Cavity wafer position detection device and detection method

Abstract

This application relates to the field of wafer manufacturing technology and discloses an in-cavity wafer position detection device and method. The in-cavity wafer position detection device is disposed within a reaction cavity, which contains a wafer-bearing stage. The detection device includes an optical detection device, a lifting mechanism, and a controller. The optical detection device is disposed at a preset plane spaced apart from the bearing surface of the stage. The optical detection device includes a first detection device, a second detection device, and a third detection device that detect the wafer edge position along a preset optical path on the preset plane. The preset optical paths of the first, second, and third detection devices are located in different tangential directions of the same circle. The lifting mechanism is vertically and flexibly disposed within the reaction cavity. The in-cavity wafer position detection device and method provided in this application can detect whether the wafer within the cavity is within a predetermined position.

Description

Technical Field

[0001] This application relates to the field of wafer manufacturing technology, and in particular to an in-cavity wafer position detection device and detection method. Background Technology

[0002] With the continuous development of semiconductor technology, the application of semiconductor integrated circuits is becoming increasingly widespread, and the integration density on wafers is also increasing. Wafers integrate various circuit element structures on silicon wafers to achieve specific electrical functions. Wafers are also the carriers for producing chips, and as the importance of chips grows daily, the development of wafer manufacturing technology becomes increasingly crucial for economic and social development.

[0003] During the manufacturing process, wafers move between different chambers, requiring constant monitoring of their position. If a wafer is not positioned correctly, subsequent processing steps can be affected, potentially leading to wafer fragmentation or loss. Therefore, accurately detecting the wafer's position within the chamber is a crucial issue. Summary of the Invention

[0004] The purpose of this application is to provide an intracavity wafer position detection device and detection method, which can detect whether the wafer in the cavity is within a predetermined position.

[0005] To address the aforementioned technical problems, embodiments of this application provide an in-cavity wafer position detection device. The detection device is disposed within a reaction cavity, and a wafer-bearing stage is provided within the reaction cavity. The detection device includes an optical detection device, a lifting mechanism, and a controller. The optical detection device is disposed at a preset plane spaced apart from the bearing surface of the bearing stage. The optical detection device includes a first detection device, a second detection device, and a third detection device that detect the wafer edge position on a preset optical path on the preset plane. The preset optical paths of the first detection device, the second detection device, and the third detection device are located in different tangential directions of the same circle. The lifting mechanism is vertically and vertically disposed within the reaction cavity and is used to lift the wafer located on the bearing surface of the bearing stage to the preset plane. The controller is used to determine whether the wafer position on the bearing surface of the bearing stage has shifted based on the detection signal from the optical detection device. If at least one of the first, second, and third detection devices fails to detect the wafer position, the controller determines that the wafer is not within a predetermined position on the bearing surface of the bearing stage.

[0006] This application also provides an in-cavity wafer in-situ inspection method, wherein after the wafer is placed on the support surface of the support stage, the inspection method includes:

[0007] The wafers on the support surface of the support platform are lifted to the preset position by the lifting mechanism;

[0008] The controller determines whether the wafer is within a predetermined position on the bearing surface of the carrier stage based on the detection results of the first detection device, the second detection device, and the third detection device. If all three devices detect the wafer position, the controller determines that the wafer is within the predetermined position on the bearing surface of the carrier stage. If at least one of the three devices fails to detect the wafer position, the controller determines that the wafer is not within the predetermined position on the bearing surface of the carrier stage.

[0009] The cavity wafer position detection device and method provided in this application detect different positions at the wafer edge by constructing different optical paths around a predetermined position where the wafer is located. By combining detection information from multiple different positions, it determines whether the wafer is in the predetermined position. This achieves the detection of whether the wafer within the cavity is within the predetermined position.

[0010] In some implementations, the controller obtains the wafer thickness information according to the following expression: T = V * t; where T is the wafer thickness, V is the moving speed of the lifting mechanism, and t is the time required for the wafer to move from one side surface into the preset plane to the other side surface leaving the preset plane.

[0011] In some embodiments, the first detection device, the second detection device, and the third detection device each include a light source and a light signal detector. The light sources of the first detection device, the second detection device, and the third detection device emit light rays that propagate along their respective preset light paths. The light signal detectors of the first detection device, the second detection device, and the third detection device are located on their respective preset light paths and are used to detect the light rays emitted by their respective light sources.

[0012] In some implementations, the controller determines that the wafer portion is located on a preset optical path when the intensity of the optical signal received by the optical signal detector is lower than a preset value.

[0013] In some implementations, the light source and the light signal detector are located outside the reaction cavity, and the reaction cavity is provided with a sapphire window through which light passes in a preset optical path.

[0014] In some embodiments, the point on the bearing surface of the support stage where the circle tangent to each preset optical path is projected is located within 1 to 3 millimeters of a predetermined position.

[0015] In some implementations, if the first detection device, the second detection device, and the third detection device all fail to detect the wafer position, the controller determines that there is no wafer or the wafer is broken.

[0016] In some embodiments, the lifting mechanism is provided with multiple support points, which are arranged around the center of a predetermined position.

[0017] In some implementations, multiple support points are located on the same plane, and this plane is parallel to the bearing surface. Attached Figure Description

[0018] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0019] Figure 1 This is a schematic diagram of the structure of the intracavity wafer position detection device provided in some embodiments of this application when it is applied;

[0020] Figure 2 This is a schematic diagram of the structure of the in-cavity wafer position detection device provided in some embodiments of this application during detection;

[0021] Figure 3 This is a schematic diagram of the detection structure of each detection device in the cavity wafer position detection device provided in some embodiments of this application;

[0022] Figure 4 This is a schematic diagram of the optical path structure of the intracavity wafer position detection device provided in some embodiments of this application when the wafer is offset;

[0023] Figure 5 This is a schematic diagram of another optical path structure of the intracavity wafer position detection device provided in some embodiments of this application when the wafer is offset;

[0024] Figure 6 This is a flowchart of an intracavity wafer position detection method provided in some embodiments of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in this application can be implemented. The division of the various embodiments below is for the convenience of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0027] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0028] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0029] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0030] To detect the position of wafers, the industry typically uses optical or vacuum sensors on robotic arms to indirectly detect wafers in place during wafer transport. The drawback of this detection method is that it cannot predict the wafer's position within the cavity, and problems such as wafer breakage or slippage cannot be anticipated. By the time the robotic arm is inserted or the wafer is removed, a collision has already occurred.

[0031] In the first scenario, the vacuum robot uses vacuum adsorption to determine if the wafer is in place, but it cannot make a precise judgment on the wafer's position. This method requires a check-load approach when picking up and placing wafers; the robot first tentatively reaches out before using vacuum or optical signals to determine if the wafer has been successfully picked up.

[0032] In the second scenario, the AWC (Advanced Wafer Carrier) sensor determines and corrects the wafer's position and location by monitoring the process module (PM) / transport module (TM) gates as the wafer passes through them. This method requires not only tentatively reaching out during wafer retrieval but also retracting the arm before assessing the wafer's status.

[0033] In other words, both of the above detection methods have drawbacks when detecting wafer position. Furthermore, they cannot detect whether the wafer is in the intended position during the detection process. This means that information about whether the wafer is correctly positioned cannot be obtained during processing, easily affecting the processing flow due to the wafer not being in the correct location. It may also lead to wafer fragmentation or loss.

[0034] To determine whether a wafer within a cavity is in a predetermined position, some embodiments of this application provide an in-cavity wafer position detection device. By constructing different optical paths around the predetermined position of the wafer, different positions at the wafer edge are detected. By combining detection information from multiple different positions, it is determined whether the wafer is in the predetermined position. This achieves the detection of whether the wafer within the cavity is in a predetermined position.

[0035] The following is combined with Figures 1 to 6 This application describes an intracavity wafer position detection device and method provided in some embodiments. The detection device is disposed within a reaction chamber 100, and a support stage 200 for supporting a wafer 300 is disposed within the reaction chamber 100.

[0036] like Figures 1 to 3As shown, some embodiments of this application provide an in-cavity wafer position detection device including an optical detection device, a lifting mechanism 21, and a controller. An optical inspection device is disposed at a preset plane spaced apart from the bearing surface 210 of the support stage 200. The optical inspection device includes a first inspection device 11, a second inspection device 12, and a third inspection device 13 that detect the edge position of the wafer 300 on a preset optical path on the preset plane. The preset optical paths of the first inspection device 11, the second inspection device 12, and the third inspection device 13 are located in different tangential directions of the same circle. A lifting mechanism 21 is movably disposed in the reaction chamber 100. The lifting mechanism 21 is used to lift the wafer 300 located on the bearing surface 210 of the support stage 200 to the preset plane. A controller is used to determine whether the position of the wafer 300 on the bearing surface 210 of the support stage 200 has shifted according to the detection signal of the optical inspection device. If at least one of the first inspection device 11, the second inspection device 12, and the third inspection device 13 fails to detect the position of the wafer 300, the controller determines that the wafer 300 is not within the predetermined position on the bearing surface 210 of the support stage 200.

[0037] Optical inspection devices detect the position of the object under test using light signals, avoiding interference with the processing environment within the chamber. Each detection device in the optical inspection device performs detection along different preset optical paths, based on a circle defined by three points. These preset optical paths are designed along different tangential directions on the same circle. In other words, the detection results from three devices can be combined to determine whether the wafer 300 is within its predetermined position after placement. If the wafer 300's position shifts, some detection devices will fail to detect its location. The number of detection devices can also exceed three, for example, four, five, or six.

[0038] The lifting mechanism 21 can lift and lower the wafer 300 on the support stage 200, moving it to a preset plane where the optical inspection device is located for inspection. The preset plane can be a position above the support stage 200 that does not affect the wafer 300's processing technology. This allows the wafer 300 to enter the position of the preset optical path, facilitating the inspection of the wafer 300's position without the influence of other factors.

[0039] The controller is responsible for acquiring the detection results and communicates with different detection devices. It can synthesize the detection results from different devices to analyze whether wafer 300 is within the predetermined position. When all three detection devices detect the position of wafer 300, it can be determined that wafer 300 is within the predetermined position. Figures 4 to 6As shown, if the wafer 300 position is not detected on the preset optical path of some of the detection devices, it is determined that the wafer 300 is not in the predetermined position and the wafer 300 has shifted position. If all detection devices fail to detect the wafer 300 position, it is determined that the wafer 300 is fragmented or there is no wafer 300.

[0040] The intracavity wafer position detection device provided in some embodiments of this application constructs different optical paths at the edge of a predetermined location where the wafer 300 is located, and detects different positions at the edge of the wafer 300. By combining the detection information from multiple different positions, it determines whether the wafer 300 is at the predetermined position. This achieves the detection of whether the wafer 300 within the cavity is within the predetermined position.

[0041] In addition, some embodiments of this application provide an in-situ non-destructive testing method for the in-cavity wafer position detection device, which does not require vacuum adsorption and will not cause unnecessary damage to the wafer 30020 and the process cavity.

[0042] In some embodiments, the thickness parameters of wafer 300 can also be detected using an optical inspection device. The controller can determine the thickness information of wafer 300 based on the following expression:

[0043] T = V * t;

[0044] Where T is the thickness of wafer 300, V is the moving speed of lifting mechanism 21, and t is the time required for wafer 300 to move from one side surface into the preset plane to the other side surface leaving the preset plane.

[0045] In other words, the thickness of wafer 300 can be detected by controlling its movement. After the lifting mechanism 21 moves one side of wafer 300 into the preset plane, the detection device detects the position of wafer 300, and the controller records this time point. The lifting mechanism 21 continues to move until the other side of wafer 300 leaves the preset plane, at which point the detection device returns to a state of not detecting an object, and the controller records this time point again. Thus, the time required for the lifting mechanism 21 to move wafer 300 into and out of the preset optical path of the detection device can be determined.

[0046] like Figure 3 As shown, the first detection device 11, the second detection device 12, and the third detection device 13 each include a light source 101 and a light signal detector 102. The light source 101 of the first detection device 11, the second detection device 12, and the third detection device 13 emits light rays that propagate along their respective preset light paths. The light signal detectors 102 of the first detection device 11, the second detection device 12, and the third detection device 13 are located on their respective preset light paths and are used to detect the light rays emitted by their respective light sources.

[0047] like Figure 1 and Figure 2 As shown, the optical signal detector 102 can be located on the direct optical path of the detection light. When the intensity of the optical signal received by the optical signal detector 102 is lower than a preset value, the controller determines that the wafer 300 is in place.

[0048] The optical path is designed as a through-beam type, with the optical path positioned above the support stage 200. When the lifting mechanism 21 is not raising the wafer 300, the optical path containing the detection light is unobstructed by the wafer 300. When the lifting mechanism 21 raises the wafer 300 to a preset plane within the cavity, the optical path containing the detection light is blocked by the wafer 300. The presence or absence of the wafer 300 causes a change in the light intensity signal, which determines whether the wafer 300 is in place.

[0049] The light source 101 can emit detection light rays to a specific location, and the intensity of these light rays can be detected by the optical signal detector 102. When there is no wafer 300 under test blocking the preset optical path, the detection light rays emitted by the light source 101 can be received by the optical signal detector 102 without obstruction. At this time, the optical signal detector 102 detects a relatively high intensity of light. However, when the wafer 300 under test blocks the preset optical path, the detection light rays emitted by the light source 101 cannot reach the optical signal detector 102. At this time, the optical signal detector 102 detects a relatively low intensity of light.

[0050] In other words, when the intensity of the light signal detected by the optical signal detector 102 decreases below a preset value, the controller can determine that a portion of the wafer 300 exists in the preset optical path based on the detection result. If the intensity of the light signal detected by the optical signal detector 102 is higher than the preset value, the controller can determine that there is no portion of the wafer 300 in the preset optical path based on the detection result. Thus, the controller can combine the detection results of each detection device to determine whether the wafer 300 is covered at different positions, and further determine whether the wafer 300 is within the predetermined position.

[0051] Additionally, the detection device may include a filter for filtering the signal. It may also include an amplifier for amplifying the signal. The preset optical paths of each detection device can be evenly arranged to form a triangle connected end-to-end, or they can be arranged separately. The number of detection devices can also be increased to enable the detection of more wafer 300 locations.

[0052] In some embodiments, the light source 101 and the light signal detector 102 may be located outside the reaction cavity 100, and the reaction cavity 100 is provided with a sapphire window for light to pass through in a preset light path.

[0053] By placing the detection device outside the reaction chamber 100, the internal environment of the reaction chamber 100 can be avoided, enabling the detection of the wafer 300 position without affecting the processing technology. Furthermore, the sapphire window allows the detection light emitted from the light source to pass through easily.

[0054] In practice, two light-transmitting holes can be opened opposite each other on the reaction chamber 100, and the sapphire window can be installed at the two light-transmitting holes. The detection light emitted by the light source 101 is focused at one of the light-transmitting holes by the incident optical fiber. After passing through the chamber, the light converges at the detection optical fiber port at the other light-transmitting hole and is received by the light detector 102.

[0055] In some embodiments, the point on the bearing surface 210 of the bearing stage 200 where the circle tangent to each preset optical path is projected is located within 1 mm to 3 mm of a predetermined position.

[0056] In other words, when the wafer 300 is within the predetermined position, the preset optical path of the detection light passes through the edge of the wafer 300, thus successfully detecting part of the position of the wafer 300.

[0057] Furthermore, the 1 to 3 millimeters within the predetermined position ensures that the wafer 300 has a certain offset during placement, facilitating rapid placement of the wafer 300.

[0058] In some embodiments, the lifting mechanism 21 may be provided with multiple support points, which are arranged around the center of a predetermined position.

[0059] In this way, multiple support points can support the wafer 300 along the circumference, which can make the lifting and moving of the wafer 300 more stable during the lifting process.

[0060] In addition, multiple support points can be located on the same plane, and this plane is parallel to the bearing surface 210.

[0061] In other words, during the lifting mechanism 21's lifting of the wafer 300, the surface of the wafer 300 can rest horizontally on multiple support points. Each support point can provide good support for the surface of the wafer 300, preventing the wafer 300 from easily tilting or moving during the lifting process.

[0062] Some embodiments of this application also provide a detection method for in-situ detection of wafer 300 using the above-described in-cavity wafer position detection device. The detection method includes the following steps after the wafer 300 is placed on the support surface 210 of the support stage 200:

[0063] The lifting mechanism 21 lifts the wafer 300 located on the bearing surface 210 of the bearing platform 200 to the preset plane.

[0064] The controller determines that the wafer 300 is within a predetermined position on the bearing surface 210 of the carrier stage 200 based on the detection results of the first detection device 11, the second detection device 12, and the third detection device 13. If all three devices detect the position of the wafer 300, the controller determines that the wafer 300 is within the predetermined position on the bearing surface 210 of the carrier stage 200. If at least one of the three devices fails to detect the position of the wafer 300, the controller determines that the wafer 300 is not within the predetermined position on the bearing surface 210 of the carrier stage 200.

[0065] After the wafer position detection is completed, the wafer 300 can be placed back from the preset plane to the bearing surface 210 of the bearing platform 200 by the lifting mechanism 21.

[0066] By employing a specific optical path design, the position status of wafer 300 can be detected during wafer inspection, avoiding unnecessary dangerous actions, minimizing production risks, and saving significant costs associated with post-inspection issues.

[0067] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes can be made in form and detail without departing from the spirit and scope of this application.

Claims

1. A cavity wafer position detection device, disposed within a reaction cavity, wherein a wafer-carrying stage is provided within the reaction cavity, characterized in that, include: An optical inspection device is disposed at a preset plane that is spaced apart from the bearing surface of the support stage. The optical inspection device includes a first inspection device, a second inspection device, and a third inspection device that detect the edge position of the wafer on a preset optical path on the preset plane. The preset optical paths of the first inspection device, the second inspection device, and the third inspection device are located in different tangential directions of the same circle. A lifting mechanism is provided in the reaction chamber and is used to lift the wafer located on the support surface of the support platform to the preset plane. The controller is used to determine whether the position of the wafer on the bearing surface of the carrier stage has shifted based on the detection signal of the optical detection device. If the first detection device, the second detection device, and the third detection device all detect the wafer position, the controller determines that the wafer is within a predetermined position on the bearing surface of the carrier stage; if at least one of the first detection device, the second detection device, and the third detection device fails to detect the wafer position, the controller determines that the wafer is not within the predetermined position on the bearing surface of the carrier stage; if none of the first detection device, the second detection device, and the third detection device detect the wafer position, the controller determines that the wafer is fragmented or there is no wafer. The point on the bearing surface of the support platform where the circle tangent to each of the preset optical paths is projected is located within 1 to 3 millimeters of the predetermined position.

2. The intracavity wafer position detection device according to claim 1, characterized in that, The controller obtains the wafer thickness information based on the following expression: T = V * t; Wherein, T is the thickness of the wafer, V is the moving speed of the lifting mechanism, and t is the time required for the wafer to move from one side of the surface into the preset plane to the other side of the surface leaving the preset plane.

3. The intracavity wafer position detection device according to claim 1 or 2, characterized in that, The first detection device, the second detection device, and the third detection device each include a light source and a light signal detector. The light sources of the first detection device, the second detection device, and the third detection device emit light rays that propagate along their respective preset light paths. The light signal detectors of the first detection device, the second detection device, and the third detection device are located on their respective preset light paths and are used to detect the light rays emitted by their respective light sources.

4. The intracavity wafer position detection device according to claim 3, characterized in that, When the intensity of the optical signal received by the optical signal detector is lower than a preset value, the controller determines that the wafer portion is located on the preset optical path.

5. The intracavity wafer position detection device according to claim 1, characterized in that, The lifting mechanism is provided with multiple support points, which are arranged around the center of the predetermined position.

6. The intracavity wafer position detection device according to claim 5, characterized in that, The multiple support points are located on the same plane, and the plane is parallel to the bearing surface.

7. A detection method for in-situ wafer detection using the intracavity wafer position detection device according to any one of claims 1 to 6, characterized in that, After the wafer is placed on the support surface of the stage, the process includes: The wafer located on the support surface of the support platform is lifted to the preset plane by the lifting mechanism; The controller determines whether the wafer is within a predetermined position on the bearing surface of the carrier stage based on the detection results of the first, second, and third detection devices. If all three devices detect the wafer position, the controller determines that the wafer is within the predetermined position on the bearing surface of the carrier stage. If at least one of the three devices fails to detect the wafer position, the controller determines that the wafer is not within the predetermined position on the bearing surface of the carrier stage. If none of the three devices detect the wafer position, the controller determines that the wafer is fragmented or there is no wafer.

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