminates the need for additional reflectors, reduces structural components, avoids detection errors caused by reflector contamination or misalignment, and lowers installation accuracy requirements and maintenance costs.
[0047] It should be noted that when only one wafer 2 slides out, the first detection sensor 5 will detect that wafer 2; when multiple wafers 2 slide out at the same time, the first detection sensor 5 will detect the wafer 2 closest to itself.
[0048] like Figure 1 As shown, in some embodiments, the mounting base 4 is movably connected to the top of the wafer cassette stage 3, and the mounting base 4 can move closer to or further away from the opening of the wafer cassette 1 along a first direction.
[0049] With this configuration, the mounting base 4 can move together with the first detection sensor 5, allowing the distance between the first detection sensor 5 and the opening of the wafer cassette 1 to be flexibly adjusted. When the first detection sensor 5 is closer to the opening, the wafer 2 only needs to slide out a small amount to block the detection signal, achieving sensitive detection of minute slippage; when the first detection sensor 5 is slightly away from the opening, it can be adapted to the maximum allowable slippage of the wafer 2 that the machine can accept, avoiding misjudgment of minute displacements within the normal range.
[0050] like Figure 1 As shown, in some embodiments, the wafer cassette 1 includes a bottom wall 11, which is fixedly connected to the top of the wafer cassette stage 3. The bottom wall 11 has a notch 111, and the mounting base 4 can move into the notch 111.
[0051] With this setup, when the first detection sensor 5 needs to detect a smaller amount of slippage, the mounting base 4 can be as close as possible to the opening of the wafer cassette 1 through the notch 111, avoiding the inability to get close to the opening of the wafer cassette 1 due to the obstruction of the bottom wall 11, thereby further optimizing the position adjustment range of the first detection sensor 5.
[0052] In actual production processes, wafer mapping is typically required for multiple wafers 2 within a wafer cassette 1. This involves using sensors or lasers to detect the state of each layer of wafers 2 within the wafer cassette 1, generating mapping data reflecting the position and arrangement of the wafers 2. This data guides operations such as precise handling of the wafers 2. However, conventional wafer mapping methods involve fixing sensors to moving parts, which then drive the sensors to extend into the wafer cassette 1 to scan the wafers. This can easily cause the sensors to loosen, and when the moving parts overlap with other structures, there is a risk of collision if a malfunction occurs.
[0053] Therefore, such as Figure 1 As shown, the wafer inspection device in this embodiment also includes a second detection sensor 6 and a linear module 7. The second detection sensor 6 is arranged facing the opening of the wafer cassette 1. The wafer cassette stage 3 is connected to the linear module 7. The linear module 7 can drive the wafer cassette stage 3 to move in the vertical direction. The second detection sensor 6 cooperates with the linear module 7 to detect the state of each wafer 2 in the wafer cassette 1.
[0054] With this setup, when the wafer carrier stage 3 moves vertically, the wafer cassette 1 moves synchronously, so that the second detection sensor 6 does not need to extend into the wafer cassette 1. It can cooperate with the vertical movement of the wafer cassette 1 to complete the state detection of each layer of wafer 2, realize the wafer mapping function, and thus avoid the possible sensor loosening problem and structural collision risk in the prior art.
[0055] like Figure 1 As shown, in some embodiments, the wafer inspection apparatus further includes a mounting bracket 8, on which the second inspection sensor 6 is disposed. The mounting bracket 8 provides a stable and reliable mounting base for the second inspection sensor 6.
[0056] like Figure 1 As shown, in some embodiments, two second detection sensors 6 are provided, and the two second detection sensors 6 are spaced apart on the mounting bracket 8 along a second direction, which is the width direction of the wafer cassette 1 and perpendicular to the first direction.
[0057] With this setup, the two second detection sensors 6 can detect two different positions (such as the two sides of the edge of the wafer 2) along the second direction on the same layer. When the wafer 2 is in a normal horizontal state without tilt, the two second detection sensors 6 will detect the wafer 2 at the same vertical height. If the wafer 2 is tilted, the height positions on both sides along the second direction will be different, and the two second detection sensors 6 will detect the wafer 2 at different vertical heights. By comparing the detection signals of the two sensors, it is possible to accurately determine whether the wafer 2 is tilted, which helps to improve the accuracy of detecting the position and arrangement of the wafer 2.
[0058] like Figure 1 As shown, in some embodiments, the linear module 7 includes a drive motor 71 and a ball screw 72. The ball screw 72 is connected to the output end of the drive motor 71, and the wafer cassette stage 3 is connected to the ball screw 72. The drive motor 71 can drive the ball screw 72 to rotate, thereby driving the wafer cassette stage 3 to move in the vertical direction.
[0059] By employing a linear module 7 that combines a drive motor 71 and a ball screw 72, high-precision driving and positioning can be provided for the vertical movement of the wafer cassette stage 3. The drive motor 71 can achieve stable power output, while the ball screw 72, with its helical transmission structure and rolling friction characteristics, has the characteristics of high transmission efficiency and smooth operation. It can accurately convert the rotational motion of the drive motor 71 into the linear motion of the wafer cassette stage 3, ensuring the positional accuracy and motion stability of the wafer cassette stage 3 when moving in the vertical direction.
[0060] like Figure 1 As shown, in some embodiments, the linear module 7 further includes a guide rail 73 extending vertically, to which the wafer cassette stage 3 is connected. This configuration provides precise guiding constraints for the movement of the wafer cassette stage 3, ensuring smooth vertical movement and preventing wobbling or displacement of the wafer cassette stage 3.
[0061] Furthermore, in some embodiments, two guide rails 73 are provided, which are located on opposite sides of the ball screw 72, and the wafer cassette stage 3 is connected to both guide rails 73. The two guide rails 73 can provide more balanced support and guidance for the wafer cassette stage 3, avoiding tilting or offset of the wafer cassette stage 3 due to unilateral force, thus achieving force balance.
[0062] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A wafer inspection device, characterized in that, Used to detect whether the wafer (2) inside the wafer box (1) protrudes from the opening of the wafer box (1); The wafer inspection device includes: A wafer cassette stage (3) is provided, wherein a wafer cassette (1) is connected to the top of the wafer cassette stage (3), and a plurality of wafers (2) are stacked in a vertical direction inside the wafer cassette (1); Mounting base (4) is disposed on the top of the wafer cassette stage (3), and the mounting base (4) is disposed adjacent to the opening of the wafer cassette (1) along the first direction; A first detection sensor (5) is fixed to the mounting base (4). The first detection sensor (5) is configured to emit a detection signal upward in the vertical direction and determine the state of the wafer (2) by whether the detection signal is blocked by the wafer (2).
2. The wafer inspection apparatus according to claim 1, characterized in that, The mounting base (4) is movably connected to the top of the wafer cassette stage (3), and the mounting base (4) can move closer to or further away from the opening of the wafer cassette (1) along the first direction.
3. The wafer inspection apparatus according to claim 2, characterized in that, The wafer cassette (1) includes a bottom wall (11), which is fixedly connected to the top of the wafer cassette stage (3). The bottom wall (11) has a notch (111), and the mounting base (4) can move into the notch (111).
4. The wafer inspection apparatus according to claim 1, characterized in that, The first detection sensor (5) is configured as a reflective sensor, and the detection signal is a light signal.
5. The wafer inspection apparatus according to any one of claims 1 to 4, characterized in that, The wafer inspection device further includes a second inspection sensor (6) and a linear module (7). The second inspection sensor (6) is disposed facing the opening of the wafer cassette (1). The wafer cassette stage (3) is connected to the linear module (7). The linear module (7) can drive the wafer cassette stage (3) to move in the vertical direction. The second inspection sensor (6) cooperates with the linear module (7) to detect the state of each wafer (2) in the wafer cassette (1).
6. The wafer inspection apparatus according to claim 5, characterized in that, The wafer inspection device also includes a mounting bracket (8), on which the second inspection sensor (6) is mounted.
7. The wafer inspection apparatus according to claim 6, characterized in that, Two second detection sensors (6) are provided, and the two second detection sensors (6) are spaced apart on the mounting bracket (8) along a second direction, which is the width direction of the wafer box (1) and perpendicular to the first direction.
8. The wafer inspection apparatus according to claim 5, characterized in that, The linear module (7) includes a drive motor (71) and a ball screw (72). The ball screw (72) is connected to the output end of the drive motor (71). The wafer cassette stage (3) is connected to the ball screw (72). The drive motor (71) can drive the ball screw (72) to rotate, thereby driving the wafer cassette stage (3) to move in the vertical direction.
9. The wafer inspection apparatus according to claim 8, characterized in that, The linear module (7) also includes a guide rail (73) that extends vertically, and the wafer cassette stage (3) is connected to the guide rail (73).
10. The wafer inspection apparatus according to claim 9, characterized in that, There are two guide rails (73), which are located on opposite sides of the ball screw (72). The wafer cassette stage (3) is connected to both guide rails (73).