Mapping device and mapping method

Abstract

A purpose of the present invention is to suppress erroneous determination regarding a housing state of a substrate regardless of the type of the substrate and / or differences in containers.　A load port 4 comprises: a lamp 62; a first camera 63 that is disposed at a first placement position in the left-right direction; a second camera 64 that is disposed at a second placement position in the left-right direction; a motor 58; and a controller 66 that acquires a plurality of pieces of imaging information and performs a housing determination. The plurality of pieces of imaging information include first imaging information, second imaging information, and third imaging information. The first imaging information is obtained by imaging an imaging region 201 when the first camera 63 is positioned at a first thickness position in the thickness direction. The second imaging information is obtained by imaging an imaging region 202 when the second camera is positioned at the first thickness position in the thickness direction. The third imaging information is obtained by imaging the imaging region 201 when the first camera is positioned at a second thickness position in the thickness direction.

Description

Mapping device and mapping method

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

[0002] Patent Document 1 discloses a load port (mapping device) equipped with a mapping sensor. The mapping sensor is configured to detect the storage state of semiconductor wafers (substrates) stored in a container having an opening formed on its side. More specifically, the mapping sensor includes a light-emitting unit and an imaging unit, each disposed near the opening. With the lid of the container removed, light emitted by the light-emitting unit and reflected by the edge surface of the substrate, etc., is detected by multiple cameras included in the imaging unit. As a result, each camera acquires an image for determining the storage state of each substrate.

[0003] Patent No. 7346839

[0004] The angular distribution of the intensity of light emitted by the light-emitting unit and reflected by the edge surface of the substrate may vary depending on the material of the substrate, the shape of the edge surface, the processing state of the edge surface, etc. Furthermore, the angular distribution of the intensity of light emitted by the light-emitting unit and reflected by the inner wall surface of the container may also vary depending on the material, shape, and structure of the container, etc. For this reason, even if the arrangement of each camera is devised so that the storage state of a certain substrate stored in a certain container can be correctly determined, erroneous determination may occur when the type of substrate and / or container is changed. However, it is not practical to change the arrangement of each camera every time the type of substrate and / or container is changed.

[0005] An object of the present invention is to suppress erroneous determination of the accommodation state of a substrate, regardless of differences in the type of substrate and / or container.

[0006] a drive unit that drives the imaging unit to move in a thickness direction of the substrate; an imaging information acquisition unit that acquires a plurality of pieces of imaging information by moving the imaging unit in the thickness direction with the imaging unit capturing images while the light is emitted from the light-emitting unit, while a lid for covering the opening is removed from the container; and a determination unit that performs a determination as to whether the substrate is properly accommodated in the container using the plurality of pieces of imaging information, wherein the imaging unit has a first camera disposed at a first position in a predetermined intersecting direction intersecting with the thickness direction, and a second camera disposed at a first position in a predetermined intersecting direction intersecting with the thickness direction, and a second camera disposed at a second position in a predetermined intersecting direction intersecting with the thickness direction. and a second camera disposed at a second placement position different from the first placement position in the thickness direction, wherein the plurality of pieces of imaging information include: first imaging information obtained by imaging a first imaging area preset for detecting the substrate with the first camera when the first camera is positioned at a first thickness position in the thickness direction; second imaging information obtained by imaging a second imaging area preset for detecting the substrate and having a position in the intersecting direction different from the first imaging area with the second camera when the second camera is positioned at the first thickness position in the thickness direction; and third imaging information obtained by imaging a third imaging area preset for detecting the substrate with the first camera when the first camera is positioned at a second thickness position different from the first thickness position in the thickness direction.

[0007] The detection of the substrate is generally performed using information (hereinafter referred to as determination information) obtained by extracting a portion of each piece of image information. The accuracy of substrate detection generally increases as the difference between the intensity of light reflected from the substrate and the intensity of light reflected from the container (hereinafter referred to as light intensity difference) increases. The intensity difference may vary depending on the substrate and the container, as well as the angle between the substrate and the camera.

[0008] In the present invention, the first imaging region is imaged by the first camera, and the second imaging region is imaged by the second camera. This allows not only the determination of the presence or absence of a substrate but also various determinations (containment determinations) regarding whether the substrate is properly contained in the container. Furthermore, in the present invention, the first camera images the substrate from multiple different positions in the thickness direction (i.e., from multiple different angles). This increases the probability of obtaining determination information with a large difference in light intensity compared to detecting the presence or absence of a substrate based on only one piece of image information. As a result, it increases the probability of detecting the substrate properly. Therefore, regardless of the type of substrate and / or the container, erroneous determinations regarding the containment status of the substrate can be suppressed.

[0009] The mapping device of the second invention is characterized in that, in the first invention, the judgment unit performs judgment A to determine whether the substrate is present or not based on the first imaging information, and judgment B to determine whether the substrate is present or not based on the third imaging information, and judges that the substrate is present if it is judged that the substrate is present in at least either judgment A or judgment B.

[0010] In a situation where it is determined that a substrate is present in at least one of the judgments A and B, the probability that a substrate is present is extremely high. Therefore, the judgment according to the present invention is effective.

[0011] The mapping device of the third invention is characterized in that, in the first or second invention, the judgment unit uses A judgment information, which is part of the first imaging information, and B judgment information, which is part of the third imaging information, for the containment judgment, and the A judgment information includes information on the substrate and information on a first surface, which is one of one or more side surfaces among a plurality of inner wall surfaces contained in the container and which is arranged to partially surround the substrate in the circumferential direction of the substrate, and the B judgment information includes information on the substrate and information on a second surface, which is one of the plurality of inner wall surfaces and which is arranged on one side of the substrate in the thickness direction.

[0012] In the present invention, multiple pieces of determination information obtained by capturing images of a substrate from different angles include information on the inner wall surface as the background of the substrate. Because inner wall surfaces are generally flat, the reflected light from the inner wall surface is weaker than the reflected light from special parts such as protrusions. Therefore, the probability of erroneous determination can be effectively reduced.

[0013] A mapping method of a fourth invention is a mapping method for detecting the accommodation state of a substrate accommodated in a container having an opening on a side by using a mapping device, the mapping device comprising: a light-emitting unit that emits light toward at least the inside of the container; and an imaging unit that performs imaging by sensing reflected light of the light emitted from the light-emitting unit, the imaging unit having one or more cameras, and comprising: an imaging information acquisition step of acquiring a plurality of pieces of imaging information by causing the imaging unit to capture images while emitting light from the light-emitting unit when a lid for covering the opening is removed from the container; and a determination step of making a containment determination as to whether the substrate is normally accommodated in the container using the plurality of pieces of imaging information, the plurality of pieces of imaging information being captured by one of the one or more cameras. The imaging information includes: first imaging information obtained by imaging a first imaging area preset for detecting the substrate with the one camera when the one camera is located at a first thickness position in the thickness direction of the substrate; second imaging information obtained by imaging a second imaging area preset for detecting the substrate and having a position in a predetermined intersecting direction that intersects with the thickness direction different from the first imaging area with the one camera when one of the one or more cameras is located at the first thickness position in the thickness direction; and third imaging information obtained by imaging a third imaging area preset for detecting the substrate with the one camera when one of the one or more cameras is located at a second thickness position different from the first thickness position in the thickness direction.

[0014] The present invention also makes it possible to prevent erroneous determinations regarding the accommodation state of substrates, regardless of differences in the types of substrates and / or containers.

[0015] 1 is a schematic plan view of an EFEM equipped with a load port according to this embodiment and its surroundings. FIG. 2 is a right side view of the load port. FIG. 3 is a diagram schematically showing the positional relationship between a substrate and a camera when viewed from above. (a) and (b) are diagrams showing the operation of the load port. (a) and (b) are diagrams showing the operation of the load port. (a) and (b) are schematic diagrams showing a portion of a plurality of substrates and their surroundings as viewed through the light receiving lenses of each camera. (a) and (b) are diagrams schematically showing the positional relationship between the substrates and a camera when viewed from the right. A diagram showing an imaging area imaged by a camera. A diagram showing an imaging area imaged by a camera. A flowchart showing the overall mapping process. A flowchart showing the judgment process for each substrate. (a) to (d) are diagrams for explaining the accommodation state of the substrates.

[0016] An embodiment of the present invention will be described. For convenience of explanation, the directions shown in FIG. 1 are defined as the front-rear and left-right directions. More specifically, the direction in which an EFEM 1 (described later) and a processing device 6 (described later) are arranged is defined as the front-rear direction. In the front-rear direction, the EFEM 1 side is defined as the front side. In the front-rear direction, the processing device 6 side is defined as the rear side. The direction in which multiple load ports 4 are arranged, which is perpendicular to (intersects with) the front-rear direction, is defined as the left-right direction (intersecting direction in the present invention). The direction perpendicular to both the front-rear direction and the left-right direction is defined as the up-down direction. The up-down direction is a direction parallel to the vertical direction in which gravity acts.

[0017] (Schematic Configuration of Load Port and Its Surrounding Area) The schematic configuration of the load port 4 (mapping device of the present invention) and its surrounding area according to this embodiment will be described with reference to FIG. 1 . FIG. 1 is a schematic diagram of an EFEM 1 equipped with multiple load ports 4 and its surrounding area. "EFEM" is an abbreviation for "Equipment Front End Module." The EFEM 1 is a device for transporting a substrate S between a FOUP 100 (container of the present invention) (described below) placed on each load port 4 and a processing device 6. For example, a semiconductor circuit (not shown) is formed on the substrate S. Examples of types of the substrate S include known semiconductor substrates (including wafers), glass substrates, and glass epoxy substrates. The substrate S has, for example, a substantially rectangular shape when viewed from the top-bottom direction. The substrate S has, for example, an end surface SE (see FIG. 2 ) extending in the vertical direction. The thickness direction of the substrate S is substantially parallel to the vertical direction. The shape of the end surface SE may be substantially parallel to the vertical direction. Alternatively, the shape of the end surface SE may be curved with respect to the vertical direction.

[0018] 1, the EFEM 1 includes a housing 2, a transfer robot 3, a plurality of load ports 4, and a control device 5. A processing device 6 is disposed behind the EFEM 1.

[0019] The EFEM 1 is installed at a predetermined position in, for example, a semiconductor factory. The EFEM 1 transfers substrates S between a FOUP 100 placed on a load port 4 and a processing device 6 using a transfer robot 3 arranged in a transfer space 9 inside a housing 2. "FOUP" is an abbreviation for "Front-Opening Unified Pod." The FOUP 100 is a container that can accommodate multiple substrates S arranged vertically. The FOUP 100 is transferred by, for example, a FOUP transfer device (not shown). The FOUP 100 is transferred between the FOUP transfer device and the load port 4.

[0020] The housing 2 is a box-shaped member having a transfer space 9 in which the substrate S is transferred. The transfer space 9 is separated from the space outside the housing 2 (external space). A plurality of load ports 4 are connected to the front end of the housing 2. A load lock chamber 7 of a processing device 6 is connected to the rear end of the housing 2. The transfer robot 3 transfers the substrate S between the FOUP 100 and the load lock chamber 7.

[0021] The multiple load ports 4 are arranged, for example, side by side in the left-right direction. The multiple load ports 4 are attached to the front end of the housing 2. Each load port 4 is configured to receive a FOUP 100. Each load port 4 is configured to attach and detach a lid 102 (see FIG. 2) to and from a FOUP body 101 (see FIG. 2) of the FOUP 100. Each load port 4 is configured to be able to perform mapping of the multiple substrates S accommodated in the FOUP body 101.

[0022] The control device 5 is electrically connected to a control unit (not shown) of the transfer robot 3, an LP (load port) control device 46 (described later) of the load port 4, and a control unit (not shown) of the processing device 6. The control device 5 is configured to communicate with these control units. The control device 5 may also be electrically connected to a higher-level host computer HC.

[0023] The processing device 6 is a device that performs a predetermined process, such as sputtering or dry etching, on the substrate S. The processing device 6 has, for example, a load lock chamber 7 for temporarily waiting the substrate S, and a processing chamber 8 for performing the predetermined process on the substrate S.

[0024] (Load Port) The configuration of the load port 4 will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is a right side view of the load port 4. Fig. 3 is a diagram schematically showing the positional relationship between the substrate S and a plurality of cameras 61 described below (this positional relationship will be described later).

[0025] The load port 4 is configured to remove the lid 102 of the FOUP 100 from the FOUP body 101 and perform mapping of the multiple substrates S accommodated in the FOUP body 101. As shown in Figure 2, the load port 4 has, for example, a base 41, a door mechanism 42, a support frame 43, a placement unit 44, a scanner unit 45, and an LP control device 46 (see Figure 1).

[0026] The base 41 is a substantially flat member. The base 41 has a substantially rectangular shape when viewed from the front-to-rear direction. The base 41 is arranged to extend in the up-and-down direction. The base 41 is fixed to the EFEM 1. The base 41 is part of a partition wall that separates the transfer space 9 from the external space. The base 41 has a substantially rectangular opening 41a. The opening 41a is arranged in the upper part of the base 41. The opening 41a is large enough to allow the lid 102 of the FOUP 100 to pass through in the front-to-rear direction. The opening 41a is opened and closed by a door main body 50, which will be described later.

[0027] The door mechanism 42 is configured to allow the lid 102 to be attached to and detached from the FOUP body 101. As shown in Fig. 2, the door mechanism 42 includes, for example, a door body 50, a door support portion 53, a guide rail 54, a lifting block 55, a guide rail 56, a motor 57, and a motor 58 (a driving portion of the present invention).

[0028] The door body 50 is a plate-like member. When viewed from the front and rear, the door body 50 has a substantially rectangular shape. The door body 50 is supported by, for example, a door support portion 53. The door body 50 is provided with, for example, a suction holding portion (not shown) and a latch key (not shown). The suction holding portion holds the lid 102 by suction to the front surface of the door body 50. The lid 102 can be fixed to the FOUP body 101 by a locking mechanism (not shown). The latch key operates the locking mechanism to unlock and lock the lid 102 of the FOUP 100.

[0029] The door support portion 53 is a member that supports the door body 50. The door support portion 53 is supported by a guide rail 54 so as to be movable in the front-rear direction. The door support portion 53 is driven to move in the front-rear direction by a motor 57. The door support portion 53 moves in the front-rear direction to move the door body 50 between a closed position (see FIG. 4B) and an open position (see FIG. 5A). The closed position is the position of the door body 50 when the door body 50 blocks the opening 41a of the base 41. The open position is a position rearward of the closed position and is the position of the door body 50 when the door body 50 opens the opening 41a. The guide rail 54 is a member that guides the door support portion 53 in the front-rear direction. The guide rail 54 is provided on a lifting block 55. The lifting block 55 is a member for moving the door body 50 up and down. The lifting block 55 supports the door support portion 53 so as to be movable in the front-rear direction. The lifting block 55 is guided in the vertical direction along the guide rail 56. The lifting block 55 is driven to move in the vertical direction by a motor 58. By moving the lifting block 55 in the vertical direction, the door body 50 moves between the open position (see FIG. 5( a)) and a retracted position (see FIG. 5( b)) that is lower than the open position. The guide rail 56 is a member that guides the lifting block 55 in the vertical direction. The guide rail 56 is attached to the base 41, for example. The guide rail 56 extends in the vertical direction.

[0030] The motor 57 is configured to drive the door support portion 53 to move in the front-rear direction. The motor 57 is, for example, a known stepping motor driven by a pulse signal. The motor 57 is configured to be controlled by the LP control device 46 to control the position of the door support portion 53 in the front-rear direction.

[0031] The motor 58 is configured to drive the lifting block 55 to move up and down. The motor 58 is, for example, a known stepping motor driven by a pulse signal. The motor 58 is controlled by the LP control device 46 to control the vertical position of the door support portion 53.

[0032] The support frame 43 is a member for supporting the placement unit 44. The support frame 43 is fixed to the base 41. The support frame 43 is disposed so as to protrude forward from a vertical midpoint of the base 41. The placement unit 44 is a platform-shaped member on which the FOUP 100 is placed. The placement unit 44 is supported by the support frame 43. The placement unit 44 is configured to be movable in the front-rear direction relative to the support frame 43. The placement unit 44 is configured to be movable by a drive mechanism (not shown) between a predetermined transfer position (see FIG. 4A) and a lid opening / closing position (see FIG. 4B) behind the transfer position. The transfer position is the position of the placement unit 44 when the FOUP 100 is ready to be transferred to and from a FOUP transport device (not shown).

[0033] The scanner unit 45 is for detecting a plurality of substrates S in the FOUP 100. The scanner unit 45 is disposed, for example, in the transfer space 9. The scanner unit 45 may be fixed, for example, to the door body 50. This allows the scanner unit 45 to be driven by a motor 58 to move up and down integrally with the door body 50. As shown in FIG. 3 , the scanner unit 45 has a plurality of cameras 61, a light 62 (a light-emitting unit of the present invention), a trigger sensor 65, and a controller 66 (an imaging information acquisition unit and a determination unit of the present invention).

[0034] Each of the multiple cameras 61 is a device for acquiring imaging data (imaging information of the present invention) of multiple substrates S. Each camera 61 is configured and arranged to capture, for example, multiple substrates S at once. Here, multiple substrates S refer to, for example, a portion of all substrates S housed in the FOUP 100. In this embodiment, "imaging" or "performing imaging" refers to recording (i.e., photographing) an image of an object using each camera 61. Each camera 61 is configured and arranged to capture a portion of the substrate S in the left-right direction. Each camera 61 is configured to capture at least a portion of the end surface SE of the substrate S (more specifically, the rear end surface of the substrate S). The multiple cameras 61 may be arranged, for example, above the door body 50 and aligned in the left-right direction. Each camera 61 is electrically connected to the controller 66. Each camera 61 includes, for example, a light-receiving lens 61a and an imaging element (not shown). The light-receiving lens 61a is a condensing member configured to receive light and focus it on the imaging element. The surface of the light receiving lens 61a faces, for example, the front side (FOUP side). The imaging element is a known device such as a CCD. The imaging element senses light, converts it into an electrical signal, and transmits the electrical signal to the controller 66. The combination of the multiple cameras 61 corresponds to the imaging unit of the present invention. That is, in this embodiment, the imaging unit of the present invention has multiple cameras 61.

[0035] The lighting 62 is, for example, a device for illuminating the interior of the FOUP 100 substantially uniformly in the left-right direction. The lighting 62 includes, for example, a plurality of LED elements (not shown). The plurality of LED elements (not shown) are arranged, for example, to form a substantially linear row extending in the left-right direction. Furthermore, it is preferable that a plurality of such rows of LED elements are arranged in the vertical direction. Alternatively, the lighting 62 may include one or more LED elements (not shown) and a diffusion plate (not shown) arranged in front of the one or more LED elements (on the FOUP 100 side in the front-to-back direction). With the above configuration, light (irradiation light) with various directional components in the left-to-right and front-to-back directions is irradiated from the lighting 62 toward at least the interior of the FOUP 100. Although multiple lighting elements 62 are illustrated in FIG. 3 , the number of lighting elements 62 may be one.

[0036] A portion of the illumination light emitted from the illumination 62 and traveling forward is reflected backward (reflected light) by the substrate S or an inner wall surface 113 described below. In particular, the reflected light that is specularly reflected backward (toward the opening of the present invention) by the end surface SE (rear end surface) of the substrate S is used to detect the substrate S. A portion of the illumination light (see the dashed line in FIG. 3 ) is specularly reflected by the end surface SE and then sensed by one of the multiple cameras 61. The imaging element of each camera 61 senses the reflected light to image a portion of the rear end surface of the substrate S in the left-right direction and the background portion, thereby obtaining imaging data. The imaging data obtained by the imaging element is transferred to the controller 66.

[0037] The trigger sensor 65 is a sensor used to determine the timing at which the multiple cameras 61 start capturing images. More specifically, the trigger sensor 65 is configured to detect the movement of the door support portion 53, for example, when a portion of the door support portion 53 moves up or down. The trigger sensor 65 may be, for example, a known photointerrupter. The photointerrupter has a light-emitting portion and a light-receiving portion (not shown), and the light (transmitted light) emitted from the light-emitting portion is detected by the light-receiving portion. As shown in FIG. 2 , the trigger sensor 65 is disposed, for example, inside the support frame 43 and immediately in front of the base 41. That is, when the door body 50 is in at least the open position, the trigger sensor 65 is located near the door support portion 53 and is configured to detect, for example, the door support portion 53. The door support portion 53 includes, for example, a light-blocking portion (not shown) that is movable between a position that blocks and a position that does not block the light emitted from the light-emitting portion of the trigger sensor 65. For example, when the transmitted light is blocked by the light-blocking portion, the trigger sensor 65 may send a signal (trigger signal) indicating that the door support portion 53 has been detected to the controller 66. For example, when the trigger sensor 65 detects transmitted light that is no longer blocked as the door support portion 53 moves downward, the trigger sensor 65 may send a signal indicating that the door support portion 53 is no longer detected to the controller 66.

[0038] The trigger sensor 65 may have, for example, a photoreflector (a reflective optical sensor) instead of a photointerrupter. Alternatively, the trigger sensor 65 may not be provided. In this case, the LP control device 46 may determine the timing to start imaging based on, for example, the number of pulse signals (number of steps) sent from the LP control device 46 to the motor 58.

[0039] The controller 66 is for executing the mapping process described below. The controller 66 includes a CPU, ROM, and RAM (memory), all of which are not shown. The controller 66 performs calculations for the mapping process using the CPU in accordance with a program stored in the ROM. The controller 66 is electrically connected to the LP control device 46, the multiple cameras 61, and the trigger sensor 65. The controller 66 may have a known internal storage, such as a known NAND flash memory, HDD, or SSD, all of which are not shown.

[0040] The LP control device 46 includes a CPU, ROM, and RAM (memory), none of which are shown. The LP control device 46 controls each mechanism of the load port 4 using the CPU in accordance with a program stored in the ROM. The LP control device 46 also communicates with the control device 5 of the EFEM 1 and the host computer HC, etc. The LP control device 46 also sends information related to the mapping process to the controller 66 (described below).

[0041] (FOUP) Next, a more specific example of the configuration of the FOUP 100 will be described with reference to Figures 2 and 3. The front, rear, left, and right directions shown in Figure 3 are directions for the sake of convenience when an opening 114, which will be described later, faces rearward. It should be noted that the "left" and "right" shown in Figure 3 are opposite to the left and right, respectively, on the plane of the paper on which Figure 3 is drawn.

[0042] The FOUP 100 is a container having a generally rectangular parallelepiped shape. The FOUP 100 is configured to be able to accommodate a plurality of substrates S arranged vertically. As shown in FIGS. 2 and 3 , the FOUP 100 has a FOUP body 101 and a lid 102. The FOUP body 101 is a member having a generally rectangular parallelepiped shape. The FOUP body 101 can be supported by the mounting portion 44. The FOUP body 101 has, for example, a wall portion 111, an opening 112, and a plurality of poles P.

[0043] The wall 111 is a substantially rectangular parallelepiped member arranged to surround the internal space of the FOUP 100. The wall 111 is formed by, for example, a plurality of substantially flat plate-shaped members such as acrylic plates fixed to one another with fasteners (not shown). The wall 111 has a plurality of inner wall surfaces 113 (see FIGS. 2 and 3). The opening 112 is arranged, for example, at the rear end (side surface) of the FOUP body 101. The opening 112 has an opening 114 that is substantially rectangular when viewed from the front-to-rear direction.

[0044] Each of the multiple inner wall surfaces 113 is arranged to face the inside of the FOUP 100. Each inner wall surface 113 has, for example, a substantially rectangular shape. The multiple inner wall surfaces 113 include a back surface 113B, an upper surface 113U (see FIG. 2), a lower surface 113D (see FIG. 2), a left side surface 113L (see FIG. 3), and a right side surface 113R (see FIG. 3). The back surface 113B is the inner wall surface 113 arranged at the front-to-back position among the multiple inner wall surfaces 113. In FIG. 3, the back surface 113B faces the rear side (i.e., toward the opening 114 in the front-to-rear direction). The back surface 113B extends in the up-down and left-to-right directions. The back surface 113B is arranged on the opposite side of the opening 114 across the center of the FOUP body 101 in the front-to-rear direction. The top surface 113U is connected to the top end of the back surface 113B and extends to the rear end of the FOUP body 101 in the front-to-rear direction. The top surface 113U faces downward. The bottom surface 113D is connected to the bottom end of the back surface 113B and extends to the rear end of the FOUP body 101 in the front-to-rear direction. The bottom surface 113D faces upward. The left side surface 113L is connected to the left end of the back surface 113B, the left end of the top surface 113U, and the left end of the bottom surface 113D, respectively, and extends to the rear end of the FOUP body 101 in the front-to-rear direction. The left side surface 113L faces right. The right side surface 113R is connected to the right end of the back surface 113B, the right end of the top surface 113U, and the right end of the bottom surface 113D, respectively, and extends to the rear end of the FOUP body 101 in the front-to-rear direction. The right side surface 113R faces left.

[0045] Depending on the type of FOUP 100, protrusions (not shown) may be provided on at least a portion of the inner wall surface 113. The protrusions may cause specular reflection of illumination light toward the opening side.

[0046] The multiple poles P are used to support multiple substrates S in a substantially horizontal position. The multiple poles P are arranged in a substantially rectangular parallelepiped space surrounded by the FOUP body 101. Each of the multiple poles P is, for example, a substantially rod-shaped member extending in the front-rear direction. Each of the multiple poles P is fixed to, for example, the rear surface 113B. A portion of a substrate S is placed on one of the poles P. As shown in FIG. 2 , the multiple poles P are arranged vertically in a row corresponding to the multiple substrates S. As shown in FIG. 3 , the multiple poles P are arranged horizontally. In other words, the multiple poles P include multiple first poles P1, multiple second poles P2, and multiple third poles P3. The multiple first poles P1 are arranged, for example, immediately to the left of the right side surface 113R and arranged vertically. The multiple second poles P2 are arranged, for example, at approximately the center of the FOUP body 101 in the left-right direction and arranged vertically. The multiple third poles P3 are arranged, for example, near the left side surface 113L, and are aligned in the vertical direction. The numbers of first poles P1, second poles P2, and third poles P3 are the same. One first pole P1, one second pole P2, and one third pole P3 are provided corresponding to one substrate S. A set of first pole P1, second pole P2, and third pole P3 are arranged at approximately equal positions in the vertical direction to support one substrate S. The space for supporting one substrate S is called a slot. In other words, the FOUP 100 has multiple slots aligned in the vertical direction.

[0047] The lid 102 is configured to open and close the opening 114. The lid 102 is attached to and detached from the FOUP body 101 by the load port 4. The lid 102 has a locking mechanism (not shown) that can change the state of the lid 102 between a state where it is fixed to the FOUP body 101 and a state where it is released from the FOUP body 101. The locking mechanism is unlocked and locked by a latch key (not shown).

[0048] (Basic Operation of Load Port) The basic operation of the load port 4 will be described with reference to Figures 4(a) to 5(b). Figures 4(a) to 5(b) are right side views of the load port 4 in operation.

[0049] First, the FOUP 100 is placed on the placement unit 44 (see FIG. 4( a)). The LP control unit 46 moves the placement unit 44 from the transfer position (see FIG. 4( a)) to the lid open / close position (see FIG. 4( b)). Next, the LP control unit 46 adsorbs and holds the lid 102 on the suction holding unit of the door body 50, and causes the latch key to unlock the lock mechanism of the lid 102. Furthermore, the LP control unit 46 controls the motor 57 to move the door support unit 53 rearward (see the rightward arrow in FIG. 5( a)). This moves the door body 50 from the predetermined closed position (see FIG. 4( b)) to the open position (see FIG. 5( a)). As a result, the lid 102 is removed from the FOUP body 101.

[0050] With the lid 102 removed from the FOUP body 101, the LP control device 46 controls the motor 58 to move the door body 50 from the open position (see FIG. 5( a)) to the retracted position (see FIG. 5( b)). Accordingly, the multiple cameras 61 and the like of the scanner unit 45 move downward integrally with the door body 50. In response to a command from the controller 66, the multiple cameras 61 capture images of a predetermined area (image capture area 200 shown in FIGS. 8 and 9) described below at predetermined positions in the vertical direction, and acquire image data. The controller 66 performs a mapping process based on the image data acquired by the multiple cameras 61. The mapping process includes a determination of the storage status of each of the multiple substrates S. Details of the mapping process will be described later.

[0051] After the mapping process is completed, the transfer robot 3 starts transferring the substrates S between the FOUP 100 and the processing device 6. The processing device 6 sequentially performs predetermined processing on some or all of the substrates S. The processed substrates S are returned to the FOUP 100 by the transfer robot 3. After all of the substrates S have been returned to the FOUP 100, the LP control device 46 causes the door mechanism 42 and the like to perform the reverse operation of opening the lid 102, and attaches the lid 102 to the FOUP 101 body. In this manner, a series of processes are performed from when the FOUP 100 is transferred to the load port 4 until it is ready for removal.

[0052] Here, the angular distribution of the intensity of light emitted by the illumination 62 and reflected by the edge surface SE of the substrate S may vary depending on the material of the substrate S, the shape of the edge surface SE, and the processing state of the edge surface SE. Furthermore, the angular distribution of the intensity of light emitted by the illumination 62 and reflected by the inner wall surface 113 of the FOUP 100 may also vary depending on the material, shape, and structure of the FOUP 100. Therefore, even if the arrangement of each camera 61 is devised to correctly determine the storage state of a certain substrate S stored in a certain FOUP 100, erroneous determination may occur when the type of substrate S and / or the FOUP 100 changes. However, it is not realistic to change the arrangement of each camera 61 every time the type of substrate S and / or the FOUP 100 changes. Therefore, in order to suppress erroneous determination of the storage state of the substrate S regardless of differences in the type of substrate S and / or the FOUP 100, the load port 4 has the following configuration. In particular, the multiple cameras 61 are configured as follows.

[0053] As described above, the scanner unit 45 has a plurality of cameras 61 and a light 62. As shown in Fig. 3, the plurality of cameras 61 includes, for example, a first camera 63 and a second camera 64.

[0054] (Camera Specifications) Examples of specifications of each camera 61 will be described. The first camera 63 is, for example, a low-magnification camera with a large angle of view. The horizontal angle of view of the first camera 63 is preferably, for example, 100° or more. More specifically, the horizontal angle of view is preferably 100° or more and 150° or less. The vertical angle of view of the first camera 63 is preferably, for example, 53° or more. More specifically, the vertical angle of view is preferably 53° or more and 100° or less. The resolution of the first camera 63 is, for example, 1.2 million pixels. The imaging axis of the first camera 63 is, for example, approximately parallel to the front-to-rear direction (in other words, approximately horizontal). The horizontal angle of view, vertical angle of view, resolution, and orientation of the imaging axis of the first camera 63 are not limited to those described above.

[0055] The second camera 64 is, for example, a high-magnification camera with a smaller angle of view than the first camera 63. The horizontal angle of view of the second camera 64 is preferably, for example, 30° or more and 35° or less. The horizontal angle of view is particularly preferably 34° or more. The vertical angle of view of the second camera 64 is preferably larger than the horizontal angle of view. Specifically, the vertical angle of view is preferably 53° or more. More specifically, the vertical angle of view is preferably 53° or more and 100° or less. The resolution of the second camera 64 is, for example, 1.2 million pixels. The imaging axis of the second camera 64 is, for example, approximately parallel to the front-to-rear direction (in other words, approximately horizontal). The horizontal angle of view, vertical angle of view, resolution, and orientation of the imaging axis of the second camera 64 are not limited to those described above.

[0056] (Overview of Camera Arrangement) The arrangement of each camera 61 will be described with reference to Fig. 3 and Figs. 6(a) to 7(b). Figs. 6(a) and 6(b) are schematic diagrams showing a portion of a plurality of substrates S and their surroundings as viewed through the light receiving lens 61a of each camera 61. Figs. 7(a) and 7(b) are schematic diagrams showing the positional relationship between the substrates S and the cameras 61 as viewed from the right. The first camera 63 is arranged at a predetermined first arrangement position in the left-right direction. The second camera 64 is arranged at a second arrangement position different from the first arrangement position in the left-right direction.

[0057] As shown in FIG. 3 , the first camera 63 is disposed, for example, between the first pole P1 and the second pole P2 in the left-right direction. The first camera 63 is disposed at an appropriate position so that reflected light specularly reflected from the end face SE near the first pole P1 and reflected light specularly reflected from the end face SE near the second pole P2 travels toward the first camera 63. The distance between the first camera 63 and the first pole P1 in the left-right direction is preferably shorter than the distance between the first camera 63 and the second pole P2 in the left-right direction. The second camera 64 is disposed, for example, between the second pole P2 and the third pole P3 in the left-right direction. The second camera 64 is disposed at an appropriate position so that reflected light specularly reflected from the end face SE located near the third pole P3 travels toward the second camera 64. The distance between the second camera 64 and the third pole P3 in the left-right direction is preferably shorter than the distance between the second camera 64 and the second pole P2 in the left-right direction.

[0058] Each of the first camera 63 and the second camera 64 is configured to be able to simultaneously capture images of a plurality of substrates S accommodated in a plurality of vertically adjacent slots, for example. For example, as shown in Fig. 6(a), images of a plurality of substrates S can be captured at once through the light receiving lens 61a (light receiving lens 63a) of the first camera 63. Furthermore, for example, as shown in Fig. 6(b), images of a plurality of substrates S can be captured at once through the light receiving lens 61a (light receiving lens 64a) of the second camera 64.

[0059] In other words, even if the vertical position of each camera 61 is changed to some extent, the cameras 61 can capture images of the same substrate S from different angles. For example, assume that the camera 61 is positioned at approximately the same vertical position as one of the substrates S (substrate S1) (see FIG. 7( a)). Hereinafter, for convenience of explanation, the vertical position of the camera 61 will be referred to as the first thickness position. When the camera 61 is positioned at the first thickness position, a virtual line L1 passing through the vertical center of the end surface SE1 of the substrate S1 and the vertical center of the light receiving lens 61a of the camera 61 is approximately horizontal. Here, in FIG. 7( a), the area between the two dashed two-dot lines indicates the vertical area that the camera 61 can capture (i.e., the imaging area 200, described later). When the camera 61 is positioned at the first thickness position, the camera 61 can capture an image of the substrate S1 from the front.

[0060] Next, assume that the camera 61 is positioned at approximately the same vertical position as the substrate S2, which is positioned adjacent to and below the substrate S1 (see FIG. 7B). Hereinafter, for convenience of explanation, the vertical position of the camera 61 is referred to as the second thickness position. When the camera 61 is positioned at the second thickness position, a virtual line L2 passing through the vertical center of the end surface SE2 of the substrate S2 and the vertical center of the light receiving lens 61a of the camera 61 is approximately horizontal. In FIG. 7B, the area between the two dotted lines indicates the imaging area 200. At this time, the substrate S2 can be imaged by the camera 61. Furthermore, in FIG. 7B, a virtual line L3 passing through the vertical center of the end surface SE1 of the substrate S1 and the vertical center of the light receiving lens 61a of the camera 61 is inclined with respect to the horizontal. This line is included in the imaging area 200. Therefore, the camera 61 can simultaneously capture an image of the substrate S2 from the front and an image of the substrate S1 from diagonally below. In this way, the camera 61 can capture images of the substrate S1 from a plurality of different angles in the vertical direction. The same applies to the other substrates S.

[0061] For convenience of explanation, the vertical distance between the first thickness position and the second thickness position is referred to as a differential distance, which is approximately equal to the vertical length of each of the plurality of slots.

[0062] (Imaging Area and Imaging Data) Next, the imaging area 200 and imaging data will be described in more detail with reference to Figs. 8 and 9. The imaging area 200 refers to the entire area that can be imaged at once by the multiple cameras 61. The imaging area 200 changes depending on the positions of the multiple cameras 61 in the up-down direction. Figs. 8 and 9 are diagrams showing examples of the imaging area 200. More specifically, Fig. 8 shows the imaging area 200 when the multiple cameras 61 are located at the first position described above. Fig. 9 shows the imaging area 200 when the multiple cameras 61 are located at the second position described above.

[0063] The imaging region 200 includes an imaging region 201 and an imaging region 202. The first camera 63 is configured and arranged to capture an image of the imaging region 201 (see FIGS. 8 and 9 ) included in the imaging region 200. In FIGS. 8 and 9 , the imaging region 201 is shown in a rectangular shape for ease of viewing. As shown in FIGS. 8 and 9 , the imaging region 201 has a length in the vertical direction that is sufficient to accommodate multiple substrates S and multiple poles P. The imaging region 201 extends in the horizontal direction, for example, from a position to the right of the first pole P1 to a position to the left of the second pole P2. Hereinafter, the imaging data obtained by capturing an image of the imaging region 201 will also be referred to as low-magnification data.

[0064] The second camera 64 is configured and arranged to capture an image of an imaging area 202 (see FIGS. 8 and 9 ) included in the imaging area 200. In FIGS. 8 and 9 , the imaging area 202 is shown in a rectangular shape for ease of viewing. As shown in FIGS. 8 and 9 , the imaging area 202 has a length in the vertical direction that is sufficient to accommodate multiple substrates S and multiple poles P. The imaging area 202 extends in the horizontal direction, for example, from a position to the right of the third pole P3 to a position to the left of the third pole P3. Hereinafter, the imaging data obtained by capturing an image of the imaging area 202 will also be referred to as high-magnification data.

[0065] A plurality of different imaging areas 200 are imaged depending on the position of the camera 61 in the vertical direction. This allows a plurality of different imaging data to be obtained. Hereinafter, for convenience of explanation, imaging data obtained by two cameras 61 imaging the imaging area 200 once at one location in the vertical direction will be referred to as one unit of imaging data. In other words, multiple units of imaging data are obtained by imaging the imaging area 200 multiple times at multiple locations in the vertical direction. As will be described later, in this embodiment, the accommodation state of one substrate S is determined using two units of imaging data. For example, when the accommodation state of the substrate S1 is determined, two units of imaging data are used, including one unit of imaging data related to the imaging area 200 shown in FIG. 8 and one unit of imaging data related to the imaging area 200 shown in FIG. 9.

[0066] (Determination Area and Determination Data) A portion of each piece of imaging data is extracted to determine the accommodation state of the substrate S. For convenience of explanation, the area related to the extracted data will be referred to as the determination area hereinafter. Furthermore, for convenience of explanation, the data related to each determination area (i.e., the extracted data) will be referred to as the determination data. As shown in FIGS. 8 and 9 , the imaging area 200 includes, for example, three determination areas 210 and three determination areas 220. To summarize, when determining the accommodation state of one substrate S, the determination data related to the three determination areas 210 among the determination data included in the first unit of imaging data and the determination data related to the three determination areas 220 among the determination data included in the second unit of imaging data are used.

[0067] The arrangement of each determination area will be described. The three determination areas 210 are aligned in the left-right direction. More specifically, two of the three determination areas 210 (determination areas 211 and 212) are included in the imaging area 201. The determination areas 211 and 212 are, for example, approximately the center of the imaging area 201 in the up-down direction and areas nearby there. The determination area 211 is an area nearby the position where the first pole P1 is located in the left-right direction. The determination area 212 is an area nearby the position where the second pole P2 is located in the left-right direction. The remaining determination area 210 (determination area 213) is included in the imaging area 202. The determination area 213 is an area nearby the position where the third pole P3 is located in the up-down direction, for example.

[0068] The three determination regions 220 are located above the three determination regions 210 by the above-mentioned differential distance and are aligned in the left-right direction. More specifically, two of the three determination regions 220 (determination regions 221 and 222) are included in the imaging region 201. The determination region 221 is an area near the position where the first pole P1 is located in the left-right direction. The determination region 222 is an area near the position where the second pole P2 is located in the left-right direction. The remaining determination region 220 (determination region 223) is included in the imaging region 202. The determination region 223 is an area near the position where the third pole P3 is located in the left-right direction.

[0069] The position of each camera 61 will be described in further detail with reference to FIGS. 3, 8, and 9. As shown in FIG. 3, when the camera 61 captures the imaging area 200, the camera 61 focuses reflected light using the light-receiving lens 61a. Generally, the lens's principal points (front and rear principal points), foci (front and rear foci), and nodal points (front and rear nodal points) are predetermined according to the lens's specifications. While not shown, in this embodiment, for convenience of explanation, the front nodal point of the light-receiving lens 61a (the center point of the surface of the light-receiving lens 61a facing the substrate S) is defined as the light-receiving point RP. The light-receiving point RP associated with the light-receiving lens 63a of the first camera 63 is referred to as the first light-receiving point RP1. The light-receiving point RP associated with the light-receiving lens 64a of the second camera 64 is referred to as the second light-receiving point RP2.

[0070] 3, 8, and 9, a predetermined point included in each determination region and included in the region where the end surface SE is assumed to exist is referred to as a detection target point SP for convenience of explanation. The positions of the detection target points SP in the up-down, left-right, and front-rear directions are set in advance according to the arrangement of the lighting 62 and the specifications and arrangement of the camera 61.

[0071] For ease of explanation, the detection target point SP included in the judgment area 211 will be called detection target point SP1. The detection target point SP included in the judgment area 212 will be called detection target point SP2. The detection target point SP included in the judgment area 213 will be called detection target point SP3. The detection target point SP included in the judgment area 221 will be called detection target point SP4. The detection target point SP included in the judgment area 222 will be called detection target point SP5. The detection target point SP included in the judgment area 223 will be called detection target point SP6.

[0072] As shown in FIG. 3, the detection target points SP1 and SP4 may be located, for example, to the left of the first pole P1 (i.e., more inward in the left-right direction than the first pole P1). As shown in FIG. 3, the detection target points SP2 and SP5 may be located, for example, at approximately the same position as the center position of the second pole P2 in the left-right direction. As shown in FIG. 3, the detection target points SP3 and SP6 may be located, for example, to the right of the third pole P3 (i.e., more inward in the left-right direction than the third pole P3). The positions of the detection target points SP are not limited to those described above. For example, one or more detection target points SP may be set directly above the corresponding pole P.

[0073] The first camera 63 captures an image of an imaging area 201 (see FIGS. 8 and 9) including detection target points SP1, SP2, SP4, and SP5. The second camera 64 captures an image of an imaging area 202 (see FIGS. 8 and 9) including detection target points SP3 and SP6. In this way, the multiple (two) cameras 61 capture images of an area including multiple (six in total) detection target points SP on each board S.

[0074] As shown in FIG. 3 , for convenience of explanation, a virtual line passing through a predetermined light receiving point RP and a predetermined detection target point SP is referred to as a virtual line VL. For example, the virtual line VL passing through the first light receiving point RP1 and the detection target point SP1 is referred to as a first virtual line VL1. The virtual line VL passing through the first light receiving point RP1 and the detection target point SP2 is referred to as a second virtual line VL2. The virtual line VL passing through the second light receiving point RP2 and the detection target point SP3 is referred to as a third virtual line VL3. In this embodiment, the first virtual line VL1 intersects with, for example, the right side surface 113R of the FOUP 100. The second virtual line VL2 and the third virtual line VL3 intersect with, for example, the left side surface 113L of the FOUP 100. This arrangement minimizes the inclusion of image data related to the back surface 113B in image data related to each determination area 210.

[0075] As shown in Fig. 7B, some of the imaginary straight lines VL (for example, the imaginary straight line VL corresponding to the determination area 210 shown in Fig. 9) extend in a substantially horizontal direction. Other imaginary straight lines VL (for example, the imaginary straight line VL corresponding to the determination area 220 shown in Fig. 9) extend obliquely upward and forward when viewed from the left and right. As a result, the other imaginary straight lines VL intersect with, for example, the upper surface 113U.

[0076] (Mapping Process) Next, an example of the mapping process (mapping method) executed by the load port 4 will be described mainly with reference to Fig. 10. Fig. 10 is a flowchart showing the entire mapping process.

[0077] The initial state is as follows: A FOUP 100 containing a plurality of substrates S is placed on the placement section 44. The placement section 44 is located in the lid open / close position. The lid 102 of the FOUP 100 has been removed from the FOUP body 101 by the door mechanism 42. The door body 50 is located in the open position (see FIG. 5( a)).

[0078] First, the LP control device 46 transmits information (schedule information) related to the schedule for imaging by the camera 61 to the controller 66. Information related to the imaging schedule includes, for example, the specifications of the FOUP 100, the number of substrates S that can be stored in the FOUP 100, the position of the uppermost slot among the multiple slots in the FOUP 100, and the set value for the descent speed of the door body 50. The schedule information is transmitted in advance to the LP control device 46 from, for example, a control unit (not shown) of the processing device 6. In addition to the schedule information, for example, a set value for the thickness of the substrates S (information for performing the double determination described below) is also transmitted in advance to the LP control device 46 from the control unit of the processing device 6. The controller 66 receives the schedule information from the LP control device 46. The controller 66 calculates an imaging schedule based on the schedule information (step S101 shown in FIG. 10 ). The imaging schedule is a timing schedule for determining how much time has elapsed since the controller 66 received a predetermined trigger signal and for the camera 61 to perform imaging. That is, the timing at which the first camera 63 captures the image of the imaging area 201 and the timing at which the second camera 64 captures the image of the imaging area 202 in order to detect each substrate S are set in advance.

[0079] As an example, the positioning of each imaging area related to imaging data for detecting substrate S1 (see Figures 8 and 9) will be described. The imaging area 201 (see Figure 8) when the first camera 63 is located at the first thickness position corresponds to the first imaging area of ​​the present invention. The imaging information obtained by imaging the first imaging area corresponds to the first imaging information of the present invention. The imaging area 202 (see Figure 8) when the second camera 64 is located at the first thickness position corresponds to the second imaging area of ​​the present invention. The imaging information obtained by imaging the second imaging area corresponds to the second imaging information of the present invention. The imaging area 201 (see Figure 9) when the first camera 63 is located at the second thickness position corresponds to the third imaging area of ​​the present invention. The imaging information obtained by imaging the third imaging area corresponds to the third imaging information of the present invention.

[0080] Next, the LP control device 46 controls the motor 58 of the door mechanism 42 to start lowering the scanner unit 45 together with the door main body 50 (and the door support unit 53) (step S102). At this time, the trigger sensor 65 detects the start of movement of the door support unit 53 and sends a detection signal to the controller 66. The controller 66 receives the detection signal as the trigger signal (step S103). Thereafter, the controller 66 causes each camera 61 to perform imaging based on the imaging schedule, for example, in the following manner.

[0081] The controller 66 first performs a first imaging (step S104). The first imaging is performed at a timing when a portion in the left-right direction of the board S accommodated in the uppermost slot of the plurality of slots is included in the plurality of determination regions 210. The controller 66 causes the first camera 63 to image the imaging region 201 and the second camera 64 to image the imaging region 202 at the above timing. In this manner, the first unit of imaging data is acquired. The controller 66 temporarily stores the acquired imaging data in, for example, a memory. The controller 66 may further store the imaging data in, for example, the above-mentioned internal storage (not shown).

[0082] Furthermore, the controller 66 sets to an initial value a counter for determining the substrates S accommodated in the FOUP 100 one by one in order from the top. More specifically, the controller 66 inputs, for example, 1 into a predetermined variable N (step S105).

[0083] Next, the controller 66 determines whether the timing for performing the (N+1)th imaging has arrived based on the imaging schedule (step S106). If the timing for performing the (N+1)th imaging has not arrived (step S106: No), the LP control device 46 continues to lower the scanner unit 45. If the timing for performing the (N+1)th imaging has arrived (step S106: Yes), the controller 66 controls the multiple cameras 61 to capture images of the imaging area 200 and acquire the (N+1)th unit of imaging data (step S107). This step of acquiring multiple units of imaging data (steps S104 and S107 combined) corresponds to the imaging information acquisition step of the present invention.

[0084] Next, the controller 66 performs accommodation determination to determine the accommodation state of the substrate S in the Nth slot from the top based on the plurality of determination data included in the Nth unit of image data and the (N+1)th unit of image data (determination step, step S108). Details will be described later.

[0085] Next, the controller 66 determines whether the determination process has been completed for all of the substrates S (step S109). If the controller 66 determines that there are still substrates S for which the determination process has not yet been performed (step S109: No), the controller 66 adds 1 to the variable N (step S110), for example, and returns to step S106. If the determination process has been completed for all of the substrates S (step S109: Yes), the controller 66 ends the mapping process.

[0086] (Determination Process) An example of the determination process for the storage state of each substrate S will be described with reference to Figures 11 to 12(d). Figure 11 is a flowchart showing the determination process for each substrate S. Figures 12(a) to 12(d) are diagrams for explaining the storage state of the substrate S. In summary, the controller 66 determines whether the storage state of the Nth substrate S is a double state or a cross state, whether the Nth substrate S is not present, or whether the Nth substrate S is stored normally.

[0087] In the following determination process, for convenience of explanation, the Nth unit of imaging data will be referred to as the first imaging data, and the (N+1)th unit of imaging data will be referred to as the second imaging data. The determination data for the determination regions 211, 212, and 213 in the first imaging data will be referred to as the first determination data, the second determination data, and the third determination data, respectively. The determination data for the determination regions 221, 222, and 223 in the second imaging data will be referred to as the fourth determination data, the fifth determination data, and the sixth determination data, respectively. Each of the first determination data, the second determination data, and the third determination data includes information about the substrate S and, for example, information about either the left side surface 113L or the right side surface 113R. The left side surface 113L and the right side surface 113R correspond to the first surface in this invention. Each of the fourth determination data, the fifth determination data, and the sixth determination data includes information about the substrate S and, for example, information about the top surface 113U. The top surface 113U corresponds to the second surface in this invention.

[0088] In this embodiment, there are two cases where the substrate S is easily detected based on the first to third determination data (first case), and where the substrate S is easily detected based on the fourth to sixth determination data (second case). The first case applies when the substrate S is a glass substrate that has not been subjected to edge treatment, for example, and the end face SE extends long in the vertical direction. The second case applies when the substrate S is a glass epoxy substrate, for example, or a glass substrate that has been subjected to edge treatment, and the end face SE is rounded.

[0089] First, the controller 66 determines whether the accommodation state of the Nth substrate S is a double state (double determination; step S201 shown in FIG. 11). The double state is a state in which two (or more) substrates S are accommodated vertically stacked in one slot, as shown in FIG. 12(a). The controller 66 detects the thickness of the substrate S based on each of the third determination data and the sixth determination data. The thickness detected based on the third determination data is referred to as the first thickness, and the thickness detected based on the sixth determination data is referred to as the second thickness. If at least one of the first thickness and the second thickness exceeds the set value for the thickness of one substrate S, the controller 66 determines that the accommodation state of the Nth substrate S is a double state (i.e., a double state is detected). If any other determination result is obtained, the controller 66 determines that the accommodation state of the Nth substrate S is not a double state.

[0090] When the double state is detected (step S202: Yes), the controller 66 stores information indicating that the accommodation state of the Nth substrate S is the double state in the memory (step S203). Then, the controller 66 ends the determination regarding the Nth substrate S.

[0091] When a double state is not detected (step S202: No), the controller 66 determines whether or not the storage state of the Nth substrate S is a cross state (cross determination). The cross state is a state in which part of the substrate S is placed on one of a pair of poles P lined up in the left-right direction, and another part of the substrate S is located below the pair of poles P, as shown in Figure 12(b) or 12(c), for example.

[0092] As a procedure for determining whether the Nth substrate S is in a cross state, the controller 66 first determines whether the substrate S is in a cross state based on, for example, low-magnification data (step S204). The controller 66 compares the vertical position of the substrate S detected based on the first determination data (hereinafter referred to as the first substrate position) with the vertical set position of the first pole P1 corresponding to the substrate S (hereinafter referred to as the first set position). The vertical set position of each pole P is, for example, the vertical position where the pole P is assumed to exist, which is pre-stored in the memory of the controller 66. Note that, because the position of each pole P has a design tolerance, there may be a difference between the designed vertical position of each pole P and its actual position. In this case, the controller 66 may detect the actual position of each pole P using, for example, pattern matching. For example, when the first substrate position is lower than the first set position, the controller 66 determines that the substrate S is in a cross state (i.e., a cross state is detected).

[0093] The controller 66 also makes a similar determination by comparing the vertical position of the substrate S detected based on the fourth determination data with the set vertical position of the first pole P1 corresponding to the substrate S.

[0094] The controller 66 also makes a similar determination by comparing the vertical position of the substrate S detected based on the second determination data with the vertical set position of the second pole P2 corresponding to the substrate S. The controller 66 also makes a similar determination by comparing the vertical position of the substrate S detected based on the fifth determination data with the vertical set position of the second pole P2 corresponding to the substrate S. In this way, the controller 66 makes multiple cross determinations.

[0095] When a cross state is detected in at least one of the cross determinations (step S205: Yes), the controller 66 stores information indicating that the accommodation state of the Nth substrate S is a cross state in memory (step S206).Then, the controller 66 ends the determination regarding the Nth substrate S.

[0096] When a cross state is not detected based on the low-magnification data (step S205: No), the controller 66 performs a cross determination taking into account the high-magnification data (step S207). The controller 66 compares the vertical position of the substrate S detected based on the third determination data with the vertical set position of the third pole P3 corresponding to that substrate S. This set position may be the same as the first set position in the vertical direction, or may be set independently of the first set position. When a cross state is detected (step S208: Yes), the controller 66 executes step S206 and ends the determination for the Nth substrate S.

[0097] When a cross state is not detected even when the high-magnification data is taken into consideration (step S208: No), the controller 66 determines whether or not the substrate S is present (step S209). More specifically, the controller 66 performs, for example, an A-judgment to determine whether or not the substrate S is present based on the first judgment data and a B-judgment to determine whether or not the substrate S is present based on the fourth judgment data. In this case, the first judgment data corresponds to the A-judgment information of the present invention. The fourth judgment data corresponds to the B-judgment information of the present invention. If the substrate S is not detected in either the A-judgment or the B-judgment, the controller 66 determines that the substrate S is not present, as shown in FIG. 9(d) (step S210: No). In this case, the controller 66 stores information indicating that the Nth substrate S is not present in memory (step S211). Then, the controller 66 ends the judgment regarding the Nth substrate S. On the other hand, if it is determined that the substrate S is present in at least one of the A-judgment and the B-judgment, the controller 66 determines that the Nth substrate S is present (i.e., correctly stored) (step S210: Yes). In this case, the controller 66 simply ends the judgment regarding the Nth substrate S. In this manner, the judgment process for the Nth substrate S is completed.

[0098] In step S209, the controller 66 may determine the presence or absence of the substrate S based on other determination data in addition to (or instead of) the first determination data and the fourth determination data. The controller 66 may, for example, perform determination A to determine the presence or absence of the substrate S based on the second determination data, and determination B to determine the presence or absence of the substrate S based on the fifth determination data. In addition to (or instead of) this, the controller 66 may, for example, perform determination A to determine the presence or absence of the substrate S based on the third determination data, and determination B to determine the presence or absence of the substrate S based on the sixth determination data.

[0099] As described above, the image capturing area 201 is captured by the first camera 63, and the image capturing area 202 is captured by the second camera 64. This not only allows for determination of the presence or absence of the substrate S, but also allows for various determinations (containment determinations) regarding whether the substrate S is properly contained within the FOUP 100. Furthermore, the first camera 63 captures images of the substrate S from multiple different positions in the vertical direction (thickness direction) (i.e., from multiple different angles). This increases the probability of obtaining determination information with a large difference in light intensity compared to when the presence or absence of the substrate S is detected based on only one piece of determination information. As a result, it increases the probability of detecting the substrate S properly. Therefore, regardless of the type of substrate S and / or the FOUP 100 (container), erroneous determinations regarding the containment status of the substrate S can be suppressed.

[0100] Furthermore, when it is determined that the substrate S is present in at least one of the A and B judgments, the controller 66 determines that the substrate S is present. In a situation where it is determined that the substrate S is present in at least one of the A and B judgments, the probability that the substrate S is present is extremely high. Therefore, the judgment in this embodiment is effective.

[0101] Furthermore, the plurality of pieces of determination information obtained by capturing images of the substrate S from different angles includes information on the inner wall surface 113 as the background of the substrate S. Because the inner wall surface 113 is generally flat, the light reflected from the inner wall surface 113 is weaker than the light reflected from special parts such as protrusions. Therefore, the probability of erroneous determination can be effectively reduced.

[0102] Next, a modified example of the embodiment will be described, with the same reference numerals being used to designate components having the same configuration as the embodiment, and the description thereof will be omitted as appropriate.

[0103] (1) The controller 66 may be capable of determining a cross state other than the cross state described in the above embodiment. For example, when a portion of a flexible board S is unintentionally placed below the pole P, the portion may sag significantly due to gravity and not be detected based on the determination data. The controller 66 may make a determination A based on each of the first determination data, the second determination data, and the third determination data. The controller 66 may make a determination B based on each of the fourth determination data, the fifth determination data, and the sixth determination data. In other words, the controller 66 may make a determination A and a determination B for three locations in the left-right direction of the board S. If the board S is not detected at one or two of the three locations, the controller 66 may determine that the storage state of the board S is a cross state.

[0104] (2) The arrangement of the multiple cameras 61 in the left-right direction is not limited to the above. That is, in the above-described embodiment, the left side surface 113L and the right side surface 113R correspond to the first surface of the present invention, and the top surface 113U corresponds to the second surface of the present invention. However, this is not limited to this. For example, the back surface 113B may also correspond to the first surface of the present invention. That is, the first surface is any one or more side surfaces of the multiple inner wall surfaces 113 that are arranged to partially surround the substrate S in the circumferential direction of the substrate S. Furthermore, for example, the bottom surface 113D may also correspond to the second surface of the present invention. That is, the second surface is a surface of the multiple inner wall surfaces 113 that is arranged on one side (upper or lower) in the thickness direction of the substrate S.

[0105] (3) In the above-described embodiments, the second camera 64 is capable of capturing images of multiple substrates S at once, just like the first camera 63. However, this is not limited to this. The second camera 64 may be configured so that only one substrate S fits in the imaging area 202. In other words, the second camera 64 does not have to be configured to acquire data for the above-described B judgment.

[0106] (4) In the above-described embodiments, the imaging unit has two cameras 61. However, this is not limited to this. The imaging unit may have three or more cameras 61. Some of the three or more cameras 61 may be arranged at different positions, for example, in the vertical direction. For example, a third camera (not shown) may be arranged above or below the first camera 63. With this configuration, the controller 66 may determine the accommodation state of the corresponding board S based on one unit of imaging data. In this case, the imaging area imaged by the third camera corresponds to the third imaging area of ​​the present invention. Alternatively, for example, a fourth camera (not shown) may be arranged above or below the second camera 64. The imaging area imaged by the fourth camera may correspond to the third imaging area of ​​the present invention.

[0107] (5) In the above-described embodiments, the multiple cameras 61 include a first camera 63 and a second camera 64 having different performance (e.g., at least one of resolution, magnification, and viewing angle). However, this is not limited to this. The multiple cameras 61 may include two cameras (not shown) having the same performance. One camera may capture images for cross determination. The other camera or both cameras may capture images for double determination. When double determination is performed based on image data acquired by both cameras, the accuracy of double determination can be further improved.

[0108] (6) In the above-described embodiments, one detection target point SP is set in each determination region 210. However, this is not limited to this. Multiple detection target points SP may be set in each determination region 210. Alternatively, the controller 66 may be configured to detect the entire region in each determination region 210 where light is specularly reflected as part of the end face SE.

[0109] (7) In the above-described embodiments, the front nodal point of the light-receiving lens 61a of the camera 61 is defined as the light-receiving point RP. However, this is not limited to this. The front principal point of the light-receiving lens 61a or a predetermined point on the front surface of the light-receiving lens 61a may also be defined as the light-receiving point RP. Alternatively, for example, if the front focal point of the light-receiving lens 61a is located inside the light-receiving lens 61a, the front focal point may also be defined as the light-receiving point RP. Alternatively, the rear principal point, the rear nodal point, or the like may also be defined as the light-receiving point RP.

[0110] (8) The number of poles P supporting each substrate S is not limited to three. The substrate S may be supported by a support member (not shown) separate from the pole P. Alternatively, both left and right ends of the substrate S may be supported by support portions (not shown) formed by cutting out the inner surface of the FOUP body 101, for example. The type of container is not limited to the FOUP 100. The present invention can also be applied to containers (not shown) other than the FOUP 100.

[0111] (9) The shape of the substrate S may be a shape other than a substantially rectangular shape when viewed from above. For example, the substrate S may be a substantially circular plate shape.

[0112] (10) In the above-described embodiments, the scanner unit 45 is fixed to, for example, the door body 50 (i.e., is driven by the motor 58 to move up and down integrally with the door body 50). However, this is not limited to this. The scanner unit 45 may be configured to be movable, for example, in the front-to-rear direction relative to the door body 50. Alternatively, the scanner unit 45 may be driven to move up and down independently of the door body 50 by a drive source (not shown) separate from the motor 58. Alternatively, the scanner unit 45 may be attached to the transport robot 3 or other structures within the EFEM 1.

[0113] (11) In the above-described embodiments, the controller 66 causes each camera 61 to capture images based on an image capture schedule. However, this is not limited to this. The controller 66 may cause each camera 61 to capture images while determining the vertical position of the scanner unit 45, for example. The vertical storage position of each board S may be stored in advance in the memory (RAM) of the controller 66, for example. The vertical position of the scanner unit 45 may be determined based on the number of steps of the motor 58, which is a stepping motor, for example. The controller 66 may cause each camera 61 to capture images when it determines that the vertical position of the scanner unit 45 has reached the vertical storage position of any board S.

[0114] (12) In the above-described embodiments, the LP control device 46 and the controller 66 are provided separately. However, this is not limited to this. For example, the LP control device 46 may be equipped with the controller 66. Alternatively, the LP control device 46 may have a function to control each camera 61 instead of the controller 66. When the LP control device 46 has such a function, the LP control device 46 corresponds to the determination unit of the present invention. Alternatively, for example, the control device 5 of the EFEM 1 may control the load port 4. In this case, the control device 5 corresponds to the determination unit of the present invention.

[0115] (13) The load port 4 may be mounted on equipment other than the EFEM 1.

[0116] (14) The present invention may be applied to mapping devices other than the load port 4.

[0117] DESCRIPTION OF SYMBOLS 4 Load port (mapping device) 58 Motor (driving unit) 61 Camera (imaging unit) 62 Lighting (light emitting unit) 63 First camera 64 Second camera 66 Controller (imaging information acquisition unit, determination unit) 100 FOUP (container) 102 Lid (lid body) 113 Inner wall surface 113B Back surface (first surface) 113D Bottom surface (second surface) 113L Left side surface (first surface) 113R Right side surface (first surface) 113U Top surface (second surface) 114 Opening 200 Imaging area 201 Imaging area (first imaging area, third imaging area) 202 Imaging area (second imaging area) S Substrate

Claims

1. A mapping device for detecting the storage state of a substrate stored in a container having an opening on a side, comprising: a light-emitting unit that emits light at least toward the inside of the container; an imaging unit that performs imaging by sensing reflected light of the light emitted from the light-emitting unit; a drive unit that drives the imaging unit to move in the thickness direction of the substrate; an imaging information acquisition unit that, with a lid for covering the opening removed from the container, causes the imaging unit to perform imaging while emitting light from the light-emitting unit while moving the imaging unit in the thickness direction using the drive unit, thereby acquiring multiple pieces of imaging information; and a determination unit that uses the multiple pieces of imaging information to make a storage determination as to whether the substrate is properly stored in the container, wherein the imaging unit has a first camera that is arranged at a first placement position in a predetermined intersecting direction that intersects with the thickness direction, and a second camera that is arranged at a second placement position in the intersecting direction that is different from the first placement position, and the multiple pieces of imaging information include first imaging information obtained by using the first camera to capture an image of a first imaging area that is preset to detect the substrate when the first camera is located at a first thickness position in the thickness direction, a mapping device comprising: second imaging information obtained by imaging a second imaging area, which is set in advance to detect the substrate and whose position in the intersecting direction is different from the first imaging area, with the second camera when the second camera is positioned at the first thickness position in the thickness direction; and third imaging information obtained by imaging a third imaging area, which is set in advance to detect the substrate, with the first camera when the first camera is positioned at a second thickness position different from the first thickness position in the thickness direction.

2. The mapping device described in claim 1, characterized in that the judgment unit performs judgment A to determine the presence or absence of the substrate based on the first imaging information, and judgment B to determine the presence or absence of the substrate based on the third imaging information, and determines that the substrate is present when it is determined that the substrate is present in at least one of judgment A and judgment B.

3. The mapping device described in claim 1 or 2, characterized in that the judgment unit uses A judgment information, which is part of the first imaging information, and B judgment information, which is part of the third imaging information, for the containment judgment, the A judgment information including information on the substrate and information on a first surface, which is one of one or more side surfaces among multiple inner wall surfaces contained in the container and which is arranged to partially surround the substrate in the circumferential direction of the substrate, and the B judgment information including information on the substrate and information on a second surface, which is one of the multiple inner wall surfaces and which is arranged on one side of the substrate in the thickness direction.

4. A mapping method for detecting the storage state of a substrate stored in a container having an opening on a side surface by using a mapping device, the mapping device comprising at least a light emitting unit that emits light toward the inside of the container, and an imaging unit that performs imaging by sensing reflected light emitted from the light emitting unit, the imaging unit having one or more cameras, and comprising: an imaging information acquisition step of acquiring multiple pieces of imaging information by causing the imaging unit to perform imaging while emitting light from the light emitting unit, with a lid for covering the opening being removed from the container; and a determination step of using the multiple pieces of imaging information to perform a storage determination as to whether the substrate is properly stored in the container, the multiple pieces of imaging information comprising: first imaging information obtained by using one of the one or more cameras to capture an image of a first imaging area that is preset to detect the substrate when the one camera is located at a first thickness position in the thickness direction of the substrate; a mapping method comprising: second imaging information obtained by imaging, with one of the one or more cameras, a second imaging area that is set in advance to detect the substrate and whose position in a predetermined intersecting direction that intersects the thickness direction is different from the first imaging area, when the one of the one or more cameras is located at the first thickness position in the thickness direction; and third imaging information obtained by imaging, with the one of the one or more cameras, a third imaging area that is set in advance to detect the substrate, when the one of the one or more cameras is located at a second thickness position that is different from the first thickness position in the thickness direction.

Images