Contour shape measuring apparatus and method

Abstract

To provide a method and a device for measuring an outline shape for measuring the shape of an outline more accurately.SOLUTION: The present invention relates to an outline shape measuring device for measuring the shape of the outline of a disc-like measurement target with a bevel-processed peripheral part. The outline shape measuring device measures the shape of the outline as a shadow outline shape on the basis of a shadow image obtained by taking an image of the shadow of the peripheral part created by applying light to the peripheral part, from the direction of the tangent line of the outer periphery of the peripheral part, measures the outline shape of the peripheral part as the shape of the optical outline by measuring the distance to the measurement target by using light from a plane direction, and determines the shape of the outline on the basis of the shape of the shadow outline measured by the shadow outline shape measurement unit and the optical outline shape measured by the optical outline shape measurement unit.SELECTED DRAWING: Figure 1

Description

Technical Field

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[0001] The present invention relates to a contour shape measuring apparatus and a contour shape measuring method for measuring a contour shape of a disk-shaped measurement object having a bevelled peripheral portion.

Background Art

[0002] An apparatus for measuring a contour shape of a disk-shaped measurement object is disclosed, for example, in Patent Document 1. The shape measuring apparatus disclosed in this Patent Document 1 includes a light projecting means for projecting light from a direction parallel to each of the front and back surfaces of the measurement object onto a measurement portion including a chamfered end portion in the disk-shaped measurement object, and an imaging means for imaging the measurement portion from a direction opposite to the light projecting direction, and is a shape measuring apparatus for measuring the contour shape of the measurement portion by performing image processing on the projection image of the measurement portion obtained by the imaging means, and includes a thickness measuring means for measuring the thickness of a reference position in the measurement portion of the measurement object, an image processing means for deriving first contour shape information of the measurement portion by performing image processing on the projection image of the measurement portion, and a contour shape correcting means for correcting the first contour shape information by correcting a thickness distribution specified from the first contour shape information based on the thickness measured by the thickness measuring means and the dimension of the measurement portion in the light projecting direction of the measurement portion, and outputting corrected second contour shape information.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] > Incidentally, when thinning a wafer with an R-chamfered outer edge, edge pitting can occur due to the R-shape of the R-chamfer, which can cause the wafer to crack. To prevent this wafer cracking, trimming (edge ​​trimming) is sometimes performed to create a step in the height direction by grinding away the R-shape with a polishing blade. When attempting to measure the contour shape of such a trimmed wafer based on the shadow of the wafer created by shining light on the wafer, as in the shape measuring device disclosed in Patent Document 1, the shape of the step may become blurred due to light scattering at the step, reducing the measurement accuracy.

[0005] This invention was made in view of the above circumstances, and its purpose is to provide a contour shape measuring device and a contour shape measuring method that can measure contour shapes with greater accuracy. [Means for solving the problem]

[0006] As a result of various studies, the inventors have found that the above objective can be achieved by the present invention as described below. That is, a contour shape measuring device according to one aspect of the present invention is a device for measuring the contour shape of a disc-shaped object to be measured, the device comprising: a shadow contour shape measuring unit that measures the contour shape as a shadow contour shape based on a shadow image captured by shining light on the peripheral edge from the tangential direction of the outer circumference; an optical contour shape measuring unit that measures the contour shape of the peripheral edge as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction; and a contour shape calculation unit that determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the optical contour shape measured by the optical contour shape measuring unit.

[0007] Such a contour shape measuring device includes a light contour shape measuring unit in addition to a shadow contour shape measuring unit. Since the contour shape is determined based on the shadow contour shape measured by the shadow contour shape measuring unit and the light contour shape measured by the light contour shape measuring unit, the contour shape can be measured with greater accuracy.

[0008] In another embodiment, in the contour shape measuring device described above, the optical contour shape measuring unit is an optical section contour shape measuring unit that measures the optical contour shape as an optical section contour shape by an optical section method from the surface direction.

[0009] According to this, a contour shape measuring device can be provided that measures the optical contour shape as an optical section contour shape using the optical section method.

[0010] In another embodiment, in the contour shape measuring device described above, the optical contour shape measuring unit is a confocal contour shape measuring unit that measures the optical contour shape as a confocal contour shape by the confocal method.

[0011] According to this, a contour shape measuring device can be provided that measures the optical contour shape as a confocal contour shape from the aforementioned surface direction using the confocal method.

[0012] In another embodiment, the contour shape measuring device described above includes an optical contour shape measuring unit that measures the contour shape of the peripheral portion as an optical section contour shape from the direction of the surface of one of the surfaces of the object to be measured, one surface and the other surface facing the one surface, using an optical section method, and a confocal contour shape measuring unit that measures the contour shape of the peripheral portion as a confocal contour shape from the direction of the surface of the other surface using a confocal method, wherein the contour shape calculation unit determines the contour shape on the one surface based on the shadow contour shape measured by the shadow contour shape measuring unit and the optical section contour shape measured by the optical contour shape measuring unit, and determines the contour shape on the other surface based on the shadow contour shape measured by the shadow contour shape measuring unit and the confocal contour shape measured by the confocal contour shape measuring unit.

[0013] Such a contour shape measuring device has a light section contour shape measuring unit on one side and a confocal contour shape measuring unit on the other side, allowing for more accurate measurement of the contour shape on both sides of the peripheral area.

[0014] In another embodiment, the contour shape measuring device described above further includes a noise reduction processing unit that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape, and the contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the noise-reduced contour shape obtained by the noise reduction processing unit from the optical contour shape measured by the optical contour shape measuring unit. Preferably, in the contour shape measuring device described above, the optical contour shape measuring unit is an optical section contour shape measuring unit that measures the optical contour shape as an optical section contour shape by optical section method from the surface direction, the noise reduction processing unit removes noise generated in the height direction from the optical section contour shape measured by the optical section contour shape measuring unit to obtain a noise-reduced contour shape, and the contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the noise-reduced contour shape obtained by the noise reduction processing unit from the optical section contour shape measured by the optical section contour shape measuring unit. Preferably, in the contour shape measuring apparatus described above, the optical contour shape measuring unit is a confocal contour shape measuring unit that measures the optical contour shape as a confocal contour shape by the confocal method, the noise reduction processing unit removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measuring unit to obtain a noise-reduced contour shape, and the contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the noise-reduced contour shape obtained by the noise reduction processing unit from the confocal contour shape measured by the confocal contour shape measuring unit.Preferably, in the contour shape measuring device described above, the optical contour shape measuring unit comprises an optical section contour shape measuring unit that measures the contour shape of the peripheral portion as an optical section contour shape from the direction of the surface of one of the two surfaces of the object to be measured, one surface and the other surface facing the one surface, using the optical section method, and a confocal contour shape measuring unit that measures the contour shape of the peripheral portion as a confocal contour shape from the direction of the surface of the other surface using the confocal method, and the noise reduction processing unit removes noise generated in the height direction from the optical section contour shape measured by the optical section contour shape measuring unit. The first noise-removed contour shape is determined by the confocal contour shape measurement unit, and the second noise-removed contour shape is determined by removing noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement unit. The contour shape calculation unit then determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit, the first noise-removed contour shape obtained by the noise removal processing unit from the light section contour shape measured by the light section contour shape measurement unit, and the second noise-removed contour shape obtained by the noise removal processing unit from the confocal contour shape measured by the confocal contour shape measurement unit.

[0015] Such contour shape measuring devices determine the contour shape based on a noise-removed contour shape, allowing for more accurate contour shape measurement.

[0016] In another embodiment, in the contour shape measuring device described above, the noise reduction processing unit removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measuring unit.

[0017] In trimming processes, grinding blades are used to remove material, which can result in uncut areas or shavings (debris), creating noise in the contour shape. Since the amount of uncut material and shavings varies from one object to another, using a predetermined threshold value to determine whether or not something is noise may not accurately identify the noise. The above contour shape measuring device uses a threshold value that corresponds to the variation in height, allowing for more appropriate noise removal and, consequently, more accurate measurement of the contour shape.

[0018] Another aspect of the present invention relates to a contour shape measurement method for measuring the contour shape of a disc-shaped object to be measured, the method comprising: a shadow contour shape measurement step of measuring the contour shape as a shadow contour shape based on a shadow image captured of the shadow of the peripheral portion generated by shining light on the peripheral portion from the tangential direction of the outer circumference; an optical contour shape measurement step of measuring the contour shape of the peripheral portion as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction; and a contour shape calculation step of determining the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the optical contour shape measured by the optical contour shape measurement step.

[0019] This contour shape measurement method includes a light contour shape measurement step in addition to a shadow contour shape measurement step, and determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the light contour shape measured by the light contour shape measurement step, thereby enabling more accurate measurement of the contour shape.

[0020] In another embodiment, in the above-described contour shape measurement method, the optical contour shape measurement step is an optical section contour shape measurement step in which the optical contour shape is measured as an optical section contour shape by an optical section method from the surface direction.

[0021] According to this, a contour shape measurement method can be provided that measures the optical contour shape as an optical section contour shape using the optical section method.

[0022] In another embodiment, in the above-described contour shape measurement method, the optical contour shape measurement step is a confocal contour shape measurement step in which the optical contour shape is measured as a confocal contour shape from the surface direction by the confocal method.

[0023] According to this, a contour shape measurement method can be provided that measures the optical contour shape as a confocal contour shape using the confocal method.

[0024] In another aspect, in these above-described contour shape measurement methods, the optical contour shape measurement step includes an optical cutting contour shape measurement step of measuring the contour shape of the peripheral portion as an optical cutting contour shape from the surface direction of one surface of the measurement object and one of the other surfaces facing the one surface by the optical cutting method, and a confocal contour shape measurement step of measuring the contour shape of the peripheral portion as a confocal contour shape from the surface direction of the other surface by the confocal method. The contour shape calculation step obtains the contour shape on the one surface based on the shadow contour shape measured by the shadow contour shape measurement step and the optical cutting contour shape measured by the optical cutting contour shape measurement step, and obtains the contour shape on the other surface based on the shadow contour shape measured by the shadow contour shape measurement step and the confocal contour shape measured by the confocal contour shape measurement step.

[0025] Such a contour shape measurement method includes an optical cutting contour shape measurement step for measuring one surface and a confocal contour shape measurement step for measuring the other surface, so that the contour shapes of both surfaces at the peripheral portion can be measured more accurately.

[0026] In another embodiment, the above-described contour shape measurement method further comprises a noise reduction processing step to obtain a noise-reduced contour shape by removing noise generated in the height direction from the optical contour shape measured by the optical contour shape measurement step, wherein the contour shape calculation step determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the noise-reduced contour shape obtained in the noise reduction processing step from the optical contour shape measured by the optical contour shape measurement step. Preferably, in the above-described contour shape measurement method, the optical contour shape measurement step is an optical section contour shape measurement step that measures the optical contour shape as an optical section contour shape by optical section method from the surface direction, the noise reduction processing step obtains a noise-reduced contour shape by removing noise generated in the height direction from the optical section contour shape measured by the optical section contour shape measurement step, and the contour shape calculation step determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the noise-reduced contour shape obtained in the noise reduction processing step from the optical section contour shape measured by the optical section contour shape measurement step. Preferably, in the contour shape measurement method described above, the optical contour shape measurement step is a confocal contour shape measurement step in which the optical contour shape is measured as a confocal contour shape by the confocal method, the noise reduction processing step removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement step to obtain a noise-reduced contour shape, and the contour shape calculation step determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the noise-reduced contour shape obtained in the noise reduction processing step from the confocal contour shape measured by the confocal contour shape measurement step.Preferably, in the above-described contour shape measurement method, the optical contour shape measurement step includes an optical cutting contour shape measurement step of measuring the contour shape of the peripheral portion as an optical cutting contour shape from the surface direction of one surface of the measurement object and one of the other surfaces facing the one surface by the optical cutting method, and a confocal contour shape measurement step of measuring the contour shape of the peripheral portion as a confocal contour shape from the surface direction of the other surface by the confocal method. The noise removal processing step removes noise generated in the height direction from the optical cutting contour shape measured by the optical cutting contour shape measurement step to obtain a first noise-removed contour shape, and removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement step to obtain a second noise-removed contour shape. The contour shape calculation step obtains the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step, the first noise-removed contour shape obtained in the noise removal processing step from the optical cutting contour shape measured by the optical cutting contour shape measurement step, and the second noise-removed contour shape obtained in the noise removal processing step from the confocal contour shape measured by the confocal contour shape measurement step.

[0027] Such a contour shape measurement method can measure the contour shape with higher accuracy because it obtains the contour shape based on the noise-removed contour shape from which noise has been removed.

[0028] In another aspect, in the above-described contour shape measurement method, the noise removal processing step removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measurement step.

[0029] Such a contour shape measurement method can remove noise more appropriately because it uses a threshold value corresponding to the height variation, and thus can measure the contour shape with higher accuracy.

Advantages of the Invention

[0030] The contour shape measurement apparatus and the contour shape measurement method according to the present invention can measure the contour shape with higher accuracy.

Brief Description of the Drawings

[0031] [Figure 1] This is a block diagram showing the configuration of the contour shape measuring device in the first embodiment. [Figure 2] This is a schematic diagram illustrating the measurement system in the contour shape measuring device of the first embodiment. [Figure 3] This is a schematic diagram illustrating the stage in the contour shape measuring device of the embodiment. [Figure 4] This is a diagram illustrating the shape of the object being measured after trimming. [Figure 5] This is a diagram to explain the cause of the noise. [Figure 6] This diagram illustrates the superposition of the shadow contour shape and the light section contour shape. [Figure 7] This is a flowchart showing the operation of the contour shape measuring device in the first embodiment. [Figure 8] This is a block diagram showing the configuration of the contour shape measuring device in the second embodiment. [Figure 9] This is a schematic diagram illustrating the measurement system in the contour shape measuring device of the second embodiment. [Figure 10] This is a flowchart showing the operation of the contour shape measuring device in the second embodiment. [Figure 11] This is a block diagram showing the configuration of the contour shape measuring device in the third embodiment. [Figure 12] This is a schematic diagram illustrating the measurement system in the contour shape measuring device of the third embodiment. [Figure 13] This is a flowchart showing the operation of the contour shape measuring device in the third embodiment. [Modes for carrying out the invention]

[0032] Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments. In each figure, components denoted by the same reference numerals are identified as identical components, and their descriptions are omitted where appropriate. In this specification, general reference numerals are used without subscripts, while individual components are indicated by subscripts.

[0033] The contour shape measuring device in this embodiment is a device for measuring the contour shape of a disc-shaped object to be measured, whose peripheral edge has been beveled. This contour shape measuring device comprises a shadow contour shape measuring unit, an optical contour shape measuring unit, and a contour shape calculation unit. The shadow contour shape measuring unit measures the contour shape as a shadow contour shape based on a shadow image captured by shining light on the peripheral edge from the tangential direction of the outer circumference. The optical contour shape measuring unit measures the contour shape of the peripheral edge as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction. The contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the optical contour shape measured by the optical contour shape measuring unit. Hereinafter, such a contour shape measuring device and the contour shape measuring method implemented therein will be described in more detail with reference to the first to third embodiments.

[0034] (First Embodiment) In the contour shape measuring device of the first embodiment, the optical contour shape measuring unit is used, which measures the optical contour shape as an optical section contour shape by optical section method from the surface direction. That is, the contour shape measuring device of the first embodiment comprises a shadow contour shape measuring unit similar to the one described above, an optical section contour shape measuring unit, and a contour shape calculation unit. The optical section contour shape measuring unit measures the contour shape of the peripheral portion as an optical section contour shape by optical section method from the surface direction. The contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the optical section contour shape measured by the optical section contour shape measuring unit. A more detailed explanation follows.

[0035] Figure 1 is a block diagram showing the configuration of the contour shape measuring device in the first embodiment. Figure 2 is a schematic diagram illustrating the measurement system in the contour shape measuring device of the first embodiment. Figure 3 is a schematic diagram illustrating the stage in the contour shape measuring device of the embodiment. Note that Figure 3 schematically shows the stage in the contour shape measuring device of the first to third embodiments. Figure 4 is a diagram illustrating the shape of the trimmed object to be measured. Figure 5 is a diagram illustrating the cause of noise. Figure 5A is a schematic cross-sectional view showing the peripheral edge of an example of an object to be measured, a WA, and Figure 5B is a schematic plan view of the WA to be measured, showing its height (thickness) in grayscale. Note that in Figure 5B, although the WA to be measured is disc-shaped, the circumferential direction is converted to a straight line to illustrate the WA to be measured. Figure 6 is a diagram illustrating the superposition of the shadow contour shape and the light section contour shape. Figure 6A shows the shape before superposition, and Figure 6B shows the shape after superposition.

[0036] The contour shape measuring device 1000A in the first embodiment includes, for example, a shadow contour shape measuring unit 1, a light section contour shape measuring unit 2, a stage 3, a control processing unit 4A, an input unit 5, an output unit 6, an interface unit (IF unit) 7, and a storage unit 8A, as shown in Figures 1 to 3.

[0037] Stage 3 is a device on which the WA to be measured is placed and supported, connected to the control processing unit 4A, and rotates the WA to be measured in the circumferential direction θ according to the control processing unit 4A, and moves the WA to be measured within a predetermined range of movement in a horizontal direction perpendicular to the height direction (thickness direction). In this embodiment, as shown in Figure 3, for example, Stage 3 comprises a cylindrical rotating support member 31 on which the WA to be measured is placed and supported, which serves as the axis of rotation, a drive unit 32 that rotates the rotating support member 31 and moves linearly in the horizontal direction within the predetermined range of movement, and a base 33 that supports the rotating support member 31 and the drive unit 32. One end face of the rotating support member 31 is a horizontal plane on which the WA to be measured is placed, and for example, the rotating support member 31 has a through-opening along its central axis that is connected to a suction pump (not shown), and the WA to be measured is pulled through the through-opening by the negative pressure of the suction pump and fixed to the one end face. The drive unit 32 is rotatably connected to the rotating support member 31 at its other end and is configured to include a drive mechanism such as an actuator, such as a servo motor, or a reduction gear, for rotationally driving the rotating support member 31. The drive unit 32 is configured to move linearly relative to the base 33, for example, by rack and pinion, and the base 33 is configured to include a rack, and the drive unit 32 further includes a pinion for linear movement on the rack and an actuator, such as a servo motor, for rotating the pinion. In this stage 3, the object to be measured WA, which is placed and fixed on one end face of the rotating support member 31, rotates in the circumferential direction θ as the rotating support member 31 rotates due to the drive unit 32, and moves linearly in the horizontal direction as it moves on the base 33 due to the drive unit.

[0038] The WA to be measured can be any disc-shaped material with a beveled edge, such as a wafer used in semiconductor manufacturing (e.g., a silicon wafer) or an aluminum or glass magnetic disk substrate used in a hard disk. The beveling is, for example, a trimming process (edge ​​trimming) that creates one or more steps in the radial direction X in the height direction. In this trimming process, for example, a step in the height direction is formed by grinding the surface of the peripheral edge of the WA to be measured to be approximately flat using a polishing blade, as shown in Figure 4. In the example shown in Figure 4, one trim (frame) TR is formed. There is an approximately vertical step between the original wafer surface SF and this trim TR, forming a stepped shape.

[0039] The shadow contour shape measuring unit 1 is a device that measures the contour shape of a WA to be measured as a shadow contour shape based on a shadow image captured from the shadow of the peripheral edge of the WA to be measured, which is created by shining light on the peripheral edge of the WA to be measured from the tangential direction of the outer circumference. The shadow contour shape measuring unit 1 rotates the WA to be measured sequentially at predetermined angular intervals (sampling intervals) using the stage 3, and measures each shadow contour shape (each outer contour shape of the cross section along each radial direction of each measurement point) as seen from the side at each measurement point (sampling point) in the circumferential direction. The shadow contour shape measuring unit 1 comprises, for example, a first measurement unit 11 and a first shape calculation unit 12 (42).

[0040] The first measuring unit 11 is connected to the control processing unit 4A and, in accordance with the control of the control processing unit 4A, generates a shadow of the peripheral area of ​​the WA to be measured by shining light from the tangential direction of the outer circumference, and is a device that images the generated shadow of the peripheral area. Such a first measuring unit 11 includes, for example, an illumination unit 111, an illumination optical system 112, a light receiving optical system 113, and an imaging unit 114, as shown in Figure 2. The illumination unit 111 is connected to the control processing unit 4A and emits illumination light in accordance with the control of the control processing unit 4A, and is configured with a light source such as a white light-emitting diode. The illumination optical system 112 collimates the illumination light emitted (irradiated) from the illumination unit 111 into parallel light, and is configured with, for example, one or more lenses. The light-receiving optical system 113 forms an optical image of the shadow of the peripheral area of ​​the WA to be measured, which is generated by illuminating the peripheral area with the parallel light, onto the imaging surface (light-receiving surface) of the imaging unit 114, and is configured with, for example, one or more lenses. The imaging unit 114 is connected to the control processing unit 4A and, according to the control of the control processing unit 4A, converts the optical image of the peripheral area shadow formed on the imaging surface into an electrical signal, and is configured with, for example, a CCD type area image sensor or a CMOS type area image sensor. The imaging unit 114 outputs the data (shadow data) obtained by this imaging to the control processing unit 4A. The illumination unit 111, illumination optical system 112, light-receiving optical system 113, and imaging unit 114 are arranged in this order such that their respective optical axes coincide with each other.

[0041] The first shape calculation unit 12(42) is functionally configured in the control processing unit 4A as described later in this embodiment, and generates shadow image data, which is data representing the shadow image of the peripheral part (shadow image), by image processing (first image processing) of the output of the imaging unit 114 (the shadow data), and generates the contour shape of the measurement target WA as the shadow contour shape by image processing (second image processing) of the generated shadow image data. The second image processing includes, for example, a 21st image processing that extracts edges using an edge filter such as a Sobel filter, a 22nd image processing that removes noise from the edges extracted in the 21st image processing using a preset brightness threshold, and a 23rd image processing that determines a curve to fit the edges after noise removal by the 22nd image processing as the shadow contour shape on a subpixel basis.

[0042] The light section contour shape measuring unit 2 is a device that measures the contour shape of the peripheral part of the WA to be measured as a light section contour shape by the light section method from the surface direction. The light section contour shape measuring unit 2 rotates the WA to be measured sequentially at predetermined angular intervals (the sampling interval) using the stage 3, and measures each light section contour shape (each outer contour shape of the cross section along each radial direction of each measurement location (the outer contour shape on the side irradiated by the illumination light) as seen from the side at each measurement point (the sampling point) in the circumferential direction. The light section contour shape measuring unit 2 comprises, for example, a second measurement unit 21 and a second shape calculation unit 22 (43). The second measurement unit 21 is connected to the control processing unit 4A and, according to the control of the control processing unit 4A, irradiates illumination light in a straight slit shape and receives the reflected light of the illumination light reflected by the WA to be measured. The second measurement unit 21 outputs the data obtained by this reception (light section data) to the control processing unit 4A. The second measurement unit 21 includes, for example, a light source, a slit member that forms a slit-shaped illumination light from the light source, and an image sensor that receives and captures the reflected light of the illumination light. The image sensor outputs the light section data obtained by this imaging to the control processing unit 4A. The second shape calculation unit 22 (43) is functionally configured in the control processing unit 4A as described later in this embodiment, and processes the output of the second measurement unit 21 (the light section data) according to the light section method to determine the contour shape of the peripheral part of the WA to be measured as the light section contour shape. In the light section method, the direction of reception of the reflected light (receiving angle) changes according to the distance from the second measurement unit 21 to the surface of the WA to be measured. The distance from the second measurement unit 21 to the surface of the WA to be measured is determined by using the principle of triangulation from the direction of propagation of the illumination light (irradiation angle), the direction of reception of the reflected light (receiving angle), and the distance between the irradiation position of the illumination light and the reception position of the reflected light (baseline length). By determining this distance, the contour shape (optical section contour shape) of the peripheral area of ​​the WA being measured can be determined from the surface direction.

[0043] In the first embodiment, as described above, the light section contour shape measuring unit 2 corresponds to an example of the light contour shape measuring unit that measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance from the surface direction to the object to be measured using light.

[0044] As shown in Figure 2, the first measuring unit 11 and stage 3 are arranged such that when the WA to be measured is moved by stage 3 to the shadow contour shape measurement position PS1 (the position where the WA to be measured is used to measure the shadow contour shape by the shadow contour shape measurement unit 1), the peripheral edge of the WA to be measured is positioned between the illumination optical system 112 and the light-receiving optical system 113 in the first measuring unit 11, and the tangential direction of the outer circumference of the WA to be measured coincides with or is parallel to the optical axis of the first measuring unit 11. The shadow contour shape measurement position PS1 is the position of the WA to be measured when the shadow contour shape is measured by the shadow contour shape measurement unit 1. As shown in Figure 2, the second measuring unit 21 and stage 3 are arranged such that when the WA to be measured is moved by stage 3 to the light section contour shape measurement position PS2, the extension direction of the slit-shaped illumination light in the second measuring unit 21 (the direction in which the illumination light extends in a slit shape) coincides with the radial direction X of the WA to be measured, and the peripheral edge of the WA to be measured is illuminated by the slit-shaped illumination light in the second measuring unit 21. The measurement position PS2 of the light section contour shape is the position of the target WA when measuring the light section contour shape with the light section contour shape measuring unit 2. The first measuring unit 11 of the shadow contour shape measuring unit 1, the second measuring unit 21 of the light section contour shape measuring unit 2, and the stage 3 are arranged and fixed as described above.

[0045] Furthermore, the predetermined range of movement when moving the drive unit 32 horizontally in stage 3 is defined such that, for example, when the drive unit 32 moves to one end, the measurement target WA is located at the measurement position PS1 of the shadow contour shape, as shown in Figure 2, and when the drive unit 32 moves to the other end, the measurement target WA is located at the measurement position PS2 of the light section contour shape.

[0046] The input unit 5 is connected to the control processing unit 4A and is a device that inputs various commands, such as a command to instruct the start of measurement, and various data necessary for operating the contour shape measuring device 1000A, such as the name of the object to be measured. Examples of input units include a keyboard, mouse, and multiple input switches assigned to predetermined functions. The output unit 6 is connected to the control processing unit 4A and is a device that outputs commands, data, and contour shapes input from the input unit 5 according to the control of the control processing unit 4A. Examples of output units include display devices such as CRT displays, LCDs (liquid crystal displays), and organic EL displays, and printing devices such as printers.

[0047] The input unit 5 and output unit 6 may be configured as touch panels. In this configuration, the input unit 5 is a position input device that detects and inputs the operating position, such as a resistive or capacitive touchscreen, and the output unit 6 is a display device. In this touch panel, a position input device is provided on the display surface of the display device, and one or more candidate input contents that can be input to the display device are displayed. When the user touches the display position that displays the input content they want to input, the position input device detects that position, and the display content displayed at the detected position is input to the contour shape measuring device 1000A as the user's operation input. With such a touch panel, the user can easily understand the input operation intuitively, thus providing a contour shape measuring device 1000A that is easy for the user to use.

[0048] The IF unit 7 is connected to the control processing unit 4A and, in accordance with the control of the control processing unit 4A, is a circuit that inputs and outputs data to and from external devices, for example. Examples include an RS-232C serial communication interface circuit, an interface circuit using the Bluetooth® standard, and an interface circuit using the USB standard. Alternatively, the IF unit 7 may be a communication interface circuit that sends and receives communication signals to and from external devices, such as a data communication card or a communication interface circuit conforming to the IEEE 802.11 standard.

[0049] The memory unit 8A is connected to the control processing unit 4A and is a circuit that stores various predetermined programs and various predetermined data in accordance with the control of the control processing unit 4A. The various predetermined programs include, for example, a first control processing program, and the first control processing program includes, for example, a first control program, a first shape calculation program, a second shape calculation program, a noise reduction program, and a first contour shape calculation program. The first control program is a program that controls each part 1 to 3, 5 to 7, and 8A of the contour shape measuring device 1000A according to the function of each part. The first shape calculation program is a program that generates the shadow image data by performing the first image processing on the output of the imaging unit 114 and determines the shadow contour shape by performing the second image processing on the generated shadow image data. The second shape calculation program is a program that determines the light section contour shape by processing the output of the second measurement unit 21 according to the light section method. The noise reduction program is a program that removes noise generated in the height direction from the light section contour shape measured by the light section contour shape measuring program to determine the noise-reduced contour shape. The first contour shape calculation program is a program that determines the contour shape based on the shadow contour shape obtained by the shadow contour shape measurement program and the light section contour shape obtained by the second shape calculation program of the light section contour shape measurement program.

[0050] The aforementioned various predetermined data include, for example, data necessary for executing each of these programs, such as the name of the measurement target, positional relationship information, data being processed, and contour shape. The positional relationship information represents the positional relationship between the measurement position of the first measurement unit 11 in the shadow contour shape measurement unit 1 (first measurement position) and the measurement position of the second measurement unit 21 in the light section contour shape measurement unit 2 (second measurement position). Since the shadow contour shape measurement unit 1, the light section contour shape measurement unit 2, and the stage 3 are fixedly arranged as described above, the positional relationship between the first measurement position and the second measurement position can be predetermined, and from this positional relationship information, the shadow contour shape and the light section contour shape at each measurement location can be made to correspond to each other.

[0051] Such a storage unit 8A may include, for example, a non-volatile memory element such as ROM (Read Only Memory) or a rewritable non-volatile memory element such as EEPROM (Electrically Erasable Programmable Read Only Memory). Furthermore, the storage unit 8A may include a RAM (Random Access Memory) which serves as the working memory of the control processing unit 4A, storing data generated during the execution of the predetermined program. The storage unit 8A may also be configured to include a hard disk drive with a relatively large storage capacity.

[0052] The control processing unit 4A is a circuit for determining the contour shape of the WA to be measured by controlling each part 1-3, 5-7, and 8A of the contour shape measuring device 1000A according to the function of each part. The control processing unit 4A is configured, for example, with a CPU (Central Processing Unit) and its peripheral circuits. When the first control processing program is executed, the control unit 41A, the first shape calculation unit 42(12), the second shape calculation unit 43(22), the noise reduction processing unit 44A, and the contour shape calculation unit 45A are functionally configured in the control processing unit 4A.

[0053] The control unit 41A controls each of the contour shape measuring device 1000A parts 1-3, 5-7, and 8A according to the function of each part, and is in charge of the overall control of the contour shape measuring device 1000A.

[0054] As described above, the first shape calculation unit 42(12) generates shadow image data by performing the first image processing on the output (shadow data) of the imaging unit 114, and determines the shadow contour shape by performing the second image processing on the generated shadow image data. For each of the measurement locations, the shadow contour shape of that measurement location is generated.

[0055] As described above, the second shape calculation unit 43(22) determines the optical section contour shape by processing the output (optical section data) of the second measurement unit 21 according to the optical section method. For each of the measurement locations, the optical section contour shape of that measurement location is generated.

[0056] The noise reduction processing unit 44A removes noise generated in the height direction from the light section contour shape measured by the light section contour shape measurement unit 2 to obtain a noise-reduced contour shape. For each of the light section contour shapes, a noise-reduced contour shape for that light section contour shape is generated (for each of the measurement locations, a noise-reduced contour shape for that measurement location is generated). In trimming, as described above, the material is cut with a polishing blade, so as shown in Figure 5, for example, uncut DW and shavings (debris) PT may be generated, and these uncut DW and shavings (debris) PT become noise in the contour shape. The noise reduction processing unit 44A removes this noise from the light section contour shape measured by the light section contour shape measurement unit 2. More specifically, the noise reduction processing unit 44A removes the noise using a threshold value (noise judgment threshold value) corresponding to the height variation obtained based on the light section contour shape measured by the light section contour shape measurement unit 2. More specifically, the noise reduction processing unit 44A first calculates the standard deviation σ of height from the optical section contour shape corresponding to the trim TR, and sets the noise determination threshold Thn to a predetermined value m times the standard deviation σ of height (Thn = m × σ). The standard deviation σ of height corresponds to an example of the height variation. Here, if the assumed size of the dust is Dd and the depth (step length) of the trim TR is St, it is preferable to set the predetermined value m so that the noise determination threshold Thn is within the range of Dd / 5 to St / 2 (Dd / 5 ≤ Thn ≤ St / 2). More preferably, m is set so that the noise determination threshold Thn is within the range of Dd / 3 to St / 4 (Dd / 3 ≤ Thn ≤ St / 4). This range of the noise determination threshold Thn is defined from multiple samples. In one embodiment, if Dd = 10 [μm] and St = 20 [μm], then σ = 0.65, and Thn is set to 6 × σ (m = 6). The height is determined, for example, by finding a horizontal plane from the shadow contour shape where the thickness of the WA to be measured is half, using this as the height reference plane. The shadow contour shape and the light section contour shape are then superimposed in the same manner as described later, and the height is determined as the length from the reference plane to the light section contour shape. In the description later, the shadow contour shape and the noise-removed contour shape are superimposed, but here, since they are superimposed to determine the height, the shadow contour shape and the light section contour shape before noise removal are superimposed.Next, the noise reduction processing unit 44A removes noise from the optical section contour shape measured by the optical section contour shape measurement unit 2, which corresponds to the trim TR, where the noise exceeds the noise determination threshold Thn of the trim TR. Then, the noise reduction processing unit 44A interpolates the removed portions, for example, using linear interpolation, to generate a noise-reduced contour shape.

[0057] The contour shape calculation unit 45A determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the light section contour shape measured by the light section contour shape measurement unit 2. In this embodiment, a noise reduction processing unit 44A is provided, so the contour shape calculation unit 45A determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the noise reduction contour shape obtained by the noise reduction processing unit 44A from the light section contour shape measured by the light section contour shape measurement unit 2.

[0058] More specifically, the contour shape calculation unit 45A first retrieves (reads) the shadow contour shape α measured by the shadow contour shape measurement unit 1 and the light section contour shape (noise-reduced contour shape in this embodiment) β (β1, β2) measured by the light section contour shape measurement unit 2 at the same measurement location based on the positional relationship information, as shown in Figure 6A, from the storage unit 8A, and then superimposes these shadow contour shape α and light section contour shape β by performing alignment, as shown in Figure 6B. The alignment is performed, for example, as shown in Figure 6A, by detecting a step position xα from the shadow contour shape α and a step position xβ from the light section contour shape β, and then matching these step positions xα and xβ. The step position xα is scanned radially from the inside, and is first detected as a location where the height represented by the shadow contour shape α is lower than or equal to a preset judgment threshold. The step position xβ is scanned radially from the inside, and the height represented by the optical section contour shape β is detected first as the lowest point.

[0059] The contour shape calculation unit 45A then compares the amount of blur included in the measurement by the shadow contour shape measurement unit 1 with the height of the step measured by the light section contour shape measurement unit 2 within a predetermined range including the step, and selects either the shadow contour shape measured by the shadow contour shape measurement unit 1 or the light section contour shape measured by the light section contour shape measurement unit 2 to determine the contour shape based on the comparison result. The predetermined range including the step is, for example, the range from the step to a predetermined distance set in advance radially outward (for example, 1 or 2 times the height of the step).

[0060] The areas where measurement accuracy decreases in the contour shape of a beveled WA to be measured are mainly the stepped areas where light scattering occurs, for example. Therefore, in order to reduce processing time, the measurement results used when determining the contour shape are selected. Here, while the WA to be measured is disc-shaped, the shadow contour shape measuring unit 1 measures the shadow contour shape based on a shadow image captured by shining light on the peripheral edge from the tangential direction of the outer circumference. Therefore, even if the depth of field is increased, when the focus is on the tip of the WA to be measured, a shadow image with a clear shape is obtained at the tip of the WA to be measured, while the shadow image becomes blurred as it moves away radially from the tip. Therefore, a function f(x)=y representing the amount of blur y that increases monotonically according to the distance x from the tip position or the start position of beveling is determined (estimated) from multiple samples in advance, and the difference in average height before and after the step is determined as the height h of the step. The contour shape calculation unit 45A, for example, if the amount of blur y=f(xs) at the step position xs is greater than the height h of the step at the step position xs measured by the light section contour shape measurement unit 2 (y>h), uses the light section contour shape in a predetermined range including the step position xs as the contour shape in the predetermined range. If the amount of blur y=f(xs) is not greater than the height h of the step (if the amount of blur y=f(xs) is less than or equal to the height h of the step, y≦h), uses the shadow contour shape in the predetermined range as the contour shape in the predetermined range. In the range excluding the predetermined range for each step, the shadow contour shape is used as the contour shape. This determines the final contour shape.

[0061] The contour shape calculation unit 45A determines the final contour shape by performing this process for each measurement point in the circumferential direction.

[0062] In the above description, the amount of blur y was determined as a function of distance x, but it may also be a predetermined constant yc set in advance from multiple samples, and the amount of blur yc may be compared with the height h of the step. Alternatively, for example, without performing the above comparison, the optical section contour shape in a predetermined range including the step may be used as the contour shape in the predetermined range.

[0063] In the first embodiment, the noise reduction processing unit 44A corresponds to an example of a noise reduction processing unit that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape.

[0064] These control processing units 4A, input unit 5, output unit 6, IF unit 7, and storage unit 8A can be configured using, for example, a desktop or notebook computer.

[0065] Next, the operation of this embodiment will be described. Figure 7 is a flowchart showing the operation of the contour shape measuring device in the first embodiment.

[0066] When the contour shape measuring device 1000A with this configuration is powered on, it performs the initialization of each necessary part and starts operation. The control processing unit 4A is functionally configured with the control unit 41A, the first shape calculation unit 42(12), the second shape calculation unit 43(22), the noise reduction processing unit 44, and the contour shape calculation unit 45A through the execution of its first control processing program.

[0067] When the WA to be measured is set on stage 3 and measurement begins, as shown in Figure 7, first, the contour shape measuring device 1000A, via the control unit 41A of the control processing unit 4A, acquires shadow data measured by the shadow contour shape measuring unit 1 at the shadow contour shape measurement position PS1 from its first measurement unit 11 and stores it in the storage unit 8A (S1). The WA to be measured is rotated sequentially by stage 3 at predetermined angular intervals (sampling intervals), and shadow data is acquired at each measurement point (sampling point) in the circumferential direction and stored in association with each measurement point.

[0068] Next, the contour shape measuring device 1000A, controlled by the control unit 41A of the control processing unit 4A, acquires the light section data measured by the light section contour shape measuring unit 2 at the measurement position PS2 of the light section contour shape from its second measurement unit 21 and stores it in the storage unit 8A (S2). The stage 3 rotates the object to be measured WA sequentially at the predetermined angular interval (the sampling interval), and each light section data is acquired at each measurement point (the sampling point) in the circumferential direction and stored in association with each measurement point.

[0069] Next, the contour shape measuring device 1000A generates shadow image data by performing the first image processing on the output (shadow data) of the imaging unit 114 using the first shape calculation unit 42 of the control processing unit 4A. The shadow contour shape is then determined by performing a second image processing on the generated shadow image data and stored in the storage unit 8A (S3). For each of the measurement locations, each shadow contour shape is determined and stored in association with each measurement location.

[0070] Next, the contour shape measuring device 1000A uses the second shape calculation unit 43 of the control processing unit 4A to process the output (light section data) of the second measurement unit 21 according to the light section method to determine the light section contour shape, and stores it in the storage unit 8A (S4). For each of the measurement locations, each light section contour shape is determined and stored in association with each measurement location.

[0071] Next, the contour shape measuring device 1000A removes noise from the optical section contour shape using the noise removal processing unit 44A of the control processing unit 4A, obtains a noise-removed contour shape, and stores it in the storage unit 8A (S5). A noise-removed contour shape is obtained for each of the measurement locations and stored in association with each measurement location.

[0072] Next, the contour shape measuring device 1000A determines the final contour shape using the contour shape calculation unit 45A of the control processing unit 4A and stores it in the storage unit 8A (S6). For each of the measurement points, the final contour shape is determined and stored in association with each measurement point.

[0073] Then, the contour shape measuring device 1000A outputs the contour shape of each measurement point to the output unit 6 via the control unit 41A of the control processing unit 4A (S7), and the process ends. If necessary, each contour shape may be output to an external device via the IF unit 7.

[0074] As described above, the contour shape measuring device 1000A and the contour shape measuring method implemented therein in the first embodiment measure the shadow contour shape as well as the light contour shape, and in the first embodiment, the light section contour shape. The contour shape is determined based on the shadow contour shape obtained by measuring the shadow contour shape and the light section contour shape obtained by measuring the light section contour shape, so the contour shape can be measured with greater accuracy.

[0075] The above-described contour shape measuring device 1000A and contour shape measuring method determine the contour shape based on the noise-removed contour shape, thus enabling more accurate measurement of the contour shape.

[0076] In trimming, the material is removed using a grinding blade, which can result in uncut material and debris (dust), creating noise in the contour shape. Since the amount of uncut material and debris varies from one object to another, using a predetermined threshold value to determine whether or not something is noise may not accurately identify the noise. The contour shape measuring device 1000A and contour shape measuring method use a noise determination threshold Thn that corresponds to the variation in height, allowing for more appropriate noise removal and thus more accurate measurement of the contour shape. Since the noise determination threshold Thn is determined for each trim TR, the contour shape measuring device 1000A and contour shape measuring method can more appropriately remove noise and thus more accurately measure the contour shape.

[0077] The above-described contour shape measuring device 1000A and contour shape measuring method use a noise determination threshold Thn corresponding to the variation in height, so noise can be removed more effectively, and therefore the contour shape can be measured with greater accuracy.

[0078] Next, another embodiment will be described. (Second Embodiment) In the first embodiment, an optical section contour shape measuring unit 2 was used as the optical contour shape measuring unit, but in the second embodiment, a confocal contour shape measuring unit 9 is used as the optical contour shape measuring unit. That is, the contour shape measuring device in the second embodiment comprises a shadow contour shape measuring unit similar to the one described above, a confocal contour shape measuring unit, and a contour shape calculation unit. The confocal contour shape measuring unit measures the contour shape of the peripheral portion as a confocal contour shape from the surface direction using the confocal method. The contour shape calculation unit in the second embodiment determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the confocal contour shape measured by the confocal contour shape measuring unit. A more detailed explanation follows below.

[0079] Figure 8 is a block diagram showing the configuration of the contour shape measuring device in the second embodiment. Figure 9 is a schematic diagram illustrating the measurement system in the contour shape measuring device of the second embodiment.

[0080] The contour shape measuring device 1000B in the second embodiment includes, for example, a shadow contour shape measuring unit 1, a confocal contour shape measuring unit 9, a stage 3, a control processing unit 4B, an input unit 5, an output unit 6, an interface unit (IF unit) 7, and a storage unit 8B, as shown in Figures 8 and 9. The shadow contour shape measuring unit 1, stage 3, input unit 5, output unit 6, and IF unit 7 in the contour shape measuring device 1000B of the second embodiment are the same as the shadow contour shape measuring unit 1, stage 3, input unit 5, output unit 6, and IF unit 7 in the contour shape measuring device 1000A of the first embodiment, so their description is omitted.

[0081] The confocal contour shape measuring unit 9 is a device that measures the contour shape of the peripheral portion of the WA to be measured as a confocal contour shape from the surface direction using the confocal method. The confocal contour shape measuring unit 9 rotates the WA to be measured sequentially at predetermined angular intervals (the sampling interval) using the stage 3, and measures each confocal contour shape (each outer contour shape of the cross section along each radial direction of each measurement location (the outer contour shape on the side irradiated by the illumination light) as seen from the side at each measurement point (the sampling point) in the circumferential direction. The confocal contour shape measuring unit 9 comprises, for example, a third measurement unit 91 and a third shape calculation unit 92(46). The third measurement unit 91 is connected to the control processing unit 4B and, according to the control of the control processing unit 4B, focuses and irradiates illumination light at a single point and receives the reflected light of the illumination light reflected by the WA to be measured, and is configured to be movable along the height direction (thickness direction) of the WA to be measured. For example, the third measuring unit 91 includes a confocal measuring unit that focuses illumination light at a single point and receives the reflected light of the illumination light reflected by the WA to be measured; a rod-shaped support member erected along the height direction of the WA to be measured and equipped with, for example, a rack; and a scanning drive unit equipped with a pinion and an actuator such as a servo motor for rotating the pinion, which supports the confocal measuring unit so that it can move along the support member by rack and pinion. The scanning drive unit is connected to and controlled by the control processing unit 4B. The confocal method uses the confocal principle, which states that the amount of reflected light is maximum when the light is in focus, to determine the distance to the WA to be measured. More specifically, the confocal measurement unit comprises a monochromatic light source (e.g., a laser light source) that emits monochromatic light, an imaging optical system that focuses the monochromatic light from the monochromatic light source at a fixed focus and irradiates the WA to be measured, a pinhole member with a pinhole (micro-aperture) formed therein, and a light receiving unit that receives the monochromatic light reflected from the WA to be measured through the pinhole of the pinhole member. The third shape calculation unit 92(46) is functionally configured in the control processing unit 4B as described later in this embodiment, and processes the output of the third measurement unit 91 according to the confocal method to determine the contour shape of the peripheral part of the WA to be measured as the confocal contour shape.More specifically, the third shape calculation unit 92(46) controls the scanning drive unit to scan the confocal measurement unit along the height direction of the WA to be measured, and determines the position of the confocal measurement unit where the amount of reflected light received by the light receiving unit is maximum, based on the output of the light receiving unit, thereby determining the distance from the confocal measurement unit to the surface of the WA to be measured. Since the confocal measurement unit is a fixed focus, when it is not in focus on the surface of the WA to be measured (when it is out of focus), blurring occurs, the reflected light is substantially blocked by the pinhole, the reflected light is received by the light receiving unit near the point of focus, and when it is in focus on the surface of the WA to be measured (when it is in focus), the reflected light is received by the light receiving unit at maximum light intensity. This allows the distance to be determined. The third shape calculation unit 92(46) determines the confocal contour shape by repeating this distance measurement at predetermined intervals along the radial direction of the WA to be measured. Movement of the WA to be measured along the radial direction is performed by moving the drive unit 32 in the stage 3 in the horizontal direction.

[0082] Furthermore, in the above description, the confocal measurement unit may be configured with a slit instead of the pinhole. This eliminates the need to move the WA to be measured radially in order to determine the confocal contour shape, thereby shortening the measurement time. Also, in the above description, the confocal measurement unit may be equipped with a multicolor light source that emits multicolor light (each containing multiple wavelengths that are different from each other) instead of the monocolor light source, an imaging optical system with chromatic aberration that has different focal lengths for each of the multiple wavelengths instead of the imaging optical system, a light receiving unit for each of the multiple wavelengths, and a spectrometer that spectrally separates the reflected light into the multiple wavelengths, and each of the multiple wavelengths of light emitted from the spectrometer is received by each of the multiple light receiving units. This eliminates the need to scan the confocal measurement unit along the height direction of the WA to be measured, thereby shortening the measurement time.

[0083] In the second embodiment, as described above, the confocal contour shape measuring unit 9 corresponds to another example of the optical contour shape measuring unit that measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance from the surface direction to the object to be measured using light. The predetermined reference plane is, as described above, for example, a horizontal plane where the thickness of the object to be measured WA is halved from the shadow contour shape, and the height is determined as the length from the reference plane to the confocal contour shape by superimposing the shadow contour shape and the confocal contour shape as described later.

[0084] As shown in Figure 9, the third measuring unit 91 and the stage 3 are arranged such that when the WA to be measured is moved by the stage 3 to the confocal contour shape measurement position PS3, the periphery of the WA to be measured is illuminated by the illumination light from the third measuring unit 91 and the reflected light is received. The confocal contour shape measurement position PS3 is the position of the WA to be measured when the confocal contour shape is measured by the confocal contour shape measuring unit 9, and in this embodiment, it is the light section contour shape measurement position PS2 (PS3=PS2). The first measuring unit 11 of the shadow contour shape measuring unit 1, the third measuring unit 91 of the confocal contour shape measuring unit 9, and the stage 3 are arranged and fixed as described above.

[0085] Furthermore, the predetermined range of movement when moving the drive unit 32 horizontally in stage 3 is defined such that, for example, when the drive unit 32 moves to one end, the measurement target WA is located at the measurement position PS1 of the shadow contour shape, as shown in Figure 9, and when the drive unit 32 moves to the other end, the measurement target WA is located at the measurement position PS3 of the confocal contour shape.

[0086] The memory unit 8B is connected to the control processing unit 4B and is a circuit that stores various predetermined programs and various predetermined data in accordance with the control of the control processing unit 4B. The various predetermined programs include, for example, a second control processing program, and the second control processing program includes, for example, a second control program, a first shape calculation program similar to that of the first embodiment, a third shape calculation program, a noise reduction processing program, and a second contour shape calculation program. The second control program is a program that controls each part 1 to 3, 5 to 7, and 8B of the contour shape measuring device 1000B according to the function of each part. The third shape calculation program is a program that determines the contour shape of the peripheral part of the WA to be measured as a confocal contour shape by processing the output of the third measurement unit 91 according to the confocal method. The noise reduction program is a program that removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measuring program to determine a noise-reduced contour shape. The second contour shape calculation program is a program that determines the contour shape based on the shadow contour shape obtained by the shadow contour shape measurement program and the confocal contour shape obtained by the third shape calculation program of the confocal contour shape measurement program.

[0087] The aforementioned various predetermined data include, for example, data necessary for executing each of these programs, such as the name of the measurement target, positional relationship information, data being processed, and contour shape. The positional relationship information represents the positional relationship between the measurement position of the first measurement unit 11 in the shadow contour shape measurement unit 1 (first measurement position) and the measurement position of the third measurement unit 91 in the confocal contour shape measurement unit 9 (third measurement position). Since the shadow contour shape measurement unit 1, the confocal contour shape measurement unit 9, and the stage 3 are fixedly arranged as described above, the positional relationship between the first measurement position and the third measurement position can be predetermined, and from this positional relationship information, the shadow contour shape and the confocal contour shape at each measurement location can be made to correspond to each other.

[0088] Such a storage unit 8B may be configured to include, for example, ROM, EEPROM, RAM, etc., and may also include a hard disk drive if necessary.

[0089] The control processing unit 4B is a circuit for determining the contour shape of the WA to be measured by controlling each part 1-3, 5-7, and 8B of the contour shape measuring device 1000B according to the function of each part. The control processing unit 4B is configured, for example, with a CPU and its peripheral circuits. When the second control processing program is executed, the control unit 41B, the first shape calculation unit 42(12), the third shape calculation unit 46(92), the noise reduction processing unit 44B, and the contour shape calculation unit 45B are functionally configured in the control processing unit 4B. The first shape calculation unit 42(12) in this second embodiment is the same as the first shape calculation unit 42(12) in the first embodiment, so its description is omitted.

[0090] The control unit 41B controls each of the contour shape measuring device 1000B parts 1-3, 5-7, and 8B according to the function of each part, and is in charge of the overall control of the contour shape measuring device 1000B.

[0091] As described above, the third shape calculation unit 46(92) processes the output of the third measurement unit 91 according to the confocal method to determine the contour shape of the peripheral part of the WA to be measured as the confocal contour shape. For each of the measurement locations, the confocal contour shape of that measurement location is generated.

[0092] The noise reduction processing unit 44B removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement unit 9 to obtain a noise-reduced contour shape. More specifically, the noise reduction processing unit 44B can be configured in the above-described noise reduction processing unit 44A by replacing the light section contour shape measurement unit 2 with the confocal contour shape measurement unit 9 and replacing the light section contour shape with the confocal contour shape.

[0093] The contour shape calculation unit 45B determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the confocal contour shape measured by the confocal contour shape measurement unit 9. In this embodiment, a noise reduction processing unit 44B is provided, so the contour shape calculation unit 45B determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the noise reduction contour shape obtained by the noise reduction processing unit 44B from the confocal cross-sectional contour shape measured by the confocal contour shape measurement unit 9.

[0094] More specifically, the contour shape calculation unit 45B retrieves (reads) the shadow contour shape measured by the shadow contour shape measurement unit 1 and the confocal contour shape (noise-reduced contour shape in this embodiment) measured by the confocal contour shape measurement unit 9 at the same measurement location from the storage unit 8B based on the positional relationship information, and performs alignment to superimpose these shadow contour shapes and confocal contour shapes. The alignment is similar to that of the first embodiment, and is performed, for example, by detecting the step position from the shadow contour shape and the step position from the confocal contour shape, and making these step positions coincide with each other. The contour shape calculation unit 45B then divides the predetermined measurement range for determining the contour shape of the periphery including the step into a plurality of divisions, and for each of the plurality of divisions, it determines the contour shape of the periphery by selecting either the shadow contour shape or the confocal contour shape (noise-reduced contour shape in this embodiment). In the selection process described above, for example, if both a shadow contour shape and a confocal contour shape exist in a given section, the confocal contour shape is selected. If a shadow contour shape exists but a confocal contour shape does not, the shadow contour shape is selected. However, if a confocal contour shape exists in only a portion of a given section, that section is considered to be without a confocal contour shape. Shortening the length of the section reduces the number of such cases.

[0095] In the second embodiment, the noise reduction processing unit 44B corresponds to another example of a noise reduction processing unit that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape.

[0096] These control processing units 4B, input unit 5, output unit 6, IF unit 7, and storage unit 8B can be configured using, for example, a desktop or notebook computer.

[0097] Next, the operation of this embodiment will be described. Figure 10 is a flowchart showing the operation of the contour shape measuring device in the second embodiment.

[0098] When the contour shape measuring device 1000B with this configuration is powered on, it performs the initialization of each necessary part and starts operation. The control processing unit 4B is functionally configured with the control unit 41B, the first shape calculation unit 42(12), the third shape calculation unit 46(92), and the contour shape calculation unit 45B through the execution of its second control processing program.

[0099] When the WA to be measured is set on stage 3 and measurement begins, in Figure 10, first, the contour shape measuring device 1000B executes a process S11 similar to the process S1 of the first embodiment by the control unit 41B of the control processing unit 4B, and then the first shape calculation unit 42(12) of the control processing unit 4B executes a process S12 similar to the process S3 of the first embodiment.

[0100] Next, the contour shape measuring device 1000B uses the confocal contour shape measuring unit 9 to determine the contour shape of the peripheral part of the WA to be measured as the confocal contour shape at the confocal contour shape measurement position PS3 (=PS2) by processing the output of the third measuring unit 91 according to the confocal method, and stores it in the storage unit 8B (S13). The stage 3 rotates the WA to be measured sequentially at the predetermined angular interval (the sampling interval), and each confocal contour shape is measured at each measurement point (the sampling point) in the circumferential direction and stored in association with each measurement point.

[0101] Next, the contour shape measuring device 1000B removes noise from the optical section contour shape using the noise removal processing unit 44B of the control processing unit 4B, obtains a noise-removed contour shape, and stores it in the storage unit 8B (S14). For each of the measurement locations, a noise-removed contour shape is obtained and stored in association with each measurement location.

[0102] Next, the contour shape measuring device 1000B determines the final contour shape using the contour shape calculation unit 45B of the control processing unit 4B and stores it in the storage unit 8B (S15). For each of the measurement points, the final contour shape is determined and stored in association with each measurement point.

[0103] Then, the contour shape measuring device 1000B outputs the contour shape of each measurement point to the output unit 6 via the control unit 41B of the control processing unit 4B (S16), and the process ends. If necessary, each contour shape may be output to an external device via the IF unit 7.

[0104] As described above, the contour shape measuring device 1000B and the contour shape measuring method implemented therein, in addition to measuring the shadow contour shape, also measure the light contour shape, and in the second embodiment, the confocal contour shape. Since the contour shape is determined based on the shadow contour shape obtained by measuring the shadow contour shape and the confocal contour shape obtained by measuring the confocal contour shape, the contour shape can be measured with greater accuracy.

[0105] Next, another embodiment will be described. (Third embodiment) In the first embodiment, the light section contour shape measuring unit 2 was used as the light contour shape measuring unit, and in the second embodiment, the confocal contour shape measuring unit 9 was used as the light contour shape measuring unit. In the third embodiment, both the light section contour shape measuring unit 2 and the confocal contour shape measuring unit 9 are used as the light contour shape measuring unit. That is, the contour shape measuring device in the third embodiment comprises a shadow contour shape measuring unit, a light section contour shape measuring unit, a confocal contour shape measuring unit, and a contour shape calculation unit, similar to those described above. The light section contour shape measuring unit in the third embodiment measures the contour shape of the peripheral portion as the light section contour shape by light section method from the direction of one of the surfaces of the object to be measured, which is one surface and the other surface facing the one surface. The confocal contour shape measuring unit in the third embodiment measures the contour shape of the peripheral portion as the confocal contour shape by confocal method from the direction of the other surface. The contour shape calculation unit of the third embodiment determines the contour shape on one side based on the shadow contour shape measured by the shadow contour shape measuring unit and the light section contour shape measured by the light section contour shape measuring unit, and determines the contour shape on the other side based on the shadow contour shape measured by the shadow contour shape measuring unit and the confocal contour shape measured by the confocal contour shape measuring unit. A more detailed explanation follows.

[0106] Figure 11 is a block diagram showing the configuration of the contour shape measuring device in the third embodiment. Figure 12 is a schematic diagram illustrating the measurement system in the contour shape measuring device of the third embodiment.

[0107] The contour shape measuring device 1000C in the third embodiment includes, for example, a shadow contour shape measuring unit 1, a light section contour shape measuring unit 2, a confocal contour shape measuring unit 9, a stage 3, a control processing unit 4C, an input unit 5, an output unit 6, an interface unit (IF unit) 7, and a storage unit 8C, as shown in Figures 11 and 12. The shadow contour shape measuring unit 1, the light section contour shape measuring unit 2, the stage 3, the input unit 5, the output unit 6, and the IF unit 7 in the contour shape measuring device 1000C of the third embodiment are the same as the shadow contour shape measuring unit 1, the light section contour shape measuring unit 2, the stage 3, the input unit 5, the output unit 6, and the IF unit 7 in the contour shape measuring device 1000A of the first embodiment, so their description is omitted. The confocal contour shape measuring unit 9 in the contour shape measuring device 1000C of the third embodiment is the same as the confocal contour shape measuring unit 9 in the contour shape measuring device 1000B of the second embodiment, so its description is omitted.

[0108] In the third embodiment, as described above, the light section contour shape measuring unit 2 and the confocal contour shape measuring unit 9 correspond to another example of the light contour shape measuring unit that measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance from the surface direction to the object to be measured using light.

[0109] As shown in Figure 12, the second measuring unit 21 and stage 3 are arranged such that when the WA to be measured is moved by stage 3 to the measurement position PS2 (=PS3) of the optical section contour shape, one of the two faces (one main face) of the WA to be measured, for example, on the back surface of the WA to be measured in the example shown in Figure 12, the extension direction of the slit-shaped illumination light from the second measuring unit 21 (the direction in which the illumination light extends in a slit shape) coincides with the radial direction X of the WA to be measured, and the peripheral edge of the WA to be measured is illuminated by the slit-shaped illumination light from the second measuring unit 21. As shown in Figure 12, the third measuring unit 91 and stage 3 are arranged such that when the WA to be measured is moved by stage 3 to the measurement position PS3 (=PS2) of the confocal contour shape, the peripheral edge of the WA to be measured is illuminated by the illumination light from the third measuring unit 91 and the reflected light is received on the other face of the WA to be measured, for example, on the front surface of the WA to be measured in the example shown in Figure 12. The first measuring unit 11 of the shadow contour shape measuring unit 1, the second measuring unit 21 of the light section contour shape measuring unit 2, the third measuring unit 91 of the confocal contour shape measuring unit 9, and the stage 3 are arranged and fixed as described above.

[0110] Furthermore, the predetermined range of movement when moving the drive unit 32 horizontally in stage 3 is defined such that, for example, when the drive unit 32 moves to one end, the measurement target WA is located at the measurement position PS1 of the shadow contour shape, as shown in Figure 12, and when the drive unit 32 moves to the other end, the measurement target WA is located at the measurement position PS3 (=PS2) of the confocal contour shape.

[0111] The memory unit 8C is connected to the control processing unit 4C and is a circuit that stores various predetermined programs and various predetermined data in accordance with the control of the control processing unit 4C. The various predetermined programs include, for example, a third control processing program, and the third control processing program includes, for example, a third control program, first and second shape calculation programs similar to those in the first embodiment, a third shape calculation program similar to those in the second embodiment, a noise reduction processing program, and a third contour shape calculation program. The third control program is a program that controls each part 1 to 3, 5 to 7, and 8C of the contour shape measuring device 1000C according to the function of each part. The noise reduction processing program is a program that removes noise generated in the height direction from the light section contour shape measured by the light section contour shape measurement program to obtain a first noise-reduced contour shape, and removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement program to obtain a second noise-reduced contour shape. The third contour shape calculation program determines the contour shape on one side based on the shadow contour shape obtained by the first shape calculation program of the shadow contour shape measurement program and the light section contour shape obtained by the second shape calculation program of the light section contour shape measurement program, and determines the contour shape on the other side based on the shadow contour shape and the confocal contour shape obtained by the third shape calculation program of the confocal contour shape measurement program.

[0112] The aforementioned various predetermined data include, for example, data necessary for executing each of these programs, such as the name of the measurement target, positional relationship information, data being processed, and contour shape. The positional relationship information represents the positional relationship between the measurement position of the first measurement unit 11 in the shadow contour shape measurement unit 1 (first measurement position), the measurement position of the second measurement unit 21 in the light section contour shape measurement unit 2 (second measurement position), and the measurement position of the third measurement unit 91 in the confocal contour shape measurement unit 9 (third measurement position). Since the shadow contour shape measurement unit 1, the light section contour shape measurement unit 2, the confocal contour shape measurement unit 9, and the stage 3 are fixedly arranged as described above, the positional relationship between the first measurement position, the second measurement position, and the third measurement position can be predetermined, and from this positional relationship information, the shadow contour shape, light section contour shape, and confocal contour shape at each measurement location can be made to correspond to each other.

[0113] Such a storage unit 8C may include, for example, ROM, EEPROM, RAM, etc., and may also include a hard disk drive if necessary.

[0114] The control processing unit 4C is a circuit for determining the contour shape of the WA to be measured by controlling each part 1-3, 5-7, and 8C of the contour shape measuring device 1000C according to the function of each part. The control processing unit 4C is configured, for example, with a CPU and its peripheral circuits. When the third control processing program is executed, the control unit 41C, the first shape calculation unit 42(12), the second shape calculation unit 43(22), the third shape calculation unit 46(92), the noise reduction processing unit 44C, and the contour shape calculation unit 45C are functionally configured in the control processing unit 4C. The first shape calculation unit 42(12) in the third embodiment is the same as the first shape calculation unit 42(12) in the first embodiment, so its description is omitted. The second shape calculation unit 43(22) in the third embodiment is the same as the second shape calculation unit 43(22) in the first embodiment, except that it determines the contour shape of the peripheral edge on one side of the WA to be measured (the back side in the example shown in Figure 12), so its description is omitted. The third shape calculation unit 46(92) in the third embodiment is the same as the third shape calculation unit 46(92) in the second embodiment, except that it determines the contour shape of the peripheral edge on the other side of the WA to be measured (the front side in the example shown in Figure 12), so its description is omitted.

[0115] The control unit 41C controls each of the contour shape measuring device 1000C parts 1-3, 5-7, and 8C according to the function of each part, and is in charge of the overall control of the contour shape measuring device 1000C.

[0116] The noise reduction processing unit 44C removes noise generated in the height direction from the light section contour shape measured by the light section contour shape measuring unit 2 to obtain a first noise reduction contour shape on one side, and removes noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measuring unit 9 to obtain a second noise reduction contour shape on the other side. The noise reduction processing unit 44C obtains the first noise reduction contour shape on one side by the same process as the noise reduction processing unit 44A in the first embodiment, so the explanation is omitted. The noise reduction processing unit 44C obtains the second noise reduction contour shape on the other side by the same process as the noise reduction processing unit 44B in the second embodiment, so the explanation is omitted.

[0117] The contour shape calculation unit 45C determines the contour shape on one side based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the light section contour shape measured by the light section contour shape measurement unit 2, and determines the contour shape on the other side based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the confocal contour shape measured by the confocal contour shape measurement unit 9. More specifically, the contour shape calculation unit 45C determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit 1 and the first noise-reduced contour shape obtained by the noise reduction processing unit from the light section contour shape measured by the light section contour shape measurement unit 2, and the second noise-reduced contour shape obtained by the noise reduction processing unit from the confocal contour shape measured by the confocal contour shape measurement unit 9. The contour shape calculation unit 45C determines the contour shape on one side based on the shadow contour shape measured by the shadow contour shape measuring unit 1 and the light section contour shape measured by the light section contour shape measuring unit 2 by the same process as the contour shape calculation unit 45A in the first embodiment, so its explanation is omitted. The contour shape calculation unit 45C determines the contour shape on the other side based on the shadow contour shape measured by the shadow contour shape measuring unit 1 and the confocal contour shape measured by the confocal contour shape measuring unit 9 by the same process as the contour shape calculation unit 45B in the second embodiment, so its explanation is omitted. The contour shape calculation unit 45C may determine the contour shape of the peripheral part of the WA to be measured by integrating the contour shape on one side and the contour shape on the other side obtained by using the contour shape of the tip portion of the WA to be measured.

[0118] In the third embodiment, the noise reduction processing unit 44C corresponds to an example of a noise reduction processing unit that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape.

[0119] These control processing units 4C, input unit 5, output unit 6, IF unit 7, and storage unit 8C can be configured by, for example, a desktop or notebook computer.

[0120] Next, the operation of this embodiment will be described. Figure 13 is a flowchart showing the operation of the contour shape measuring device in the third embodiment.

[0121] When the contour shape measuring device 1000C with this configuration is powered on, it performs the initialization of each necessary part and starts operation. The control processing unit 4C is functionally configured with the control unit 41C, the first shape calculation unit 42(12), the second shape calculation unit 43(22), the third shape calculation unit 46(92), the noise reduction processing unit 44C, and the contour shape calculation unit 45C through the execution of its third control processing program.

[0122] When the WA to be measured is set on stage 3 and measurement begins, as shown in Figure 13, first, the contour shape measuring device 1000C, through the control unit 41C of the control processing unit 4C, executes a process S21 similar to the process S1 of the first embodiment. Subsequently, the control unit 41C of the control processing unit 4C executes a process S22 similar to the process S2 of the first embodiment on one side of the WA to be measured. Subsequently, the first shape calculation unit 42(12) of the control processing unit 4C executes a process S23 similar to the process S3 of the first embodiment. Subsequently, the second shape calculation unit 43(22) of the control processing unit 4C executes a process S24 similar to the process S4 of the first embodiment on one side of the WA to be measured. Subsequently, the third shape calculation unit 46(92) of the control processing unit 4C executes a process S25 similar to the process S13 of the second embodiment on the other side of the WA to be measured.

[0123] Next, the contour shape measuring device 1000C, using the noise reduction processing unit 44C of the control processing unit 4C, performs a process S26 on one side of the WA to be measured, similar to the process S5 of the first embodiment, and performs a process S26 on the other side of the WA to be measured, similar to the process S14 of the second embodiment.

[0124] Next, the contour shape measuring device 1000C determines the final contour shape using the contour shape calculation unit 45C of the control processing unit 4C and stores it in the storage unit 8C (S27). For each of the measurement points, the final contour shape is determined and stored in association with each measurement point.

[0125] Then, the contour shape measuring device 1000C outputs the contour shape of each measurement point to the output unit 6 via the control unit 41C of the control processing unit 4C (S28), and the process ends. If necessary, each contour shape may be output to an external device via the IF unit 7.

[0126] In the example shown in Figure 12, the contour shape measuring device 1000C is configured to measure the contour shape of the peripheral portion on the surface of the WA to be measured with the confocal contour shape measuring unit 9 and the contour shape of the peripheral portion on the back surface of the WA to be measured with the light section contour shape measuring unit 2. However, the contour shape measuring device 1000C may also be configured to measure the contour shape of the peripheral portion on the back surface of the WA to be measured with the confocal contour shape measuring unit 9 and the contour shape of the peripheral portion on the surface of the WA to be measured with the light section contour shape measuring unit 2. Such a contour shape measuring device can be substantially realized with the configuration of the contour shape measuring device 1000C shown in Figure 12 by flipping the WA to be measured, which was placed on the stage 3 with its back surface in contact with it, and placing it on the stage 3.

[0127] As described above, the contour shape measuring device 1000C and the contour shape measuring method implemented therein, in addition to measuring the shadow contour shape, measure the light section contour shape on one side of the WA to be measured as a measurement of the light contour shape, and determine the contour shape on the one side based on the shadow contour shape obtained from the measurement of the shadow contour shape and the light section contour shape obtained from the measurement of the light section contour shape. Furthermore, the contour shape measuring device 1000C and the contour shape measuring method, in addition to measuring the shadow contour shape, measure the confocal contour shape on the other side of the WA to be measured as a measurement of the light contour shape, and determine the contour shape on the other side based on the shadow contour shape obtained from the measurement of the shadow contour shape and the confocal contour shape obtained from the measurement of the confocal contour shape. For this reason, the contour shape measuring device 1000C and the contour shape measuring method can measure the contour shapes on both sides of the peripheral portion with greater accuracy.

[0128] Furthermore, in measuring the contour shape of each side of the WA to be measured, the light section method may be used on both sides, or the confocal method may be used on both sides.

[0129] To illustrate the present invention, the embodiments have been adequately and fully described above with reference to the drawings. However, those skilled in the art should recognize that it is easy to modify and / or improve upon the above embodiments. Therefore, unless such modifications or improvements implemented by those skilled in the art fall outside the scope of the claims, such modifications or improvements shall be considered to be included within the scope of the claims. [Explanation of Symbols]

[0130] 1000A, 1000B, 1000C Contour Shape Measuring Device 1. Shadow contour shape measurement unit 2. Light section contour shape measurement unit 3 stages 4A, 4B, 4C Control Processing Units 5 Input section 6 Output section 7. Interface Section (IF Section) 8A, 8B, 8C storage section 9. Confocal contour shape measurement unit 11 1st measurement section 12(42) 1st shape calculation section 21 2nd measurement section 22(43) Second shape calculation section 41 Control Unit 44A, 44B, 44C Noise reduction processing unit 45A, 45B, 45C Contour shape calculation unit 91 Third measurement section 92(46) Third shape calculation section

Claims

1. A contour shape measuring device for measuring the contour shape of a disc-shaped object whose peripheral edge has been beveled, A shadow contour shape measuring unit measures the contour shape as a shadow contour shape based on a shadow image captured of the shadow of the peripheral edge that is generated by shining light on the peripheral edge from the tangential direction of the outer circumference, An optical contour shape measuring unit measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction, The system includes a contour shape calculation unit that determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the light contour shape measured by the light contour shape measuring unit, The contour shape calculation unit, for each step of the beveling process, selects either the shadow contour shape or the light contour shape within a predetermined range including the step to determine the contour shape, and uses the shadow contour shape as the contour shape in the range excluding the predetermined range for each step to determine the contour shape. Contour shape measuring device.

2. The optical contour shape measuring unit is an optical section contour shape measuring unit that measures the optical contour shape as an optical section contour shape by optical section method from the surface direction. The contour shape measuring device according to claim 1.

3. The optical contour shape measuring unit is a confocal contour shape measuring unit that measures the optical contour shape as a confocal contour shape from the surface direction using the confocal method. The contour shape measuring device according to claim 1.

4. The optical contour shape measuring unit is A light section contour shape measuring unit that measures the contour shape of the peripheral portion as a light section contour shape from the direction of one of the surfaces of the object to be measured, one surface and the other surface facing the one surface, from the surface direction of the one surface, The system includes a confocal contour shape measuring unit that measures the contour shape of the peripheral portion as a confocal contour shape from the surface direction of the other surface using the confocal method, The contour shape calculation unit, The contour shape on one side is determined based on the shadow contour shape measured by the shadow contour shape measuring unit and the light section contour shape measured by the light section contour shape measuring unit, and the contour shape on the other side is determined based on the shadow contour shape measured by the shadow contour shape measuring unit and the confocal contour shape measured by the confocal contour shape measuring unit. The contour shape measuring device according to claim 1.

5. The system further includes a noise reduction processing unit that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape. The contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement unit and the noise-reduced contour shape obtained by the noise reduction processing unit from the light contour shape measured by the light contour shape measurement unit. The contour shape measuring device according to claim 1.

6. The noise reduction processing unit removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measuring unit. The contour shape measuring device according to claim 5.

7. A contour shape measurement method for measuring the contour shape of a disc-shaped object to be measured, in which the peripheral edge has been beveled, A shadow contour shape measurement step, in which the contour shape is measured as a shadow contour shape based on a shadow image obtained by capturing the shadow of the peripheral edge that is created by shining light on the peripheral edge from the tangential direction of the outer circumference, A light contour shape measurement step, which measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction, The system includes a contour shape calculation step that determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the light contour shape measured by the light contour shape measurement step. The contour shape calculation step involves, for each step of the beveling process, selecting either the shadow contour shape or the light contour shape within a predetermined range including the step to determine the contour shape, and using the shadow contour shape as the contour shape in the range excluding the predetermined range for each step to determine the contour shape. Contour shape measurement method.

8. The aforementioned optical contour shape measurement step is an optical section contour shape measurement step in which the optical contour shape is measured as an optical section contour shape by an optical section method from the surface direction. The contour shape measurement method according to claim 7.

9. The optical contour shape measurement step is a confocal contour shape measurement step in which the optical contour shape is measured as a confocal contour shape from the surface direction by the confocal method. The contour shape measurement method according to claim 7.

10. The optical contour shape measurement step is, A light section contour shape measurement step, in which the contour shape of the peripheral portion is measured as a light section contour shape from the direction of one of the surfaces of the object to be measured, one surface and the other surface facing the one surface, from the surface direction of the one surface, The system includes a confocal contour shape measurement step, in which the contour shape of the peripheral portion is measured as a confocal contour shape from the surface direction of the other surface by the confocal method, The contour shape calculation step is, The contour shape on one side is determined based on the shadow contour shape measured by the shadow contour shape measurement step and the light section contour shape measured by the light section contour shape measurement step, and the contour shape on the other side is determined based on the shadow contour shape measured by the shadow contour shape measurement step and the confocal contour shape measured by the confocal contour shape measurement step. The contour shape measurement method according to claim 7.

11. The process further comprises a noise reduction process that removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measurement process to obtain a noise-reduced contour shape, The contour shape calculation step determines the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the noise-removed contour shape obtained in the noise removal processing step from the light contour shape measured by the light contour shape measurement step. The contour shape measurement method according to claim 7.

12. The noise reduction process removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measurement process. The contour shape measurement method according to claim 11.

13. A contour shape measuring device for measuring the contour shape of a disc-shaped object to be measured, the peripheral edge of which has been beveled, A shadow contour shape measuring unit measures the contour shape as a shadow contour shape based on a shadow image captured of the shadow of the peripheral edge that is generated by shining light on the peripheral edge from the tangential direction of the outer circumference, An optical contour shape measuring unit measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction, A noise reduction processing unit removes noise generated in the height direction from the optical contour shape measured by the optical contour shape measuring unit to obtain a noise-reduced contour shape, The contour shape calculation unit determines the contour shape based on the shadow contour shape measured by the shadow contour shape measuring unit and the noise-reduced contour shape obtained by the noise reduction processing unit from the light contour shape measured by the light contour shape measuring unit. The noise reduction processing unit removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measuring unit. Contour shape measuring device.

14. The optical contour shape measuring unit is an optical section contour shape measuring unit that measures the optical contour shape as an optical section contour shape by an optical section method from the surface direction. The contour shape measuring device according to claim 13.

15. The optical contour shape measuring unit is a confocal contour shape measuring unit that measures the optical contour shape as a confocal contour shape from the surface direction by the confocal method, The contour shape measuring device according to claim 13.

16. The optical contour shape measuring unit is A light section contour shape measuring unit that measures the contour shape of the peripheral portion as a light section contour shape from the direction of one of the surfaces of the object to be measured, one surface and the other surface facing the one surface, from the surface direction of the one surface, The system includes a confocal contour shape measuring unit that measures the contour shape of the peripheral portion as a confocal contour shape from the surface direction of the other surface using the confocal method, The noise reduction processing unit is The first noise-removed contour shape is obtained by removing the first noise generated in the height direction from the light section contour shape measured by the light section contour shape measuring unit, and the second noise-removed contour shape is obtained by removing the second noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measuring unit. The contour shape calculation unit, Based on the shadow contour shape measured by the shadow contour shape measuring unit and the light section contour shape measured by the light section contour shape measuring unit, the first noise-reduced contour shape obtained by the noise reduction processing unit is determined, and based on the shadow contour shape measured by the shadow contour shape measuring unit and the second noise-reduced contour shape obtained by the noise reduction processing unit, the contour shape on the other side is determined. The noise reduction processing unit removes the first noise using a first threshold value corresponding to the height variation determined based on the light section contour shape measured by the light section contour shape measuring unit, and removes the second noise using a second threshold value corresponding to the height variation determined based on the light section contour shape measured by the confocal contour shape measuring unit. The contour shape measuring device according to claim 13.

17. A method for measuring the contour shape of a disc-shaped object to be measured, the peripheral edge of which has been beveled, A shadow contour shape measurement step, in which the contour shape is measured as a shadow contour shape based on a shadow image obtained by capturing the shadow of the peripheral edge that is created by shining light on the peripheral edge from the tangential direction of the outer circumference, A light contour shape measurement step, which measures the contour shape of the peripheral portion as an optical contour shape by measuring the distance to the object to be measured using light from the surface direction, A noise reduction process to obtain a noise-reduced contour shape by removing noise generated in the height direction from the optical contour shape measured by the optical contour shape measurement process, The contour shape calculation step includes determining the contour shape based on the shadow contour shape measured by the shadow contour shape measurement step and the noise-removed contour shape obtained in the noise removal processing step from the light contour shape measured by the light contour shape measurement step, The noise reduction process removes the noise using a threshold value corresponding to the height variation obtained based on the optical contour shape measured by the optical contour shape measurement process. Contour shape measurement method.

18. The optical contour shape measurement step is an optical section contour shape measurement step in which the optical contour shape is measured as an optical section contour shape by an optical section method from the surface direction. The contour shape measurement method according to claim 17.

19. The optical contour shape measurement step is a confocal contour shape measurement step in which the optical contour shape is measured as a confocal contour shape from the surface direction by the confocal method, The contour shape measurement method according to claim 17.

20. The optical contour shape measurement step is: A light section contour shape measurement step, in which the contour shape of the peripheral portion is measured as a light section contour shape from the direction of one of the surfaces of the object to be measured, one surface and the other surface facing the one surface, from the surface direction of the one surface, The system includes a confocal contour shape measurement step, in which the contour shape of the peripheral portion is measured as a confocal contour shape from the surface direction of the other surface by the confocal method, The noise reduction process described above is: A first noise-removed contour shape is obtained by removing a first noise generated in the height direction from the light section contour shape measured by the light section contour shape measurement step, and a second noise-removed contour shape is obtained by removing a second noise generated in the height direction from the confocal contour shape measured by the confocal contour shape measurement step. The contour shape calculation step is, The contour shape on one side is determined based on the shadow contour shape measured by the shadow contour shape measurement step and the first noise-reduced contour shape obtained in the noise reduction processing step from the light section contour shape measured by the light section contour shape measurement step, and the contour shape on the other side is determined based on the second noise-reduced contour shape obtained in the noise reduction processing step from the shadow contour shape measured by the shadow contour shape measurement step and the confocal contour shape measured by the confocal contour shape measurement step. The noise reduction process removes the first noise using a first threshold value corresponding to the height variation obtained based on the light section contour shape measured by the light section contour shape measurement process, and removes the second noise using a second threshold value corresponding to the height variation obtained based on the light section contour shape measured by the confocal contour shape measurement process. The contour shape measurement method according to claim 17.

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