Three-dimensional shape measurement system using deflection measurement method without gravity error

Abstract

The present invention relates to a freeform surface three-dimensional shape measurement system using a vertical deflection measurement method from which a gravitational error is removed and, more specifically, to a freeform surface three-dimensional shape measurement system using a vertical deflection measurement method from which a gravitational error is removed, the system comprising: a chuck support on which a wafer is mounted; a motion stage changing the angle of the chuck support; a first preform for measuring the shape of one side of the wafer in a state in which the planar direction of the wafer is parallel to the vertical direction; and a second preform for measuring the shape of the other side of the wafer in a state in which the planar direction of the wafer is parallel to the vertical direction, wherein the wafer is mounted on the chuck support in a state in which the planar direction of the wafer is horizontal, and the chuck support is rotated by a first rotating means of the motion stage to change the angle so that the planar direction of the wafer is parallel to the vertical direction in a measurement mode.

Description

3D shape measurement system using a bias measurement method with gravity error eliminated

[0001] The present invention relates to a freeform surface three-dimensional shape measurement system and measurement method using a vertical deflection measurement method that eliminates gravity error.

[0002] Generally, a moiré measurement system can measure a three-dimensional shape by irradiating a light source onto an object (inspection target) through a projection grating and a projection lens, and then forming an image of the irradiated object onto a reference grating using the projection grating and acquiring the formed image with a camera.

[0003] Here, Moire refers to an interference pattern formed by the overlapping of two or more periodic wave patterns, and can refer to the geometric shape that appears when photographing an object with a continuous pattern.

[0004] Figure 1 is a schematic diagram showing a general moiré-type three-dimensional shape measuring device.

[0005] Referring to FIG. 1, a 3D shape measuring device using a Moire method can generally be composed of a grid projection unit consisting of a light source, an illumination lens, a projection grid, and a projection lens to project a grid image onto the surface of an object to be inspected; an object unit consisting of an object to be inspected and an xy transfer table for mounting the object to be inspected and moving the object to be inspected along the xy plane; and an imaging unit consisting of an imaging lens and a camera for forming a grid image reflected by the surface of the object to be inspected.

[0006] Figure 2 is a drawing showing an example of a moiré pattern on the surface of an object to be inspected, onto which a general grid image is projected.

[0007] Referring to FIG. 2, a Moire fringe, which is a grid image deformed and reflected by irregularities on the surface of an object to be inspected, can be obtained as an image through the Moire method 3D shape measuring device of FIG. 1, or a reference grating can be additionally provided in the imaging unit to obtain a Moire interference fringe, which is the result of interference between the grid image reflected by the surface of the object to be inspected and the provided reference grating.

[0008] For example, when the surface of the object to be inspected is flat, an image of a grid-shaped moiré pattern without deformation is obtained as shown in Fig. 2(a), and when the surface of the object to be inspected has irregularities, an image of a grid-shaped moiré pattern deformed according to the shape of the irregularities is obtained as shown in Fig. 2(b) or Fig. 2(c). Three-dimensional shape information regarding the surface irregularities of the object to be inspected can be extracted from these moiré patterns.

[0009] However, to extract three-dimensional shape information of the surface of an object under inspection from moiré patterns or moiré interference pattern images, it is necessary to acquire moiré patterns or moiré interference pattern images for projection gratings with at least three different phases. Typically, to change the phase of the projection grating, a projection grating micro-transfer device is used to move the projection grating in the direction of the grating plane by 1 / 4, 2 / 4, or 3 / 4 cycles. This process is called phase shifting.

[0010] Figure 3 is a conceptual diagram showing the measurement of a large-area inspection target in a general moiré 3D shape measuring device.

[0011] Referring to FIG. 3, an area camera has been primarily used to acquire images of moiré patterns or moiré interference patterns (the result of interference between the image of the projection grid and the reference grid) in a moiré 3D shape measuring device. Accordingly, the size (range) of the object to be measured at once without moving the three components constituting the measuring device may be limited by the field of view of the imaging unit or the size of the projection area of ​​the grid projection unit, which are given by the magnification of the imaging lens and the size of the imaging element embedded in the area camera.

[0012] Therefore, to measure a large-area inspection target, the range of the inspection target that can be measured at once, which is limited by the field of view, must be measured; then, the grid projection unit and the imaging unit must be moved simultaneously by the same amount as the range of the inspection target that can be measured at once, and the remaining area of ​​the inspection target must be measured sequentially. At this time, the measurement process may also be repeated by moving only the inspection target in the same manner.

[0013] As illustrated in FIG. 3, if the range of the square indicated by the dotted line is defined as the range of the inspection object that can be measured at once, then an image of the area corresponding to the dotted square (a) is acquired, and then images are acquired by changing the measurement area in the order of the dotted squares (b), (c), and (d), thereby acquiring an image of the moiré pattern of the entire inspection object.

[0014] Furthermore, a freeform surface refers to an arbitrary surface that possesses asymmetry with respect to any axis, and core components of cutting-edge optical devices, such as recently introduced smart glasses and Head Mounted Displays (HMDs), are all composed of freeform surfaces. Since these freeform surfaces can overcome the limitations of optical performance in conventional optical systems composed solely of spherical or aspherical surfaces while simultaneously satisfying design requirements, extensive research is being conducted worldwide. Deflection measurement is a representative technology capable of measuring the three-dimensional shape of such freeform surfaces; unlike conventional interferometers, it is gaining attention as a next-generation freeform surface shape measuring instrument because it enables the measurement of the object's three-dimensional shape without a separate reference plane.

[0015] The basic principle of the deflection measurement method is to measure the change in slope of each surface by analyzing the phase of the pattern deformed by the shape of the object after a periodic striped pattern is incident on the surface of the object to be measured. That is, assuming the shape of the object to be measured is z=z(x,y), the measurement values ​​obtained through the deflection measurement method yield a slope component in the x-axis direction (∂z / ∂x) and a slope component in the y-axis direction (∂z / ∂y), respectively, depending on the direction of the incident pattern. Therefore, by integrating the two slope components in the x-axis and y-axis directions obtained from the measured phase, the three-dimensional shape of the object to be measured can be reconstructed.

[0016] First, FIG. 4 illustrates a schematic diagram of a three-dimensional shape measurement system using a phase-shifting shape measurement method. The pattern generation unit is a screen (10) of a display device, and the generated sinusoidal pattern is projected onto a measurement target (1).

[0017] Then, the pattern reflected from the object to be measured (1) is incident on a detector composed of a camera (20) to obtain image data having intensity and light quantity information.

[0018] In addition, the analysis means obtains a 3D shape of the object to be measured (1) by measuring and analyzing the phase from the deformed pattern measured by the camera (20). In addition, the control unit is connected to both the screen (10) and the camera (20) to control them.

[0019] Basically, an image is acquired from the detector (20), and a wrapped phase for each frequency is acquired through a Fourier transform on this pattern, and an unwrapped phase is acquired from the wrapped phase to measure and analyze the shape of the object to be measured having a freeform surface.

[0020] In a three-dimensional shape measurement system using such a phase-shifting shape measurement method, in order to measure both sides of an object to be measured, one side is measured by an arm, then flipped over and remounted on a frame to measure the other side.

[0021] FIGS. 5 and 6 illustrate a schematic diagram and a photograph of a system for measuring both sides of a wafer with a three-chip structure. FIG. 7 is the measurement result data. As shown in FIGS. 5 and 6, it can be seen that a wafer chuck, with the wafer fixed to the entire frame, is fixed so that the planar direction is horizontal, and an upper preform is provided on the upper side of the frame and a lower preform on the lower side.

[0022] A pattern generated by a pattern generating unit is projected onto a measurement target (1) on each of the upper preform and the lower preform, and the pattern reflected from the measurement target (1) is incident on a detector composed of a camera (20) to obtain image data having intensity and light quantity information.

[0023] In other words, the upper preform measures one side of the wafer, and the lower preform measures the warpage on the other side of the wafer.

[0024] At this time, the three-chip structure has the disadvantage that the wafer's warpage tendency is affected by gravity. In other words, an error occurs where the chip position is measured too high.

[0025] Therefore, the development of new measuring equipment capable of preventing measurement errors caused by the influence of gravity was required.

[0026] Accordingly, the present invention has been devised to solve the aforementioned conventional problems, and according to an embodiment of the present invention, the purpose is to provide a freeform surface 3D shape measurement system and measurement method using a vertical deflection measurement method that eliminates gravity error, which allows for the wafer chuck to be rotated within a single measurement frame without the need to attach or detach the wafer via an arm after measuring one side of the wafer, or for both sides to be measured accurately without gravity error.

[0027] Meanwhile, the technical problems to be solved by the present invention are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

[0028] The first objective of the present invention can be achieved as a three-dimensional shape measurement system using a vertical deflection measurement method that eliminates gravity error, comprising: a chuck support on which a wafer is mounted; a motion stage for changing the angle of the chuck support; a first preform for measuring the shape of one side of the wafer when the planar direction of the wafer is parallel to the vertical direction; and a second preform for measuring the shape of the other side of the wafer when the planar direction of the wafer is parallel to the vertical direction; wherein the wafer is mounted on the chuck support in a state where the planar direction of the wafer is horizontal, and the angle is changed so that the planar direction of the wafer becomes parallel to the vertical direction during the measurement mode by rotating the chuck support by a first rotation means of the motion stage.

[0029] For the first purpose, each of the first preform and the second preform may be characterized by comprising: a pattern generating unit that generates a pattern and projects it onto a measurement target; and a detector that acquires image data of a deformed pattern reflected from the measurement target.

[0030] The second objective of the present invention can be achieved as a three-dimensional shape measurement system using a vertical deflection measurement method that eliminates gravity error, comprising: a chuck support on which a wafer is mounted; a motion stage that changes the angle of the chuck support and rotates the chuck support around a vertical axis; a preform for measuring the shape of the wafer when the planar direction of the wafer is parallel to the vertical direction; and a wafer mounted on the chuck support in a state where the planar direction of the wafer is horizontal, and the chuck support is rotated by a first rotation means of the motion stage to change the angle so that the planar direction of the wafer is parallel to the vertical direction during measurement mode, thereby measuring one side of the wafer through the preform, and then the chuck support is rotated 180 degrees around the vertical axis by a second rotation means, and the other side of the wafer is measured through the preform.

[0031] For the second purpose, the preform may be characterized by comprising: a pattern generating unit that generates a pattern and projects it onto a measurement target; and a detector that acquires image data of a deformed pattern reflected from the measurement target.

[0032] For the first and second purposes, the chuck support may be characterized by including a mounting hole, which is a space for installing a wafer, a plurality of chucks, a wafer fixing part for fixing the wafer after mounting the wafer on the chuck, and a connecting end, the ends of which are hinge-connected to each of the frames of the motion stage.

[0033] For the first purpose, the motion stage may be characterized by comprising a base, a horizontal frame disposed on the base, and a vertical frame vertically connected upward from each end of the horizontal frame, wherein the chuck support is hinge-connected between a pair of vertical frames through a connecting end, and the first rotation means is driven to rotate the chuck support with respect to the hinge.

[0034] For the first purpose, the motion stage may be characterized by including a driving unit that moves the horizontal frame linearly in the forward and backward horizontal directions.

[0035] In the second purpose, the motion stage comprises a base, a stage disposed on the base, a horizontal frame, a vertical frame vertically connected upward from each end of the horizontal frame, and a second rotation means provided between the stage and the horizontal frame to rotate the chuck support with respect to a vertical axis, wherein the chuck support is hinge-coupled between a pair of vertical frames through a connecting end, and the first rotation means is driven to rotate the chuck support with respect to the hinge.

[0036] And for the second purpose, the motion stage may be characterized by including a driving unit that moves the stage linearly in the forward and backward horizontal directions.

[0037] The third objective of the present invention can be achieved as a three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, wherein, in the first objective mentioned above, at least one of the first preform and the second preform is composed of a moiré measurement unit, and the moiré measurement unit comprises: a moiré pattern generating unit that generates a moiré pattern and projects it onto a measurement target; and a moiré detector that acquires image data of a deformed moiré pattern reflected from the measurement target.

[0038] According to the freeform surface 3D shape measurement system and measurement method using a vertical deflection measurement method that eliminates gravity error according to an embodiment of the present invention, after measuring one side of a wafer, the wafer chuck can be rotated within a single measurement frame without the need to attach or detach the wafer through an arm, or both sides can be accurately measured simultaneously without gravity error.

[0039] Meanwhile, the effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

[0040] FIG. 1 is a schematic diagram showing a general moiré-type three-dimensional shape measuring device,

[0041] FIG. 2 is a drawing showing an example of a moiré pattern on the surface of an inspection object onto which a general grid image is projected.

[0042] FIG. 3 is a conceptual diagram showing the measurement of a large-area inspection target in a general moiré 3D shape measuring device,

[0043] FIG. 4 is a three-dimensional shape measurement system using a phase-shifted shape measurement method,

[0044] Figures 5, 6, and 7 show a schematic diagram, a photograph, and measurement result data of a system for measuring both sides of a wafer with a three-chip structure.

[0045] FIG. 8 is a schematic diagram of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention.

[0046] FIG. 9 is a configuration diagram and photograph of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention.

[0047] FIG. 10 is measurement result data of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention,

[0048] FIGS. 11a to 11f are a perspective view, side view, front view, rear view, and top view of a motion stage according to an embodiment of the present invention.

[0049] FIG. 12 is a schematic diagram of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to a second embodiment of the present invention.

[0050] FIGS. 13a to 13f are a perspective view, side view, front view, rear view, and top view of a motion stage according to an embodiment of the present invention.

[0051] FIG. 14 illustrates a schematic diagram of a freeform surface three-dimensional shape measurement system using a vertical deflection measurement method with gravity error removed according to the third embodiment of the present invention.

[0052] Below, the configuration, function, and measurement method of a three-dimensional shape measurement system using a bias measurement method that eliminates gravity error according to an embodiment of the present invention will be described.

[0053] FIG. 8 illustrates a schematic diagram of a freeform surface three-dimensional shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention.

[0054] FIG. 9 shows a configuration diagram and photograph of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention, and FIG. 10 shows measurement result data of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention.

[0055] FIGS. 11a to 11f illustrate a perspective view, side view, front view, rear view, and top view of a motion stage according to an embodiment of the present invention.

[0056] A freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to an embodiment of the present invention is composed of a chuck support (30), a motion stage (100), a first preform, and a second preform.

[0057] The chuck support (30) is configured in the form of a ring plate having mounting holes for mounting a wafer (1) which is a measurement target, and is configured to mount the wafer (1) through three chucks (31).

[0058] In addition, this chuck support (30) is installed on the motion stage (100). The motion stage (100) is configured to change the angle of the chuck support (30).

[0059] This motion stage (100) is positioned between the first preform and the second preform.

[0060] The first preform is configured to measure the shape of one side of the wafer (1) when the planar direction of the wafer (1) is parallel to the vertical direction.

[0061] In addition, the second preform is configured to measure the shape of the other side of the wafer (1) while the planar direction of the wafer (1) is parallel to the vertical direction.

[0062] In an embodiment of the present invention, the wafer (1) is mounted on the chuck support (30) with the planar direction of the wafer in a horizontal direction.

[0063] After the wafer (1) is installed in a horizontal direction, the chuck support (30) is rotated by the first rotation means (140) of the motion stage (100) to change to a measurement mode, thereby changing the angle so that the planar direction of the wafer (1) becomes parallel to the vertical direction during the measurement mode.

[0064] In this measurement mode, the wafer (1) is positioned vertically to measure both sides simultaneously, and the error caused by gravity is eliminated.

[0065] A first preform according to an embodiment of the present invention includes a first pattern generating unit (11) that generates a pattern and projects it onto one side of a wafer (1), and a first detector (21) that acquires image data of a deformed pattern reflected from one side of the wafer (1). A second preform also includes a second pattern generating unit (12) that generates a pattern and projects it onto the other side of the wafer (1), and a second detector (22) that acquires image data of a deformed pattern reflected from the other side of the wafer (1).

[0066] And the chuck support (30) has a mounting hole, which is a space for installing a wafer (1), as shown in FIGS. 11a to 11b, and is configured to have three chucks (31) inside the mounting hole so as to be able to mount the wafer (1).

[0067] In addition, the wafer fixing part (33) is configured in a cylinder shape to fix the wafer (1) after mounting the wafer (1) on the chuck (31). Also, the chuck support (30) may be equipped with a wafer detector (34) that detects whether the wafer (1) is mounted.

[0068] And connecting ends (32) are provided at both ends of the chuck support (30) so that they can be hinge-connected to each frame of the motion stage (100).

[0069] The frame of the motion stage (100) according to an embodiment of the present invention has a form in which a horizontal frame (120) and a pair of vertical frames (130) are connected. As shown in FIGS. 11a and 11b, it can be seen that the frame is configured to include a base (110), a horizontal frame (120), a driving unit (150), a pair of vertical frames (130), a first rotation means (140), etc.

[0070] The horizontal frame (120) is spaced apart from the base (110) at a specific distance above. The driving unit (150) is configured to move the horizontal frame (120) in a straight line in the forward and backward horizontal direction. Thus, the position of the wafer (1) can be adjusted between the first preform and the second preform.

[0071] Additionally, the vertical frame (130) is vertically connected upward from each end of the horizontal frame (120). A hinge joint (131) is provided on the upper inner side of the vertical frame (130). Thus, the chuck support (30) is hinge-connected between a pair of vertical frames (130) through the connecting end (32).

[0072] And the first rotation means (140) is driven to rotate the chuck support (30) based on the hinge. In addition, the first angle measuring unit and the drive control unit can be included to control the chuck support (30) so that the angle can be changed to 90 degrees.

[0073] Accordingly, according to an embodiment of the present invention, a chuck support (30) installed on a motion stage (100) is positioned in a horizontal direction before the wafer (1) is installed, and in this state, the wafer (1) is installed on the chuck of the chuck support (30), and then the wafer (1) is fixed through the wafer fixing part (33). Then, when the wafer detector (34) determines that the wafer has been installed, the first rotation means (140) is driven to change the angle of the chuck support so that the planar direction of the wafer (1) becomes a vertical direction.

[0074] Then, the drive unit (150) is driven as needed to adjust the position of the wafer between the first preform and the second preform.

[0075] At the same time, one side of the wafer (1) is measured through the first preform, and the other side of the wafer (1) is measured by the second preform.

[0076]

[0077] FIG. 12 illustrates a schematic diagram of a freeform surface 3D shape measurement system using a vertical deflection measurement method that eliminates gravity error according to a second embodiment of the present invention. FIG. 13a to 13f also illustrate a perspective view, side view, front view, rear view, and top view of a motion stage according to an embodiment of the present invention.

[0078] In the second embodiment of the present invention, the apparatus comprises a chuck support on which a wafer is mounted, and a motion stage that changes the angle of the chuck support and rotates the chuck support around a vertical axis.

[0079] It also includes a preform for measuring the shape of the wafer when the planar direction of the wafer is parallel to the vertical direction.

[0080] That is, in the second embodiment of the present invention, a motion stage further comprising a second rotation means is configured to continuously measure one side and the other side of a wafer through a single preform.

[0081] A wafer (1) is mounted on a chuck support (30) with the planar direction of the wafer (1) in a horizontal direction, and the chuck support (30) is rotated by the first rotation means (140) of the motion stage (100) to change the angle so that the planar direction of the wafer becomes parallel to the vertical direction during measurement mode. Then, one side of the wafer (1) is measured through a preform, and after rotating the chuck support 180 degrees around the vertical axis by the second rotation means (170), the other side of the wafer (1) is measured through a preform.

[0082] A preform according to the second embodiment of the present invention may be configured to include a pattern generating unit (10) that generates a pattern and projects it onto a wafer (1), and a detector (20) that acquires image data of a deformed pattern reflected from the wafer (1).

[0083] As previously mentioned, the chuck support according to the second embodiment of the present invention may be configured to include a mounting hole, which is a space where a wafer (1) is installed, a plurality of chucks (31), a wafer fixing part (33) that fixes the wafer (1) after mounting the wafer on the chucks (31), and a connecting end (32) whose two ends are hinge-connected to each frame of the motion stage (100).

[0084] In addition, the motion stage (100) according to the second embodiment of the present invention is configured to include a stage (160) positioned on a base (110) at a specific interval apart from each other, a horizontal frame (120) positioned on the stage (160), and a vertical frame (130) vertically connected upward from each end of the horizontal frame (120), as shown in FIGS. 13a to 13e.

[0085] And the chuck support (30) is hinged between a pair of vertical frames (130) through a connecting end (32). Accordingly, the first rotation means (140) is driven to rotate the chuck support (30) with respect to the hinge.

[0086] In addition, in the second embodiment, a second rotation means (170) is provided between the stage (160) and the horizontal frame (120) to drive the frame around a vertical axis. The motion stage (100) includes a drive unit (150) that moves the stage (160) linearly in the forward and backward horizontal directions.

[0087] Accordingly, in mounting mode, the wafer (1) is mounted on the chuck support (30) with the planar direction of the wafer (1) being horizontal, and the chuck support (30) is rotated 90 degrees by the first rotation means (140) of the motion stage (100) to change the angle so that the planar direction of the wafer becomes parallel to the vertical direction in measurement mode. Then, one side of the wafer (1) is measured through the preform, and after rotating the chuck support (30) 180 degrees around the vertical axis by the second rotation means (170), the other side of the wafer (1) is measured through the preform.

[0088]

[0089] FIG. 14 illustrates a schematic diagram of a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error removed according to the third embodiment of the present invention. In the third embodiment of the present invention, the object to be measured corresponds to a Si mold wafer.

[0090] Since the mold surface cannot be measured by the previously mentioned pattern generating unit (10) and detector (20), in the third embodiment, a moiré measuring unit (40) is provided to measure the mold surface.

[0091] The configuration of the chuck support (30) and the motion stage (100) according to the third embodiment is the same as the configuration of the first embodiment mentioned above.

[0092] In the third embodiment, the first preform is composed of a pattern generating unit (11) and a detector (21), and the second preform is composed of a moiré measuring unit (40). The moiré measuring unit (40) is composed of a moiré pattern generating unit (41) that generates a moiré pattern and projects it onto a measurement target, and a moiré detector (42) that acquires image data of a deformed moiré pattern reflected from the measurement target.

[0093] Accordingly, according to an embodiment of the present invention, a chuck support (30) installed on a motion stage (100) is positioned in a horizontal direction before the wafer (1) is installed, and in this state, the wafer (1) is installed on the chuck of the chuck support (30), and then the wafer (1) is fixed through the wafer fixing part (33). Then, when the wafer detector (34) determines that the wafer has been installed, the first rotation means (140) is driven to change the angle of the chuck support so that the planar direction of the wafer (1) becomes a vertical direction.

[0094] Then, the drive unit (150) is driven as needed to adjust the position of the wafer between the first preform and the second preform.

[0095] At the same time, the Si surface of the wafer (1) is measured through the preform, and the moiré measuring unit (40) measures the mold surface.

[0096]

[0097] In addition, the apparatus and method described above are not limited to the configurations and methods of the embodiments described above; rather, all or part of each embodiment may be selectively combined to allow for various modifications to be made.

Claims

1. A freeform 3D shape measurement system using a vertical deflection measurement method that eliminates gravity error, Chuck support on which a wafer is mounted; A motion stage for changing the angle of the above-mentioned chuck support; A first preform for measuring the shape of one side of the wafer when the planar direction of the wafer is parallel to the vertical direction; and A second preform for measuring the shape of the other side of the wafer when the planar direction of the wafer is parallel to the vertical direction; A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized in that a wafer is mounted on a chuck support in a state where the planar direction of the wafer is horizontal, and the chuck support is rotated by a first rotation means of the motion stage to change the angle so that the planar direction of the wafer becomes parallel to the vertical direction during measurement mode.

2. In Paragraph 1, Each of the above-mentioned first preform and the above-mentioned second preform is, A pattern generating unit that generates a pattern and projects it onto a measurement target; and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized by including a detector that acquires image data of a deformed pattern reflected from the object to be measured.

3. As a freeform surface 3D shape measurement system using a vertical deflection measurement method with gravity error eliminated, Chuck support on which a wafer is mounted; A motion stage that changes the angle of the chuck support and rotates the chuck support around a vertical axis; A preform for measuring the shape of the wafer in a state where the planar direction of the wafer is parallel to the vertical direction; and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized in that a wafer is mounted on a chuck support with the planar direction of the wafer being horizontal, the chuck support is rotated by a first rotation means of the motion stage to change the angle so that the planar direction of the wafer becomes parallel to the vertical direction during measurement mode to measure one side of the wafer through the preform, and after rotating the chuck support 180 degrees with respect to the vertical axis by a second rotation means, the other side of the wafer is measured through the preform.

4. In Paragraph 3, The above preform is, A pattern generating unit that generates a pattern and projects it onto a measurement target; and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized by including a detector that acquires image data of a deformed pattern reflected from the object to be measured.

5. In Paragraph 1 or 3, A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized in that the chuck support comprises a mounting hole, which is a space for installing a wafer, a plurality of chucks, a wafer fixing part that fixes the wafer after mounting the wafer on the chuck, and a connecting end, the ends of which are hinge-connected to each of the frames of the motion stage.

6. In Paragraph 5, The above motion stage is, It includes a base, a horizontal frame disposed on the base, and a vertical frame vertically connected upward from each of the two ends of the horizontal frame. The above chuck support is hinge-connected between a pair of vertical frames through a connecting end, and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized in that the first rotation means is driven to rotate the chuck support based on a hinge.

7. In Paragraph 6, The above motion stage is, A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized by including a driving unit that moves the above horizontal frame in a straight line in the forward and backward horizontal directions.

8. In Paragraph 5, The above motion stage is, It includes a base, a stage disposed on the base, a horizontal frame, a vertical frame vertically connected upward from each end of the horizontal frame, and a second rotation means provided between the stage and the horizontal frame to rotate the chuck support with respect to a vertical axis. The above chuck support is hinge-connected between a pair of vertical frames through a connecting end, and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized in that the first rotation means is driven to rotate the chuck support based on a hinge.

9. In Paragraph 8, The above motion stage is, A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized by including a driving unit that moves the above stage in a straight line in the forward and backward horizontal directions.

10. In Paragraph 1, At least one of the first preform and the second preform is composed of a moiré measuring part, and The above moiré measuring unit includes a moiré pattern generating unit that generates a moiré pattern and projects it onto a measurement target; and A three-dimensional shape measurement system using a deflection measurement method that eliminates gravity error, characterized by including a moiré detector that acquires image data of a deformed moiré pattern reflected from the object to be measured.

Images