Wafer position detection apparatus and semiconductor device

Abstract

The present application discloses a wafer position detection apparatus and a semiconductor device. A first annular slide rail and a second annular slide rail of the wafer position detection apparatus are oppositely arranged on the upper side and the lower side of a semiconductor chamber. A transmitting end of a linear sensor is in sliding connection with the first annular slide rail, and a receiving end of the linear sensor is in sliding connection with the second annular slide rail; and the orthographic projection of the transmitting end of the linear sensor on a wafer and the orthographic projection of the receiving end of the linear sensor on the wafer each are partially overlapped with the wafer. A processor is used for controlling a driver to drive the transmitting end of the linear sensor and the receiving end of the linear sensor to slide synchronously; controlling the transmitting end of the linear sensor to transmit a detection signal and the receiving end of the linear sensor to receive the detection signal which is not shielded by the wafer; and determining the position of the circle center of the wafer on the basis of the detection signal received by the receiving end of the linear sensor, wherein the detection signal can penetrate through the semiconductor chamber. The present application solves the problems that existing process chambers are difficult to seal and cooling systems are required.

Description

Wafer position detection device and semiconductor equipment Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a wafer position calibration and detection device and semiconductor equipment. Background Art

[0002] The wafer needs to be calibrated before transfer, such as center calibration, to prevent the wafer from being too deviated and causing the robot to be unable to grab it when transferring it. The position of the wafer needs to be detected before calibration.

[0003] An existing wafer position detection method has the problem that the process chamber is difficult to seal and requires a cooling system.

[0004] Summary of the Invention

[0005] In response to the above technical problems, the present application provides a wafer position detection device and semiconductor equipment, which can improve the problems of existing detection methods such as difficult sealing of the process chamber and the need for a cooling system.

[0006] To solve the above technical problems, in a first aspect, embodiments of the present application provide a wafer position detection device, which is applied to a semiconductor chamber, wherein a carrying portion for carrying a wafer is provided in the semiconductor chamber; the wafer position detection device is disposed outside the semiconductor chamber, and includes a first annular slide rail, a second annular slide rail, a linear sensor transmitting end, a linear sensor receiving end, a driver, and a processor;

[0007] The first annular slide rail and the second annular slide rail are arranged oppositely at the upper and lower sides of the semiconductor chamber;

[0008] The linear sensor transmitting end is slidably connected to the first annular slide rail, and the linear sensor receiving end is slidably connected to the second annular slide rail; and the orthographic projection of the linear sensor transmitting end on the wafer and the orthographic projection of the linear sensor receiving end on the wafer both partially overlap with the wafer;

[0009] The driver is used to drive the linear sensor transmitting end and the linear sensor receiving end to slide along the annular slide rails where they are located;

[0010] The processor is used to: control the driver to drive the linear sensor transmitting end and the linear sensor receiving end to slide synchronously along the annular slide rails on which they are located; and control the linear sensor transmitting end to transmit a detection signal, and the linear sensor receiving end to receive the detection signal that is not blocked by the wafer; determine the center position of the wafer based on the detection signal received by the linear sensor receiving end; wherein the detection signal can penetrate the semiconductor chamber.

[0011] In some embodiments, determining the center position of the wafer according to the detection signal received by the linear sensor receiving end specifically includes:

[0012] determining a contour of the wafer according to the detection signal received by the linear sensor receiving end;

[0013] At least three position points are selected on the contour, and the center position of the wafer is calculated based on the at least three position points.

[0014] In some embodiments, a notch mark is provided on the edge of the wafer, and the center angle corresponding to the notch mark is θ0; selecting at least three points on the contour and calculating the center position of the wafer based on the at least three points specifically includes:

[0015] Selecting three first position points on the contour, and calculating a first center position of the wafer based on the three first position points, wherein a center angle between any two adjacent first position points among the three first position points is 120°;

[0016] Selecting three second position points on the contour and calculating a second center position of the wafer, wherein the three second position points correspond one-to-one to the three first position points, and a center angle between each second position point and the corresponding first position point is equal to a first preset angle θ1, and θ0<θ1≤120°-θ0;

[0017] Selecting three third position points on the contour and calculating a third center position of the wafer, wherein the three third position points correspond one-to-one to the three first position points, and a center angle between each third position point and the corresponding first position point is equal to a second preset angle θ2, θ0<θ2≤120°-θ0, and θ1≠θ2;

[0018] The center position of the wafer is calculated based on two positions with the smallest difference among the first center position, the second center position and the third center position.

[0019] In some embodiments, a notch mark is provided on an edge of the wafer, and the processor is further configured to:

[0020] According to the contour, the azimuth angle of the notch mark relative to the center position of the circle is calculated.

[0021] In some embodiments, calculating the azimuth angle of the notch mark relative to the center position of the circle based on the contour specifically includes:

[0022] Determining an ideal circle according to the center position of the circle and the radius of the wafer;

[0023] Comparing the ideal circle with the contour to determine the starting position and the ending position of the notch mark;

[0024] Calculate the azimuth angle θ of the starting position relative to the center position of the circle S and the azimuth angle θ of the end position relative to the center position of the circle F ;

[0025] According to the S and the θ F Calculate the azimuth angle θ of the midpoint of the line connecting the starting position and the ending position relative to the center position of the circle M .

[0026] In some embodiments, the processor is further configured to compare the determined center position of the wafer with a pre-stored target position to determine an offset between the center position of the wafer and the target position.

[0027] In some embodiments, controlling the linear sensor receiving end to receive a detection signal that is not blocked by the wafer specifically includes:

[0028] The receiving end of the linear sensor is controlled to receive the detection signal once every time it moves a preset arc length, wherein the preset arc length is less than a preset calibration accuracy value.

[0029] In some embodiments, the linear sensor transmitting end extends radially along the first annular slide rail, and a signal transmitting position is provided every predetermined length;

[0030] The linear sensor receiving end extends radially along the second annular slide rail, and a signal receiving position is set every preset length, and the signal receiving position corresponds one-to-one with the signal transmitting position, wherein the preset length is less than the preset calibration accuracy value.

[0031] In some embodiments, the linear sensor emitting end is a linear light source;

[0032] The linear sensor receiving end is a light sensor.

[0033] In a second aspect, an embodiment of the present application provides a semiconductor device, comprising: a semiconductor chamber, a wafer transfer device, and a wafer position detection device as described in the above embodiments;

[0034] The wafer position detection device is used to detect the position of the wafer located in the semiconductor chamber;

[0035] The wafer transport device is used to transport the wafer and perform position correction on the wafer according to the detection result of the wafer position detection device.

[0036] As described above, in the wafer position detection device of the present application, the linear sensor transmitting end and the linear sensor receiving end constitute a corresponding sensor, which are respectively located on the upper and lower sides of the wafer. Since the orthographic projection of the linear sensor transmitting end on the wafer and the orthographic projection of the linear sensor receiving end on the wafer partially overlap with the wafer, the edge of the wafer can be identified. The processor controls the driver to drive the linear sensor transmitting end and the linear sensor receiving end to slide synchronously along the annular slide rails where they are located, so that the entire edge of the wafer can be scanned to determine the circumference of the wafer and then determine the center position of the wafer. The wafer position detection device of the present application, since the wafer is fixed in the semiconductor chamber, does not cause the problem of the connection part between the rotating shaft and the semiconductor chamber in the existing detection device requiring sealing treatment; since the parts connected to the semiconductor chamber do not have a motor, no cooling system assistance is required even for high-temperature wafer transmission, which reduces the difficulty of maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without inventive work.

[0038] FIG1 is a schematic structural diagram of a wafer position detection device in the related art;

[0039] FIG2 is a schematic structural diagram of a wafer position detection device provided in an embodiment of the present application;

[0040] FIG3 is a schematic structural diagram of a control system of a wafer position detection device provided in an embodiment of the present application;

[0041] FIG4 is a schematic diagram of a control flow of a processor provided in an embodiment of the present application;

[0042] FIG5 is a flow chart of a method for determining a circle center position provided in an embodiment of the present application;

[0043] FIG6 is a schematic diagram of the projection position relationship of a linear sensor transmitting end / linear sensor receiving end on a wafer provided by the present application;

[0044] FIG7 is a flow chart of a preferred method for calculating the center position of a circle provided in an embodiment of the present application;

[0045] FIG8 is a schematic diagram of taking three position points on a contour provided by an embodiment of the present application;

[0046] FIG9 is a schematic diagram of detecting the azimuth angle of a notch mark on a wafer according to an embodiment of the present application;

[0047] FIG10 is a schematic diagram of a flow chart of calculating the azimuth angle of a notch mark relative to the center position of a circle provided in an embodiment of the present application;

[0048] FIG11 is a diagram of an application scenario of a semiconductor device provided in an embodiment of the present application.

[0049] The purpose of this application, its features, and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and the accompanying text are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of this application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0050] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0051] It should be noted that, in this document, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0052] It should be further understood that the terms "comprising" and "including" indicate the presence of the described features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or", "and / or", "including at least one of the following", etc. used in this application may be interpreted as inclusive, or mean any one or any combination. For example, "including at least one of the following: A, B, C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C", and for another example, "A, B or C" or "A, B and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C". Exceptions to this definition will only occur when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way.

[0053] It should be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are merely used to distinguish information of the same type from one another. For example, first information could also be referred to as second information, and similarly, second information could also be referred to as first information without departing from the scope of this document. Depending on the context, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context indicates otherwise.

[0054] It should be understood that the terms "top", "bottom", "up", "down", "vertical", "horizontal", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0055] For ease of description, the following embodiments are all described using the orthogonal space formed by the horizontal plane and the vertical direction as an example. This premise should not be understood as a limitation to the present application.

[0056] In the related art, a wafer position detection device is shown in Figure 1, including a transparent process chamber 10a, a rotating platform 20a, a light source 30a, a light receiver 40a and a driving source 50a. The rotating platform 20a is located in the process chamber 10a and is driven to rotate by an external driving source 50a. The rotating platform 20a is used to fix the wafer 101a and drive the wafer 101a to rotate. The light source 30a and the light receiver 40a are located on the upper and lower sides of the process chamber 10a. The light source 30a projects the shadow of the wafer 101a onto one side of the light receiver 40a, and the light receiver 40a determines the edge information of the wafer 101a (such as edge image information), and calculates the center of the wafer 101a based on the determined edge information.

[0057] Since the rotating platform 20a and the driving source 50a are respectively located inside and outside the process chamber 10a, the connection part between the rotating shaft 21a of the rotating platform 20a and the process chamber 10a needs to be sealed; and for high-temperature wafer transfer, the temperature of the wafer 101a is as high as 800°C or above, which will cause the temperature of the process chamber 10a to be higher than 70°C, thereby requiring a special water cooling device, which increases the overall complexity and maintenance difficulty of the equipment.

[0058] To solve the above technical problems, please refer to Figures 2 and 3. Figure 2 is a schematic diagram of the structure of a wafer position detection device provided in an embodiment of the present application, and Figure 3 is a schematic diagram of the structure of a control system of a wafer position detection device provided in an embodiment of the present application. The wafer position detection device provided in an embodiment of the present application is applied to a semiconductor chamber 10 and is used to detect the position of a wafer 101 in the semiconductor chamber 10, wherein the wafer 101 is located on a carrier 20 in the semiconductor chamber 10. The wafer position detection device may include: a first annular slide 801, a second annular slide 802, a linear sensor transmitter 30, a linear sensor receiver 40, a driver 60, and a processing module 70.

[0059] The first annular slide rail 801 and the second annular slide rail 802 are disposed oppositely at the upper and lower sides of the semiconductor chamber 10. For example, the first annular slide rail 801 may be located above the semiconductor chamber 10, and the second annular slide rail 802 may be located below the semiconductor chamber 10; or the first annular slide rail 801 may be located below the semiconductor chamber 10, and the second annular slide rail 802 may be located above the semiconductor chamber 10.

[0060] The linear sensor transmitting end 30 is slidably connected to the first annular rail 801, and the linear sensor receiving end 40 is slidably connected to the second annular rail 802. The orthographic projections of the linear sensor transmitting end 30 and the linear sensor receiving end 40 on the wafer 101 both partially overlap with the wafer 101. It will be appreciated that the radii of the first annular rail 801 and the second annular rail 802 can be designed based on the dimensions of the wafer 101.

[0061] The driver 60 is used to drive the linear sensor transmitting end 30 and the linear sensor receiving end 40 to slide along the annular slide rails where they are located.

[0062] The processor 70 is used to: control the driver 60 to drive the linear sensor transmitting end 30 and the linear sensor receiving end 40 to slide synchronously along their respective annular slide rails; and control the linear sensor transmitting end 30 to transmit a detection signal and the linear sensor receiving end 40 to receive a detection signal that is not blocked by the wafer 101. The processor 70 is also used to determine the center position of the wafer 101 based on the detection signal received by the linear sensor receiving end 40; wherein the detection signal can penetrate the semiconductor chamber 10.

[0063] In some embodiments, the driver 60 may include a single drive source that drives the linear sensor transmitter 30 and the linear sensor receiver 40 to slide synchronously along their respective annular rails. In other embodiments, the driver 60 may include two drive sources that can each drive the linear sensor transmitter 30 and the linear sensor receiver 40 to slide synchronously along their respective annular rails. In this case, the two drive sources can achieve synchronous sliding of the linear sensor transmitter 30 and the linear sensor receiver 40 along their respective annular rails under the control of the processor 70. Furthermore, if the relative position of the linear sensor transmitter 30 and the linear sensor receiver 40 needs to be adjusted, each drive source can independently drive the linear sensor transmitter 30 or the linear sensor receiver 40 to slide along their respective annular rails under the control of the processor 70. By providing two drive sources, the relative position of the linear sensor transmitter 30 and the linear sensor receiver 40 can be adjusted, thereby reducing the installation accuracy of the relative position of the linear sensor transmitter 30 and the linear sensor receiver 40 and ensuring that the signal emitted by the linear sensor transmitter 30 can be projected onto the linear sensor receiver 40 when not blocked by the wafer.

[0064] It should be noted that the linear sensor transmitting end 30 and the linear sensor receiving end 40 are two parts of a one-dimensional sensor (linear sensor), and the two constitute a beam sensor. The linear sensor transmitting end 30 can transmit a detection signal over a certain one-dimensional length, that is, the detection signal has a certain length in a specified straight line direction, and the length extends, for example, along the radial direction of the bearing surface. In FIG2 , only two arrows are used to show the detection signals (S1 and S2) emitted by the linear sensor transmitting end 30 over a one-dimensional length, which are blocked by the wafer 101 and are not blocked by the wafer 101. When not blocked by the wafer 101, the detection signal emitted by the linear sensor transmitting end 30 can penetrate the semiconductor chamber 10 and be received by the linear sensor receiving end 40. As an example, the linear sensor transmitting end 30 can be a linear light source (one-dimensional light source), such as a linear light source formed by a plurality of LEDs or laser sensors arranged in a straight line. In this embodiment, a laser sensor is preferably used because, compared with LEDs, laser sensors are less affected by ambient light. A linear light source can transmit a light signal to the linear sensor receiving end 40. The bottom and top plates of the semiconductor chamber 10 can be made of a transparent material (such as quartz) to allow the light signal to pass through. The linear sensor receiving end 40 can include multiple sensors arranged along a straight line, each of which can receive the aforementioned signal. Each sensor can be a light sensor, such as a CCD (charge-coupled device) lens. To reduce the installation accuracy of the relative position of the linear sensor transmitting end 30 and the linear sensor receiving end 40 and ensure that the signal transmitted by the linear sensor transmitting end 30 can be projected onto the linear sensor receiving end 40 when not blocked by the wafer, the length of the linear sensor receiving end 40 can be greater than that of the linear sensor transmitting end 30. In addition, based on wafer sizes, the installation position of the linear sensor transmitting end 30 can be configured such that a portion of the transmitted detection signal (signal S1) is blocked by the wafer 101, while the remaining portion (signal S2) penetrates the semiconductor chamber 10 from the edge of the wafer 101 and is received by the linear sensor receiving end 40. It can be understood that when the linear sensor transmitting end 30 and the linear sensor receiving end 40 move synchronously for one circle, a scan of the edge of the wafer 101 can be completed.

[0065] As an example, please refer to Figure 4, which is a schematic diagram of a control flow of a processor provided in an embodiment of the present application. The processor 70 can detect the center position of the wafer 101 by executing steps S110 to S130.

[0066] S110 , controlling the driver to drive the linear sensor transmitting end and the linear sensor receiving end to slide synchronously along the respective annular slide rails.

[0067] S120 , controlling the linear sensor transmitting end to transmit a detection signal, and the linear sensor receiving end to receive the detection signal that is not blocked by the wafer.

[0068] S130 , determining the center position of the wafer according to the detection signal received by the linear sensor receiving end.

[0069] In the wafer position detection device of this embodiment, a linear sensor transmitter 30 and a linear sensor receiver 40 form a through-beam sensor, which are located on the upper and lower sides of wafer 101, respectively. Since the orthographic projections of the linear sensor transmitter 30 and the orthographic projections of the linear sensor receiver 40 on wafer 101 partially overlap with wafer 101, the edge of wafer 101 can be identified. The processor 70 controls the driver 60 to drive the linear sensor transmitter 30 and the linear sensor receiver 40 to slide synchronously along their respective annular slide rails, thereby scanning the entire edge of wafer 101 to determine the circumference of wafer 101 and further determine the center position of wafer 101. Since wafer 101 is fixed in semiconductor chamber 10, the wafer position detection device of this embodiment does not require sealing of the connection between the rotating shaft and the semiconductor chamber, as in related art detection devices. Since the components connected to semiconductor chamber 10 do not have motors, no cooling system is required even for high-temperature wafer transmission, reducing maintenance difficulty.

[0070] It is easy to understand that the above steps S110 and S120 are performed together to scan the entire edge of the wafer 101.

[0071] In one embodiment, after step S130, the processor 70 may be further configured to execute step S140.

[0072] S140 , comparing the determined center position of the wafer with a pre-stored target position to determine an offset between the center position of the wafer and the target position.

[0073] After calculating the center position of the wafer, the determined center position of the wafer can be compared with the pre-stored target position to determine the offset between the center position of the wafer and the target position, so that when the center position deviates from the target position, the subsequent wafer transmission process can calibrate the center position to the target position.

[0074] In one embodiment, please refer to FIG5 , which is a flowchart of a method for determining a circle center position provided by an embodiment of the present application. Specifically, step S130 may include:

[0075] S131 , determining the outline of the wafer according to the detection signal received by the linear sensor receiving end 40 .

[0076] For example, in an area obscured by wafer 101, linear sensor receiving end 40 receives no signal, and this area can be fed back as 0. In an area not obscured by wafer 101, linear sensor receiving end 40 receives a signal, and this area can be fed back as 1. The dividing point between 1 and 0 can be determined as the edge of wafer 101. After linear sensor transmitting end 30 and linear sensor receiving end 40 move synchronously and scan the edge of wafer 101 for one cycle, the outline of wafer 101 can be obtained.

[0077] As an example, please refer to Figure 6, which is a schematic diagram of the projection position relationship of a linear sensor transmitter / linear sensor receiver on a wafer provided by the present application. When the wafer position detection device is required to be compatible with the contour recognition of wafers with a diameter of 6 inches (radius D1 = 75mm) and 8 inches (radius D2 = 100mm), a linear sensor with a length of 55mm (including the linear sensor transmitter 30 / linear sensor receiver 40) can be used. Taking the diameter of 6 inches as an example, the projection of the linear sensor on the 6-inch wafer overlaps with the 6-inch wafer for a length L1 = 15mm, and extends beyond the edge of the 6-inch wafer for a length L2 = 40mm. When switching to an 8-inch wafer, the projection of the linear sensor on the 8-inch wafer overlaps with the 8-inch wafer for a length of 40mm, and extends beyond the edge of the 8-inch wafer for a length of 15mm. This ensures that the linear sensor can perform edge scanning and recognition on both 6-inch and 8-inch wafers, thereby determining the wafer contour.

[0078] Of course, the length of the linear sensor can be further lengthened or the radial position of the linear sensor along the wafer can be adjusted as needed to accommodate wafers of more sizes.

[0079] In order to reduce the amount of data processing, the processor 70 can control the linear sensor receiving end 40 to synchronously perform circular motion, and receive a detection signal once for each preset arc length of motion, wherein the preset arc length is less than the preset calibration accuracy value. That is, under the premise of meeting the calibration accuracy, the amount of data processing is reduced. Taking an 8-inch wafer (circumference of 628mm) and a calibration accuracy of 0.1mm as an example, 8192 points can be taken during a scan (receive signals 8192 times), and the preset arc length is 628 / 8192=0.077mm<0.1mm, which can meet the calibration accuracy requirements. The coordinates of the 8192 points on the edge of the wafer can be recorded as (X1, Y1), (X2, Y2) in sequence.......(X 8192 , Y 8192 ).

[0080] In order to meet the requirements for the recognition accuracy (calibration accuracy) of the edge of the wafer, as an example, the linear sensor transmitting end 30 extends radially along the first annular slide 801, and a signal transmitting position is set every preset length. The linear sensor receiving end 40 extends radially along the second annular slide 802, and a signal receiving position is set every preset length. The signal receiving position corresponds one-to-one with the signal transmitting position, and the two form a reflection, wherein the preset length is less than the preset calibration accuracy value. For example, taking the linear sensor receiving end 40 as an example with a length of 55mm and a calibration accuracy of 0.1mm, at least 550 signal receiving points can be arranged on the linear sensor receiving end 40, and the distance between two adjacent signal receiving points is 0.1mm, thereby meeting the requirements for the recognition accuracy of the edge of the wafer.

[0081] S132 , selecting at least three position points on the contour, and calculating the center position of the wafer based on the at least three position points.

[0082] For example, at the boundary between signal 0 and signal 1, three points corresponding to signal 1 can be selected to calculate the center of the wafer. It is understood that three non-collinear points can define a circle. Several additional points corresponding to signal 1 can be selected to verify the calculation results. Similarly, three points corresponding to signal 0 can be selected at the boundary to calculate the center of the wafer. The midpoint of the two calculated center positions can also be used as the final center position to reduce calculation errors.

[0083] Since wafers are generally provided with notch marks (flat grooves or V-grooved notches), that is, the outline of the wafer is not a complete circle, when three positions are randomly selected on the identified outline, the point at the notch mark may be selected, resulting in a large error in the calculation of the center position of the circle.

[0084] As a preferred embodiment, please refer to FIG. 7 , which is a flow chart of a preferred method for calculating the center position of a circle provided in an embodiment of the present application. Taking the center angle θ0 corresponding to the notch mark as an example, the method for calculating the center position of the circle in step S132 may include:

[0085] S1321. Select three first position points on the contour and calculate the first center position of the wafer, wherein the center angle between any two adjacent first position points among the three first position points is 120°.

[0086] Please refer to FIG8 , which is a schematic diagram of taking three position points on a contour provided by an embodiment of the present application. It can be understood that a first position point is selected every 120° on the contour, and the first center position can be calculated through the three first position points. The coordinates of the three first position points are respectively: A1(X1 1,Y 1 1) A2(X 1 2,Y 1 2) A3(X 1 3,Y 1 3), the corresponding first circle center position A 1 0 coordinate is (X 1 0,Y 1 0), the coordinates of the first circle center position A0 can be calculated according to the following equations (1) to (3). (X 1 1-X 1 0) 2 +(Y 1 1-Y 1 0) 2 =R 2 (1) (X 1 2-X 1 0) 2 +(Y 1 2-Y 1 0) 2 =R 2 (2) (X 1 3-X 1 0) 2 +(Y 1 3-Y 1 0) 2 =R 2 (3)

[0087] S1322. Select three second position points on the contour and calculate the second center position of the wafer, wherein the three second position points correspond one-to-one to the three first position points, and the center angle between each second position point and the corresponding first position point is equal to the first preset angle θ1, and θ0<θ1≤120°-θ0.

[0088] It can be understood that the three second position points are equivalent to the points obtained by rotating the three first position points by a certain angle θ1. Since θ0 is generally less than 2°, θ1 is usually greater than 2° and less than 118°. For example, the first preset angle θ1 can be 45°, which is equivalent to rotating the first position point A1 (as the origin, 0° position) by 45°, 165°, and 285° and selecting three second position points from the corresponding positions on the contour.

[0089] According to the three second position points, the second center position A of the wafer can be calculated 2 0 coordinate is (X 2 0,Y 2 0), the specific calculation method can be referred to above and will not be described here.

[0090] S1323. Select three third position points on the contour and calculate the third center position of the wafer, wherein the three third position points correspond one-to-one to the three first position points, and the center angle between each third position point and the corresponding first position point is equal to the second preset angle θ2, θ0<θ2≤120°-θ0, and θ1≠θ2.

[0091] The specific embodiment of step S1323 can refer to the embodiment of step S1322, except that the second preset angle θ2 is different. For example, θ2 can be 90°. After rotating 90°, 210°, and 330° from the first position point A1 (as the origin, 0° position), three third position points are selected from the corresponding positions on the contour, and the third center position A of the wafer is calculated. 3 0 coordinate is (X 3 0,Y 3 0).

[0092] S1324. Calculate the center position of the wafer using the two positions with the smallest difference among the first center position, the second center position, and the third center position.

[0093] It can be understood that the center of the circle calculated three times in this embodiment satisfies θ0<(θ1,θ2)≤120°-θ0, and θ1≠θ2, because the angle θ1 of the second position point rotation and the angle θ2 of the third position point rotation satisfy θ0<(θ1,θ2)≤120°-θ0, and θ1≠θ2. This ensures that among the three selected position points, at least two selected position points can avoid the notch mark of the wafer, so that the center of the wafer obtained by the two calculation results basically coincides, and the center position of the wafer can be calculated using the two positions with the smallest difference.

[0094] Therefore, the distances between the first, second, and third center positions can be calculated, and the center position of the wafer can be calculated using the two positions with the smallest distance. For example, when the distance between the first and second center positions is the smallest, the first center position can be used as the center position of the wafer, the second center position can be used as the center position of the wafer, or the midpoint between the first and second center positions can be used as the center position of the wafer. This embodiment uses the method of calculating the center position three times to avoid excessive errors in the calculation of the center position.

[0095] In one embodiment, the processor is further configured to execute step S133.

[0096] S133. Calculate the azimuth angle of the notch mark relative to the center of the circle based on the contour.

[0097] Taking the notch mark of a flat groove as an example, the intersection of the symmetry axis of the notch mark and the contour is used as the reference position for calculating the azimuth angle of the notch mark. Please refer to Figure 9, which is a schematic diagram of detecting the azimuth angle of the notch mark of a wafer provided by an embodiment of the present application. For the flat groove in Figure 9, the reference position of the notch mark is point E, and the azimuth angle of the notch mark relative to the center position is θ M θ can be calculated based on the identified contour M .

[0098] As an example, please refer to Figure 10, which is a flowchart of calculating the azimuth angle of the notch mark relative to the center position of the circle provided in an embodiment of the present application. Step S133 may include the following steps S1331 to S1334.

[0099] S1331. Determine an ideal circle based on the center position of the circle and the radius of the wafer.

[0100] Since the wafer radius is known and the wafer center position has been calculated, the ideal circle corresponding to the wafer can be determined. The ideal circle is a complete circle corresponding to the outline (without the wafer notch). Based on the calculated center position and the wafer radius, the arc corresponding to the notch can be restored to obtain the coordinate data M0 of the entire ideal circle.

[0101] S1332. Compare the ideal circle with the contour to determine the starting position and the ending position of the notch mark.

[0102] For example, the coordinate data M0 of the ideal circle and the coordinate data M1 of the contour can be ANDed (the boundary is considered as "1"), and the starting point and the ending point of the gap mark can be determined according to the result of the operation, taking a clockwise operation as an example.

[0103] For position C, due to the existence of the gap mark, the result of the "AND" operation changes from 1 to 0, so it can be determined that position C is the starting point of the gap mark (X 1c ,Y 1c ).

[0104] For position D, due to the existence of the gap mark, the result of the "AND" operation changes from 0 to 1, and it can be determined that position D is the end point of the gap mark (X 1d ,Y 1d ).

[0105] S1333, calculate the azimuth angle θ of the starting position relative to the center position S and the azimuth angle θ of the end position relative to the center of the circle F .

[0106] Assuming the azimuth angle of position B relative to the center O in Figure 9 is 0°, the azimuth angles θ of the starting point C and the ending point D relative to the center O can be calculated based on their coordinates. S and θ F .

[0107] S1334, according to θ S and θ F Calculate the azimuth angle θ of the midpoint of the line connecting the starting position and the ending position relative to the center of the circle M .

[0108] Specifically, the azimuth angle of the midpoint E of the line connecting the starting position C and the ending position D relative to the center of the circle is: M =(θ S +θ F ) / 2.

[0109] Determining the azimuth angle of the wafer notch can facilitate subsequent accurate wafer transfer.

[0110] The present application also provides a semiconductor device comprising a semiconductor chamber 10, a wafer transfer device, and a wafer position detection device as described in the above embodiments. The wafer position detection device is used to detect the position of a wafer within the semiconductor chamber 10; the wafer transfer device is used to transfer the wafer and perform position correction on the wafer based on the detection results of the wafer position detection device.

[0111] For example, referring to FIG. 2 and FIG. 3 , the wafer transfer device may include a robot arm 50 , and the processor 70 may control the robot arm 50 to grab the wafer 101 from the carrier 20 of the semiconductor chamber 10 .

[0112] In one embodiment, when the center position of the wafer calculated by the processor 70 deviates from the pre-stored target position by more than a preset position threshold, the processor 70 may control the robot 50 to calibrate the center position to the target position. For example, the robot may adjust the X and Y positions of the wafer 101 in the XY horizontal plane.

[0113] In one embodiment, when the azimuth angle of the notch mark relative to the center position calculated by the processor 70 deviates from the target angle by more than a preset angle threshold, the processor 70 can control the robot 50 to calibrate the azimuth angle of the notch mark to the target angle. For example, when the target angle of the notch mark is 0° (see FIG8 ), the robot 50 can be controlled to rotate the wafer -θ M , that is, counterclockwise rotation θ M In addition to performing a translation operation on the wafer to calibrate the center position, the robot 50 can also perform a rotation operation to calibrate the angle of the notch mark.

[0114] Please refer to Figure 11, which is an application scenario diagram of a semiconductor device provided in an embodiment of the present application, which includes a material box lifting system 100, an isolation chamber 200, a transfer chamber 300 and a process chamber 400 in sequence. The semiconductor chamber 10 and the wafer position detection device of the above embodiment are arranged in the isolation chamber 200.

[0115] The cassette lift system 100 is used to transport wafer cassettes containing wafers. A robotic arm can transfer the wafers from the cassette to the semiconductor chamber 10, where the wafer position and angle are detected by a wafer position detection device. A robotic arm 50 in the transfer chamber 300 can grab wafers from the semiconductor chamber 10, calibrate their position and angle based on the detection results from the wafer position detection device, and then sequentially transfer them to the transfer chamber 300 and process chamber 400. To improve efficiency, multiple process chambers 400 can be arranged around the transfer chamber 300.

[0116] For other working principles and processes of the semiconductor device of this embodiment, please refer to the description of the wafer position detection device in the aforementioned embodiment of the present invention, which will not be repeated here.

[0117] The above describes in detail the wafer position detection device and semiconductor device provided by this application. This article uses specific examples to illustrate the principles and implementation methods of this application. It should be noted that in this application, the descriptions of each embodiment have their own emphasis. For parts not detailed or recorded in a particular embodiment, please refer to the relevant descriptions of other embodiments.

[0118] The various technical features of the technical solution of this application can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

Claims

1. A wafer position detection device, applied to a semiconductor chamber, characterized in that: The semiconductor chamber is provided with a carrying portion for carrying a wafer; the wafer position detection device is arranged outside the semiconductor chamber, and the wafer position detection device includes a first annular slide rail, a second annular slide rail, a linear sensor transmitting end, a linear sensor receiving end, a driver and a processor; The first annular slide rail and the second annular slide rail are arranged oppositely at upper and lower sides of the semiconductor chamber; The linear sensor transmitting end is slidably connected to the first annular slide rail, and the linear sensor receiving end is slidably connected to the second annular slide rail; and the orthographic projection of the linear sensor transmitting end on the wafer and the orthographic projection of the linear sensor receiving end on the wafer both partially overlap with the wafer; The driver is used to drive the linear sensor transmitting end and the linear sensor receiving end to slide along the respective annular slide rails; The processor is used to: control the driver to drive the linear sensor transmitting end and the linear sensor receiving end to slide synchronously along the annular slide rails where they are located; and control the linear sensor transmitting end to transmit a detection signal, and the linear sensor receiving end to receive the detection signal that is not blocked by the wafer; determine the center position of the wafer according to the detection signal received by the linear sensor receiving end; wherein the detection signal can penetrate the semiconductor chamber.

2. The wafer position detection device according to claim 1, characterized in that: Determining the center position of the wafer according to the detection signal received by the linear sensor receiving end specifically includes: Determining the outline of the wafer according to the detection signal received by the linear sensor receiving end; At least three position points are selected on the contour, and the center position of the wafer is calculated based on the at least three position points.

3. The wafer position detection device according to claim 2, characterized in that: The edge of the wafer is provided with a notch mark, and the center angle corresponding to the notch mark is θ0; selecting at least three position points on the contour, and calculating the center position of the wafer according to the at least three position points, specifically includes: Selecting three first position points on the contour, and calculating the first center position of the wafer according to the three first position points, wherein the center angle between any two adjacent first position points among the three first position points is 120°; Selecting three second position points on the contour, and calculating the second center position of the wafer, wherein the three second position points correspond to the three first position points one by one, and the center angle between each second position point and the corresponding first position point is equal to a first preset angle θ1, and θ0<θ1≤120°-θ0; Selecting three third position points on the contour, and calculating the third center position of the wafer, wherein the three third position points correspond to the three first position points one by one, and the center angle between each third position point and the corresponding first position point is equal to a second preset angle θ2, θ0<θ2≤120°-θ0, and θ1≠θ2; The center position of the wafer is calculated based on the two positions with the smallest difference among the first center position, the second center position and the third center position.

4. The wafer position detection device according to claim 2, characterized in that: The edge of the wafer is provided with a notch mark, and the processor is further used for: According to the contour, the azimuth angle of the notch mark relative to the center position of the circle is calculated.

5. The wafer position detection device according to claim 4, characterized in that: The step of calculating the azimuth angle of the notch mark relative to the center position of the circle according to the contour specifically includes: Determining an ideal circle according to the center position of the circle and the radius of the wafer; The ideal circle is compared with the contour to determine the starting and ending positions of the notch mark. Stop position; Calculate the azimuth angle θ of the starting position relative to the center position of the circle S and the azimuth angle θ of the end position relative to the center position of the circle F ; According to the S and the θ F Calculate the azimuth angle θ of the midpoint of the line connecting the starting position and the ending position relative to the center position of the circle M .

6. The wafer position detection device according to any one of claims 1 to 5, characterized in that: The processor is further configured to compare the determined center position of the wafer with a pre-stored target position to determine an offset between the center position of the wafer and the target position.

7. The wafer position detection device according to any one of claims 1 to 5, characterized in that: Controlling the linear sensor receiving end to receive the detection signal that is not blocked by the wafer; specifically comprising: The linear sensor receiving end is controlled to receive the detection signal once every time it moves a preset arc length, wherein the preset arc length is less than a preset calibration accuracy value.

8. The wafer position detection device according to claim 7, characterized in that: The linear sensor transmitting end extends along the radial direction of the first annular slide rail, and a signal transmitting position is set every preset length; The linear sensor receiving end extends radially along the second annular slide rail, and a signal receiving position is set every preset length, and the signal receiving position corresponds one-to-one with the signal transmitting position, wherein the preset length is less than the preset calibration accuracy value.

9. The wafer position detection device according to any one of claims 1 to 5, characterized in that: The linear sensor transmitting end is a linear light source; The linear sensor receiving end is a light sensor.

10. A semiconductor device, characterized in that: include: A semiconductor chamber, a wafer transfer device, and a wafer position detection device as claimed in any one of claims 1 to 9; The wafer position detection device is used to detect the position of the wafer located in the semiconductor chamber; The wafer transport device is used to transport the wafer and perform position correction on the wafer according to the detection result of the wafer position detection device.

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