JP2016205958A - Method for correcting movable head position of x-y substrate inspection device, and x-y substrate inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for correcting the movable head position of an X-Y substrate inspection device for correcting displacement in the amount of movement of a ball screw due to change in temperature of the ball screw in X-Y substrate inspection devices using a ball screw, and also to provide an X-Y substrate inspection device.SOLUTION: Reference mark sequences 22 and 23 with known coordinate positions are installed in the X axis direction and the Y axis direction. An X-axis drive unit 10 and a Y-axis drive unit are driven, and a movable head 17 is moved to reference mark positions in the X axis direction and the Y axis direction. The reference mark sequences 22 and 23 are photographed at the positions after movement, the amount of displacement of the positions after movement from the reference mark sequences 22 and 23 is detected, and command values given to the X-axis drive unit 10 and the Y-axis drive unit are corrected on the basis of the detected amount of displacement.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a movable head position correction method for an XY substrate inspection apparatus and an XY substrate inspection apparatus.

  As an inspection apparatus for a printed wiring board or the like, an XY board inspection apparatus that performs inspection by bringing a movable probe into contact with a substrate to be inspected is known. This XY substrate inspection device inspects a probe at a target position by moving a movable head mounted with a probe called a flying probe, which is brought into contact with a substrate to be inspected, on an XY plane (secondary plane). An inspection is performed by contacting the target substrate. An XY orthogonal two-axis drive mechanism for driving the movable head on the XY plane includes a Y-axis drive unit for moving the movable head with a ball screw, and the Y-axis drive unit in the X-axis direction orthogonal to the Y-axis. An X-axis drive unit that is moved by a ball screw is provided. Here, a unit that moves the movable head in the ball screw direction with a ball screw is referred to as a Y-axis drive unit, and a mechanism that moves the Y-axis drive unit with a ball screw in a direction orthogonal to the Y axis is referred to as an X-axis drive unit.

  This will be described with reference to the drawings. FIG. 6 is a simplified representation of the plane of the XY orthogonal two-axis drive mechanism of the XY substrate inspection apparatus for explanation. The XY orthogonal two-axis drive mechanism includes an X-axis drive unit 10 that drives in the long X-axis direction and a Y-axis drive unit 14 that drives in the short Y-axis direction in the drawing. The X-axis drive unit 10 includes an X-axis ball screw 11 installed at one end in the Y-axis direction (one side of X) and an X-axis linear installed at the other end in the Y-axis direction (the other side of X). A guide 12 is provided. The Y-axis drive unit 14 is provided so as to be hung between the X-axis ball screw 11 and the X-axis linear guide 12, and the Y-axis ball screw 15 moves the movable head 17 on which the probe 18 is mounted in the Y-axis direction. . The X-axis drive unit 10 moves the Y-axis drive unit 14 in the X-axis direction.

The X-axis ball screw 11 and the Y-axis ball screw 15 are driven by a servo motor under the control of a control device (not shown) to move the movable head 17 to arbitrary coordinate positions (Xi, Yi) in the X-axis direction and the Y-axis direction. The probe 18 can be lowered at a designated position and brought into contact with the substrate to be inspected.
The movable head 17 is provided with a camera 19, which can determine whether the probe 18 has accurately reached the position of the measurement target.

JP 2000-055971 A

  By driving the ball screw in both the X-axis drive unit and the Y-axis drive unit, the temperature of the ball screw rises due to frictional heat. Due to the temperature change of the ball screw, the pitch of the ball screw is shifted, and a shift occurs between the control command value for instructing the target coordinates of the movable head and the actual movement amount. This will be described with reference to the drawings.

  As shown in FIG. 7A, when the movable head 17 is moved by x (μm), if the theoretical pitch of the ball screw is p (μm), the ball screw is rotated by A = x / p. For example, when the temperature rises, the pitch of the ball screw increases due to the effect of thermal expansion. Therefore, as shown in FIG. 7B, even if it is rotated A, the amount of movement does not become x, and x + Δx and Δx depending on the temperature. It will increase by a minute.

  Since ball screws are required to be rigid, they are mostly made of steel. Since steel is a material having a rather large thermal expansion coefficient, there is a problem that a deviation (error) is likely to occur in the position control of the movable head due to an increase in temperature.

The following two methods can be considered as a method of correcting the shift of the movement amount due to such a temperature change. The first is a method of controlling movement while providing a precise scale with little temperature change such as a linear scale, measuring the actual movement amount with this scale, and correcting the shift of the movement amount due to temperature change. . If the movement control is performed while measuring the movement amount each time on a scale with a small temperature change, there is a problem that the movement control takes time and inspection time. In addition, an expensive and precise device such as a linear scale is required, which increases the cost of the apparatus.
Although the above-mentioned patent document 1 does not measure a deviation amount due to a temperature change, since an actual movement amount is detected using a linear scale, a deviation caused by a temperature change is also measured to correct the control. be able to.

  Further, as a second method, a method of measuring the amount of change in temperature, calculating a correction value of the movement amount from the thermal expansion coefficient of the ball screw, and reflecting it in a command value for a servo motor that rotates the ball screw can be considered. . In this method, since there is an error in the temperature measured depending on the place where the temperature is measured, the correction amount error also increases. For example, the temperature differs between the end portion and the central portion of the ball screw, so that the amount of deviation due to temperature change differs depending on which portion of the ball screw.

  The present invention solves the above-described problems, and detects a shift of a target position moved in advance by a temperature change of a ball screw of an X-axis drive unit and a Y-axis drive unit using a camera mounted on a movable head. Then, it aims at providing the method and apparatus which correct | amend the position shift which arises by a temperature change at a test process.

  In order to solve the above-described problem, one aspect of the present invention includes an XY orthogonal two-axis drive mechanism that enables a movable head mounted with a probe to move forward and backward on an XY plane. The axis drive mechanism includes an orthogonal X-axis drive unit, a Y-axis drive unit, and a control device that controls the drive of the X-axis drive unit and the Y-axis drive unit. The X-axis drive unit includes the Y-axis drive unit. The X-axis ball screw provided on one side in the X-axis direction and a linear guide provided on at least the other side move the X-axis direction, and the Y-axis drive unit moves the movable head in the Y-axis direction using the Y-axis ball screw. A movable head position correction method for an XY substrate inspection apparatus, wherein reference marks whose coordinate values are known are set in the X-axis direction and the Y-axis direction, respectively, Moving the target position, imaging a reference mark of the X-axis direction and the Y-axis direction movement position, characterized in that it comprises a step of detecting a shift amount from the reference mark of the moved position.

  It is preferable that the substrate inspection process includes a step of correcting command values given to the X-axis drive unit and the Y-axis drive unit based on the detected deviation amount. The reference mark is preferably printed or engraved on a member made of a material having a small thermal expansion coefficient at a period that falls within the field of view of the camera, and the detecting step is preferably executed periodically.

  Another aspect of the present invention includes an XY orthogonal biaxial drive mechanism that enables a movable head mounted with a probe to move forward and backward on an XY plane, and the XY orthogonal biaxial drive mechanism is orthogonal. An X-axis drive unit, a Y-axis drive unit, and a control device that controls driving of the X-axis drive unit and the Y-axis drive unit are provided. The X-axis drive unit moves the Y-axis drive unit to one side in the X-axis direction. An X-Y board inspection apparatus in which the Y-axis drive unit moves the movable head in the Y-axis direction by the Y-axis ball screw, and the Y-axis drive unit moves the X-axis direction by the X-axis ball screw provided in the X-axis and the linear guide provided at least on the other side. A reference mark having a known coordinate value is provided in each of the X-axis direction and the Y-axis direction, and the control device moves the movable head to the target position of the reference mark in the X-axis direction and the Y-axis direction. Imaging a reference mark of the X-axis direction and the Y-axis direction position, and further comprising a means for detecting a deviation amount from the reference mark of the moved position.

  Note that the control device preferably includes means for correcting command values to be given to the X-axis drive unit and the Y-axis drive unit based on the detected deviation amount. The reference mark is preferably printed or engraved on a member made of a material having a small coefficient of thermal expansion at a cycle of a distance that falls within the field of view of the camera, and the control device includes means for periodically detecting the shift amount. It is preferable.

  According to the present invention, it is possible to correct the displacement of the movable head caused by the temperature change of the ball screw. Further, the inspection time is not lengthened, and the apparatus cost can be reduced.

It is a figure explaining the control structure of the XY orthogonal two-axis drive mechanism of the XY board | substrate inspection apparatus of this invention. It is a top view explaining the structure in the XY plane of the XY orthogonal biaxial drive mechanism of this invention. It is a figure explaining the operation | movement which image | photographs a reference mark with the camera in this invention, and calculates | requires the movement amount. It is a flowchart explaining the operation | movement which calculates | requires the correction amount by the temperature change of the XY board | substrate inspection apparatus in this invention. It is a flowchart explaining the operation | movement which correct | amends a target coordinate value at the time of the test | inspection of the XY board | substrate inspection apparatus in this invention. It is the figure which represented the plane of the XY orthogonal biaxial drive mechanism simply. It is a figure explaining the shift | offset | difference which arises with the temperature change of the ball screw of the conventional XY board | substrate inspection apparatus.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram for explaining a drive control configuration of an XY orthogonal two-axis drive mechanism of an XY substrate inspection apparatus according to an embodiment of the present invention, and FIG. 2 is an XY orthogonal two-axis drive mechanism. It is a top view which shows the structure in XY plane.

  The XY orthogonal two-axis drive mechanism includes an X-axis drive unit 10 that drives in the X-axis direction that is long in the drawing, and a Y-axis drive unit 14 that drives in the Y-axis direction that is orthogonal to the X-axis and short in the drawing. And a control device 20. The X-axis drive unit 10 includes an X-axis ball screw 11 and an X-axis servo motor 13 that rotationally drives the X-axis ball screw 11. The Y-axis drive unit 14 includes a Y-axis ball screw 15 and a Y-axis servo motor 16 that rotationally drives the Y-axis ball screw. The Y-axis drive unit 14 is equipped with a movable head 17, and the movable head 17 includes a probe 18 and a camera 19.

  Both the X-axis servo motor 13 and the Y-axis servo motor 16 are driven under the control of the control device 20, and the X-axis drive unit 10 moves the Y-axis drive unit 14 in the X-axis direction, and the Y-axis drive unit 14. Moves the movable head 17 in the Y-axis direction, and moves the movable head 17 to the XY coordinate position indicated by the control device 20.

  In FIG. 2, the X-axis drive unit 10 has only one X-axis linear guide 12 represented on the other side of the X-axis ball screw 11, but a linear guide is provided along the X-axis ball screw 11. As a result, the operation of the X-axis drive unit 10 is not changed. In the Y-axis drive unit 14, a Y-axis ball screw 15 is shown. However, the positioning drive device using the ball screw includes one or two linear guides, but is not shown for the sake of simplicity. did.

  The movable head 17 is provided with a probe 18 that can move in a direction orthogonal to the XY plane (Z direction). During substrate inspection, the control device 20 controls the substrate to be inspected at a predetermined position (inspection point). Can be in contact with the substrate to inspect the substrate. In addition, a camera 19 is attached to the movable head 17, and at the time of substrate inspection, an image of a position where the probe 18 has arrived is acquired, and it is determined whether the probe 18 has moved to the designated position on the substrate to be inspected. can do.

In the present embodiment, the difference between the command value (target position) and the actual moved position when the temperature of the X-axis ball screw 11 of the X-axis drive unit 10 and the X-axis ball screw 15 of the Y-axis drive unit 14 is changed. For detection, an X axis in which reference marks whose coordinate positions are known are arranged on one side in the X axis direction of the stage 21 on which the substrate to be inspected on the XY plane is mounted, that is, inside the X axis linear guide 12. A reference mark row 22 is arranged, and a Y-axis reference mark row 23 is arranged at the end of the stage 21 in the X-axis direction.
Here, the reference mark row refers to a reference mark arranged in a line, and each mark is referred to as a reference mark.

  The X-axis reference mark row 22 and the Y-axis reference mark row 23 are obtained by periodically printing or engraving marks for image recognition. The medium on which the reference mark is printed or engraved is preferably made of a material having a small coefficient of thermal expansion and no deterioration in accuracy due to environmental changes, such as quartz glass. The X-axis reference mark row 22 and the Y-axis reference mark row 23 may be printed or stamped directly on the end of the stage 21 on which the substrate is mounted, and are attached to the stage 21 with precise alignment. It may be a thing. Further, since the reference mark may be captured and recognized by the camera 19 of the movable head 17 separately from the stage 21, it may be provided separately from the stage 21.

  The reference marks in the X-axis reference mark row 22 and the Y-axis reference mark row 23 are preferably marks for image processing that are captured by the camera 19 and that can calculate the distance between the mark and the center of the camera by image processing. Such a mark may be a circle or a cross. The reference marks are periodically arranged. When the field of view (view angle) of the camera 19 is about 3 mm, for example, printing and marking are performed at intervals of 3 mm. This is because the distance from the center (optical axis) of the camera can be calculated by image processing if a reference mark enters the field of view of the camera 19. As described above, the reference marks provided in the X-axis reference mark row 22 and the Y-axis reference mark row 23 do not need a scale such as a linear scale used in a precision machine tool or the like. Although the accuracy of the reference mark itself depends on the resolution of the camera 19, it may be about the drive control accuracy of the XY orthogonal biaxial drive mechanism and does not require the accuracy required for the linear scale.

  The X-axis reference mark row 22 and the Y-axis reference mark row 23 are provided to be aligned in order to make the coordinates of each reference mark known. Since this reference mark only needs to be in the field of view of the camera when the movable head moves to the commanded target position, the reference mark itself does not need to display a numerical value indicating the coordinate position like a scale, and is the same It may be a periodic arrangement of marks. Further, since the coordinate value of each reference mark is known, if the control device indicates the coordinate value of the reference mark as a command value, the movable head 17 reaches the position of the commanded coordinate value of the reference mark. If there is no deviation, the reference mark is positioned at the center of the field of view of the camera 19.

Next, with reference to FIG. 3, FIG. 4, and FIG. 5, the operation of detecting the amount of deviation caused by the temperature change of the ball screw and correcting the position will be described.
FIG. 3 is a diagram for explaining the operation of moving the movable head 17 in the direction of the arrow with a ball screw and taking an image of the reference mark with the camera 19 and obtaining the amount of deviation between the reference mark and the moved target position (theoretical coordinates). FIG. 4 is a flowchart for explaining an operation for detecting a deviation amount, and FIG. 5 is a flowchart for explaining an operation for correcting a command value at the time of substrate inspection based on the detected deviation amount.

  First, prior to the substrate inspection, a deviation amount between the target position and the reference mark due to a temperature change occurring in the X-axis direction and the Y-axis direction is detected.

  Since the deviation is caused by temperature change, particularly thermal expansion of the ball screw due to frictional heat, the deviation amount is detected when the temperature rise is saturated to some extent. For example, assuming that the temperature of the ball screw is in the room temperature state before the start of the inspection, a deviation amount caused by the temperature rise is detected at a stage where the temperature rises and becomes almost saturated, for example, a stage where the temperature rises by about 20 ° C. In a state where the temperature is rising, the deviation amount is also changed, and the value to be corrected to the command value is also considered to be changed. Therefore, it is preferable to detect when the temperature change is saturated to some extent. Further, since the temperature change changes depending on the operation state, the deviation amount is periodically taken again. Also, since the temperature is considered to change slightly depending on the position of the ball screw, the amount of deviation when moving to a plurality of regions is detected by dividing the X-axis direction and the Y-axis direction into a plurality of regions. A deviation amount detected differently depending on the movement position is stored by creating a table for each item. The values stored in this table are read out during the movement control of the movable head at the time of inspection to correct the command value (target coordinate value).

  First, it is determined whether a condition for detecting a deviation amount due to a temperature change is satisfied (step S1). For example, whether a predetermined time has elapsed since the start of operation, a predetermined time has elapsed since the previous detection, a predetermined distance has been moved, a predetermined number of points have been inspected, or the temperature of the ball screw has reached a predetermined temperature, etc. In this case, the operation shifts to a shift amount detection operation.

When the shift amount detection operation condition is satisfied, the shift amount in the X-axis drive unit 10 is detected. The detection of the amount of deviation may be detected from the amount of deviation of either the X axis or the Y axis, but here it will be described by detecting the amount of deviation in the order of the X axis and the Y axis. The X-axis drive unit 10 is driven, the movable head 17 is adjusted to the origin position of the X-axis, and the movable head 17 is moved to the theoretical coordinates of the X-axis reference mark (step S2). The origin position is normally provided at the end of the stage 21 and is a position that becomes the base point of the operation range (XY) of the movable head. First, after moving the movable head 17 to the origin, the movable head 17 is moved to an arbitrary target coordinate for detecting a shift amount due to a temperature change, actually, to a coordinate position of a target reference mark in the X-axis reference mark row 22. For example, at this time, if the Y coordinate on the X-axis ball screw 11 side is set to “0” and the movable head 17 is moved toward the X-axis reference mark row 22 side, the Y-axis drive unit 14 is moved in the X-axis direction. A command value of (X _i , Y ₀ ) is given as the target coordinate position.

  Next, when the X-axis movable unit 10 reaches the target coordinate position commanded by the movable head 17, an actuator or the like that forms part of the camera drive mechanism of the movable head 17 is operated to a position where the target reference mark can be captured. The operation of positioning the camera 19 is performed.

  When the camera 19 reaches the reference mark position of the instructed X-axis reference mark row 22, the camera 19 captures the reference mark at the target coordinate position, and from the reference mark coordinates (theoretical coordinates) at the position where the movable head 17 has moved. Is detected (step S3). In this detection, for example, the distance between the center position of the reference mark captured as an image and the center axis of the camera 19 is obtained by image processing. If the resolution of the camera 19 is about 1 μm, the amount of deviation between the reference mark in the X-axis reference mark row 22 and the actual position where the movable head 17 has moved can be detected with substantially the same accuracy.

When the amount of deviation Δx on the X-axis reference mark row 22 side is detected, this time, the amount of deviation Δy in the Y-axis direction is detected. Similar to steps S2 and S3, the movable head 17 is aligned with the origin of the Y axis, and a command value of an arbitrary Y coordinate (X ₀ , Y _i ) is given to the Y axis drive unit 14 as a target coordinate position. 17 is moved to the target coordinate position of the reference mark as the target of the Y-axis reference mark row 23 (step S4).

  When moving to the target coordinate position, the camera 19 images the reference mark at the target coordinate position on the Y-axis reference mark row 23 side, and the amount of deviation Δy from the reference mark coordinate (theoretical coordinate) at the position where the movable head 17 has moved is obtained. It detects (step S5). This step S5 is to perform the same operation as step S3 on the reference mark on the Y-axis reference mark row 23 side.

  The obtained deviation amount Δx between the reference mark of the X-axis reference mark row 22 and the movable head 17 and the deviation amount Δy between the reference mark row of the Y-axis reference mark row 23 and the movable head 17 are respectively set in step S3, In S5, it is stored in the table as a value corresponding to the movement distance.

The shift amounts Δx and Δy are considered to be slightly different depending on the position of the department of the X-axis ball screw 11 and the Y-axis ball screw 14 (movable position of the movable head). The operation of S5 is repeated (step S6). These acquired deviation amounts Δx and Δy are stored for each item such as a movement position in a table for correcting deviation amounts due to temperature changes.
In the above flow, the amount of deviation is measured once each in the X-axis direction and the Y-axis direction. However, a predetermined number of X-axis directions may be measured, and then a predetermined number of Y-axis directions may be measured. .

Next, the operation for correcting the position of the movable head 17 during substrate inspection will be described.
The values of x _i and y _i to be corrected when the movable head 17 is moved to the coordinate positions x _i and y _i are shifted by the temperature rise at the x _i and y _i positions obtained in steps S3 and S5. [Delta] x, [Delta] y only, actual for the movement distance is long, the command value for the target coordinate _{position, (x i -Δx, y i} -Δy) as by shift amount for correcting the command value to be provided. A correction value corresponding to the target coordinate position is read, a command value obtained by adding the correction value to the target coordinate value is given, the X-axis drive unit 10 and the Y-axis drive unit 14 are controlled, and the movable head 17 is set to the target coordinate position. Move (steps S10 to S13). Instead of using the deviation amounts Δx and Δy as they are, for example, a correction coefficient created based on the deviation amount may be used, or a pitch correction value may be used.

In the control at the time of substrate inspection, the values of x and y deviation amounts Δx and Δy serving as correction values are taken out from the respective tables, and correction is performed based on the values of the coordinates (x _i , y _i ) in the X axis direction and the Y direction. Go and give the command value.

  Further, since there is an individual difference for each substrate inspection apparatus, the deviation amount, that is, the correction value is acquired for each apparatus before the inspection is performed, and a coefficient for correction is obtained and stored in a table. Also, during the inspection, the deviation amount is periodically taken back and stored, and correction is performed during the inspection.

  In the above description, the number of movable heads 17 is described. However, a plurality of movable heads 17 may be provided, and a plurality of Y-axis drive units may be provided for each movable head. At this time, as the X-axis drive unit, an X-axis ball screw is provided for each movable head to move the movable head, and the linear guide may be provided for every two movable heads, or may be shared. Furthermore, the movable head may be provided on both sides of the XY plane to inspect the substrate to be inspected from both sides.

DESCRIPTION OF SYMBOLS 10 X-axis drive unit 11 X-axis ball screw 12 X-axis linear guide 13 X-axis servo motor 14 Y-axis drive unit 15 Y-axis ball screw 16 Y-axis servo motor 17 Movable head 18 Probe 19 Camera 20 Control device 21 Stage 22 X-axis reference mark Row 23 Y-axis reference mark row

Claims (8)

An XY orthogonal two-axis drive mechanism that enables a movable head carrying a probe to move forward and backward on an XY plane,
The XY orthogonal two-axis drive mechanism includes an orthogonal X-axis drive unit, a Y-axis drive unit, and a control device that controls driving of the X-axis drive unit and the Y-axis drive unit.
The X-axis drive unit moves the Y-axis drive unit in the X-axis direction by an X-axis ball screw provided on one side in the X-axis direction and a linear guide provided at least on the other side,
The Y-axis drive unit is a movable head position correction method for an XY substrate inspection apparatus, wherein the movable head is moved in the Y-axis direction by a Y-axis ball screw,
Install reference marks with known coordinate values in the X-axis direction and Y-axis direction,
The movable head is moved to the target position of the reference mark in the X-axis direction and the Y-axis direction, the reference mark in the X-axis direction and the Y-axis direction is imaged at the moved position, and the reference at the moved position is taken. A method for correcting a movable head position of an XY substrate inspection apparatus, comprising a step of detecting a deviation amount from a mark. In the XY substrate inspection apparatus movable head position correction method according to claim 1,
A movable head position of an XY substrate inspection apparatus, comprising: a step of correcting command values given to the X-axis drive unit and the Y-axis drive unit based on the detected deviation amount in a substrate inspection step Correction method. In the movable head position correction method of the XY board | substrate inspection apparatus of Claim 1 or 2,
The reference mark is printed or engraved on a member made of a material having a small coefficient of thermal expansion at a cycle of a distance that falls within the visual field range of the camera.   4. The movable head position correction method for an XY substrate inspection apparatus according to claim 1, wherein the detecting step is periodically executed. 5. Head position correction method. An XY orthogonal two-axis drive mechanism that enables a movable head carrying a probe to move forward and backward on an XY plane,
The XY orthogonal two-axis drive mechanism includes an orthogonal X-axis drive unit, a Y-axis drive unit, and a control device that controls driving of the X-axis drive unit and the Y-axis drive unit.
The X-axis drive unit moves the Y-axis drive unit in the X-axis direction by an X-axis ball screw provided on one side in the X-axis direction and a linear guide provided at least on the other side,
The Y-axis drive unit is an XY substrate inspection apparatus that moves the movable head in the Y-axis direction by a Y-axis ball screw,
Reference marks with known coordinate values are provided in the X-axis direction and the Y-axis direction,
The controller is
The movable head is moved to the target position of the reference mark in the X-axis direction and the Y-axis direction, the reference mark in the X-axis direction and the Y-axis direction is imaged at the moved position, and the reference at the moved position is taken. An XY substrate inspection apparatus comprising means for detecting a deviation amount from a mark. In the XY board | substrate inspection apparatus of Claim 5,
The XY substrate inspection apparatus, wherein the control device includes means for correcting command values given to the X-axis drive unit and the Y-axis drive unit based on the detected deviation amount. In the XY board | substrate inspection apparatus of Claim 5 or 6,
The XY substrate inspection apparatus, wherein the reference mark is printed or stamped on a member made of a material having a small coefficient of thermal expansion at a period of a distance that falls within the field of view of the camera. In the XY board | substrate inspection apparatus of any one of Claim 5 to 7,
The XY substrate inspection apparatus, wherein the control device includes means for periodically detecting the shift amount.

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