Semiconductor process equipment, wafer position acquisition device, wafer position calibration device and method

Abstract

This application discloses semiconductor process equipment, wafer position acquisition equipment, wafer position calibration equipment, and methods thereof, and relates to semiconductor process technology. The wafer position acquisition equipment includes a mounting base including a wafer mounting surface for mounting a wafer; an optical emission assembly located directly above the wafer mounting surface for irradiating the wafer on the wafer mounting surface with an annular light beam so that the edges of the wafer fall within the irradiation range of the annular light beam; and an optical detection assembly including a photodetector array distributed below the wafer mounting surface for receiving irradiation with the annular light beam to obtain wafer contour information for indicating the position information of the wafer.

Description

Technical Field

[0001] This application belongs to the technical field of semiconductor processes, and particularly relates to semiconductor process equipment, a wafer position acquisition device, a wafer position calibration device, and a method thereof.

Background Art

[0002] A semiconductor integrated circuit integrates many devices on one chip, and the substrate on which these chips are mounted is a wafer. The wafer is formed from a single crystal silicon rod through a process including multiple steps. One of those steps is to form a notch (i.e., Notch. Also called a V-shaped groove) on the wafer using a chamfering mechanism. In national standards, the notch is defined to have a depth of 1 mm and an angle of 90°, and is a concave structure with a certain angle and depth. The function of the notch on the wafer is to identify the crystallization direction of the wafer and ensure the consistency of the direction throughout the subsequent process. Therefore, in any of a series of semiconductor processes such as lithography, etching, and deposition, there is a step of determining the direction of the wafer notch in order to calibrate the position of the wafer and ensure the consistency of the wafer direction throughout the process.

[0003] In conventional technology, mainstream wafer position calibration devices are based on single-point detection of laser light, a simple schematic diagram of which is shown in Figure 1. Here, 1 represents a mechanical support mechanism for wafer calibration, 2 is a laser light emission assembly, 3 is a laser light detection assembly, 4 is a moving mechanism, and 5 is a wafer. The conventional method rotates the wafer 5 using the moving mechanism 4, acquires single-point position data during the rotation of the wafer 5 using the laser light detection assembly 3, estimates the shape of the wafer 5 from the time and the speed of the moving mechanism 4, then confirms the center of gravity of the wafer 5 based on the estimated shape, and adjusts the position of the wafer 5 using the moving mechanism 4. Finally, proceeds to the next rotation cycle and confirms the direction of the notch 51 of the wafer 5. As can be seen from the above, conventional wafer position devices rotate the wafer 5 using the moving mechanism 4, and then estimate the shape of the wafer 5 from the position data acquired by the laser light detection assembly 3. The accuracy of this method depends heavily on the accuracy of the time and speed information of the movement, and therefore errors are likely to occur in calculating the center of gravity of the wafer 5, requiring the wafer 5 to be rotated multiple times and the center of gravity information to be constantly corrected. Furthermore, since the center of gravity of wafer 5 and the notch 51 of wafer 5 are checked separately, the wafer calibration time increases significantly. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The embodiments of this application provide semiconductor process equipment, wafer position acquisition equipment, wafer position calibration equipment and method thereof, with the aim of solving the technical problem that conventional wafer position calibration equipment spends a lot of time when performing wafer position calibration. [Means for solving the problem]

[0005] In a first embodiment, an embodiment of the present application provides a wafer position acquisition device for use in semiconductor process equipment, the wafer position acquisition device comprising: a mounting base including a wafer mounting surface for mounting a wafer; an optical emission assembly located directly above the wafer mounting surface for irradiating the wafer on the wafer mounting surface with an annular light beam so that the edges of the wafer fall within the irradiation range of the annular light beam; and an optical detection assembly including a photodetector array distributed below the wafer mounting surface for receiving the annular light beam irradiation and obtaining contour information of the wafer to indicate the position information of the wafer.

[0006] In some embodiments, the optical emission assembly includes a collimating light source and an axicon lens, the collimating light source being used to illuminate a collimated light beam of a preset diameter directly facing the center of the wafer mounting surface, and the axicon lens being positioned in the irradiation path of the collimated light beam and used to convert the collimated light beam into an annular light beam, and to reduce the width of the annular light beam to half of the preset diameter.

[0007] In some embodiments, when the annular light beam strikes the plane on which the wafer is located on the wafer mounting surface, the diameter of the wafer is greater than the inner diameter of the annular light beam and smaller than the outer diameter of the annular light beam.

[0008] In some embodiments, the wafer position acquisition device further includes a vertically adjustable bracket for supporting and securing the optical emission assembly so that the vertical distance from the optical emission assembly to the wafer on the wafer mounting surface is adjustable.

[0009] In a second embodiment, an embodiment of the present application provides a wafer position calibration apparatus for use in semiconductor process equipment, wherein the wafer position calibration system includes a controller, a moving mechanism, and the wafer position acquisition apparatus, the controller acquires wafer position information based on wafer contour information obtained by the wafer position acquisition apparatus, and controls and operates the moving mechanism based on the position information to move the wafer to a target position.

[0010] In some embodiments, the moving mechanism includes a rotating mechanism and a translation mechanism, wherein the rotating mechanism is used to rotate the mounting base, and the translation mechanism translates the wafer relative to the wafer mounting surface on the wafer mounting surface, and the controller controls the rotating mechanism to rotate the mounting base to rotate the wafer to a target position based on the position information, and controls the translation mechanism to translate the wafer to a target position based on the position information.

[0011] In some embodiments, the controller acquires wafer position information based on the wafer contour information obtained by the wafer position acquisition device, which includes the controller fitting the wafer outline curve based on the wafer contour information and determining whether the wafer outline curve is complete, and if the controller determines that the wafer outline curve is complete, determining the wafer position information based on the wafer outline curve.

[0012] In some embodiments, the controller determines the position information of the wafer based on the outline curve of the wafer, the controller determines the notch direction and center of gravity position of the wafer based on the outline curve of the wafer, and the controller determines the position information of the wafer based on the center of gravity position and the notch direction of the wafer.

[0013] In a third aspect, an embodiment of the present application provides semiconductor process equipment comprising a process chamber and a temporary wafer storage chamber communicating with the process chamber, wherein the wafer position acquisition device or the wafer position calibration device described above is provided in the temporary wafer storage chamber.

[0014] In a fourth aspect, an embodiment of the present application provides a wafer position calibration method comprising the steps of: irradiating a wafer on a wafer mounting surface with an annular light beam so that the edge of the wafer falls within the irradiation range of the annular light beam; detecting contour information of the wafer upon irradiation with the annular light beam; acquiring position information of the wafer based on the wafer contour information; and controlling the wafer to move it to a target position based on the wafer position information.

[0015] In some embodiments, the step of obtaining positional information of the wafer based on the wafer contour information includes the steps of fitting the wafer outline curve based on the wafer contour information and determining whether the wafer outline curve is complete, and if it is determined that the wafer outline curve is complete, determining the positional information of the wafer based on the wafer outline curve.

[0016] In some embodiments, the step of determining the position information of the wafer based on the outline curve of the wafer includes the steps of determining the notch direction and the center of gravity of the wafer based on the outline curve of the wafer, and determining the position information of the wafer based on the center of gravity of the wafer and the notch direction of the wafer.

[0017] In some embodiments, the step of controlling the wafer to move it to a target position based on the position information of the wafer includes the step of controlling and translating the wafer based on the center of gravity of the wafer so that the center of gravity of the wafer coincides with the center point of the wafer mounting surface, and the step of controlling the wafer mounting surface based on the notch direction of the wafer to rotate the wafer so that the notch direction of the wafer faces a target direction. [Effects of the Invention]

[0018] In this invention, the optical emission assembly of the wafer position acquisition device irradiates the wafer on the wafer mounting surface with an annular light beam so that the edges of the wafer fall within the irradiation range of the annular light beam. The optical detection assembly of the wafer position acquisition device includes a photodetector array distributed below the wafer mounting surface, and upon irradiation with the annular light beam, can obtain contour information of the wafer that indicates the position information of the wafer (including the notch direction and the center of gravity of the wafer). Furthermore, the controller of the wafer position calibration device acquires the position information of the wafer based on the contour information of the wafer, controls and operates the movement mechanism based on the position information of the wafer to move the wafer to the target position, thereby achieving wafer position calibration. Thus, in this technical solution, the entire wafer position information can be confirmed with only one irradiation detection throughout the wafer position information confirmation process, and throughout the entire position information confirmation process, the wafer does not need to move in any way, including rotation, and after the position information is confirmed, it is only necessary to move it once to the target position by the movement mechanism. Therefore, the wafer calibration time can be significantly reduced. [Brief explanation of the drawing]

[0019] The technical solutions and beneficial effects of this application will be clarified by describing in detail, in conjunction with the drawings, specific embodiments of this application. [Figure 1] This is a schematic diagram of the operation of a conventional wafer position calibration device. [Figure 2]It is a schematic diagram of the operation of the wafer position calibration device according to an embodiment of the present application. [Figure 3] It is a schematic diagram of the operation principle of the wafer position calibration device shown in FIG. 2. [Figure 4] It is a flowchart of the wafer position calibration method according to an embodiment of the present application. [Figure 5] It is a flowchart of step S130 of the wafer position calibration method shown in FIG. 4. [Figure 6] It is a flowchart of step S140 of the wafer position calibration method shown in FIG. 4.

Mode for Carrying Out the Invention

[0020] The technical solution in the embodiment of the present application will be clearly and completely described below in conjunction with the drawings. Naturally, the described embodiments are only a part, not all of the embodiments of the present application. All other embodiments obtained by those skilled in the art without creative efforts based on the embodiments of the present application shall also be included in the protection scope of the present application. Unless there is a contradiction, the following embodiments and their technical features can be combined with each other.

[0021] A semiconductor integrated circuit integrates many devices on one chip, and the substrate on which these chips are mounted is a wafer. The wafer is formed from a single crystal silicon rod through a process including a plurality of steps. One of those steps is to form a notch (i.e., Notch, also called a V-shaped groove) on the wafer using a chamfering mechanism. In national standards, the notch is defined as having a depth of 1 mm and an angle of 90°, and is a concave structure with a certain angle and depth. The function of the notch on the wafer is to identify the crystallization direction of the wafer and ensure the consistency of the direction throughout the subsequent process. Therefore, in any of a series of semiconductor processes such as lithography, etching, and deposition, there is a step of determining the direction of the wafer notch in order to calibrate the position of the wafer and ensure the consistency of the direction of the wafer throughout the process.

[0022] In the prior art, the mainstream wafer position calibration device is based on the single-point detection of laser light, and its simple schematic diagram is shown in FIG. 1. Here, 1 is a mechanical support mechanism for wafer calibration, 2 is a laser light emission assembly, 3 is a laser light detection assembly, 4 is a moving mechanism, and 5 represents a wafer. The conventional method rotates the wafer 5 by the moving mechanism 4, obtains the position data of a single point during the rotation of the wafer 5 by the laser light detection assembly 3, estimates the outer shape of the wafer 5 from the time and the speed of the moving mechanism 4, then confirms the center-of-gravity position of the wafer 5 based on the estimated outer shape, and adjusts the position of the wafer 5 by the moving mechanism 4. Finally, it proceeds to the next rotation cycle and confirms the direction of the notch 51 of the wafer 5. As can be seen from the above, the conventional wafer position device rotates the wafer 5 by the moving mechanism 4, and then estimates the outer shape of the wafer 5 from the position data obtained by the laser light detection assembly 3. The accuracy of this method greatly depends on the accuracy of the moving time and speed information. Therefore, an error is likely to occur in the calculation of the center of gravity of the wafer 5, and it is necessary to rotate the wafer 5 multiple times to continuously correct the center-of-gravity information. In addition, since the confirmation of the center of gravity of the wafer 5 and the confirmation of the notch 51 of the wafer 5 are performed separately, the calibration time of the wafer is significantly increased.

[0023] Based on this, in order to solve the technical problem that it takes a lot of time to perform wafer position calibration in the wafer position calibration device in the prior art, it is necessary to provide a solution means for a new wafer position acquisition method and a wafer position calibration method.

[0024] In one embodiment, as shown in Figures 2 and 3, an embodiment of the present application provides semiconductor process equipment comprising a process chamber (not shown) and a wafer temporary storage chamber (not shown) communicating with the process chamber, wherein a wafer position calibration device or wafer position acquisition device 100 is mounted in the wafer temporary storage chamber. The wafer position calibration device may specifically include a controller (not shown), a moving mechanism (not shown), and the wafer position acquisition device 100. The wafer position acquisition device 100 may specifically include a mounting base 110, an optical emission assembly 120, and an optical detection assembly 130. The mounting base 110 may specifically include a wafer mounting surface for mounting a wafer 200. The optical emission assembly 120 is located directly above the wafer mounting surface and is used to irradiate the wafer 200 on the wafer mounting surface with an annular light beam so that the edges of the wafer 200 fall within the irradiation range of the annular light beam. The photodetector assembly 130 may specifically include a photodetector array distributed below the wafer mounting surface, and is used to obtain contour information of the wafer 200 to indicate the position information of the wafer 200 by being irradiated with an annular light beam. The controller can acquire position information of the wafer 200 based on the contour information of the wafer 200 obtained by the wafer position acquisition device 100, and control and operate the moving mechanism based on the position information to move the wafer 200 to a target position, thereby achieving position calibration of the wafer 200. More specifically, the position information may include the notch position of the wafer 200 (i.e., the notch direction) and the position of the wafer 200 on the wafer mounting surface, and the target position may include the position where the notch of the wafer 200 should be rotated and the position of the wafer 200 on the wafer mounting surface.

[0025] To make it understandable, the wafer mounting surface of the mounting base 110 for mounting the wafer 200 is slightly smaller than the minimum wafer size, and can completely cover the wafer mounting surface when a wafer 200 of any size greater than or equal to the minimum wafer size is mounted on the wafer mounting surface. The photodetector array has a coverage area much larger than the size of the wafer 200 and is mainly located within a certain size range below the wafer mounting surface. A corresponding photodetector does not need to be provided directly below the wafer mounting surface; that is, the photodetector array is distributed in areas other than directly below the wafer mounting surface. This ensures that when the edge of the wafer 200 enters the irradiation range of the annular light beam, a portion of the annular light beam irradiates the edge of the wafer 200, and the other portion of the annular light beam irradiates the photodetector array, thereby ensuring that the photodetector array can detect and acquire contour information of the wafer 200 based on this. The controller can also acquire position information of the wafer 200 based on this contour information. The positional information may specifically include the center of gravity of the wafer 200 and the notch direction of the notch 210 of the wafer 200. The detailed detection process will be explained in more detail in the following method examples and will not be explained in detail here.

[0026] Furthermore, to better realize the installation of the photodetector array, the photodetector array can be directly distributed in a matrix across the entire upper surface of the support platform 140 of the device, or distributed in an annular array across the entire upper surface of the support platform 140 of the device. In addition, in order to reduce the measurement error of the photodetector array with respect to the position information of the wafer 200 as much as possible, it is necessary to minimize the height difference between the wafer mounting surface of the mounting base 110 and its upper surface, and to bring the surface of the wafer 200 and the surface of the photodetector array as close to the same horizontal plane as possible. Specifically, the photodetector array may be a charge-coupled device (CCD) matrix.

[0027] In this way, the optical emission assembly 120 of the wafer position acquisition device 100 can irradiate the wafer 200 on the wafer mounting surface with an annular light beam so that the edge of the wafer 200 falls within the irradiation range of the annular light beam. The optical detection assembly 130 of the wafer position acquisition device 100 includes a photodetector array distributed below the wafer mounting surface and, upon irradiation with the annular light beam, can obtain contour information of the wafer that indicates the position information of the wafer 200 (including the notch direction and the center of gravity of the wafer 200). Furthermore, the controller of the wafer position calibration device can acquire the position information of the wafer based on the contour information of the wafer, drive and operate the moving mechanism based on the position information of the wafer 200 to move the wafer 200 to the target position, thereby achieving position calibration of the wafer 200. Therefore, in this technical solution, the entire wafer position information can be confirmed with only one irradiation detection throughout the wafer position information confirmation process. Furthermore, throughout the entire position information confirmation process, the wafer 200 does not need to move in any way, including rotation. After confirming the position information, it is only necessary to move it once to the target position using a movement mechanism. Consequently, the wafer calibration time can be significantly reduced.

[0028] In some examples, as shown in Figures 2 and 3, the optical emission assembly 120 may specifically include a collimating light source 121 and an axicon lens 122, the collimating light source 121 being used to illuminate a collimated light beam having a preset diameter d1, which may be, for example, a laser light beam, directly facing the center of the wafer mounting surface. The axicon lens 122 is located in the irradiation path of the collimated light beam, and the collimated light beam acquires Bessel beam characteristics upon passing through the axicon lens 122, thereby converting the collimated light beam into an annular light beam, the width d2 of the annular light beam being half of the preset diameter d1, i.e., d2 = d1 / 2. This is because the propagation direction of the light ray changes due to the effects of refraction and reflection as the collimated light beam passes through the axicon lens 122. If the angle of incidence satisfies the requirements of the internal angle of the axicon lens 122, the light ray is reflected multiple times along the inside of the axicon lens 122, resulting in a small angular rotation. This rotation allows the direction of a beam with a very narrow lateral distribution width to be altered. As the light ray continues to reflect off the triangular surface, its trajectory gradually shifts, tracing a circle and forming an annular light spot. This phenomenon is called beam rotation or optical vortex mode. To better illuminate the collimated light beam and convert the collimated light beam into a desired annular light beam, the collimated light source 121 may be, for example, a laser, and the axicon lens 122 may be, for example, a conical lens.

[0029] In some cases, as shown in Figures 2 and 3, to ensure that the edges of the wafer 200 fall within the irradiation range of the annular light beam, the diameter of the wafer 200 must be greater than the inner diameter d3 of the annular light beam and smaller than the outer diameter d4 of the annular light beam when the annular light beam strikes the plane on which the wafer 200 is located on the wafer mounting surface. Preferably, d4 = wafer diameter + d2 is generally optimal, meaning that the edges of the wafer 200 fall within the center of the annular light beam. In this case, the width d2 of the annular light beam also determines the calibration reference value (spec value) of the wafer calibration apparatus 100. If the distance at which the center of gravity of the wafer 200 deviates from the center point of the wafer mounting surface of the mounting base 110 exceeds the reference value, it is considered necessary to calibrate the wafer position after recalibration of the work station. Specifically, the reference value is equal to half the width d2 of the annular light beam.

[0030] Furthermore, the outer diameter d4 of the annular light beam is directly proportional to the height L from the apex angle of the axicon lens 122 to the wafer 200, i.e., d3 = 2L × tan[(n-1)α] (this direct proportionality can be derived from the law of refraction and the tangent theorem. If the angle of refraction is θ and the angle of incidence is π / 2 - (π / 2 - α) = α, then nsinα = sinθ, and from the tangent theorem, d4 = 2Ltan(θ - α), and since n > 1, θ > α, so the coefficient in the linear relationship between d4 and L is positive, and these are directly proportional. Since the base angle α of the axicon lens 122 is very small, according to the small-angle approximation principle nsinα = sinθ, θ = nα).

[0031] Here, n is the refractive index of the axicon lens 122 and is related to the material of the axicon lens 122. This optical property allows for positional calibration of wafers 200 of different sizes by adjusting the height L. In this case, the wafer position acquisition device 100 further includes a vertically adjustable bracket 150 for supporting and fixing the optical emission assembly 120 so that the vertical distance from the optical emission assembly 120 to the wafer 200 on the wafer mounting surface can be adjusted, and by further changing the height L, different outer diameters d4 of the annular optical beam are formed to accommodate positional calibration of wafers 200 of different sizes. Taking a prism 122 with a refractive index n of 1.8 and an α angle of 30 degrees as an example, the laser light beam diameter is 20 mm. Using the approximate formula, we can calculate tan[(1.8-1)×30°]=0.445, d4=300 mm + 10 mm, and L=d4 / (2×0.445)≈348 mm. In other words, if the diameter of wafer 200 is 300 mm, the height L mentioned above needs to be adjusted to approximately 348 mm.

[0032] In this way, compared to conventional wafer position calibration equipment that only supports position calibration of wafers of a single size, this wafer position calibration equipment can support position calibration of wafers of different sizes without changing the calibration equipment.

[0033] In some examples, the above-described moving mechanism may specifically include a rotation mechanism and a translation mechanism. The rotation mechanism may be used to rotate the mounting base 110, that is, it acts directly on the mounting base 110 to rotate the wafer 200 on the wafer mounting surface so that the notch direction of the wafer 200 is oriented toward the target direction, and the rotation mechanism may be, for example, a motor. The translation mechanism may be used to translate the wafer 200 on the wafer mounting surface relative to the wafer mounting surface, that is, it acts directly on the wafer 200 on the wafer mounting surface, and specifically may be a robot arm provided above the wafer mounting surface, which directly grasps the wafer 200 on the wafer mounting surface and translates the wafer 200 relative to the wafer mounting surface so that the center of gravity of the wafer 200 can be aligned with the center point of the wafer mounting surface. Furthermore, the power mechanism may be located below the wafer mounting surface. This power mechanism supports the edge of the wafer 200 via a plurality of lift pins and translates the wafer 200 relative to the wafer mounting surface, thereby aligning the center of gravity of the wafer 200 with the center point of the wafer mounting surface. The controller is used to control the rotation mechanism to rotate the wafer 200 to a target position (i.e., target notch direction) by rotating the mounting base 110 based on position information (i.e., the notch direction of the wafer 200), and to control the translation mechanism to translate the wafer 200 to a target position (i.e., target center of gravity position) based on position information (i.e., the center of gravity position of the wafer 200).

[0034] In one embodiment, the present invention also provides a wafer position acquisition device for semiconductor process equipment. The structure and function of the wafer position acquisition device are specifically described by referring to the wafer position acquisition device 100 of the above embodiment and will not be described in detail here.

[0035] In one embodiment, the present invention also provides a wafer position calibration device for semiconductor process equipment. The structure and function of the wafer position calibration device will not be described in detail here, as they can be specifically described by referring to the wafer position calibration device of the above embodiment.

[0036] In one embodiment, as shown in Figure 4, the embodiment of the present application provides a wafer position calibration method, which may specifically include the following steps.

[0037] Step S110: An annular light beam is irradiated onto the wafer on the wafer mounting surface so that the edge of the wafer falls within the irradiation range of the annular light beam.

[0038] As shown in Figure 2, after the wafer 200 is mounted on the wafer mounting surface of the mounting base 110, the optical emission assembly 120 can irradiate the wafer 200 with an annular light beam so that the edges of the wafer 200 fall within the irradiation range of the annular light beam.

[0039] Furthermore, based on the above explanation, the following can be understood: To ensure that the edge of the wafer 200 falls within the irradiation range of the annular light beam, when the annular light beam strikes the plane on which the wafer 200 is located, the diameter of the wafer 200 must be greater than the inner diameter d3 of the annular light beam and smaller than the outer diameter d4 of the annular light beam. Preferably, d4 = wafer diameter + d2 is generally optimal, meaning that the edge of the wafer 200 falls within the center of the annular light beam. Also, the outer diameter d4 of the annular light beam is directly proportional to the height L from the apex angle of the axicon lens 122 to the wafer 200, i.e., d3 = 2L × tan[(n-1)α], where n is the refractive index of the axicon lens 122 and is related to the material of the axicon lens 122. This optical property allows for positional calibration of wafers 200 of different sizes by adjusting the height L. At this time, the vertical distance from the optical emission assembly 120 to the wafer 200 on the wafer mounting surface can be adjusted by the vertically adjustable bracket 150, and by changing the height L, different outer diameters d4 of the annular light beam can be formed, and furthermore, the edges of wafers 200 of different sizes can be ensured to fall within the irradiation range of the annular light beam.

[0040] Step S120: The wafer is irradiated with the annular light beam, and its contour information is detected and acquired.

[0041] To make it clear, by following the steps of the method described above, after the edge of the wafer 200 enters the irradiation range of the annular light beam, the photodetector assembly 130 can be irradiated with the annular light beam and detect and acquire the wafer contour information. Specifically, by applying data encoding to the photodetector array of the photodetector assembly, the wafer contour information can be acquired when the photodetector array is irradiated with the annular light beam.

[0042] The data encoding in this step may specifically involve forming a corresponding XY coordinate system on the surface on which the photodetector array is located. In this way, the wafer 200 partially obstructs the annular light beam, thereby forming a corresponding obstructed annular light spot on the photodetector array. The photodetector array can obtain contour information of the wafer by detecting this obstructed annular light spot. This contour information should include the coordinates of each point along the edge of the wafer 200.

[0043] Step S130: Based on the wafer contour information, the position information of the wafer is obtained.

[0044] To make it easier to understand, after obtaining the contour information of the wafer 200 by the steps of the method described above, the position information of the wafer 200 can be obtained by analyzing and calculating the contour information of the wafer 200, and this position information may specifically include the notch direction and the center of gravity position of the wafer 200.

[0045] Step S140: Based on the position information of the wafer, the wafer is controlled to move it to the target position.

[0046] To make it easier to understand, after obtaining the position information of the wafer 200 by the steps of the method described above, the wafer 200 can be controlled and moved to the target position based on the position information of the wafer 200. Specifically, this can be achieved by the moving mechanism described above, that is, the wafer 200 is driven to move by the moving mechanism so that the center of gravity of the wafer 200 coincides with the center point of the wafer mounting surface and the notch direction of the wafer 200 faces the target direction.

[0047] In this way, the technical solution of this embodiment allows for the confirmation of the entire wafer position information with only one irradiation detection throughout the wafer position information confirmation process. Furthermore, throughout the entire position information confirmation process, the wafer 200 does not need to move in any way, including rotation. After the position information is confirmed, it only needs to be moved once to the target position by the movement mechanism. Therefore, the wafer calibration time can be significantly reduced.

[0048] In some examples, the process of performing the above step of "acquiring the wafer's position information based on the wafer's contour information" in order to better verify the wafer's position information is specifically as follows:

[0049] Step S131: The outer shape curve of the wafer is fitted based on the wafer's contour information, and it is determined whether or not the outer shape curve of the wafer is complete.

[0050] It is understood that after obtaining the wafer contour information by the steps of the method described above, the wafer's outline curve can be fitted based on the wafer contour information, and it can be determined whether or not the wafer's outline curve is complete. As can be seen from the above explanation, if the distance at which the center of gravity of the wafer 200 deviates from the center point of the mounting surface of the mounting base 110 exceeds the reference value, it is considered that the work station needs to be recalibrated. Therefore, the steps of this method can confirm whether or not the distance at which the center of gravity of the wafer 200 deviates from the center point of the wafer mounting surface of the mounting base 110 exceeds the reference value by determining whether or not the wafer's outline curve is complete. This is because if the distance at which the center of gravity of the wafer 200 deviates from the center point of the wafer mounting surface of the mounting base 110 exceeds the reference value, a part of the edge of the wafer 200 will exceed the irradiation range of the annular light beam, preventing the complete contour information of the wafer 200 from being obtained, and ultimately resulting in an incomplete outline curve. Therefore, if it is determined that the wafer's outline curve is incomplete, it is necessary to recalibrate the work station and then calibrate the wafer's position.

[0051] Step S132: If it is determined that the outline curve of the wafer is complete, the position information of the wafer is determined based on the outline curve of the wafer.

[0052] To make it easier to understand, if the outline curve of the wafer is determined to be complete by the steps of the method described above, the position information of the wafer can be determined based on the outline curve of the wafer, and the specific process is as follows: First, the notch direction (i.e., the orientation of the notch 210) and the center of gravity position (i.e., the coordinate information of the center of gravity position; the center of gravity position can be specifically determined by the least squares method based on the outline curve of the wafer 200) of the wafer 200 are determined. Then, the center of gravity position and the notch direction of the wafer 200 are combined to determine the position information of the wafer 200.

[0053] In some examples, the process of performing the above step of "controlling the wafer to move it to a target position based on the wafer's position information" in order to better control the wafer's movement to a target position is specifically as follows:

[0054] Step S141: Based on the center of gravity of the wafer, the wafer is controlled and translated so that the center of gravity of the wafer coincides with the center point of the wafer mounting surface.

[0055] To make it easier to understand, as shown in Figure 2, in order to move the wafer 200 to a target position, that is, to perform position calibration of the wafer 200, it is first necessary to ensure that the center of gravity of the wafer 200 coincides with the center point of the wafer mounting surface. At this time, based on the center of gravity of the wafer 200 in the position information of the wafer 200 obtained by the steps of the above method, the wafer 200 can be controlled and translated until the center of gravity of the wafer 200 coincides with the center point of the wafer mounting surface. Specifically, it can be translated relative to the wafer mounting surface.

[0056] Step S142: Based on the notch direction of the wafer, the wafer mounting surface is controlled to rotate the wafer so that the notch direction of the wafer faces the target orientation.

[0057] As shown in Figure 2, in order to move the wafer 200 to the target position, that is, to perform position calibration of the wafer 200, the center of gravity of the wafer 200 is made to coincide with the center point of the wafer mounting surface. Then, based on the notch direction of the wafer 200 in the position information of the wafer 200 obtained by the steps of the above method, the wafer 200 is controlled to rotate, and specifically, the wafer mounting surface is controlled to rotate the wafer 200 until the notch direction of the wafer 200 faces the target direction, thereby completing the position calibration of the wafer 200.

[0058] While this application is illustrated and described with respect to one or more embodiments, equivalent changes and modifications will be apparent to those skilled in the art by reading and understanding this specification and the drawings. This application includes all such changes and modifications and is limited only by the following claims. In particular, with respect to the various functions performed by the above-described assemblies, the terminology used to describe such assemblies is intended to correspond to any assembly (unless otherwise specified) that performs a specified function (e.g., functionally equivalent) of the disclosed structure performing the function in the exemplary embodiments shown herein, even if it is not structurally equivalent to the disclosed structure performing the function.

[0059] In other words, the above description is merely an example of the present application and does not limit the scope of the patent. Equivalent structural or equivalent process transformations, such as the combination of technical features between each example or direct or indirect applications to other related technical fields, performed using the contents of the specification and drawings of the present application, are also included in the scope of the patent protection of the present application.

[0060] Furthermore, in the description of this application, directions and positional relationships indicated by terms such as "center," "vertical," "horizontal," "length," "width," "thickness," "top," "bottom," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," and "outside" are based on the directions and positional relationships shown in the drawings and are merely for the convenience and simplification of the description of this application. They do not indicate or imply that the devices or elements mentioned have a specific orientation or must be configured and operated in a specific orientation, and therefore should not be understood as limitations on this application. Moreover, structural elements having the same or similar characteristics may be identified in this application using the same or different numbers. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or the number of technical features shown. Therefore, features limited by "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more unless otherwise specified.

[0061] In this application, the word “exemplary” is used to mean “used as an example, instance, or illustration.” No embodiment described “exemplary” in this specification should be construed as necessarily preferable or advantageous to any other embodiment. The above description is provided to enable a person skilled in the art to carry out and use the present application. Various details are included in the above description for illustrative purposes. It will be apparent to a person skilled in the art that the application can be carried out without these specific details. In other embodiments, well-known structures and processes are not described in detail to avoid obscuring the description of the application by unnecessary details. Accordingly, the application is not intended to be limited to the embodiments shown, but rather to be consistent with the broadest scope of the principles and features disclosed herein.

Claims

1. A wafer position acquisition device used in semiconductor process equipment, The wafer position acquisition device is A mounting base including a wafer mounting surface for mounting wafers, A light emission assembly positioned directly above the wafer mounting surface, which irradiates the wafer on the wafer mounting surface with an annular light beam so that the edge of the wafer falls within the irradiation range of the annular light beam, A wafer position acquisition apparatus comprising a photodetector array distributed below the wafer mounting surface, and a photodetection assembly that receives irradiation from the annular light beam to obtain contour information of the wafer for indicating the position information of the wafer.

2. The aforementioned light emission assembly includes a collimated light source and an axicon lens, The collimating light source is used to irradiate the center of the wafer mounting surface with a collimating light beam of a predetermined diameter, The wafer position acquisition apparatus according to claim 1, characterized in that the axicon lens is located in the irradiation path of the collimating light beam and is used to convert the collimating light beam into an annular light beam and to reduce the width of the annular light beam to half of the preset diameter.

3. The wafer position acquisition apparatus according to claim 1 or 2, characterized in that when the annular light beam strikes the plane on which the wafer is located on the wafer mounting surface, the diameter of the wafer is greater than the inner diameter of the annular light beam and smaller than the outer diameter of the annular light beam.

4. The wafer position acquisition apparatus according to claim 1 or 2, further comprising a vertically adjustable bracket for supporting and fixing the optical emission assembly such that the vertical distance from the optical emission assembly to the wafer on the wafer mounting surface can be adjusted.

5. A wafer position calibration apparatus used in semiconductor process equipment, wherein the wafer position calibration system includes a controller, a moving mechanism, and a wafer position acquisition apparatus according to any one of claims 1 to 4. A wafer position calibration apparatus characterized in that the controller acquires wafer position information based on the wafer contour information obtained by the wafer position acquisition device, controls and operates the moving mechanism based on the position information, and moves the wafer to a target position.

6. The moving mechanism includes a rotation mechanism and a translation mechanism, the rotation mechanism being used to rotate the mounting base, and the translation mechanism being used to translate the wafer on the wafer mounting surface relative to the wafer mounting surface. The wafer position calibration apparatus according to claim 5, characterized in that the controller controls the rotation mechanism to rotate the mounting base to rotate the wafer to a target position based on the position information, and controls the translation mechanism to translate the wafer to a target position based on the position information.

7. The controller acquires the wafer position information based on the wafer contour information obtained by the wafer position acquisition device. The controller fits the outline curve of the wafer based on the wafer contour information and determines whether the outline curve of the wafer is complete or not. The wafer position calibration apparatus according to claim 5, characterized in that the controller determines, when it determines that the outline curve of the wafer is perfect, determines the position information of the wafer based on the outline curve of the wafer.

8. The controller determines the position information of the wafer based on the outer shape curve of the wafer. The controller determines the notch direction and center of gravity position of the wafer based on the outer shape curve of the wafer, The wafer position calibration apparatus according to claim 7, characterized in that the controller determines the position information of the wafer based on the center of gravity position of the wafer and the notch direction of the wafer.

9. A semiconductor process apparatus comprising a process chamber and a temporary wafer storage chamber communicating with the process chamber, wherein a wafer position acquisition device according to any one of claims 1 to 4, or a wafer position calibration device according to any one of claims 5 to 8, is provided in the temporary wafer storage chamber.

10. The steps include: irradiating the wafer on the wafer mounting surface with an annular light beam so that the edge of the wafer falls within the irradiation range of the annular light beam; The steps include detecting the contour information of the wafer upon irradiation with the aforementioned annular light beam, A step of acquiring the position information of the wafer based on the wafer contour information, A wafer position calibration method characterized by comprising the step of controlling the wafer to move it to a target position based on the wafer's position information.

11. The step of obtaining the position information of the wafer based on the wafer contour information is: The steps include fitting the outer shape curve of the wafer based on the wafer contour information and determining whether the outer shape curve of the wafer is complete, A wafer position calibration method according to claim 10, characterized by comprising the step of determining the position information of the wafer based on the outer shape curve of the wafer when it is determined that the outer shape curve of the wafer is perfect.

12. The step of determining the position information of the wafer based on the outer shape curve of the wafer is, The steps include determining the notch direction and center of gravity of the wafer based on the outer shape curve of the wafer, A wafer position calibration method according to claim 11, characterized by comprising the step of determining the position information of the wafer based on the center of gravity of the wafer and the notch direction of the wafer.

13. The step of controlling the wafer to move it to a target position based on the wafer's position information is: The steps include: controlling and translating the wafer so that the center of gravity of the wafer coincides with the center point of the wafer mounting surface, based on the center position of the wafer; A wafer position calibration method according to claim 12, characterized by comprising the step of controlling the wafer mounting surface based on the notch direction of the wafer to rotate the wafer so that the notch direction of the wafer faces a target orientation.

Images