Wafer detector structure and wafer detection device
By introducing a dual detection arm structure into the wafer detection device, using laser signals to detect the wafer position, the problem of wafer detection sensor breaking false chips is solved, and safe and reliable wafer position detection is achieved to avoid equipment damage and product quality influence.
Patent Information
- Application Number
- CN202422212850.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-10
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-09-10
AI Technical Summary
In the prior art, wafer detection sensors are prone to smash protruding fake films during the scanning process, affecting the process and product film quality.
A wafer detector structure is designed, including a first detection arm and a second detection arm fixed relative to each other, for detecting wafers at predetermined positions and non-predictable positions, and precise position determination is achieved through laser emission and reception components, and scanning is stopped in time when a protruding wafer is detected.
Avoid fake films breaking, ensure equipment safety, protect product film quality, and improve process stability and reliability.
Smart Images
Figure CN223123248U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor manufacturing technology, and particularly to a wafer detector structure and a wafer detection device. Background Art
[0002] In the process of wafer manufacturing, a boat is an essential device, which is a storage box or storage rack for wafers, used to store, transport, and process wafers. Since wafers are very thin and fragile, the boat can protect the wafers from being damaged during transportation, transfer, and processing. Generally, a boat contains multiple wafer placement slots (Slots), and each placement slot can hold one wafer.
[0003] The temperature and airflow control models of batch processing equipment such as furnaces in the wafer production process usually need to be carried out under the full-boat state. Therefore, if the number of product wafers is insufficient before the process starts, dummy wafers need to be used for filling. Or, according to the process requirements, side dummy wafers are placed at both ends of the boat.
[0004] Dummy wafers are usually reused multiple times or downgraded from product wafers of other machines, so there is a risk of warping of the dummy wafers after multiple uses. The space of the boat is very precious, and as many placement slots as possible will be set in a unit space. Correspondingly, the gap between the slots is very compact, and only a robot can be used to charge or discharge wafers, with high precision requirements. Therefore, when the dummy wafer warps, it is very easy for the robot to drag the warped dummy wafer away from the predetermined position when it exits after placing the warped dummy wafer into the placement slot.
[0005] In the prior art, after the wafers are placed in the boat, it is necessary to confirm again whether there are wafers on each placement slot of the boat. A mapping sensor is used to scan each placement slot of the boat to confirm whether there is a wafer on the placement slot. Once the dummy wafer deviates from the predetermined position, even if the deviation is very small, it is very easy to collide during the process of the detection sensor scanning the wafers along the boat, and the protruding dummy wafer will be broken. If not discovered in time, it will affect the entire process, damage the equipment, or affect the quality of the product wafers.
[0006] Therefore, a new wafer detector structure and a wafer detection device are needed to avoid the above-mentioned collision problems. Summary of the Utility Model
[0007] In view of the above-mentioned disadvantages of the prior art, the purpose of the present application is to provide a wafer detector structure and a wafer detection device, which are used to solve the problem of breaking the protruding dummy wafers during the process of the detection sensor scanning the wafer along the boat.
[0008] On the one hand, an embodiment of the present application provides a wafer detector structure for wafer position detection, including a first detection arm and a second detection arm with relatively fixed positions. A first detection unit is arranged at the end of the first detection arm, and a second detection unit is arranged at the end of the second detection arm; in the direction perpendicular to the wafer surface, the first detection unit and the second detection unit are separated by a first distance; in the direction parallel to the wafer surface, the first detection unit and the second detection unit are separated by a second distance, and the distance from the first detection unit to the wafer is less than the distance from the second detection unit to the wafer.
[0009] In some embodiments, the first detection unit is configured to at least detect whether there is a wafer at a predetermined position, and the second detection unit is configured to at least detect whether there is a wafer outside the predetermined position.
[0010] In some embodiments, the end of the first detection arm includes a first fork, and the first detection unit is arranged at the end of the first fork; the end of the second detection arm includes a second fork, and the second detection unit is arranged at the end of the second fork.
[0011] In some embodiments, the first detection unit and the second detection unit respectively include a signal transmitting end and a signal receiving end, and the signal transmitting end and the signal receiving end are respectively oppositely arranged at the tops of two branches of the first fork and the second fork.
[0012] In some embodiments, the signal transmitting end is a laser emitting component, and the signal receiving end is a laser receiving component.
[0013] In some embodiments, the first distance is greater than 5 cm.
[0014] In some embodiments, the second distance = D1 + D2, where D1 is the depth of the first detection unit extending into the vertical projection plane of the wafer located at the predetermined position, and D2 is the maximum distance that the wafer protrudes from the predetermined position but does not intersect the moving trajectory of the first detection arm.
[0015] On the other hand, the present application also provides a wafer detection device, which includes a controller, a moving device, and the wafer detector structure described in the above embodiments. The wafer detector structure is fixedly arranged on the moving device, and the controller is electrically connected to the moving device and the wafer detector structure respectively, and is used to control the moving device to drive the wafer detector structure to scan the storage position of the wafer to determine whether the wafer exists at the storage position.
[0016] In some embodiments, the scanning movement trajectory of the wafer detection device is perpendicular to the wafer plane; in the initial scanning movement direction, the second detection unit of the wafer detector structure is in the front, and the first detection unit of the wafer detector structure is in the back.
[0017] In some embodiments, it includes a warning unit. When the second detection unit detects the wafer, the controller stops the moving device and issues an abnormal alarm through the warning unit.
[0018] As described above, a wafer detector structure and a wafer detection device of the present application have the following beneficial effects: Once there is a protruding dummy wafer in the susceptor, it is possible to timely detect the collision risk and stop the scanning process of the wafer detection device before the wafer detection device collides with the protruding dummy wafer, which can avoid problems such as damaging the equipment and affecting the quality of product wafers caused by breaking the dummy wafer. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The following drawings detail the exemplary embodiments disclosed in the present application. Wherein the same reference numerals represent similar structures in several views of the drawings. Those of ordinary skill in the art will understand that these embodiments are non-limiting, exemplary embodiments, and the drawings are only for the purpose of illustration and description, and are not intended to limit the scope of the present application. Embodiments in other ways may also achieve the inventive concept in the present application. It should be understood that the drawings are not drawn to scale.
[0020] Wherein:
[0021] Figure 1 is a top view of the relative position relationship between the wafer and the detection sensor shown in some embodiments;
[0022] Figure 2 is a top view of the relative position relationship between the protruding dummy wafer and the detection sensor shown in some embodiments;
[0023] Figure 3 is a top view of the wafer detector structure shown in some embodiments of the present application;
[0024] Figure 4 is a side view of the wafer detector structure shown in some embodiments of the present application;
[0025] Figure 5 It is a schematic structural diagram of a wafer detection device shown according to some embodiments of the present application. Detailed implementation manners
[0026] The following description provides specific application scenarios and requirements of the present application, aiming to enable those skilled in the art to manufacture and use the content in the present application. For those skilled in the art, various local modifications to the disclosed embodiments are obvious, and the general principles defined here can be applied to other embodiments and applications without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the disclosed embodiments, but has the broadest scope consistent with the claims.
[0027] During the process, if there are insufficient product wafers, unstable temperature fields and airflow fields will be generated, resulting in poor control performance and poor process effects. Therefore, before the process starts, if the number of product wafers is insufficient, dummy wafers can be used for filling to make up for the vacancy of product wafers, aiming to ensure that the process is carried out in a full-boat state, and effects such as high-precision temperature control and stable gas flow model can be achieved. Or, since the temperature and airflow uniformity at both ends of the susceptor are the worst during the process, the process effects generated are the worst compared to the wafers at other positions. Therefore, edge dummy wafers are usually placed at both ends of the susceptor to avoid wasting product wafers.
[0028] Reference Figure 1 Shown is a top view of the relative position relationship between the wafer and the detection sensor. Due to space limitations, process equipment is designed very compactly, so the gap set between the detection sensor and the wafer is limited. The position of the wafer 2 in the susceptor (reference Figures 3 to 5 ) is determined, hereinafter referred to as the predetermined position; the relative position between the detection sensor 1 and the wafer 2 is also preset in advance. A signal unit 13 is provided at the end of the bracket of the detection sensor 1. Under normal circumstances, the set relative position between the detection sensor 1 and the wafer 2 can ensure that when the detection sensor 1 moves and scans past the wafer 2, the detection signal 14 of the signal unit 13 can intersect with the wafer 2, thereby determining the presence of the wafer 2.
[0029] Reference Figure 2 Shown, when the wafer 2' (usually a dummy wafer) deviates from the predetermined position, the protruding wafer 2' will overlap with the moving path of the detection sensor 1, causing motion interference and collision. As Figure 2 Shown, the wafer 2' collides with the end 12 of the bracket 11 of the detection sensor 1. Since the shape of the bracket 11 is different in different embodiments, it may also collide with other parts of the bracket 11.
[0030] In some embodiments, when there is enough space around the susceptor, Figure 1For the detection sensor 1 shown, increase the width W and depth L of the support 11. When the width W is greater than the wafer diameter, it can ensure that the end of the support will not collide with the wafer. The increment of the depth L can be selected as the maximum value within the possible range of the wafer protrusion. However, this modification scheme is limited by the space around the susceptor and sufficient space is required to implement it. Moreover, even if the detection sensor does not collide with the protruding dummy chip, the protruding warped dummy chip is still a potential risk to the subsequent process.
[0031] In some embodiments, the embodiment of the present application provides a wafer detector structure. Based on the original detection structure (hereinafter referred to as the first detection arm), a second detection arm is added to detect whether the wafer protrudes out of the predetermined position. The wafer detector structure includes a first detection arm and a second detection arm with relatively fixed positions. A first detection unit is provided at the end of the first detection arm; a second detection unit is provided at the end of the second detection arm. In the direction perpendicular to the wafer surface, the first detection unit and the second detection unit are separated by a first distance; in the direction parallel to the wafer surface, the first detection unit and the second detection unit are separated by a second distance, and the distance from the first detection unit to the wafer is less than the distance from the second detection unit to the wafer. The first detection unit is configured to at least detect whether there is a wafer at the predetermined position, and the second detection unit is configured to at least detect whether there is a wafer outside the predetermined position. The wafer detector structure is used for wafer position detection in batch equipment such as susceptors.
[0032] The technical solution of the present application will be described in detail below in conjunction with the embodiments and the drawings.
[0033] Figure 3 is a top view of the wafer detector structure shown in some embodiments of the present application. Figure 4 is a side view of the wafer detector structure shown in some embodiments of the present application.
[0034] Refer to Figure 3 and Figure 4 As shown, in some embodiments, the wafer detector structure 100 of the present application includes a first detection arm 110 and a second detection arm 120 with relatively fixed positions. The first detection arm 110 and the second detection arm 120 are fixed on a connecting rod 113, and the connecting rod 113 is used to connect with a moving device (not shown). A first detection unit 111 is provided at the end of the first detection arm 110; a second detection unit 121 is provided at the end of the second detection arm 120. In the direction perpendicular to the wafer 20 surface, the distance between the first detection unit 111 and the second detection unit 121 is the first distance H; in the direction parallel to the wafer 20 surface, the distance between the first detection unit 111 and the second detection unit 121 is the second distance D.
[0035] The first detection arm 110 is used to detect whether there is a wafer 20 on the placement groove of the susceptor 30. The first detection arm 110 moves along a set path, and the movement path of the first detection arm 110 is set to be able to detect the wafer 20 without colliding with the wafer 20. For example, the movement path of the first detection arm 110 is to move outside the wafer 20 and along a direction perpendicular to the surface of the wafer 20, sweeping across all the placement grooves of the susceptor 30 (i.e., the predetermined positions of the wafer 20). During this process, there are positions with the wafer 20 and positions without the wafer 20, and the feedback signals received by the first detection unit 111 are different. The first detection unit 111 can thus determine whether there is a wafer on all the placement grooves. In some embodiments, the difference in the feedback signals lies in the strength and time difference of the received signals; in other embodiments, the difference in the feedback signals lies in the presence or absence of the received signals.
[0036] Reference Figure 3 As shown in the top view of the wafer detector structure, the detection signal line 114 of the first detection unit 111 (a virtual connection line, see Figure 3 the dashed line in) extends into the vertical projection plane of the wafer 20 located at the predetermined position, and the penetration depth D1 = wafer radius - the distance from the center of the wafer circle to the detection signal line 114. D1 can be set according to the specific structure of the susceptor 30 and the surrounding space, as long as it satisfies that during the moving and scanning process of the first detection arm 110, the detection signal line 114 of the first detection unit 111 can scan the wafer 20.
[0037] When the wafer 20 (usually a dummy wafer) deviates from the predetermined position due to warping or other reasons, the protruding wafer 20 will overlap with the movement path of the first detection arm 110, causing movement interference and collision. Since there is a certain gap between the movement path of the first detection arm 110 and the predetermined position of the wafer 20, there is a maximum distance D2 at which the wafer 20 protrudes from the predetermined position but does not intersect with the movement trajectory of the first detection arm 110.
[0038] In some embodiments, as shown in Figure 3 parallel to the surface of the wafer 20, the first detection unit 111 and the second detection unit 121 are separated by a second distance D, and the distance from the first detection unit 111 to the wafer 20 is less than the distance from the second detection unit 121 to the wafer 20.
[0039] Specifically, in some embodiments, D = D1 + D2, where D1 is the depth of the first detection unit 111 (i.e., the detection signal line 114) extending into the vertical projection plane of the wafer 20, and D2 is the maximum distance that the wafer 20 protrudes from the predetermined position without intersecting the movement trajectory of the first detection arm 110. The wafer detector structure 100 initially scans the wafers in the susceptor from one end to the other end, with the second detection arm 120 in the front and the first detection arm 110 in the back. During the process of moving and scanning the wafers, when the second detection unit 121 detects a certain wafer, it means that the wafer has deviated from its predetermined position, and the wafer scanning process needs to be stopped; if the scanning process continues, the first detection arm 110 will collide with the wafer.
[0040] In addition, from the time point t1 when the second detection unit 121 detects a protruding wafer to the time point t2 when the wafer scanning process finally stops, there is a time difference T between t1 and t2, that is, the time difference T = t2 - t1. In some embodiments, as shown in Figure 4 FIG. [Reference figure number not provided in the original, assuming it's a relevant figure], in the direction perpendicular to the surface of the wafer 20, the first detection unit 111 and the second detection unit 121 are separated by a first distance H. In some embodiments, the first distance H = v * T, where v is the speed of the first detection arm 110 and the second detection arm 120 moving and scanning the wafer.
[0041] In some embodiments, the first distance H > 5 cm to ensure that there is enough time to stop the wafer scanning process when the second detection unit 121 detects a protruding wafer.
[0042] Furthermore, in some embodiments, as shown in Figure 3 FIG. [Reference figure number not provided in the original, assuming it's a relevant figure], the end of the first detection arm 110 includes a first fork 112, and the first detection unit 111 is arranged at the end of the first fork 112; the end of the second detection arm 120 includes a second fork 122, and the second detection unit 121 is arranged at the end of the second fork 122.
[0043] In some embodiments, the shapes of the first fork 112 and the second fork 122 are respectively adapted to the contour of the wafer 20 to avoid touching the wafer 20 during the process of detecting the wafer 20. Figure 3 As shown in FIG. [Reference figure number not provided in the original, assuming it's a relevant figure], both the first fork 112 and the second fork 122 are right-angled, and the right-angled fork is only an example. The first fork 112 and the second fork 122 can also be other shapes, such as arc-shaped.
[0044] In some embodiments, the first detection unit 111 and the second detection unit 121 respectively include a signal transmitting end and a signal receiving end. The signal transmitting end and the signal receiving end are respectively oppositely arranged at the tops of the two branches of the first fork 112 and the second fork 122 (the positions of the signal transmitting end and the signal receiving end can be swapped with each other, so Figure 3 andFigure 4 (not marked in the figure). The signal transmitting end is used to send a detection signal, and the signal receiving end is used to receive the detection signal. When the signal receiving end cannot receive the detection signal, it means that there is an obstacle between the signal transmitting end and the signal receiving end, which is the detected wafer in the embodiment of the present application.
[0045] In some embodiments, the signal transmitting end is a laser emitting component, and the signal receiving end is a laser receiving component. The laser has the advantage of strong anti-interference ability, making the wafer position detection more reliable.
[0046] The embodiment of the present application also provides a wafer detection device. Refer to Figure 5 , the wafer detection device includes a controller (not shown), a moving device 200, and the wafer detector structure 100 described in the above embodiment. The wafer detector structure 100 is fixedly arranged on the moving device 200, and the controller is electrically connected to the moving device 200 and the wafer detector structure 100 respectively, and is used to control the moving device 200 to drive the wafer detector structure 100 to scan the storage positions of the wafers 20 on the susceptor 30 to determine whether there are wafers at these storage positions.
[0047] Specifically, in some embodiments, the scanning movement trajectory of the wafer detection device is perpendicular to the plane of the wafer 20. Before the wafer detection device starts to work, it moves to the initial scanning position, and the initial scanning position is located at one end of the susceptor (for example, the bottom of the vertically placed susceptor). The wafer detection device scans from one end of the susceptor to the other end (for example, the top of the vertically placed susceptor). This scanning process is one scan, and the scanning process of the entire wafer can include multiple reciprocating cyclic scans. In the initial scanning movement direction ( Figure 5 in the embodiment shown, the initial scanning movement direction 40 is from the bottom 31 of the susceptor 30 towards the top), the second detection unit 121 of the wafer detector structure 100 is in front, and the first detection unit 111 of the wafer detector structure 100 is behind. The wafers that are abnormally protruding out of the predetermined position are excluded in the first round of scanning to ensure the safety of subsequent detection cycles.
[0048] In some embodiments, the wafer detection device includes a warning unit (not shown). When the second detection unit 121 detects the wafer 20, the controller stops the moving device 200 and issues an abnormal alarm through the warning unit to notify the monitoring personnel to arrive at the scene in time to eliminate the fault.
[0049] The beneficial effects that may be brought about by the embodiments of the present application include, but are not limited to: A wafer detector structure and a wafer detection device of the present application use a second detection arm to detect a wafer that protrudes abnormally from a predetermined position, ensuring that the first detection arm will not collide with the protruding wafer. Once there is a dummy wafer with a protruding position in the susceptor, the collision risk can be detected in time before the wafer detection device collides with the protruding dummy wafer, and the scanning process of the wafer detection device can be stopped, avoiding problems such as equipment damage and product wafer quality impact caused by breaking the dummy wafer.
[0050] It should be noted that the beneficial effects that may be produced by different embodiments are different. In different embodiments, the beneficial effects that may be produced may be any one or several combinations of the above, or any other beneficial effects that may be obtained.
[0051] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only an example and does not constitute a limitation to this specification. Although not explicitly stated here, those skilled in the art may make various modifications, improvements, and corrections to the present application. Such modifications, improvements, and corrections are suggested in this specification, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of the present application.
[0052] It should be noted that in the description of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be a rotational connection or a sliding connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in combination with specific situations.
[0053] In addition, when terms such as "first", "second", "third", etc. are used in the description of the present application to describe various features, these terms are only used to distinguish these features and cannot be understood as indicating or implying the relevance, relative importance, or implicitly indicating the number of the indicated features.
[0054] In addition, the specification of the present application describes exemplary embodiments by referring to idealized exemplary cross-sectional views and / or plan views and / or perspective views. Therefore, differences from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are foreseeable. Accordingly, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but should include deviations in the shapes caused by, for example, manufacturing. Thus, the regions shown in the figures are substantially schematic, and their shapes are not intended to show the actual shape of the regions of the device nor to limit the scope of the exemplary embodiments.
[0055] At the same time, the present application uses specific terms to describe the embodiments of this specification. Terms such as "an embodiment", "one embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in the present application does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application can be appropriately combined.
[0056] Similarly, it should be noted that, in order to simplify the presentation of the disclosure of the present application and thus assist in the understanding of one or more inventive embodiments, in the foregoing description of the embodiments of the present application, sometimes multiple features are grouped into one embodiment, drawing, or description thereof. However, this method of disclosure does not mean that the features required by the subject matter of the present application are more than those mentioned in the claims. In fact, the features of the embodiments are fewer than all the features of the individual embodiments disclosed above.
[0057] Finally, it should be understood that the embodiments described in the present application are only used to illustrate the principles of the embodiments of the present application. Other variations may also fall within the scope of the present application. Therefore, by way of example and not limitation, alternative configurations of the embodiments of the present application may be considered to be consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to the embodiments explicitly introduced and described in the present application.
Claims
1. A wafer detector structure for detecting the position of a wafer, characterized in that, It includes a first detection arm and a second detection arm with fixed relative positions. A first detection unit is provided at the end of the first detection arm, and a second detection unit is provided at the end of the second detection arm; in the direction perpendicular to the surface of the wafer, the first detection unit and the second detection unit are separated by a first distance; in the direction parallel to the surface of the wafer, the first detection unit and the second detection unit are separated by a second distance, and the distance from the first detection unit to the wafer is less than the distance from the second detection unit to the wafer.
2. The wafer detector structure according to claim 1, wherein The first detection unit is configured to at least detect whether there is a wafer at a predetermined position, and the second detection unit is configured to at least detect whether there is a wafer outside the predetermined position.
3. The wafer detector structure according to claim 2, wherein, The end of the first detection arm includes a first fork, and the first detection unit is provided at the end of the first fork; the end of the second detection arm includes a second fork, and the second detection unit is provided at the end of the second fork.
4. The wafer detector structure according to claim 3, wherein, The first detection unit and the second detection unit respectively include a signal transmitting end and a signal receiving end, and the signal transmitting end and the signal receiving end are respectively oppositely arranged at the tops of the two branches of the first fork and the second fork.
5. The wafer detector structure according to claim 4, wherein The signal transmitting end is a laser emitting component, and the signal receiving end is a laser receiving component.
6. The wafer detector structure according to claim 1, wherein The first distance is greater than 5 cm.
7. The wafer detector structure according to claim 2, wherein The second distance = D1 + D2, where D1 is the depth of the first detection unit extending into the vertical projection plane of the wafer located at the predetermined position, and D2 is the maximum distance that the wafer protrudes from the predetermined position but does not intersect the movement trajectory of the first detection arm.
8. A wafer detection device, characterized in that, It includes a controller, a moving device, and the wafer detector structure according to any one of claims 1 to 7. The wafer detector structure is fixedly arranged on the moving device, and the controller is electrically connected to the moving device and the wafer detector structure respectively, and is used to control the moving device to drive the wafer detector structure to scan the storage position of the wafer to determine whether there is the wafer at the storage position.
9. The wafer detection device according to claim 8, wherein, The scanning movement trajectory of the wafer detection device is perpendicular to the wafer plane; in the initial scanning movement direction, the second detection unit of the wafer detector structure is in front, and the first detection unit of the wafer detector structure is behind.
10. The wafer detection device according to claim 9, characterized in that, It includes a warning unit. When the second detection unit detects the wafer, the controller stops the moving device and issues an abnormal alarm through the warning unit.