Mapping device and load port device

Abstract

To detect the storage status of rectangular plate-shaped objects with greater accuracy. [Solution] A mapping device for detecting the storage state of multiple rectangular plate-shaped objects, comprising: a first detection unit having a first detection axis intersecting a first side of the rectangular plate-shaped object and a second side substantially perpendicular to the first side, for detecting the thickness of a first corner; a second detection unit having a second detection axis intersecting a first side and a third side of the rectangular plate-shaped object, for detecting the thickness of a second corner; a first information acquisition unit for acquiring first information relating to the amount of deflection in the first direction of the rectangular plate-shaped object; a correction value calculation unit for calculating a corrected detection value relating to the thickness in the first direction of the rectangular plate-shaped object by performing a correction based on the first information to the sum of the first corner thickness and the second corner thickness or the average value of the first corner thickness and the second corner thickness of the rectangular plate-shaped object; and a discrimination unit for determining the storage state of the rectangular plate-shaped objects using the corrected detection value.

Description

Technical Field

[0001] The present invention relates to a mapping device and a load port device.

Background Art

[0002] A device that transfers a plate-shaped object such as a substrate, like a load port device, is equipped with a mapping device that detects the accommodation state of the object accommodated in a container. The mapping device detects the number and position of the objects accommodated in the container, and also detects whether the objects are normally accommodated in the container (see Patent Document 1). The objects detected by the mapping device include thin plate-shaped materials such as glass substrates in addition to silicon substrates and those obtained by processing the silicon substrates.

[0003] On the other hand, as the objects transported in a semiconductor processing factory are becoming larger and thinner, and the diversification of the objects accommodated and transported in containers is progressing. For example, there is a desire to accommodate a rectangular plate-shaped object larger than a silicon substrate in a sealed container and transport it inside the factory in the same manner as a silicon substrate. As a mapping device adapted to such a rectangular plate-shaped object, for example, one that detects the corners of the rectangular object has been proposed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, the inventors of this application have revealed that even in the detection values ​​obtained by the detection unit that detects the corners of a rectangular object in a mapping device, the influence of the object's deflection cannot be ignored with respect to the detection values ​​in the thickness direction. In other words, although the number of detection units that detect the corners of a rectangular object is smaller than in conventional devices, the detection values ​​in the thickness direction (first direction) are affected by the object's deflection. Therefore, in order to more accurately determine the state of the object's storage (for example, one layer and two layers), it is necessary to reduce or eliminate the influence of the object's deflection included in the detection values.

[0006] The present invention relates to a mapping device that can more accurately detect the state of storage of a rectangular plate-shaped object. [Means for solving the problem]

[0007] To achieve the above objective, the mapping apparatus of the present invention is A mapping device for detecting the state of storage of multiple rectangular plate-shaped objects in a container capable of accommodating them at intervals from one another along a first direction, A first detection unit has a first detection axis that intersects a first side of the rectangular plate-shaped object with a second side substantially perpendicular to the first side, and detects the thickness of a first corner which is the length along the first direction to which the first detection axis is shielded by the rectangular plate-shaped object when the first detection axis is moved along the first direction, The second detection unit has a second detection axis that intersects the first side of the rectangular plate-shaped object with a third side that is substantially perpendicular to the first side and opposite to the second side, and detects the thickness of the second corner, which is the length along the first direction that the second detection axis is shielded by the rectangular plate-shaped object when the second detection axis is moved along the first direction, A first information acquisition unit that acquires first information regarding the amount of deflection in the first direction of the rectangular plate-shaped object, A correction value calculation unit calculates a corrected detected value relating to the thickness of the rectangular plate-shaped object in the first direction by applying a correction based on the first information to the sum of the thickness of the first corner and the thickness of the second corner, or the average value of the thickness of the first corner and the thickness of the second corner for the rectangular plate-shaped object. The system includes a discrimination unit that determines the state of storage of the rectangular plate-shaped object using the corrected detection value.

[0008] In the mapping device according to the present invention, the first corner thickness and the second corner thickness of a rectangular plate-shaped object are detected by a first detection unit and a second detection unit, and a correction value calculation unit corrects the sum or average value of the first corner thickness and the second corner thickness based on information regarding the deflection amount of the rectangular object. In this case, the first information, which is information regarding the deflection amount of the rectangular object, may be, for example, information detected by other detection units of the same mapping device, information transmitted from other mapping devices or control devices to the target mapping device, or information calculated from such information, but is not particularly limited. In such a mapping device, the first corner thickness and the second corner thickness, which are relatively unaffected by the deflection of the object, are detected, and a correction is made to the sum or average value of the first corner thickness and the second corner thickness based on the first information regarding the deflection amount, making it possible to detect the storage state of the rectangular plate-shaped object with greater accuracy. In particular, by using the corrected detection values ​​calculated by the mapping device to determine the storage state of the rectangular plate-shaped object, it is possible to more accurately determine, for example, whether the rectangular plate-shaped object is stored in a single layer or a double layer.

[0009] Furthermore, for example, the device further includes a third detection unit that has a third detection axis substantially parallel to the first side of the rectangular plate-shaped object and longer than the first side, and detects a deflection index value that is the length along the first direction to which the third detection axis is shielded by the rectangular plate-shaped object when the third detection axis is moved along the first direction, The first information acquired by the first information acquisition unit may be the result of the deflection index value detection by the third detection unit.

[0010] The third detection unit detects using a third detection axis that is parallel to the first side and relatively longer, and is therefore more susceptible to the deflection of the rectangular plate-shaped object than the detection values ​​obtained by the first and second detection units. By performing corrections based on the deflection index value, which is greatly affected by the amount of deflection, such a mapping device can effectively reduce or eliminate the influence of the amount of deflection on the detection value, and appropriately detect the state in which the rectangular plate-shaped object is housed.

[0011] Furthermore, for example, the correction value calculation unit may calculate the difference between the deflection index value of each rectangular plate-shaped object and a reference value, and apply a correction amount or correction coefficient proportional to the difference between the deflection index value and the reference value to the sum of the first corner thickness and the second corner thickness of the rectangular plate-shaped object, or the average value of the first corner thickness and the second corner thickness, to calculate the corrected detected value.

[0012] The method for calculating the correction amount by the correction value calculation unit is not particularly limited, but by applying a correction amount or correction coefficient that is proportional to the difference in the deflection index value with respect to the reference value, the correction amount can be calculated accurately with less computation.

[0013] Furthermore, for example, the first detection unit may have a first light-emitting unit and a first light-receiving unit. The second detection unit may also have a second light-emitting unit and a second light-receiving unit. The first detection axis may be characterized by connecting the first light-emitting unit and the first light-receiving unit, and the second detection axis may be characterized by connecting the second light-emitting unit and the second light-receiving unit.

[0014] Examples of the first and second detection units include optical sensors, magnetic sensors, capacitive sensors, and ultrasonic sensors. By using an optical sensor having a light-emitting unit and a light-receiving unit, the shielding length in the first direction of a rectangular object can be measured with high accuracy.

[0015] Furthermore, the mapping arm may have, for example, a widthwise portion extending substantially parallel to the first side of the rectangular plate-shaped object, a first protruding portion projecting substantially parallel to the second side from one side of the widthwise portion, and a second protruding portion projecting substantially parallel to the third side from the other side of the widthwise portion. Either the first light-emitting unit or the first light-receiving unit, and either the second light-emitting unit or the second light-receiving unit, may be installed in the widthwise portion. The other of the first light-emitting unit and the first light-receiving unit may be installed on the first protruding portion. The other of the second light-emitting unit and the second light-receiving unit may be installed on the second protruding portion.

[0016] By using such a mapping arm, the shielding length of a rectangular object in a first direction can be measured accurately and quickly using the first detection unit and the second detection unit.

[0017] Furthermore, for example, the first detection unit may have a first light-emitting unit and a first light-receiving unit. The second detection unit may also have a second light-emitting unit and a second light-receiving unit. The third detection unit may also have a third light-emitting unit and a third light-receiving unit. The mapping arm may have a widthwise portion extending substantially parallel to the first side of the rectangular plate-shaped object, a first protruding portion projecting substantially parallel to the second side from one side of the widthwise portion, and a second protruding portion projecting substantially parallel to the third side from the other side of the widthwise portion. Either the first light-emitting unit or the first light-receiving unit, and either the second light-emitting unit or the second light-receiving unit, may be installed in the widthwise portion. The other of either the first light-emitting unit or the first light-receiving unit, and either the third light-emitting unit or the third light-receiving unit, may be installed on the first protruding portion. The other of either the second light-emitting unit or the second light-receiving unit, and the other of either the third light-emitting unit or the third light-receiving unit, may be installed on the second protruding portion.

[0018] Also, for example, by using such a mapping arm, the first detection unit and the second detection unit can accurately and quickly measure the shielding length of a rectangular object in the first direction. At the same time, for each rectangular object, the third detection unit can obtain the deflection index value as the first information. Therefore, a mapping device having such a mapping arm can quickly determine the accommodation state of a rectangular plate-shaped object.

[0019] Also, for example, it may have a driving unit that moves the mapping arm along the first direction. By the driving unit moving the mapping arm, the first detection axis and the second detection axis sequentially intersect with a plurality of the rectangular plate-shaped objects accommodated in the container, and the first corner thickness and the second corner thickness of the rectangular plate-shaped object may be detected.

[0020] By having such a driving unit, the mapping device can accurately detect the accommodation state of the rectangular plate-shaped objects in the container.

[0021] Also, for example, the load port device according to the present invention includes any one of the above mapping devices, a placement part for placing the container, and a door for opening and closing the lid of the container.

[0022] The mapping device according to the present invention may be used in any device. For example, it can be suitably used as a part of an interface unit for transferring a substrate or the like using a container in a semiconductor factory, such as a load port device provided in a semiconductor processing device.

Brief Description of the Drawings

[0023] [Figure 1] FIG. 1 is a schematic diagram of a load port device having a mapping device according to an embodiment of the present invention. [Figure 2]Figure 2 is an explanatory diagram (partial cross-sectional view) showing the first stage of the detection operation by the mapping device shown in Figure 1. [Figure 3] Figure 3 is an explanatory diagram (partial cross-sectional view) showing the second stage of the detection operation by the mapping device shown in Figure 1. [Figure 4] Figure 4 is an explanatory diagram (partial cross-sectional view) showing the third stage of the detection operation by the mapping device shown in Figure 1. [Figure 5] Figure 5 is a conceptual diagram showing the state inside the container during the detection operation using the mapping device shown in Figure 1. [Figure 6] Figure 6 is a plan view showing the arrangement of the mapping arm, the first to third detection units provided on the mapping arm, and the rectangular plate-shaped object shown in Figures 1 to 3. [Figure 7] Figure 7 is a magnified view of the area around the first protruding portion of the mapping arm shown in Figure 6. [Figure 8] Figure 8 is a magnified view of the area around the first protruding portion of the mapping arm in the modified example. [Figure 9] Figure 9 is a conceptual diagram showing the characteristics of each detection value acquired by the first to third detection units shown in Figure 8, etc. [Figure 10] Figure 10 is a flowchart showing the method for detecting the arrangement state in the mapping device shown in Figure 1. [Figure 11] Figure 11 is a graph showing an example of data detected and calculated using the detection method shown in Figure 10. [Modes for carrying out the invention]

[0024] The present invention will be described below based on embodiments shown in the drawings. Figure 1 is a schematic perspective view of a load port device 10 having a mapping device 20 according to one embodiment of the present invention. The mapping device 20 according to this embodiment is provided around the door 15 of the load port device 10. The mapping device 20 detects the state of storage of a substrate 80 (see Figures 2 and 6), which is a rectangular plate-shaped object housed in a container 70 (see Figure 2) placed on the load port device 10.

[0025] The load port device 10 is used in semiconductor factories, attached to an EFEM (not shown), etc. The load port device 10 functions as an interface for transferring substrates 80, which are transported within the semiconductor factory in a container 70 (see Figure 2), from the container 70 to a predetermined semiconductor processing device. Examples of containers 70 for housing substrates 80 include FOUP, FOSB, and SMIF.

[0026] As shown in Figure 2, the container 70 is capable of accommodating multiple substrates 80 with spacing between them along a first direction D1. As shown in Figure 2, the first direction D1 of the container 70 (downward direction of the container 70) is parallel to the Z-axis direction (up and down direction) when the container 70 is placed on the load port device 10. The container 70 shown in Figure 2 has a main opening 70a (see Figure 3) formed on the side of the container 70 for removing the substrates 80 (FOUP type). However, the opening and closing method of the container that accommodates the substrates 80 as rectangular plate-shaped objects to be detected by the mapping device 20 is not particularly limited, and it may be an opening and closing method different from that of the container 70 shown in Figure 2, such as an SMIF type.

[0027] As shown in Figure 1, the load port device 10 includes, in addition to the mapping device 20, a mounting section 19 on which a container 70 containing the substrate 80 is placed, a frame section 16 attached to close the opening of the EFEM, and a door 15 that opens and closes the lid 74 of the container 70 and the frame opening of the frame section 16. It should be noted that the mapping device 20 is not limited to those provided in the load port device 10, as shown in Figures 1 and 2. A mapping device that detects the state of the substrate 80 contained within a container 70 placed on a device other than the load port device 10, such as a storage rack for the container 70, is also included.

[0028] The mapping device 20 shown in Figures 1 and 2 detects the state of the substrate 80's placement within the container 70. In addition to the mapping arm 54, first detection unit 30, second detection unit 40, and third detection unit 90, which will be described later using Figure 6, the mapping device 20 also has a support structure that supports the mapping arm 54, such as a support arm 63 that supports the mapping arm 54. The mapping device 20 also has a drive unit that moves the mapping arm 54 and the support arm 63. As shown in Figure 2, the drive unit of the mapping device 20 has a first moving means 64 that moves the mapping arm 54, etc., along a first direction D1, and a second moving means 65 that moves the mapping arm 54, etc., in the Y-axis direction.

[0029] Figure 5 is a cross-sectional view of the container 70 that houses the substrate 80, and is a view of the container 70 from the door 15 side (positive Y-axis direction side). Figure 6 is a magnified view of a part of the mapping device 20 shown in Figure 1, and the substrate 80 which is the target of detection by the first detection unit 30, second detection unit 40, and third detection unit 90 of the mapping device 20. In the description of the load port device 10 and the mapping device 20, the vertical direction is the Z-axis direction, the direction perpendicular to the Z-axis in which the mounting unit 19 approaches or moves away from the frame unit 16 is the Y-axis direction, and the direction perpendicular to the Z-axis and Y-axis is the X-axis direction.

[0030] As shown in Figures 2 and 5, multiple substrates 80 are housed in the container 70 at predetermined intervals along the first direction D1. As shown in Figure 6, the substrates 80 are flat plates with a substantially rectangular shape when viewed from the Z-axis direction, and the two widest surfaces of the substrates 80 are housed in the container 70 in a position where they extend substantially horizontally. The container 70 may also be capable of housing objects that are not rectangular in shape, such as circular flat silicon wafers.

[0031] As shown in Figure 6, when the substrate 80 is viewed from the Z-axis direction, the substrate 80 has a first side 82a that is closer to the main opening 70a of the container 70 than the other sides and extends substantially parallel to the opening surface. The substrate 80, which is substantially rectangular, also has a second side 82b substantially perpendicular to the first side 82a, a third side 82c substantially perpendicular to the first side 82a and opposite to the second side 82b, and a fourth side 82d substantially parallel to the first side 82a and opposite to the first side 82a.

[0032] Furthermore, the substrate 80, which is roughly rectangular when viewed from the Z-axis direction, has four corners. Of the four corners of the substrate 80, the first corner 81a shown in Figure 6 is the corner sandwiched between the first side 82a and the second side 82b, and the second corner 81b is the corner sandwiched between the first side 82a and the third side 82c. The first corner 81a and the second corner 81b are located closer to the opening 70a than the center 86 of the substrate 80.

[0033] As shown in Figure 5, the container 70 has a first support member 72a, a second support member 72b, and a third support member 72c, which are support members for the substrate 80, which is a rectangular plate-shaped object. The first to third support members 72a, 72b, and 72c extend in the Y-axis direction, which is perpendicular to the opening 70a of the container 70, and support the substrate 80 from below.

[0034] The first support member 72a and the second support member 72b are positioned near two side walls of the container 70 that are parallel to the YZ plane and perpendicular to the opening 70a. As shown in Figure 5, the first support member 72a supports the portion of the substrate 80 that is closer to the second side 82b than the center 86, and extends a predetermined width inward from the second side 82b, from below. The second support member 72b supports the portion of the substrate 80 that is closer to the third side 82c than the center 86, and extends a predetermined width inward from the third side 82c, from below.

[0035] As shown by the dashed line in Figure 5, the first support member 72a and the second support member 72b are supported by arms extending from the side walls of the container 70, which are parallel to the YZ plane.

[0036] The third support member 72c is positioned so as to overlap the center 86 of the substrate 80 when viewed from the Z-axis direction, which is the first direction D1. The third support member 72c is positioned between the first support member 72a and the second support member 72b, and can support the central portion of the substrate 80 in the X-axis direction from below. The third support member 72c is fixed to the side wall of the container 70 opposite to the opening 70a.

[0037] When viewing the substrate 80 inside the container 70 from the Z-axis direction, which is the first direction D1, none of the first to third support members 72a to 72c intersect the first edge 82a, and their tips on the positive Y-axis side are located closer to the center 86 than the first edge 82a (see Figure 6). Therefore, when viewed from the Z-axis direction, which is the first direction D1, the first to third support members 72a to 72c do not intersect the detection axes 32, 42, and 92 of the first to third detection units 30, 40, and 90, which will be described later, and do not obstruct the detection of the substrate 80 by the first to third detection units 30, 40, and 90.

[0038] As can be seen from Figures 3 and 4, which show an example of the mapping operation performed in the load port device 10, a portion of the mapping device 20 is inserted into the container 70 through the opening 70a. As shown in Figures 3 and 4, at least a portion of the mapping arm 54 of the mapping device 20, which houses the first detection unit 30, the second detection unit 40, and the third detection unit 90, is designed to be inserted into the container 70.

[0039] Figure 6 is a plan view showing the mapping arm 54, first detection unit 30, second detection unit 40, third detection unit 90, and substrate 80 of the mapping device 20 shown in Figure 5. As shown in Figure 6, the mapping arm 54 has a widthwise portion 56 extending substantially parallel to the first side 82a of the rectangular plate-shaped target portion, a first protruding portion 57 projecting substantially parallel to the second side 82b from one side 56a of the widthwise portion 56, and a second protruding portion 58 projecting substantially parallel to the third side 82c from the other side 56b of the widthwise portion 56. In the mapping arm 54, the first protruding portion 57 is provided at the end of one side 56a (negative X-axis side) of the widthwise portion 56 extending in the X-axis direction, and the second protruding portion 58 is provided at the end of the other side 56b (positive X-axis side). The mapping arm 54 is mounted approximately horizontally on the upper end of the support arm 63 shown in Figure 1. As the support arm 63 moves, the mapping arm 54 and the first detection unit 30, second detection unit 40, and third detection unit 90 provided on the mapping arm 54 move.

[0040] As shown in Figures 5 and 6, when the mapping device 20 detects the substrate 80, the widthwise portion 56 of the mapping arm 54 is positioned parallel to the opening 70a of the container 70. In addition, the first protruding portion 57 and the second protruding portion 58 of the mapping arm 54 are positioned to sandwich the substrate 80 from both sides in the X-axis direction.

[0041] As shown in Figure 6, the mapping device 20 has a first detection unit 30, a second detection unit 40, and a third detection unit 90, and each detection unit 30, 40, and 90 detects the substrate 80 inside the container 70. The first detection unit 30 has a first detection axis 32 that intersects the first edge 82a and the second edge 82b of the substrate 80 when the mapping arm 54 moves in a first direction D1 inside the container 70. When the first detection axis 32 is moved along the first direction D1 by the movement of the mapping arm 54, the first detection unit 30 detects the first corner thickness 30a (see Figure 9), which is the length along the first direction D1 where the first detection axis 32 is shielded by the substrate 80 (the first corner 81a).

[0042] More specifically, as shown in Figure 6, the first detection unit 30 is an optical sensor having a first light-emitting unit 34 and a first light-receiving unit 36, and detects the first corner thickness 30a by the change in the amount of light from the first light-emitting unit 34 incident on the first light-receiving unit 36. The first detection axis 32 of the first detection unit 30 connects the first light-emitting unit 34 and the first light-receiving unit 36. Either the first light-emitting unit 34 or the first light-receiving unit 36 ​​is installed in the widthwise portion 56 of the mapping arm 54, and the other of the first light-emitting unit 34 or the first light-receiving unit 36 ​​is installed in the first protruding portion 57. In the mapping device 20, the first light-emitting unit 34 is installed in the widthwise portion 56 and the first light-receiving unit 36 ​​is installed in the first protruding portion 57, but the arrangement of the first light-emitting unit 34 and the first light-receiving unit 36 ​​may be reversed.

[0043] Figure 7 is a magnified view of the vicinity of the tip of the first protruding portion 57 in the mapping arm 54. As shown in Figure 7, the angle θ between the first detection axis 32 and the second side 82b can be, for example, 40 to 50 degrees. By setting the angle θ to 40 degrees or more, the first detection axis 32 can avoid intersecting the notch portion 81aa at the first corner 81a, thereby suppressing variations in the measured values. Furthermore, by setting the angle θ to less than 50 degrees, the deflection influence component included in the detected value of the thickness 30a of the first corner can be suppressed.

[0044] Figure 8 is a conceptual diagram showing the first light receiving unit 136 and the first detection axis 132 of the first detection unit 130 in a modified mapping device 120. As shown in Figure 8, if the substrate 80 does not have a cutout portion 81aa, the angle θ between the first detection axis 132 and the second side 82b can be, for example, 20 degrees or more and less than 40 degrees. The same applies to the angle between the second detection axis 42 and the third side 82c in the second detection unit 40, which will be described later.

[0045] The second detection unit 40 has a second detection axis 42 that intersects the first edge 82a and the third edge 82c of the substrate 80 when the mapping arm 54 moves in the first direction D1 inside the container 70. When the second detection axis 42 is moved along the first direction D1 by the movement of the mapping arm 54, the second detection unit 40 detects the second corner thickness 40a (see Figure 9), which is the length along the first direction D1 where the second detection axis 42 is shielded by the substrate 80 (the second corner 81b).

[0046] More specifically, as shown in Figure 6, the second detection unit 40 is an optical sensor having a second light-emitting unit 44 and a second light-receiving unit 46, and detects the second corner thickness 40a by the change in the amount of light from the second light-emitting unit 44 incident on the second light-receiving unit 46. The second detection axis 42 of the second detection unit 40 connects the second light-emitting unit 44 and the second light-receiving unit 46. Either the second light-emitting unit 44 or the second light-receiving unit 46 is installed in the widthwise portion 56 of the mapping arm 54, and the other of the second light-emitting unit 44 or the second light-receiving unit 46 is installed in the second protruding portion 58. In the mapping device 20, the second light-emitting unit 44 is installed in the widthwise portion 56 and the second light-receiving unit 46 is installed in the second protruding portion 58, but the arrangement of the second light-emitting unit 44 and the second light-receiving unit 46 may be reversed.

[0047] Similarly to the first detection axis 32 of the first detection unit 30 shown in Figure 7, the angle between the second detection axis 42 and the third side 82c of the second detection unit 40 can be set to 40 to 50 degrees. As shown in Figure 8, the first detection unit 30 and the second detection unit 40 are arranged to be mirror-symmetric with respect to a line passing through the center 86 of the substrate 80 and parallel to the second side 82b and the third side 82c. However, the configuration of the first detection unit 30 and the second detection unit 40 is not limited to the example shown in Figure 6, and the first detection unit 30 and the second detection unit 40 may be arranged asymmetrically.

[0048] The third detection unit 90 has a third detection axis 92 that is substantially parallel to the first side 82a of the substrate 80 and longer than the first side 82a. The third detection unit 90 has a second detection axis 42 that intersects the second side 82b and the third side 82c of the substrate 80 when the mapping arm 54 moves in a first direction D1 inside the container 70. When the third detection axis 92 is moved along the first direction D1 by the movement of the mapping arm 54, the second detection unit 40 detects a deflection index value 90a (see Figure 9), which is the length along the first direction D1 that the third detection axis 92 is shielded by the substrate 80 (the portion near the first side 82a, including the entire first side 82a).

[0049] More specifically, as shown in Figure 6, the third detection unit 90 is an optical sensor having a third light-emitting unit 94 and a third light-receiving unit 96, and detects a deflection index value 90a by the change in the amount of light from the third light-emitting unit 94 incident on the third light-receiving unit 96. The third detection axis 92 of the third detection unit 90 connects the third light-emitting unit 94 and the third light-receiving unit 96. Either the third light-emitting unit 94 or the third light-receiving unit 96 is installed on the first protruding portion 57 of the mapping arm 54, and the other of the third light-emitting unit 94 or the third light-receiving unit 96 is installed on the second protruding portion 58. In the mapping device 20, the third light-emitting unit 94 is installed on the first protruding portion 57 and the third light-receiving unit 96 is installed on the second protruding portion 58, but the arrangement of the third light-emitting unit 94 and the third light-receiving unit 96 may be reversed.

[0050] As described above, the first detection unit 30, the second detection unit 40, and the third detection unit 90 of the mapping device 20 are optical sensors (photoelectric sensors), but the first detection unit 30, the second detection unit 40, and the third detection unit 90 are not limited to optical sensors only. For example, the mapping device 20 may use other types of through-beam sensors such as ultrasonic sensors or magnetic sensors.

[0051] Furthermore, the first light-emitting unit 34, second light-emitting unit 44, and third light-emitting unit 94 of the mapping device 20 can be, for example, a visible light LED, an infrared LED, or an ultraviolet LED, but other light-emitting units such as LDs (laser diodes) may also be used, and are not particularly limited. Also, the first light-receiving unit 36, second light-receiving unit 46, and third light-receiving unit 96 of the mapping device 20 can be, for example, a phototransistor, a photodiode, or an infrared detection element, but are not particularly limited.

[0052] As shown in Figure 2, a schematic diagram of the load port device 10, the mapping device 20 has a first moving means 64 and a second moving means 65, which are drive units for moving the mapping arm 54 and the first to third detection units 30, 40, and 90. The first moving means 64 moves the mapping arm 54 along the Z-axis direction, which is the first direction D1, as can be seen from comparing Figures 3 and 4.

[0053] On the other hand, the second moving means 65 shown in Figure 2 moves the mapping arm 54 in the second direction, the Y-axis direction, as can be understood from comparing Figure 2 and Figure 3. The second moving means 65 moves the first to third detection units 30, 40, and 90 in the Y-axis direction by either rotating the support arm 63 or translating the support arm 63 and the mapping arm 54 in the Y-axis direction. The third moving means 66 shown in Figure 2 can move the door 15 independently of the mapping arm 54 and the support arm 63, and is used when opening and closing the lid 74 of the container 70, as will be described later.

[0054] The operation of the load port device 10 during the detection operation of the mapping device 20 will be explained using Figures 2 to 4 and Figure 10. Figure 2 shows the first stage in the detection operation of the substrate 80 in the mapping device 20. In the first stage shown in Figure 2, the container 70 containing the substrate 80 is placed on the mounting section 19 of the load port device 10, but the lid 74 of the container 70 is closed, and the container 70 is not connected to the frame section 16 of the load port device 10. Also, in the state shown in Figure 2, the mapping device 20 itself has not started the detection operation.

[0055] Figure 3 shows the second stage in the detection operation of the substrate 80 in the mapping device 20. In the second stage shown in Figure 3, the container 70 placed on the mounting section 19 is connected to the frame section 16, and the lid 74 of the container 70 is open by the door 15. After the door 15 engages with the lid 74 of the container 70 while engaged with the frame section 16 as shown in Figure 2, the third moving means 66 pulls the door 15 in the positive Y-axis direction as shown in Figure 3, thereby opening the lid 74 of the container 70.

[0056] Furthermore, the second moving means 65 of the mapping device 20 moves the support arm 63 and the mapping arm 54, inserting the first to third detection units 30, 40, and 90 (see Figure 6) installed on the mapping arm 54 into the container 70. As a result, the first to third detection axes 32, 42, and 90 of the first to third detection units 30, 40, and 90 are positioned to intersect the substrate 80 when viewed from above, as shown in Figure 6.

[0057] Furthermore, in the state shown in Figure 3, the first to third detection axes 32, 42, and 92 of the first to third detection units 30, 40, and 90 are positioned higher than the substrate 80 housed on the uppermost shelf of the container 70. In addition, during the operation of inserting the mapping arm 54 and the first to third detection units 30, 40, and 90 into the container 70, the first moving means 64 may move the mapping arm 54 and the support arm 63 in the Z-axis direction to adjust their positions in the Z-axis direction.

[0058] Figure 4 shows the third stage in the detection operation of the substrate 80 by the mapping device 20. In the third stage shown in Figure 4, the first moving means 64, which acts as a drive unit, moves the mapping arm 54 in the Z-axis direction, thereby moving the first to third detection units 30, 40, and 90, which were positioned higher than the substrate 80 housed on the top shelf in Figure 3, to a position lower than the substrate 80 housed on the bottom shelf, as shown in Figure 4.

[0059] In other words, the first moving means 64 moves the mapping arm 54 along the first direction D1, so that the first detection axis 32, the second detection axis 42, and the third detection axis 92 sequentially intersect each of the multiple substrates 80 housed in the container 70. At this time, the first detection unit 30, the second detection unit 40, and the third detection unit 90 output the detection signal that changes due to shielding by the substrates 80 to the calculation unit of the mapping device 20 shown in Figure 4, which has a correction value calculation unit 50 and a discrimination unit 51, etc. The mapping device 20 also has a sensor position detection unit 52, which detects the positions of the first to third detection units 30, 40, and 92 in the Z-axis direction and outputs them to the calculation unit, which has a correction value calculation unit 50 and a discrimination unit 51, etc.

[0060] Figure 10 is a flowchart showing a series of processes for determining the storage state of the substrates 80 in the calculation unit of the mapping device 20. In step S001 shown in Figure 10, the first detection unit 30 and the second detection unit 40 shown in Figure 6 detect the first corner thickness 30a and the second corner thickness 40a for the multiple substrates 80 housed in the container 70.

[0061] Furthermore, in step S002 shown in Figure 10, the third detection unit 90 shown in Figure 6 detects the deflection index value 90a for the multiple substrates 80 housed in the container 70. As will be described later, the detection by the third detection unit 90 in step S002 corresponds to the acquisition of first information regarding the amount of deflection in the first direction D1 of the substrate 80, and the third detection unit 90 of the mapping device 20 functions as a first information acquisition unit that acquires the first information. Note that the processing in steps S001 and S002 shown in Figure 10 is explained as part of the operation of the third stage in the detection operation of the substrate 80 by the mapping device 20 described above.

[0062] Next, in step S003 shown in Figure 10, the correction value calculation unit 50 of the mapping device 20 calculates a corrected detected value 50a (see Figure 11) relating to the thickness of the substrate 80 in the first direction D1, using the detected values ​​detected in steps S001 and S002. That is, in step S003, the correction value calculation unit 50 of the mapping device 20 corrects the sum or average value 39a (see Figure 11) of the first corner thickness 30a and the second corner thickness 40a of the substrate 80 detected in step S001, based on first information relating to the amount of deflection of the substrate 80 in the first direction D1. Furthermore, the correction value calculation unit 50 uses the deflection index value 90a of the substrate 80, which is the detection result of the third detection unit 90 in step S002, as the first information used in step S003.

[0063] More specifically, the correction value calculation unit 50 calculates the difference between the deflection index value 90a of each substrate 80 and a reference value. The reference value used when calculating the difference is not particularly limited, but examples include the maximum value, median value, or minimum value of the deflection index value 90a inside the container 70. Next, for each substrate 80, the correction value calculation unit 50 applies a correction amount or correction coefficient proportional to the difference between the deflection index value 90a and the reference value ("deflection index value 90a" - "reference value") to the sum or average value of the first corner thickness 30a and the second corner thickness 40a of the substrate 80 detected in step S001, and calculates the corrected detected value 50a.

[0064] In step S004 shown in Figure 10, the discrimination unit 51 of the mapping device 20 (see Figures 2-3) uses the corrected detection value 50a (see Figure 11) calculated by the correction value calculation unit 50 in step S003 to determine the storage status of the substrate 80. More specifically, the discrimination unit 51 determines that if the corrected detection value 50a is within a predetermined range, the substrate 80 is properly stored in the corresponding position (shelf). If the corrected detection value 50a falls below the predetermined range, the discrimination unit 51 determines that the substrate 80 is not stored in the corresponding position (shelf) (it is an empty shelf). If the corrected detection value 50a exceeds the predetermined range, the discrimination unit 51 determines that the substrate 80 is abnormally stored in the corresponding position (shelf), such as being stacked in pairs.

[0065] Figure 9 is a conceptual diagram summarizing the characteristics of the first corner thickness 30a detected by the first detection unit 30 of the mapping device 20, the second corner thickness 40a detected by the second detection unit 40, and the deflection index value 90a detected by the third detection unit 90. As shown in Figure 9, the deflection index value 90a detected by the third detection unit 90 is more significantly affected by the amount of deflection of the substrate 80 compared to the first corner thickness 30a and the second corner thickness 40a. On the other hand, the deflection index value 90a is less affected by the stacking of two substrates 80 compared to the first corner thickness 30a and the second corner thickness 40a. The reason for this is complex, but one possible reason is that the deflection of the substrate 80 is clearly expressed as a difference in height between the center and the edge of the substrate 80 in the Y-axis direction, and therefore greatly affects the detected value by the third detection axis 92 that traverses the substrate 80 in the Y-axis direction.

[0066] The mapping device 20 not only detects the first corner thickness 30a and the second corner thickness 40a, which are inherently less affected by the deflection of the substrate 80, but also applies a correction to the sum or average value of the first corner thickness 30a and the second corner thickness 40a based on the deflection index value 90a, which is the first information regarding the amount of deflection. As a result, it is possible to detect with greater accuracy the storage state of the rectangular plate-shaped object, the substrate 80, specifically whether it is in an abnormal storage state such as being stacked in two layers or in a normal storage state.

[0067] Figure 11 is a graph showing a specific example of detecting the storage state of substrates 80 housed in a container 70 using a mapping device 20 similar to those shown in Figures 1 to 7. Figures 11(A) and 11(B) show the detection results by the mapping device 20 for each shelf (Slot 1 to Slot 6) of the container 70. Figure 11(A) shows the deflection index value of 90a (left) and the average values ​​of the first corner thickness (30a) and second corner thickness (40a) (right) for each shelf (Slot 1 to Slot 6), respectively. Note that the substrates 80 are normally housed in Slot 1, Slot 2, Slot 5, and Slot 6, while the substrates 80 are abnormally housed in stacks of two in Slot 3 and Slot 4.

[0068] As shown in Figure 11(A), when comparing only the average values ​​of the first corner thickness 30a and the second corner thickness 40a (39a on the right) for each shelf (Slot 1 to Slot 6), Slot 1, which is normally stored, shows only a small difference from the values ​​of Slots 3 and 4, which are abnormally stored. Therefore, it can be understood that comparing only the average values ​​of the first corner thickness 30a and the second corner thickness 40a (39a on the right) can make it difficult to accurately distinguish between normal and abnormal storage.

[0069] However, regarding Figure 11(A), when comparing the deflection index value of 90a (left) for each shelf (Slot1 to Slot6), it can be seen that only the shelf in Slot1 has a larger value than the other shelves (Slot2 to Slot6). In other words, the larger average value of 39a (right) for the first corner thickness 30a and the second corner thickness 40a in the shelf in Slot1 is thought to be due to the substrate 80 in Slot1 being deflected more than the others.

[0070] On the other hand, Figure 11(B) shows the deflection index value 90a (left) and the corrected detection value 50a for each shelf (Slot1 to Slot6). Comparing the corrected detection values ​​50a, they are clearly divided into two groups: Slot1, Slot2, Slot5, and Slot6, which are normally stored, and Slot3 and Slot4, which are abnormally stored. Therefore, it can be seen that by using the corrected detection values ​​50a, the mapping device 20 can accurately distinguish between normal storage and abnormal storage (double-stacked storage) even when there is variation in the amount of deflection of the substrates 80 stored in each shelf.

[0071] The mapping device 20 and load port device according to the present invention have been described above with reference to embodiments and modifications. However, it goes without saying that the technical scope of the present invention is not limited to the embodiments and modifications described above, and that many other embodiments are included in the technical scope of the present invention. For example, the first information regarding the amount of deflection acquired by the first information acquisition unit of the mapping device 20 is not limited to the deflection index value 90a acquired by the third detection unit 90. Other examples of the first information regarding the amount of deflection include, for example, detection information acquired by the device that performed processing on the target substrate 80 immediately beforehand, or information calculated based on the shape, material, processing history, etc., of the substrate 80. In addition, although the operation of the mapping arm 54 was described using Figures 3 to 5 with the first direction D1 being described as downward, the first direction D1 may also be upward. [Explanation of Symbols]

[0072] 10…Load port device 15... Door 16... Frame part 19… Mounting section 20…Mapping device 64…First means of transportation 65…Second transportation means 30...First detection unit 32...First detection axis 34…First light-emitting section 36...1st light receiving section 39a...Average value 40...Second detection unit 42...Second detection axis 44...Second light-emitting section 46…Second light receiving section 90...Third detection unit 92...Third detection axis 94...Third light-emitting section 96…Third light receiving section 90a... Deflection index value 50...Correction value calculation unit 50a...Corrected detected value 51...Discrimination section 52...Sensor position detection unit 54…Mapping Arm 56…Width direction part 56a...One side 56b...the other side 57...First protruding part 58…Second protruding part 63...Support arm 66…Third transportation means 70…Container 70a…Aperture 72a...First support member 72b...Second support member 72c...Third support member 74…Lid 80... Circuit board 81a...First corner 81b...Second corner 82a... First side 82b...Second side 82c... Third side 82d...Fourth side 86…center

Claims

1. A mapping device for detecting the state of storage of multiple rectangular plate-shaped objects in a container capable of accommodating them at intervals from each other along a first direction, A first detection unit has a first detection axis that intersects a first side of the rectangular plate-shaped object with a second side substantially perpendicular to the first side, and detects a first corner thickness which is the length along the first direction to which the first detection axis is shielded by the rectangular plate-shaped object when the first detection axis is moved along the first direction, The second detection unit has a second detection axis that intersects the first side of the rectangular plate-shaped object with a third side that is substantially perpendicular to the first side and opposite to the second side, and detects the thickness of the second corner, which is the length along the first direction to which the second detection axis is shielded by the rectangular plate-shaped object when the second detection axis is moved along the first direction, A first information acquisition unit that acquires first information regarding the amount of deflection in the first direction of the rectangular plate-shaped object, A correction value calculation unit calculates a corrected detected value relating to the thickness of the rectangular plate-shaped object in a first direction by applying a correction based on the first information to the sum of the thickness of the first corner and the thickness of the second corner of the rectangular plate-shaped object, or the average value of the thickness of the first corner and the thickness of the second corner. A mapping device having a discrimination unit that determines the state of storage of the rectangular plate-shaped object using the corrected detection value.

2. The rectangular plate-shaped object has a third detection axis that is substantially parallel to the first side and longer than the first side, and further comprises a third detection unit that detects a deflection index value which is the length along the first direction to which the third detection axis is shielded by the rectangular plate-shaped object when the third detection axis is moved along the first direction, The mapping apparatus according to claim 1, wherein the first information acquired by the first information acquisition unit is the result of the detection of the deflection index value by the third detection unit.

3. The mapping device according to claim 2, wherein the correction value calculation unit calculates the difference between the deflection index value of each rectangular plate-shaped object and a reference value, and applies a correction amount or correction coefficient proportional to the difference between the deflection index value and the reference value to the sum of the first corner thickness and the second corner thickness or the average value of the first corner thickness and the second corner thickness of the rectangular plate-shaped object to calculate the corrected detection value.

4. The first detection unit has a first light-emitting unit and a first light-receiving unit. The second detection unit has a second light-emitting unit and a second light-receiving unit. The mapping apparatus according to claim 1, characterized in that the first detection axis connects the first light-emitting unit and the first light-receiving unit, and the second detection axis connects the second light-emitting unit and the second light-receiving unit.

5. The mapping arm has a widthwise portion extending substantially parallel to the first side of the rectangular plate-shaped object, a first protruding portion projecting substantially parallel to the second side from one side of the widthwise portion, and a second protruding portion projecting substantially parallel to the third side from the other side of the widthwise portion. Either the first light-emitting unit or the first light-receiving unit, and either the second light-emitting unit or the second light-receiving unit, are installed in the widthwise portion. The other of the first light-emitting unit and the first light-receiving unit is installed on the first protruding portion. The mapping device according to claim 4, wherein the other of the second light-emitting unit and the second light-receiving unit is installed on the second protruding portion.

6. The first detection unit has a first light-emitting unit and a first light-receiving unit. The second detection unit has a second light-emitting unit and a second light-receiving unit. The third detection unit has a third light-emitting unit and a third light-receiving unit. The mapping arm has a widthwise portion extending substantially parallel to the first side of the rectangular plate-shaped object, a first protruding portion projecting substantially parallel to the second side from one side of the widthwise portion, and a second protruding portion projecting substantially parallel to the third side from the other side of the widthwise portion. Either the first light-emitting unit or the first light-receiving unit, and either the second light-emitting unit or the second light-receiving unit, are installed in the widthwise portion. The other of either the first light-emitting unit or the first light-receiving unit, and the other of either the third light-emitting unit or the third light-receiving unit, are installed on the first protruding portion. The mapping device according to claim 2, wherein the other of either the second light-emitting unit or the second light-receiving unit, and the other of either the third light-emitting unit or the third light-receiving unit, are installed on the second protruding portion.

7. The mapping arm has a drive unit that moves it along the first direction, The mapping device according to claim 5 or 6, characterized in that the drive unit moves the mapping arm so that the first detection axis and the second detection axis sequentially intersect with a plurality of rectangular plate-shaped objects housed in the container, and the thickness of the first corner and the thickness of the second corner of the rectangular plate-shaped objects are detected.

8. The mapping device according to claim 7, A mounting section on which the container is placed, A load port device having a door for opening and closing the lid of the container.

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