KR20200140715A - Pattern measuring device, inclination calculating method in pattern measuring device, and pattern measuring method - Google Patents

Abstract

An object of the present invention is to provide a technique capable of accurately measuring a pattern shape. According to an embodiment of the present invention, provided is a pattern measuring device comprising a transport unit, a pattern projection unit, an image capturing unit, and a measuring unit. The transport unit transports a substrate. The pattern projection unit is disposed above the transport unit and projects a projection pattern onto the substrate transported by the transport unit. The imaging capturing unit is disposed above the transport unit and captures an image of the projection pattern projected onto the substrate or an actual pattern formed on the substrate. The measuring unit measures a shape of the projection pattern or the actual pattern based on the image captured by the image capturing unit.

Description

A pattern measuring device, a tilt calculation method in a pattern measuring device, and a pattern measuring method TECHNICAL FIELD {PATTERN MEASURING DEVICE, INCLINATION CALCULATING METHOD IN PATTERN MEASURING DEVICE, AND PATTERN MEASURING METHOD}

The present disclosure relates to a pattern measuring device, a tilt calculation method, and a pattern measuring method in a pattern measuring device.

Patent Literature 1 discloses a pattern measuring apparatus for photographing a substrate conveyed by a conveying unit by an imaging unit disposed above the conveying unit, and measuring the shape of a pattern formed on the substrate based on the captured image.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2015-72257

The present disclosure provides a technique capable of accurately measuring a pattern shape.

A pattern measurement device according to an aspect of the present disclosure includes a conveyance unit, a pattern projection unit, an imaging unit, and a measurement unit. The conveying unit conveys the substrate. The pattern projection unit is disposed above the transport unit and projects the projection pattern onto the substrate transported by the transport unit. The imaging unit is disposed above the transport unit and captures a projection pattern projected onto the substrate or an actual pattern formed on the substrate. The measurement unit measures the shape of a projection pattern or an actual pattern based on the image picked up by the imaging unit.

According to the present disclosure, a pattern shape can be accurately measured.

1 is a schematic explanatory diagram showing a configuration of a substrate processing system according to an embodiment.
2 is a schematic perspective view showing a configuration of a line width measuring device according to an embodiment.
3 is a diagram showing an example of a projection pattern.
4 is a block diagram of a measurement control device according to an embodiment.
5 is a diagram showing an example of a relative angle calculation process by a calculation unit.
6 is an enlarged view of a periphery of a first figure among measurement regions according to the embodiment.
FIG. 7 is a diagram showing an example of a first graphic image captured in a state in which the first graphic is not in focus.
8 is a flowchart showing the procedure of the relative angle calculation processing according to the embodiment.
9 is a flowchart showing a procedure of measurement processing according to the embodiment.
10 is a flowchart showing an example of a procedure of correction processing according to the embodiment.
11 is a flowchart showing another example of the procedure of correction processing according to the embodiment.

Hereinafter, with reference to the accompanying drawings, an embodiment of a pattern measurement device disclosed by the present application, a tilt calculation method and a pattern measurement method in the pattern measurement device will be described in detail. In addition, the pattern measurement apparatus disclosed by the embodiment shown below, the inclination calculation method, and the pattern measurement method in a pattern measurement apparatus are not limited.

<1. Substrate processing system>

First, a configuration of a substrate processing system 1 according to an embodiment will be described with reference to FIG. 1. 1 is a schematic explanatory diagram showing a configuration of a substrate processing system 1 according to an embodiment.

In the substrate processing system 1 according to the embodiment shown in Fig. 1, a substrate to be processed such as a glass substrate (hereinafter referred to as "substrate G". Not shown in Fig. 1) is subjected to, for example, a photolithography process. This is a unit that performs a process of forming a pattern. On the other hand, the substrate processing system 1 may form a pattern by a process other than a photolithography process.

The substrate processing system 1 includes a resist coating device 11, a reduced pressure drying device 12, a prebaking device 13, a cooling device 14, an exposure device 15, and a local exposure device ( 16), a developing device 17, and a line width measuring device 18 are provided. These devices 11 to 18 are integrally connected in the order of the devices 11 to 18 in, for example, the X-axis positive direction. On the other hand, the arrangement of the devices 11 to 18 is not limited to the illustrated example. For example, each of the devices 11 to 18 may be arranged in a plurality of rows, such as two rows parallel to the X axis.

Each of the above-described devices 11 to 18 transports the substrate G in the X-axis positive direction by a transport mechanism. The conveying mechanism is, for example, a conveying mechanism such as a roller conveyor, a belt conveyor, or a chain conveyor. In addition, the conveyance mechanism may be a floating type conveyance mechanism. The floating type conveyance mechanism, for example, supports the end of the substrate G from below, and sprays compressed air from below toward the substrate G to move the substrate G while holding the substrate G horizontally. .

While the substrate G is conveyed by the conveying mechanism, a pattern is formed through the inside of each of the devices 11 to 18. In this way, in the substrate processing system 1, each of the devices 11 to 18 is inlined to perform a photolithography process. In addition, in the substrate processing system 1, the substrates G are sequentially flowed by the transfer mechanism at predetermined intervals or at predetermined intervals.

The resist coating device 11 applies a photosensitive resist to the substrate G. That is, the resist coating device 11 forms a resist film on the substrate G. On the other hand, as a resist, either of a positive resist and a negative resist can be applied.

The vacuum drying apparatus 12 arranges the substrate G in the reduced pressure chamber, and dries the resist film formed on the substrate G. The prebaking device 13 heats the substrate G to evaporate the solvent in the resist film, and fixes the resist film on the substrate G. The cooling device 14 cools the substrate G heated by the prebaking device 13 to a predetermined temperature.

The exposure apparatus 15 exposes the resist film formed on the substrate G in a predetermined pattern using a mask. The local exposure apparatus 16 locally exposes the resist film, for example, in order to suppress the occurrence of fluctuations in the pattern formed on the substrate G. That is, for example, if the line width of the pattern formed on the substrate G is different with respect to the desired line width, the local exposure apparatus 16 locally exposes a portion where the line width of the pattern is different with respect to the desired line width, Correct the line width.

The developing apparatus 17 performs a development process by immersing the substrate G exposed by the exposure apparatus 15 and the local exposure apparatus 16 in a developing solution to form a pattern on the substrate G. The line width measuring device 18 measures the line width of the pattern formed on the substrate G by the developing process in the developing device 17.

On the other hand, in the above, the pattern to be measured is the line width of the pattern, but this is an example and is not limited. That is, any pattern may be used as long as it relates to the shape of the pattern. Specifically, the pattern to be measured may be, for example, the shape of the pattern such as dimensions such as the length or thickness of the pattern, curvature, layout, and further defects or deformation of the pattern.

<2. Configuration of line width measuring device>

Next, the configuration of the line width measuring device 18 will be described with reference to FIG. 2. 2 is a schematic perspective view showing a configuration of a line width measuring device 18 according to an embodiment. On the other hand, hereinafter, as shown in Fig. 2, the Y-axis direction and the Z-axis direction orthogonal to the above-described X-axis direction are defined, and the positive Z-axis direction is a vertically upward direction. In addition, the direction including the X axis and the Y axis is set as the horizontal direction.

The line width measuring device 18 includes a conveying unit 20, an imaging unit 30, a moving unit 40, and a measurement control device 50.

The conveying unit 20 is a part of the conveying mechanism of the substrate processing system 1 described above, and is, for example, a roller conveyor. The conveyance part 20 conveys the board|substrate G arrange|positioned on the roller 21 in the horizontal direction, specifically, in the positive direction of an X-axis by rotating a number of rollers 21. In addition, in FIG. 2, the roller 21 is shown through seeing.

The conveyance part 20 conveys the board|substrate G carried out from the developing apparatus 17 arrange|positioned at the front end of the line width measuring apparatus 18 in the substrate processing system 1. The operation of the conveyance unit 20, in detail, the rotational operation of the roller 21 is controlled by the measurement control device 50.

In addition, in the conveyance part 20, near the conveyance surface which conveys the board|substrate G, the board|substrate position detection part 22 shown by the broken line in FIG. 2 is arrange|positioned in plural (for example, four). The substrate position detection unit 22 outputs a detection signal to the measurement control device 50 when the substrate G is positioned above. As the substrate position detection unit 22, for example, an optical load sensor is used.

The substrate position detection unit 22 is disposed so as to be positioned below the substrate G when the substrate G is disposed at a predetermined position. The predetermined position is a position at which the pattern of the substrate G can be imaged by the imaging unit 30. On the other hand, the number of substrate position detection units 22 may be 3 or less, or 5 or more.

The imaging unit 30 is disposed above the transfer unit 20 in the Z-axis direction, and captures a pattern of the substrate G disposed on the transfer unit 20 from above. As the imaging unit 30, for example, a CCD (Charge Coupled Device) camera can be used. Information of an image (hereinafter referred to as "image information") obtained by imaging by the imaging unit 30 is input to the measurement control device 50. The imaging unit 30 starts imaging based on the signal output from the measurement control device 50 and performs imaging.

In the vicinity of the imaging unit 30, a camera height measuring unit 31 is provided. The camera height measuring unit 31 measures the height in the Z-axis direction from the lens of the imaging unit 30 to the pattern surface (upper surface) Ga on which the pattern is formed on the substrate G. The measurement result by the camera height measurement unit 31 is input to the measurement control device 50 and is used to adjust the height of the imaging unit 30. On the other hand, as the camera height measuring unit 31, for example, a laser displacement meter is used.

Further, in the vicinity of the imaging unit 30, a pattern projection unit 32 is provided. The pattern projection part 32 is arranged above the conveyance part 20 like the imaging part 30, and projects a projection pattern on the board|substrate G conveyed by the conveyance part 20.

The pattern projection unit 32 is, for example, a coaxial incident illumination type illumination unit that irradiates light onto the optical axis and coaxial of the objective lens included in the imaging unit 30. The pattern projection unit 32 incorporates a mask member on which a projection pattern is drawn, and the mask member is disposed on the optical furnace of the pattern projection unit 32. The projection pattern is projected on the substrate G through the objective lens of the imaging unit 30. Thereby, the projection pattern projected onto the substrate G is reflected in the image picked up by the imaging unit 30.

Here, an example of a projection pattern will be described with reference to FIG. 3. 3 is a diagram showing an example of a projection pattern.

As shown in Fig. 3, the projection pattern includes first to fourth figures P1 to P4 arranged to be spaced apart from each other. The first figure P1 to the fourth figure P4 are arranged, for example, in the vicinity of the center of the four sides of the imaging area (hereinafter referred to as "measurement area R") of the imaging unit 30, respectively. In the example of FIG. 3, the first figure P1 is disposed so as to be close to the center of the side in the negative X-axis direction of the measurement area R, and the first figure P1 is arranged so as to be close to the center of the side in the positive X-axis direction of the measurement area 2 The figure P2 is arranged. In addition, the third figure P3 is arranged close to the center of the side in the positive Y-axis direction of the measurement region R, and the fourth figure P4 is brought close to the center of the side in the negative Y-axis direction of the measurement region R. ) Is placed.

The first figure (P1) to the fourth figure (P4) is, for example, a shape in which a plurality of (here, three) lines of a predetermined width are arranged at a predetermined interval (hereinafter, ``L/S Pattern"). A plurality of lines in the L/S pattern extend along the side of the adjacent measurement region R. Here, an example of the case where the first figure (P1) to the fourth figure (P4) has three lines is shown, but the number of lines included in the first figure (P1) to the fourth figure (P4) is at least 2 It should be more than one.

Returning to Fig. 2, the description of the configuration of the line width measuring device 18 is continued. The moving unit 40 moves the imaging unit 30 in the horizontal direction (X-Y axis direction) or vertical direction (Z direction) with respect to the pattern surface Ga of the substrate G. Specifically, the moving portion 40 includes a guide rail portion 41, a slide portion 42, and a connecting portion 43.

The guide rail portions 41 are disposed on both ends of the conveying portion 20 in the Y-axis direction, respectively, and extend along the X-axis direction. The slide portion 42 is connected to each guide rail portion 41 so as to be slidable (slidable). That is, the slide portion 42 moves linearly along the guide rail portion 41 in the X-axis direction.

The connecting portion 43 is installed above the substrate G, and connects the slide portions 42 to each other. To the connection part 43, the imaging part 30, the camera height measuring part 31, and the pattern projection part 32 are connected to be movable in the Y-axis and Z-axis directions via the attachment plate 44.

Although not shown, the moving part 40 is a driving source for moving the slide part 42 in the X-axis direction with respect to the guide rail part 41, and the imaging part 30, etc. with respect to the connecting part 43 It has a drive source that moves in the direction and the Z-axis direction. As the above-described drive source, for example, an electric motor is used. Thereby, for example, by controlling the driving source of the moving part 40 by the measurement control device 50, the imaging part 30 can be moved with respect to the board|substrate G in three directions of the X, Y, and Z-axis directions.

Next, the measurement control device 50 will be described with reference to FIG. 4. 4 is a block diagram of the measurement control device 50.

The measurement control device 50 is, for example, a computer, and includes a measurement unit 51, a calculation unit 52, a correction unit 53, a mode switching unit 54, and a storage unit 55.

In the storage unit 55, various programs such as a control program for realizing various processes executed by the line width measurement device 18 by control of the measurement control device 50 are stored. In addition, the storage unit 55 stores various data such as processing conditions used in the program. On the other hand, various programs and various data may be stored in a computer-readable computer recording medium (eg, an optical disk such as a hard disk or a DVD, a flexible disk, a semiconductor memory, etc.). In addition, various programs and various data may be stored in other devices, and may be read online through a dedicated line for use.

In the storage unit 55, the pattern shape of the substrate G (hereinafter, referred to as “storage pattern shape”) and positional information of the pattern to be measured on the substrate G are previously stored. For example, in the substrate G, a pattern shape is measured at a plurality of locations.

The measurement control device 50 has an internal memory for storing programs and data, reads the control program stored in the storage unit 55, and executes processing of the read control program. The measurement control device 50 functions as a measurement unit 51, a calculation unit 52, a correction unit 53, and a mode switching unit 54 by operating a control program. On the other hand, the measurement control device 50 includes a transport unit 20, a substrate position detection unit 22, an imaging unit 30, a camera height measurement unit 31, a pattern projection unit 32, a moving unit 40, and the like. Each is connected to enable communication.

(Measurement unit (51))

The measurement unit 51 measures the shape of a projection pattern or an actual pattern based on the image picked up by the imaging unit 30. Specifically, the measurement unit 51 measures the line width of the projection pattern based on the projection pattern imaged by the imaging unit 30. Similarly, the measurement unit 51 measures the line width of the actual pattern based on the actual pattern imaged by the imaging unit 30. Details of the measurement unit 51 will be described later.

(Calculation section (52))

The calculation unit 52 calculates a relative inclination (hereinafter referred to as ``relative angle) between the conveying unit 20 and the image capturing unit 30) based on the projection pattern imaged by the image capturing unit 30. . 5 is a diagram showing an example of a relative angle calculation process performed by the calculation unit 52.

As shown in Fig. 5, the calculation unit 52 first specifies a height position (first focus position h1) of the image pickup unit 30 that focuses on the first figure P1. In addition, the calculation unit 52 determines the height position (second focus position h2) of the imaging unit 30 that focuses on the first graphic P1 and the second graphic P2 lined up along the X-axis direction. To be specified.

Specifically, the calculation unit 52 performs imaging by the imaging unit 30 a plurality of times while changing the height position of the imaging unit 30 using the moving unit 40. Then, the calculation unit 52 determines the height position of the imaging unit 30 with the highest edge strength of the first graphic P1 as the first focus position h1. Similarly, the calculation unit 52 determines the height position of the imaging unit 30 with the highest edge strength of the second graphic P2 as the second focus position h2. On the other hand, the height position of the imaging unit 30 can be measured by the camera height measurement unit 31.

Further, the calculation unit 52 includes a difference between the first and second focus positions h1 and h2 and a distance d between the first and second figures P1 and P2 which are known values. The relative angle θ in the X-axis direction is calculated using an inverse triangular function.

On the other hand, the calculation unit 52 can calculate the relative angle in the Y-axis direction in the same procedure using the third figure P3 and the fourth figure P4 arranged along the Y-axis direction. .

In this way, in the line width measuring device 18 according to the embodiment, the relative angle between the conveying unit 20 and the imaging unit 30 is calculated based on the projection pattern imaged by the imaging unit 30.

Conventionally, in order to adjust the relative angle between the conveyance unit 20 and the image pickup unit 30, a work has been performed in which an operator rises above the line width measuring device 18 and installs a level. However, it cannot be said that such work has a high degree of difficulty and good workability. In addition, when an operator climbs on the line width measuring device 18, the line width measuring device 18 is bent by the operator's weight, and there is a fear that the accuracy of adjustment may be lowered by this bending.

On the other hand, according to the line width measuring device 18 according to the embodiment, the relative angle between the conveying unit 20 and the imaging unit 30 is automatically calculated by the calculation unit 52, as in the prior art. , There is no need for an operator to work on the upper part of the line width measuring device 18. Therefore, compared with the conventional one, it is possible to simplify the adjustment of the relative angle. Further, since the line width measuring device 18 does not warp, the accuracy of the adjustment can be improved. In this way, by improving the accuracy of the adjustment, the measurement accuracy of the actual pattern by the measurement unit 51 can be improved.

On the other hand, the operator manually adjusts the angle of the imaging unit 30 while checking the calculation result of the relative angle by the calculation unit 52 so that the relative angle at all of the plurality of measurement points enters the prescribed value, for example. do. In addition, the present invention is not limited to this, and the line width measurement device 18 may be provided with an adjustment mechanism that adjusts the angle (horizontal degree) of the imaging unit 30. In this case, the line width measurement device 18 can make unnecessary work by an operator by controlling the adjustment mechanism based on the calculation result by the calculation unit 52 to adjust the angle of the imaging unit 30.

Further, according to the calculation unit 52 according to the embodiment, since the relative angle is calculated based on the projection pattern projected on the substrate G, when adjusting the relative angle, the substrate G on which the actual pattern is formed is There is no need to prepare ). Also in this respect, the adjustment operation can be simplified.

On the other hand, the calculation of the relative angle by the above-described calculation unit 52 and the angle adjustment operation of the imaging unit 30 using the calculation result is performed, for example, when the substrate processing system 1 is started.

(The Government of Korea (53))

The correction unit 53 is based on the projection pattern imaged by the imaging unit 30 when measuring the line width of the substrate G as a product substrate after starting the substrate processing system 1, and the measurement unit 51 ) To correct the measurement result of the actual pattern shape.

Here, the contents of the correction processing by the correction unit 53 will be described with reference to FIGS. 6 and 7. 6 is an enlarged view of the periphery of the first graphic P1 among the measurement areas R according to the embodiment. 7 is a diagram showing an example of the first figure P1 imaged in a state where the first figure P1 is not in focus.

First, prior to the description of the correction process, the content of the line width measurement process by the measurement unit 51 will be described with reference to FIG. 6.

6, in the measurement region R, the actual pattern Px formed on the pattern surface Ga of the substrate G, and the projection pattern projected on the pattern surface Ga (here, the first figure (P1)] is transparent. The measurement unit 51 measures the line width A of the actual pattern Px, which is an L/S pattern, based on the image captured by the imaging unit 30.

Specifically, in the vicinity of the actual pattern Px to be measured, there is an eye pattern (not shown) having the same shape as that which can become an eye for the actual pattern Px. The storage unit 55 previously stores the shape of the eye pattern. The shape of the eye surface pattern is used when determining whether or not the actual pattern Px to be measured is included in the image captured by the image pickup unit 30 in the line width measurement processing, which will be described later. .

On the other hand, the shape of the eye pattern is set for each position (also referred to as "measuring point") of the actual pattern Px to be measured, and stored in the storage unit 55. However, for example, in two or more measurement points, when the eye pattern is the same shape, the eye surface pattern may be shared at two or more measurement points.

Further, the above-described positional information is, for example, pixel coordinate information indicating a relative position of a measurement point with respect to an actual pattern that matches the shape of the eye pattern in a captured image. Specifically, an origin is set in the shape of the eye pattern, and the pixel coordinate information includes information on the starting position XY1 and the end position XY2 of the measurement point with respect to the origin.

Specifically, as the viewpoint position XY1, the lower end position of one of the actual pattern Px to be measured (the actual pattern Px on the upper side in Fig. 6) is set, and as the end position XY2, the measurement is performed. The upper end position of the other side of the desired actual pattern Px (lower actual pattern Px in Fig. 6) is set. And the distance between the above-described viewpoint position XY1 and end point position XY2 is measured as "line width A". The measurement of this line width A will be described later. On the other hand, the information of the viewpoint position XY1 and the end point position XY2 described above is displayed by X and Y coordinates in the pixels of the captured image.

On the other hand, the measurement control device 50 feeds back data indicating the line width of the pattern measured in the line width measurement process. In the local exposure apparatus 16, the line width of the measured pattern and the desired line width are compared, and if there is a shift, the shift amount is calculated, and based on the calculated shift amount, the illumination intensity of exposure and the local in the substrate G Correct the exposure position, etc. Thereby, with respect to the substrate G transferred to the local exposure apparatus 16 after correction, local exposure can be performed at the corrected illuminance or the position of the substrate G, and thus the line width of the pattern of the substrate G is desired. Can be corrected with

The measurement unit 51 measures the line widths (B, C) of the projection pattern imaged by the imaging unit 30 in the same procedure. The line width B is the width of the line L included in the projection pattern (here, the first graphic P1). In addition, the line width C is the width of the gap S between two adjacent lines L.

As described above, the actual dimensions of the line widths B and C in the projection pattern are known. However, as shown in FIG. 7, when the first graphic P1 reflected in the image is blurred, the line widths B and C measured by the measurement unit 51 may deviate from the actual dimensions. Specifically, when the first figure P1 is blurred, since the edge of the line L is detected from the inside of the line L, the line width B becomes smaller and the line width C tends to increase. have.

When the projection pattern is blurred, the actual pattern Px is also blurred. Therefore, the correction unit 53 is the ratio (measurement ratio) of the line widths (B, C) in the projection pattern imaged by the imaging unit 30 and the ratio of the line widths (B, C) on the actual dimensions (just Focus ratio), the measurement result of the actual pattern Px is corrected. Here, the value of the line width C when the line width B is 1 is taken as the measurement ratio and the just focus ratio.

For example, while the just focus ratio of the line widths (B, C) is 1 [that is, line width (B): line width (C) = 1:1], the measurement ratio is 1.3 [that is, line width (B): line width (C)) )=1:1.3]. In this case, the correction unit 53 calculates a value 1.3 obtained by dividing the measurement ratio by the just focus ratio as a correction ratio of the measurement result of the actual pattern Px. Then, the correction unit 53 calculates a value obtained by dividing the line width A, which is the measurement result of the actual pattern Px, by the correction ratio 1.3, as the measurement result after correction.

Accordingly, even if the actual pattern Px could not be imaged with just focus, the measurement result at the time of just focus is corrected based on the ratio of the line widths B and C in the projection pattern. Can be estimated. Therefore, it is possible to improve the measurement accuracy of the actual pattern Px. Moreover, since the measurement result at the time of just focus can be estimated by correction, it becomes possible to perform the measurement itself in a relatively rough focus state. Therefore, the time required for focusing can be shortened. In other words, more measurements can be made in the same time.

(Mode switching unit (54))

The mode switching unit 54 switches between a corrected mode in which correction is performed by the correction unit 53 and a no correction mode in which correction is not performed by the correction unit 53. For example, the mode switching unit 54 may switch between a correction present mode and a no correction mode according to an input operation to an input unit (eg, a keyboard) not shown provided in the measurement control device 50. The mode switching unit 54 stores the current mode in the storage unit 55.

The correction present mode includes a conditional correction mode and a full correction mode. The all correction mode is a mode in which correction by the correction unit 53 is performed for all measurement results on one substrate G. On the other hand, the conditional correction mode is a mode in which correction by the correction unit 53 is performed only on a measurement result that satisfies a predetermined condition among a plurality of measurement results on one substrate G. The mode switching unit 54 also switches between the conditional correction mode and the all correction mode.

A predetermined condition in the conditional correction mode is, for example, "a deviation between the measurement ratio and the just focus ratio". That is, in the conditional correction mode, the correction unit 53 determines whether or not the deviation between the measurement ratio and the just focus ratio (e.g., measurement ratio/just focus ratio) is within the threshold value range, and is not within the threshold value range. In the case of determination, the measurement result may be corrected. When the deviation between the measurement ratio and the just focus ratio is not within the threshold value range, there is a high possibility that the actual pattern Px is blurred. In this case, by performing the correction processing by the correction unit 53, the measurement accuracy of the actual pattern Px can be improved.

Further, the predetermined condition in the conditional correction mode may be, for example, a "retry number". The number of retry refers to the number of times of imaging repeated until a desired edge strength is obtained. That is, the correction unit 53 may correct the measurement result when the number of retry is equal to or greater than the predetermined number in the conditional correction mode. When the number of retry is greater than or equal to the predetermined number, line width measurement is performed using an image for which the desired edge intensity is not obtained, that is, an image that is not accurately focused on the actual pattern Px. In this case, by performing the correction processing by the correction unit 53, the measurement accuracy of the actual pattern Px can be improved.

<3. Relative angle calculation processing>

Next, a specific operation of the line width measuring device will be described with reference to FIGS. 8 to 11. First, a relative angle calculation process for calculating a relative angle between the conveyance unit 20 and the imaging unit 30 will be described with reference to FIG. 8. 8 is a flowchart showing the procedure of the relative angle calculation process. On the other hand, each processing shown in FIGS. 8 to 11 is executed under control of the measurement control device 50.

As shown in Fig. 8, the measurement unit 51 controls the operation of the transport unit 20 to transport the substrate G (step S101). As described above, in the relative angle calculation processing according to the embodiment, since the relative angle is calculated using the projection pattern, it is not necessarily required to prepare the substrate G on which the actual pattern Px is formed. Here, it is assumed that the substrate G on which the actual pattern Px is not formed is conveyed, but the substrate G on which the actual pattern Px is formed may be conveyed.

The measurement unit 51 determines whether or not the substrate G is disposed at a predetermined position based on the detection signal output from the substrate position detection unit 22 (step S102).

Subsequently, when the measurement unit 51 determines that the substrate G is not disposed at a predetermined position (step S102, No), the process ends as it is. On the other hand, when it is determined that the substrate G is disposed at a predetermined position (step S102, Yes), the measurement unit 51 stops the operation of the transfer unit 20 to stop the substrate G (step S103).

Subsequently, the measurement unit 51 determines the position of the pattern measurement point on the substrate G, specifically, the measurement point to be measured this time (step S104).

Subsequently, the measurement unit 51 controls the operation of the moving unit 40 so that the imaging unit 30 moves above the determined measurement point (step S105). Specifically, the measurement unit 51 moves the image pickup unit 30 in the horizontal direction, and moves the image pickup unit 30 above the measurement point.

Subsequently, the measurement unit 51 focuses on one of the first graphic P1 to the fourth graphic P4 projected on the measurement area R (step S106). For example, the measurement unit 51 adjusts the height of the imaging unit 30 in the Z-axis direction so that the first graphic P1 is in focus. Then, the measurement unit 51 acquires the height position (focus position) of the imaging unit 30 in step S106 from the camera height measurement unit 31 (step S107), and stores it in the storage unit 55. .

Subsequently, the measurement unit 51 determines whether or not the focus position has been acquired for all of the first graphic P1 to the fourth graphic P4 (step S108). In this process, when there is a figure whose focus position has not yet been acquired (step S108, No), the process shifts to step S106, and the process after step S106 is performed on the figure whose focus position has not yet been acquired.

On the other hand, in step S108, when it is determined that the focus positions have been obtained for all of the first graphic P1 to the fourth graphic P4 (step S108, Yes), the calculation unit 52 determines the difference in the focus position. The relative angle is calculated based on (step S109). For example, the calculation unit 52 includes the transport unit 20 and the imaging unit 30 in the X-axis direction based on the difference between the focus position of the first graphic P1 and the focus position of the second graphic P2. Calculate the relative angle θ of (see Fig. 5). In addition, the calculation unit 52 includes the transport unit 20 and the imaging unit 30 in the Y-axis direction based on the difference between the focus position of the third graphic P3 and the focus position of the fourth graphic P4. Calculate the relative angle of.

Subsequently, the calculation unit 52 determines whether or not the relative angles have been calculated at all the measurement points (step S110). In this process, when there is a measurement point for which the relative angle has not yet been calculated (step S110, No), the calculation unit 52 returns the process to step S104, and after step S104 for the measurement point for which the relative angle has not yet been calculated. Repeat the treatment.

When it is determined in step S110 that the relative angles have been calculated at all the measurement points (step S110, Yes), the calculation unit 52 ends the relative angle calculation process.

<4. Measurement processing>

Next, the measurement processing by the measurement unit 51 will be described with reference to FIG. 9. 9 is a flowchart showing a procedure of measurement processing according to the embodiment.

As shown in Fig. 9, the measurement unit 51 controls the operation of the transport unit 20 to transport the developed substrate G (step S201). Subsequently, the measurement unit 51 determines whether or not the substrate G is disposed at a predetermined position based on the detection signal output from the substrate position detection unit 22 (step S202).

Subsequently, when the measurement unit 51 determines that the substrate G is not disposed at a predetermined position (step S202, No), the process ends as it is. On the other hand, when it is determined that the substrate G is disposed at a predetermined position (step S202, Yes), the measurement unit 51 stops the operation of the transfer unit 20 to stop the substrate G (step S203).

Subsequently, the measurement unit 51 determines the position of the pattern measurement point on the substrate G, specifically, the measurement point to be measured this time (step S204).

Subsequently, the measurement unit 51 controls the operation of the moving unit 40 so that the imaging unit 30 moves above the determined measurement point (step S205). Specifically, the measurement unit 51 moves the image pickup unit 30 in the horizontal direction, and moves the image pickup unit 30 above the measurement point.

Subsequently, the measurement unit 51 adjusts the height of the imaging unit 30 in the Z-axis direction (step S206). Specifically, the measurement unit 51, based on the measurement result of the camera height measurement unit 31, the distance from the lens of the imaging unit 30 to the pattern surface Ga of the substrate G is the imaging unit The operation of the moving unit 40 is controlled so that the work distance of 30 is achieved.

More specifically, the measurement unit 51 uses the camera height measurement unit 31 to measure the height in the Z-axis direction from the imaging unit 30 to the substrate G multiple times, and based on the obtained measurement result. Thus, the amplitude of the vibrating substrate G is calculated. Then, the measurement unit 51 is moved so that the distance from the lens of the imaging unit 30 to the pattern surface Ga of the substrate G becomes the work distance of the imaging unit 30 according to the calculated median value of the amplitude. Controls the operation of the unit 40.

Accordingly, even when the substrate G is vibrating, it is possible to easily capture an image in focus in the processing described later. Incidentally, in the above, the median value of the amplitude was used, but the present invention is not limited thereto, and may be, for example, an arithmetic mean or mode.

Subsequently, the measurement unit 51 determines whether or not the number of times the pattern is imaged by the imaging unit 30 is equal to or greater than the prescribed number of times (step S207). The prescribed number of times is set to an integer of 2 or more, for example.

In step S207, when it is determined that the number of times of imaging is less than the prescribed number of times (step S207, No), the measurement unit 51 performs imaging by the imaging unit 30 (step S208).

Subsequently, the measurement unit 51 performs a pattern search process (step S209). In the pattern search process, for example, a correlation value between the pattern shape (hereinafter referred to as "image pattern shape") included in the image information and the eye pattern stored in the storage unit 55 is calculated. The correlation value is a value indicating the similarity between the image pattern shape and the eye pattern.

Subsequently, the measurement unit 51 determines whether or not the calculated correlation value is equal to or greater than a predetermined correlation value (step S210). When the correlation value is less than a predetermined correlation value, the measurement unit 51 determines that the image information does not contain a pattern that matches the eye pattern and does not contain the actual pattern Px to be measured as a result. do. Further, when the correlation value is equal to or greater than a predetermined correlation value, the measurement unit 51 determines that the image information includes a pattern that matches the eye pattern and includes the actual pattern Px to be measured.

That is, the pattern search process is a process of determining whether or not the position of the imaging unit 30 is shifted from the actual pattern Px (measurement point) to be measured. Therefore, when the correlation value is less than a predetermined correlation value (step S210, No), the measurement unit 51 determines that the image pickup unit 30 is at a different position from the measurement point, and determines the position of the image pickup unit 30. Adjust (step S211).

The measurement unit 51 moves, for example, the imaging unit 30 in the horizontal direction. On the other hand, the measurement unit 51 may lower the magnification of the lens of the imaging unit 30 to enlarge the camera field of view, and move the imaging unit 30 to the measurement point based on image information from the enlarged camera field of view. . The measurement unit 51 adjusts the position of the imaging unit 30 and then executes the imaging process again (step S208).

In this way, when the correlation value is less than the predetermined correlation value, the imaging unit 30 is made to perform the imaging of the pattern of the substrate G again, so that the measurement unit 51 is the actual pattern Px to be measured. It is possible to prevent incorrectly measuring line widths other than the line width A of.

On the other hand, when the correlation value is greater than or equal to a predetermined correlation value (step S210, Yes), the measurement unit 51 calculates the edge strength of the actual pattern Px based on the image information, and the calculated edge strength is a predetermined edge It is determined whether or not the strength is greater than or equal to the intensity (step S212). The edge intensity means the degree of change in the shade of the boundary line (contour) in the imaged pattern, and means that the shade becomes clear, that is, the focus is achieved as the edge strength increases.

When the edge intensity is less than the predetermined edge intensity (step S212, No), the measurement unit 51 returns to step S207 because the image captured by the imaging unit 30 is out of focus. And, if the number of imaging is still less than the specified number, in other words, when the number of imaging has not reached the specified number, the measurement unit 51 performs the imaging of the substrate G again in step S208, and step S209 The subsequent processing is executed again.

When the edge strength is greater than or equal to the predetermined edge strength (step S212, Yes), the picked image is in focus, and thus the start position (XY1) and the end point position (XY2) of the measurement point are used using the picked image. ) Is calculated (step S213). Then, the measuring unit 51 measures the distance between the starting point position XY1 and the end point position XY2 calculated in step S213 as the line width A of the actual pattern Px at the measuring point (step S214. ).

On the other hand, the measurement unit 51, even when the number of times of image pickup in step S207 is equal to or greater than the prescribed number of times (step S207, Yes), the process shifts to step S213, ) Is calculated. At this time, the measurement unit 51 calculates the viewpoint position XY1 and the end point position XY2 using, for example, an image that is less than the specified edge intensity, but has the highest edge intensity among imaging performed a plurality of times.

Subsequently, the correction unit 53 performs a correction process for correcting the measurement result of the measurement unit 51 (step S215). The contents of the correction processing will be described later.

Subsequently, the measurement unit 51 determines whether or not the measurement of the plurality of measurement points has been completed (step S216). When it is determined that the measurement of the plurality of measurement points has not been completed (steps S216, No), the measurement unit 51 returns to step S204 to determine the position of the other measurement points, and the line width of steps S205 to S214 described above. Take measurements. On the other hand, when the measurement of a plurality of measurement points is finished (step S216, Yes), the measurement unit 51 ends this process. That is, the line width measurement process for one substrate G is ended.

<5. Correction processing>

Next, the correction processing by the correction unit 53 will be described with reference to FIGS. 10 and 11. 10 is a flowchart showing an example of a procedure of correction processing according to the embodiment. 11 is a flowchart showing another example of the procedure of correction processing according to the embodiment. On the other hand, the processing of steps S401, S402, S404, and S405 shown in FIG. 11 is the same as the processing of steps S301, S302, S304, and S305 shown in FIG.

As shown in Fig. 10, the correction unit 53 determines whether or not the current mode is a correction present mode (step S301), and when the current mode is not a correction present mode (step S301, No), The process ends as it is without correcting the measurement result.

In step S301, when the current mode is a correction mode (step S301, Yes), the correction unit 53 determines whether or not it is the all correction mode (step S302).

In step S302, when it is determined that it is the all correction mode (step S302, Yes), the correction unit 53 calculates the correction ratio of the measurement result based on the deviation between the measurement ratio of the line widths B and C and the just focus ratio. Calculation (step S304). Then, the correction unit 53 corrects the measurement result of the actual pattern Px using the calculated correction ratio (step S305). That is, the correction unit 53 calculates a value obtained by dividing the line width A, which is the measurement result of the actual pattern Px, by the correction ratio, as the measurement result after correction.

In step S302, when not in the all correction mode (step S302, No), that is, in the conditional correction mode, the correction unit 53 determines whether or not the deviation between the measurement ratio and the just focus ratio is within the threshold value range. It is determined (step S303).

In step S303, when it is determined that the deviation between the measurement ratio and the just focus ratio is within the threshold value range (step S303, Yes), the correction unit 53 does not correct the measurement result and ends the process as it is.

On the other hand, when it is determined that the deviation of the measurement ratio and the just focus ratio is not within the threshold value range (step S303, No), the correction unit 53 calculates the correction ratio (step S304), and uses the calculated correction ratio. The measurement result is corrected (step S305).

On the other hand, the predetermined condition in the conditional correction mode may be a "retry number". In this case, as shown in Fig. 11, when the current mode is a correction present mode (step S401, Yes) and not all correction mode (step S402, No), the correction unit 53 is It is determined whether or not the number of times is less than the threshold value (step S403).

If it is determined in step S403 that the number of retry is less than the specified number (step S403, Yes), the correction unit 53 does not correct the measurement result and ends the process as it is.

On the other hand, when it is determined that the number of retry has reached the prescribed number (step S403, No), the correction unit 53 calculates a correction ratio (step S404), and corrects the measurement result using the calculated correction ratio. (Step S405).

<6. Effect>

As described above, the pattern measuring device (as an example, the line width measuring device 18) according to the embodiment includes a conveying unit (as an example, a conveying unit 20), and a pattern projection unit (as an example, a pattern projection unit). (32)], an imaging unit (as an example, an imaging unit 30), and a measurement unit (as an example, a measurement unit 51). The transport unit transports the substrate (as an example, the substrate G). The pattern projection unit is disposed above the transport unit and projects the projection pattern onto the substrate transported by the transport unit. The imaging unit is disposed above the transport unit and captures a projection pattern projected onto the substrate or an actual pattern formed on the substrate. The measurement unit measures the shape of a projection pattern or an actual pattern based on the image picked up by the imaging unit. Therefore, according to the pattern measuring apparatus according to the embodiment, the pattern shape can be accurately measured.

The pattern measuring device according to the embodiment may further include a calculation unit (as an example, a calculation unit 52). The calculation unit 52 calculates a relative inclination of the conveyance unit and the image pickup unit based on the projection pattern imaged by the imaging unit.

Specifically, the pattern measuring apparatus according to the embodiment may further include a moving unit (for example, the moving unit 40) that moves the imaging unit along the vertical direction. Further, the projection pattern may include a first graphic (for example, a first graphic P1) and a second graphic (for example, a second graphic P2) arranged spaced apart from each other. In this case, the calculation unit includes the height of the image pickup unit that focuses on the first figure (as an example, the first focus position h1) and the height of the image pickup unit that focuses on the second figure (as an example, the second focus position h2). )], the relative inclination of the conveying unit and the imaging unit may be calculated.

According to the pattern measuring device according to the embodiment, as in the prior art, there is no need for an operator to work on the upper part of the pattern measuring device. Therefore, compared with the conventional one, it is possible to simplify the adjustment of the relative angle. In addition, since warping of the pattern measuring device due to an operator's rise does not occur, the precision of adjustment can be improved. In this way, by improving the accuracy of the adjustment, it is possible to improve the measurement accuracy of the actual pattern.

The pattern measuring apparatus according to the embodiment may further include a correction unit (for example, a correction unit 53) for correcting the measurement result by the measurement unit. Further, the imaging unit captures an image of a measurement area (as an example, a measurement area R) on the substrate including the projection pattern and the actual pattern, and the measurement unit is based on the actual pattern imaged by the imaging unit, and the shape of the actual pattern You may measure In this case, the correction unit may correct the measurement result of the shape of the actual pattern by the measurement unit based on the projection pattern imaged by the imaging unit.

Thereby, even if an actual pattern cannot be imaged with just focus, the measurement result at the time of just focus can be estimated by correcting the measurement result based on the projection pattern imaged by the imaging unit. Therefore, it is possible to improve the measurement accuracy of the actual pattern.

The projection pattern is a figure (as an example, a first figure (P1) to a fourth figure) in which a plurality of lines of a predetermined width (as an example, a line L) are arranged at a predetermined interval [as an example, a gap S]. (P4)]. In this case, the correction unit includes a measurement ratio, which is a ratio of the line width in the projection pattern imaged by the image pickup unit (line width B as an example) and the space between the lines [line width C as an example], and in advance The correction ratio of the measurement result may be calculated based on the just focus ratio which is the ratio of the determined width and the predetermined interval. Thereby, the measurement result at the time of just focus can be estimated by correcting the measurement result using the calculated correction ratio.

The correction unit may determine whether or not the measurement ratio is within the threshold value range, and when determining that the measurement ratio is not within the threshold value range, may correct the measurement result. When the deviation between the measurement ratio and the just focus ratio is not within the threshold range, there is a high possibility that the actual pattern is blurred. In this case, by performing the correction processing by the correction unit, the measurement accuracy of the actual pattern can be improved.

The pattern measuring apparatus according to the embodiment may further include a moving part that moves the imaging part along the vertical direction. In addition, when the edge intensity of the imaged real pattern is less than a predetermined value, the imaging unit may image the measurement area again after changing the height position using the moving unit. In addition, when the number of images of the same measurement area by the image pickup unit (for example, the number of retry) reaches a predetermined number, the measurement unit is based on the actual pattern image in which the edge intensity is less than the predetermined value. You may measure the shape of the pattern. In this case, the correction unit measures the shape of the actual pattern measured based on the image of the actual pattern whose edge intensity is less than the predetermined value when the number of images of the same measurement area by the image pickup unit reaches a predetermined number. You may correct the results. When the number of retry is equal to or greater than the predetermined number, line width measurement is performed using an image in which the desired edge strength is not obtained, that is, an image that is not accurately focused on an actual pattern. In this case, by performing the correction processing by the correction unit, the measurement accuracy of the actual pattern can be improved.

The pattern measuring apparatus according to the embodiment includes a mode switching unit (as an example, a mode switching unit 54) for switching between a mode with correction for performing correction by a correction unit and a mode without correction for performing correction by the correction unit. You may have more. Thereby, for example, the user of the pattern measuring device can select whether or not to correct the measurement result.

The with correction mode may include a conditional correction mode in which correction by a correction unit is performed on a measurement result that satisfies a predetermined condition, and a total correction mode in which correction by a correction unit is performed on all measurement results. In this case, the mode switching unit may switch between the conditional correction mode and the entire correction mode.

In addition, the tilt calculation method in the pattern measurement device according to the embodiment includes a transfer process, a pattern projection process, an imaging process, a calculation process, and a transfer process, and are arranged above the transfer section and the transfer section to transfer the substrate. The substrate and the actual pattern are provided with an imaging unit for imaging the substrate conveyed by the conveying unit, and using the conveying unit of the pattern measuring device to measure the shape of the actual pattern formed on the substrate based on the image captured by the imaging unit. The target substrate (as an example, the substrate G), which is one of the substrates not formed, is transported. The pattern projection process projects a projection pattern on the target substrate conveyed in a conveyance process. In the imaging process, a projection pattern projected on a substrate is imaged using an imaging unit. The calculation process calculates the relative inclination (as an example, a relative angle) of a conveyance part and an imaging part based on the image picked up in an imaging process.

According to the inclination calculation method in the pattern measuring device according to the embodiment, as in the prior art, it is not necessary for an operator to rise above the pattern measuring device to work. Therefore, compared with the conventional one, it is possible to simplify the adjustment of the relative angle. In addition, since warping of the pattern measuring device due to an operator's rise does not occur, the precision of adjustment can be improved. In this way, by improving the accuracy of the adjustment, it is possible to improve the measurement accuracy of the actual pattern.

In addition, the pattern measurement method according to the embodiment includes a conveyance process, a pattern projection process, an imaging process, a measurement process, and a correction process. The conveyance process conveys a board|substrate using a conveyance part. In the pattern projection process, a projection pattern is projected onto the substrate conveyed by the conveying unit. In the imaging process, a measurement area on a substrate including a projection pattern projected onto the substrate and an actual pattern formed on the substrate is captured using an imaging unit disposed above the transport unit. The measurement process measures the shape of the actual pattern based on the actual pattern imaged by the imaging unit. The correction process corrects the measurement result of the actual pattern in the measurement process based on the projection pattern imaged by the imaging unit.

Thereby, even if an actual pattern cannot be imaged with just focus, the measurement result at the time of just focus can be estimated by correcting the measurement result based on the projection pattern imaged by the imaging unit. Therefore, it is possible to improve the measurement accuracy of the actual pattern.

On the other hand, it should be thought that embodiment disclosed this time is an illustration and restrictive in all points. Actually, the above-described embodiment can be implemented in various forms. In addition, the above-described embodiment may be omitted, substituted, or changed in various forms without departing from the scope of the appended claims and the spirit thereof.

Claims (11)

As a pattern measuring device,
A transport unit that transports the substrate,
A pattern projection unit disposed above the transport unit and projecting a projection pattern onto the substrate transported by the transport unit;
An imaging unit disposed above the transfer unit and configured to capture the projection pattern projected onto the substrate or an actual pattern formed on the substrate;
Measurement unit for measuring the shape of the projection pattern or the actual pattern based on the image captured by the imaging unit
Containing, pattern measuring device. The method of claim 1,
A calculation unit that calculates a relative inclination of the transport unit and the image pickup unit based on the projection pattern imaged by the image pickup unit
Further comprising a, pattern measuring device. The method of claim 2,
A moving part that moves the image pickup part along a vertical direction
Including more,
The projection pattern includes a first figure and a second figure arranged to be spaced apart from each other,
The calculation unit,
A pattern measuring device that calculates a relative inclination of the conveying unit and the imaging unit based on a difference between a height of the imaging unit in focus on the first graphic and a height of the imaging unit in focus on the second graphic . The method of claim 1,
Correction unit for correcting the measurement result by the measurement unit
Including more,
The imaging unit,
Taking an image of a measurement area on the substrate including the projection pattern and the actual pattern,
The measuring unit,
Based on the actual pattern imaged by the imaging unit, the shape of the actual pattern is measured,
The correction unit,
A pattern measuring device for correcting a measurement result of the shape of the actual pattern by the measuring unit based on the projection pattern imaged by the imaging unit. The method of claim 4,
The projection pattern has a figure in which a plurality of lines of a predetermined width are arranged at predetermined intervals,
The correction unit,
The measurement is based on a measurement ratio that is a ratio of the width of the line and the spacing between the lines in the projection pattern imaged by the imaging unit, and a just focus ratio that is a ratio of the predetermined width and the predetermined interval The pattern measuring device which calculates the correction ratio of a result. The method of claim 5,
The correction unit,
A pattern measuring apparatus, wherein it is determined whether or not the measurement ratio is within a threshold value range, and when it is determined that the measurement ratio is not within the threshold value range, correction of the measurement result is performed. The method according to claim 4 or 5,
A moving part that moves the image pickup part along a vertical direction
Including more,
The imaging unit,
When the edge strength of the imaged real pattern is less than a predetermined value, after changing the height position using the moving part, the measurement area is again imaged,
The measuring unit,
When the number of images of the same measurement area by the imaging unit reaches a predetermined number, the shape of the actual pattern is measured based on the image of the actual pattern in which the edge intensity is less than the predetermined value,
The correction unit,
Measurement of the shape of the actual pattern measured on the basis of the image of the actual pattern in which the edge intensity is less than the predetermined value when the number of images of the same measurement area by the imaging unit reaches a predetermined number To correct the result, pattern measuring device. The method of claim 4,
A mode switching unit for switching between a mode with correction for performing correction by the correction unit and a mode without correction for performing correction by the correction unit
Further comprising a, pattern measuring device. The method of claim 8,
The correction with mode,
A conditional correction mode in which correction by the correction unit is performed on the measurement result that satisfies a predetermined condition, and a total correction mode in which correction by the correction unit is performed on all the measurement results,
The mode switching unit,
To switch the conditional correction mode and the entire correction mode, pattern measuring device. As a tilt calculation method in a pattern measuring device,
An actual pattern formed on the substrate based on an image captured by the image pickup unit, comprising a transport unit for transporting the substrate, and an image capturing unit disposed above the transport unit and for imaging the substrate transported by the transport unit A transfer step of transferring a target substrate, which is any one of the substrate and the substrate on which the actual pattern is not formed, by using the transfer part of the pattern measurement device for measuring the shape of,
A pattern projection step of projecting a projection pattern onto the target substrate conveyed in the transport step,
An imaging process of imaging the projection pattern projected on the substrate using the imaging unit,
A calculation process of calculating a relative inclination of the conveying unit and the imaging unit based on the image captured in the imaging process
The inclination calculation method in the pattern measuring device containing. As a pattern measurement method,
A transfer step of transferring the substrate using a transfer unit,
A pattern projection step of projecting a projection pattern onto the substrate carried by the transfer unit,
An imaging step of imaging a measurement area on the substrate including the projection pattern projected onto the substrate and an actual pattern formed on the substrate using an image pickup unit disposed above the transfer unit;
A measurement process of measuring the shape of the actual pattern based on the actual pattern imaged by the imaging unit,
A correction step of correcting a measurement result of the actual pattern in the measuring step based on the projection pattern imaged by the imaging unit
Containing, pattern measurement method.

Images