Substrate transport device and method for determining abnormality of substrate transport device

Abstract

The present invention relates to a substrate transport device that detects abnormality in a plurality of end effectors and a method for determining abnormality in the substrate transport device, the substrate transport device includes a plurality of end effectors extending in a first direction and arranged in multiple stages in a second direction intersecting the first direction, each of which supports a substrate, a distance adjustment unit that adjusts a distance between the plurality of end effectors, and an abnormality detection unit that detects abnormality in the plurality of end effectors, and the plurality of end effectors may include a reference end effector whose position is fixed, and a variable end effector whose distance from the reference end effector is adjusted based on the reference end effector.

Description

[Technical field]

[0001] The present invention relates to a substrate transport apparatus and a method for determining an abnormality of the substrate transport apparatus, and more particularly to a substrate transport apparatus and a method for determining an abnormality of the substrate transport apparatus that detects abnormalities of a plurality of end effectors. [Background technology]

[0002] In order to perform a unit process in a semiconductor manufacturing process, a plurality of devices suited to the characteristics of each process are provided, and each of these different devices includes a substrate transport device for transporting a substrate such as a wafer.

[0003] Generally, a substrate transport device in a semiconductor facility serves to transport substrates from a load-lock chamber to a substrate receiving member (eg, a FOUP, a carrier, etc.) or from the substrate receiving member to the load-lock chamber.

[0004] In a batch-type substrate processing apparatus, a plurality of substrates are stacked in a substrate boat in a load lock chamber in a multi-tiered manner, and then a substrate processing process is performed on the plurality of substrates. In this case, in order to shorten the substrate transport time (e.g., loading time), the substrate transport apparatus has two or more end effectors, and can remove two or more substrates from a substrate accommodating member and load them collectively into the substrate boat.

[0005] Such substrate transport devices are susceptible to abnormalities such as slackness in the multiple end effectors. If an abnormality in the multiple end effectors causes a change in the spacing between the multiple end effectors, there is a risk of damage such as the substrate being scratched as it enters the substrate boat or substrate housing member, or of the substrate boat being pushed over and causing a major accident.

[0006] Therefore, in order to solve such problems, a technology is needed that can detect abnormalities such as loosening of the end effectors and determine abnormalities in the spacing between multiple end effectors. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Republic of Korea Publication Patent No. 10-2020-0130058 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention provides a substrate transport device and a method for determining an abnormality in the substrate transport device, which detects abnormalities in a plurality of end effectors, such as loose end effectors, to prevent substrate transport failure. [Means for solving the problem]

[0009] A substrate transport device according to one embodiment of the present invention includes a plurality of end effectors extending in a first direction and arranged in multiple stages in a second direction intersecting the first direction, each supporting a substrate, a spacing adjustment unit that adjusts the spacing between the plurality of end effectors, and an abnormality detection unit that detects abnormalities in the plurality of end effectors, and the plurality of end effectors may include a reference end effector whose position is fixed, and a variable end effector whose distance from the reference end effector is adjusted based on the reference end effector.

[0010] The abnormality sensing unit may include a light emitting unit and a light receiving unit, and the light emitting unit may include a plurality of light sources arranged in a number corresponding to the plurality of end effectors.

[0011] The plurality of light sources may be fixed at different positions in the second direction.

[0012] The plurality of light sources may include a first light source corresponding to the reference end effector, and a second light source disposed at a different position from the first light source in the second direction.

[0013] The second light source may be constituted by a plurality of light sources, and a distance between adjacent first light sources and the second light sources may be different from a distance between adjacent second light sources and the second light sources.

[0014] A distance between the adjacent first light source and the adjacent second light source may be equal to or greater than a minimum interval between the multiple end effectors and shorter than a distance between the adjacent second light source and the adjacent second light source.

[0015] The abnormality sensing unit may further include a light amount measuring unit that measures the amount of light received by the light receiving unit, and an abnormality judgment unit that judges an abnormality in the multiple end effectors based on the measured light amount.

[0016] The abnormality sensing unit may further include a criterion storage unit configured to store an amount of light received by the light receiving unit according to intervals between the plurality of end effectors.

[0017] The variable end effector may be configured in a plurality of parts, and the plurality of variable end effectors may be symmetrical with respect to the reference end effector.

[0018] According to another embodiment of the present invention, a method for determining an abnormality of a substrate transport device may include the steps of: storing an amount of light received by a light receiving unit of the abnormality detection unit from a light emitting unit of the abnormality detection unit for each interval between the multiple end effectors while adjusting the interval between the multiple end effectors, the end effectors having a reference end effector and a variable end effector; primarily measuring the amount of light received by the light receiving unit while the interval between the multiple end effectors is set to a first interval; comparing the amount of light at the first interval with the amount of light measured in the primary measuring step; secondarily measuring the amount of light received by the light receiving unit while the interval between the multiple end effectors is set to a second interval different from the first interval; and comparing the amount of light measured in the secondary measuring step with the amount of light at the second interval that is stored.

[0019] The stored amount of light at the second interval may be different from the stored amount of light at the first interval.

[0020] The second measuring step may be performed when a difference between the stored light amount at the first interval and the light amount measured in the first measuring step is within an allowable error range.

[0021] Furthermore, the method may further include a step of measuring the amount of light received by the light receiving unit while setting the interval between the multiple end effectors to an interval other than the first interval and the second interval, and comparing the amount of light received by the light receiving unit with the stored amount of light at the interval other than the first interval.

[0022] The light-emitting unit may include a plurality of light sources arranged in a number corresponding to the plurality of end effectors, and the first interval and the second interval may be determined according to positions of the plurality of light sources.

[0023] Light emitted from a first light source of the plurality of light sources corresponding to the reference end effector may be at least partially blocked by the reference end effector in a normal state.

[0024] The plurality of light sources may further include a second light source disposed at a position different from the first light source, and one or less of the variable end effectors may be located between adjacent first and second light sources.

[0025] The distance between the end effectors may be adjusted by driving a motor, and the method may further include storing motor encoder values ​​of the first distance and the second distance.

[0026] The variable end effector may be configured in a plurality of parts, and the plurality of variable end effectors may be symmetrical with respect to the reference end effector. Effect of the Invention

[0027] A substrate transport apparatus according to an embodiment of the present invention can detect abnormalities, such as loosening of multiple end effectors, through an abnormality detection unit, thereby identifying abnormalities in the end effectors before transporting a substrate, and can prevent damage to substrates and / or tipping of the substrate boat due to poor end effector transport.

[0028] In this case, the abnormality detection unit is equipped with a light-emitting unit and a light-receiving unit, and the light-emitting unit is equipped with a plurality of light sources arranged in a number corresponding to the plurality of end effectors, so that loosening can be effectively detected for each of the plurality of end effectors.

[0029] Also, the multiple light sources may include a first light source corresponding to a reference end effector and a second light source disposed at a position different from the first light source (in the second direction), and the first light source and the second light source may be fixed at positions different from each other (in the second direction). In this case, the first light source irradiates light (e.g., straight light) to the reference end effector in a normal state, and the light irradiated from the second light source is passed to the variable end effector as the interval between the multiple end effectors is adjusted via the interval adjustment unit, so that even when the interval between the multiple end effectors is adjusted via the interval adjustment unit, abnormalities in the multiple end effectors can be sensed without moving (or adjusting) the positions of the multiple light sources. [Brief description of the drawings]

[0030] [Figure 1] 1 is a schematic cross-sectional view showing a substrate transport apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating an abnormality sensing unit according to an embodiment of the present invention. [Diagram 3] FIG. 13 is a conceptual diagram for explaining abnormality detection of a plurality of end effectors according to an embodiment of the present invention. [Figure 4] FIG. 11 is a flowchart showing a method for determining an abnormality in a substrate transport device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, the embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various different forms. These embodiments are provided merely to complete the disclosure of the present invention and to fully inform those skilled in the art of the scope of the invention. In describing the present invention, the same reference numerals are used for the same components, and the drawings may be partially exaggerated in size to accurately describe the embodiments of the present invention, and the same numerals in the drawings indicate the same components.

[0032] FIG. 1 is a schematic cross-sectional view showing a substrate transfer device according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view for explaining an abnormality sensing unit according to an embodiment of the present invention.

[0033] Referring to Figures 1 and 2, a substrate transport device 100 according to one embodiment of the present invention may include a plurality of end effectors 110 extending in a first direction 11 and arranged in multiple stages in a second direction 12 intersecting the first direction 11, each supporting a substrate 10, a spacing adjustment unit 120 for adjusting the spacing between the plurality of end effectors 110, and abnormality detection units 130, 140 for detecting abnormalities in the plurality of end effectors 110.

[0034] A plurality of end-effectors 110 may extend in a first direction 11 and may be arranged (or stacked) in a second direction 12 intersecting the first direction 11 to form a multi-stage structure, and a substrate 10 may be supported on each stage (i.e., each of the plurality of end effectors). That is, two or more substrates 10 corresponding to the number of the plurality of end effectors 110 may be transported at once. Here, the first direction 11 may be a horizontal direction, and may be a front-back direction or a left-right direction, and the second direction 12 may be perpendicular to the first direction 11 and may be a vertical direction (or an up-down direction).

[0035] For example, the end effectors 110 may be in the shape of a fork having a plurality of fingers arranged (or aligned) in a third direction intersecting both the first direction 11 and the second direction 12 so as to be aligned with the first direction 11, and may contact the lower surface of the substrate 10 to support the substrate 10. Here, the third direction may be a direction intersecting the first direction 11 among the horizontal directions, or may be a left-right direction when the first direction 11 is a front-back direction, or may be a front-back direction when the first direction 11 is a left-right direction. The end effectors 110 may be made of quartz, aluminum oxide (Al 2 O 3), aluminum nitride (AlN), silicon carbide (SiC), titanium dioxide (TiO 2 ), silicon dioxide (SiO 2 In this case, the substrate 10 may be a wafer, but is not limited thereto, and may be a glass substrate or the like.

[0036] On the other hand, the end effectors 110 can be connected to each other on one side in the first direction 11 by the end effector hand 115, and each of the end effectors 110 can be fixed (or held) in a horizontal state. For example, the end effector hand 115 can be made of a material different from that of the end effectors 110, and can be made of a metal such as aluminum (Al), but is not particularly limited thereto. If the end effectors 110 and the end effector hand 115 are made of different materials, there is a risk that the end effectors 110 may crack or a bolt that connects each of the end effectors 110 to the end effector hand 115 may loosen, resulting in abnormal loosening (or abnormal loosening) of the end effectors 110.

[0037] The interval adjustment unit 120 can be connected to the multiple end effectors 110 and can adjust the intervals between the multiple end effectors 110. Here, the interval adjustment unit 120 can adjust the intervals between the multiple end effectors 110 in the second direction 12. For example, the interval adjustment unit 120 can be connected to the end effector hand 115 and can be connected to the multiple end effectors 110 and can adjust the intervals between the multiple end effectors 110 via the end effector hand 115. In this case, when the number of the multiple end effectors 110 is three or more, the intervals between any two adjacent end effectors 110 may be equal.

[0038] The loading interval of the substrates 10 in the substrate boat (not shown) may vary depending on the configuration (or structure) of the substrate boat (not shown) and / or the processing process of the substrates 10, and two or more substrates 10 can be stably loaded at once in accordance with various substrate boats (not shown) having different loading intervals of the substrates 10 via the interval adjustment unit 120.

[0039] In addition, the storage interval of the substrates 10 in a substrate storage member (not shown) such as a FOUP (Front Opening Unified Pod) or a carrier may be different from the loading interval of the substrates 10 in the substrate boat (not shown), and two or more substrates 10 may be removed from the substrate storage member (not shown) at once by adjusting the interval between the end effectors 110 to match the storage interval of the substrates 10 in the substrate storage member (not shown) via the interval adjustment unit 120. In addition, the two or more substrates 10 removed from the substrate storage member (not shown) may be loaded into the substrate boat (not shown) at once by adjusting the interval between the end effectors 110 to match the loading interval of the substrates 10 in the substrate boat (not shown).

[0040] Conversely, the processed substrates 10 can be removed from the substrate boat (not shown) in groups of two or more by adjusting the interval between the end effectors 110 via the interval adjustment unit 120 to match the loading interval of the substrates 10 in the substrate boat (not shown). The processed substrates 10 can be accommodated in the substrate accommodation member (not shown) by adjusting the interval between the end effectors 110 to match the accommodation interval of the substrates 10 in the substrate accommodation member (not shown).

[0041] Therefore, by adjusting the spacing between the multiple end effectors 110 via the spacing adjustment unit 120, it is possible to accommodate various substrate boats (not shown) having different loading intervals for the substrates 10, and it is also possible to accommodate cases where the storage interval for the substrates 10 in the substrate storage member (not shown) is different from the loading interval for the substrates 10 in the substrate boat (not shown).

[0042] The abnormality sensing units 130, 140 can sense abnormalities in the multiple end effectors 110, such as slack in the multiple end effectors 110. For example, the abnormality sensing units 130, 140 can sense slack in the multiple end effectors 110, and can confirm (or grasp) abnormalities in the multiple end effectors 110, such as poor transport.

[0043] If the end effector 110 becomes loose and tilts, the substrate 10 may slip, or when the substrate 10 is loaded onto a substrate boat (not shown), the substrate 10 may collide with a claw-like object (e.g., a partition plate, a substrate support tip, etc.) protruding from the inner surface of the substrate boat (not shown), resulting in damage to the substrate 10, such as scratches. In the worst case scenario, the loose (or tilted) end effector 110 may push the substrate boat (not shown) and cause it to tip over, which may result in a major accident.

[0044] However, the substrate transport apparatus 100 of the present invention can detect an abnormality, such as looseness, of the end effectors 110 before transporting the substrate 10 via the abnormality detectors 130, 140. This makes it possible to grasp the abnormality of the end effectors 110 and prevent damage to the substrate 10 and / or tipping over of the substrate boat (not shown) in advance.

[0045] Here, the multiple end effectors 110 may include a reference end effector 111 whose position is fixed, and a variable end effector 112 whose distance from the reference end effector 111 is adjusted based on the reference end effector 111. The position of the reference end effector 111 can be fixed, and the position in the second direction 12 can be fixed. In other words, the reference end effector 111 cannot move in the second direction 12, and the variable end effector 112 can move in the second direction 12 relative to the fixed reference end effector 111, thereby changing the distance between the multiple end effectors 110.

[0046] The distance between the variable end effector 112 and the reference end effector 111 can be adjusted based on the reference end effector 111, and the distance between the reference end effector 111 and the variable end effector 112 can be changed by moving the variable end effector 112 in the second direction 12 based on the reference end effector 111, and the spacing between the multiple end effectors 110 can be adjusted.

[0047] The substrate transport device 100 of the present invention detects abnormalities in the multiple end effectors 110, such as slackness of the multiple end effectors 110, through the abnormality detection units 130, 140, and can identify abnormalities in the multiple end effectors 110 before transporting the substrate 10, thereby preventing damage to the substrate 10 and / or tipping over of the substrate boat (not shown) due to poor transport of the multiple end effectors 110.

[0048] In this case, the abnormality sensing units 130, 140 may include a light emitting unit 130 and a light receiving unit 140. The light emitting unit 130 and the light receiving unit 140 may be arranged to face each other and in the third direction intersecting with the first direction 11 in which the end effector 110 extends. When detecting abnormalities in a plurality of end effectors 110, at least one end effector 110 may be located between the light emitting unit 130 and the light receiving unit 140.

[0049] For example, if the light-emitting unit 130 irradiates light (e.g., straight light) toward the light-receiving unit 140, it is possible to determine whether the end effectors 110 are loose or not depending on the state of reception of the light 31 by the light-receiving unit 140 (or the presence or absence of reception of the light). In general, the light-emitting unit 130 and the light-receiving unit 140 are located at the same height (or at the same position in the second direction) and can exchange horizontal light (i.e., the straight light). Here, the light 31 may be straight light or a thru-beam such as a laser beam or infrared ray (IR).

[0050] That is, the abnormality detectors 130 and 140 can detect loosening of the end effectors 110 by an optical sensing method via the light emitter 130 and the light receiver 140. For example, the abnormality detectors 130 and 140 can detect loosening of the end effectors 110 by a constant non-detection method for the end effectors 110 in which the light 31 is received by the light receiver 140 in a normal state and the light 31 is blocked by the end effector 110 in which loosening has occurred, and thus the light 31 is not received by the light receiver 140. Conversely, the abnormality detectors 130 and 140 can detect loosening of the end effectors 110 by a constant detection method for the end effectors 110 in which the light 31 is detected by the end effector 110 in a normal state and thus the light 31 is blocked by the end effector 110 and thus is not received by the light receiver 140, and thus the end effector 110 is loosened and thus the light 31 is received by the light receiver 140.

[0051] Therefore, in the present invention, by detecting looseness of the end effector 110 by optical detection via the light-emitting unit 130 and the light-receiving unit 140, abnormalities in a plurality of end effectors 110 can be effectively detected.

[0052] The light emitting unit 130 may include a plurality of light sources 131 arranged in a number corresponding to the plurality of end effectors 110. The plurality of light sources 131 may be arranged in a number corresponding to the plurality of end effectors 110, may be arranged in the same number as the plurality of end effectors 110, or may be arranged so that one light source corresponds to each of the plurality of end effectors 110, but is not particularly limited thereto.

[0053] For example, at least one light source 131 can be provided corresponding to each of the multiple end effectors 110. In this case, a light source 131 may be provided corresponding to each of the multiple end effectors 110, or one light source 131 may be provided corresponding to the reference end effector 111, and one or more (e.g., two) light sources 131 may be provided corresponding to the variable end effector 112. Here, the greatest number of light sources 131 may be provided corresponding to the variable end effector 112 that is the furthest from the reference end effector 111.

[0054] Furthermore, the multiple light sources 131 can emit (or irradiate) light 31, can irradiate the linear light, and may be optical fibers, lasers, or the like. In this case, the light receiving unit 140 can have a number of light receiving surfaces corresponding to the number of light sources 131 (for example, the same number), and can receive the light 31 irradiated from the multiple light sources 131 on one light receiving surface. In order to effectively detect slackness of each of the multiple end effectors 110, it may be preferable that the light receiving unit 140 has the light receiving surfaces corresponding to the multiple light sources 131, but is not particularly limited thereto.

[0055] Here, the abnormality sensing units 130, 140 can determine an abnormality in the spacing between the multiple end effectors 110 by sensing the looseness of the end effectors 110 through the constant sensing method using the multiple light sources 131. Also, the abnormality sensing units 130, 140 can determine an abnormality in the spacing between the multiple end effectors 110 by sensing the looseness of the end effectors 110 through the constant sensing method using the multiple light sources 131.

[0056] Therefore, it is possible to detect slackness of each of the multiple end effectors 110 and determine an abnormality in the spacing between the multiple end effectors 110, thereby preventing damage to the substrates 10 and / or tipping of the substrate boat (not shown) due to poor spacing between the multiple end effectors 110, while also allowing two or more substrates 10 to be stably loaded collectively on the substrate boat (not shown) having a set loading interval for the substrates 10. That is, by providing the light-emitting unit 130 with multiple light sources 131 arranged in a number corresponding to the multiple end effectors 110, it is possible to effectively detect slackness (or abnormality) in each of the multiple end effectors 110 and prevent damage to the substrates 10 and / or tipping of the substrate boat (not shown) due to poor spacing between the multiple end effectors 110.

[0057] At this time, the light sources 131 may be fixed at different positions in the second direction 12. In general, when adjusting the interval between the end effectors 110 via the interval adjuster 120, the positions of the light sources 131 are adjusted according to the interval between the end effectors 110, and looseness of each of the end effectors 110 corresponding to each of the light sources 131 is sensed. In this case, a separate component such as a position adjuster for adjusting the positions of the light sources 131 is required.

[0058] However, in the present invention, even when the interval between the multiple end effectors 110 is adjusted via the interval adjustment unit 120, the positions of the multiple light sources 131 in the second direction 12 can be suitably determined, and in a state in which the multiple light sources 131 are fixed at different positions in the second direction 12, the slack of the multiple end effectors 110 can be effectively detected without adjusting the positions of the multiple light sources 131, and the slack of each of the multiple end effectors 110 can be detected. This eliminates the need for a separate component such as the position adjustment unit, and the slack of each of the multiple end effectors 110 can be effectively detected without a separate component such as the position adjustment unit. In this case, the positions of the multiple light sources 131 in the second direction 12 can be suitably determined according to the number of the multiple end effectors 110, and the intervals between two adjacent light sources 131 may be the same (all), or at least one of the intervals between two adjacent light sources 131 may be different.

[0059] For example, the multiple light sources 131 may include a first light source 131a corresponding to the reference end effector 111 and a second light source 131b disposed at a position different from the first light source 131a in the second direction 12. The first light source 131a can be disposed corresponding to the reference end effector 111 and can sense loosening (or abnormality) of the reference end effector 111. Here, the first light source 131a can be fixed at the same position (or height) in the second direction 12 as the reference end effector 111, and the light 31 emitted from the first light source 131a can be at least partially blocked (or blocked) by the reference end effector 111 in a normal state. In this case, the position of the first light source 131a in the first direction 11 and / or the position in the third direction may be different from that of the reference end effector 111.

[0060] The second light source 131b can be disposed (or fixed) at a position in the second direction 12 different from the first light source 131a, and may be at a different position (or height) in the second direction 12 from the first light source 131a, so that an abnormality (or slackness) in the variable end effector 112 can be detected.

[0061] At this time, the light 31 irradiated from the second light source 131b can pass above (or through) or below (or through) the variable end effector 112 as the position of the variable end effector 112 changes (or moves) and be received by the light receiving unit 140, or be at least partially blocked (or obstructed) by the variable end effector 112.

[0062] For example, the light 31 irradiated from the second light source 131b positioned adjacent to the upper part (or lower part) of the first light source 131a can pass through the upper part (or lower part) of the variable end effector 112 positioned adjacent to the upper part (or lower part) of the reference end effector 111 at the minimum interval between the multiple end effectors 110 (or the minimum interval between the adjacent reference end effector and the variable end effector). And, the light 31 irradiated from the second light source 131b positioned adjacent to the upper part (or lower part) of the first light source 131a can pass through the lower part (or upper part) of the variable end effector 112 positioned adjacent to the upper part (or lower part) of the reference end effector 111 at the maximum interval between the multiple end effectors 110 (or the maximum interval between the adjacent reference end effector and the variable end effector). In addition, the light 31 irradiated from the second light source 131b located adjacent to the upper part (or lower part) of the first light source 131a can be blocked (or obstructed) by the variable end effector 112 located adjacent to the upper part (or lower part) of the reference end effector 111 at an intermediate distance between the minimum spacing and the maximum spacing of the multiple end effectors 110 (or an intermediate distance between the minimum spacing and the maximum spacing of adjacent reference end effectors and variable end effectors).

[0063] Here, the minimum interval between the multiple end effectors 110 may be a minimum interval adjustable by the interval adjustment unit 120, or may be the interval between the multiple end effectors 110 when the end effector hands 115 come into contact with each other and overlap. Meanwhile, the minimum interval between the multiple end effectors 110 may be greater than the thickness of the substrate 10 so that the (multiple) substrates 10 can be supported (in a multi-stage manner) between the multiple end effectors 110. And the maximum interval between the multiple end effectors 110 may be a maximum interval adjustable by the interval adjustment unit 120. For example, the maximum spacing between the multiple end effectors 110 may be smaller than the height of the substrate accommodating member (not shown) and / or the substrate boat (not shown), and may be the spacing at which adjacent reference end effectors 111 and variable end effectors 112 are farthest apart while (each) variable end effector 112 does not block the light 31 irradiated from the uncorresponding (or non-corresponding) second light source 131b.

[0064] At this time, the second light source 131b can be configured in a plurality of sources, and two or more may be provided in order to effectively detect the loosening (or abnormality) of the variable end effector 112. Alternatively, when the variable end effector 112 is multiple, a plurality of second light sources 131b may be provided corresponding to (or according to) the number of the variable end effectors 112. Through this, the loosening (or abnormality) of the variable end effector 112 corresponding to each second light source 131b can be effectively detected. That is, the loosening (or abnormality) of the corresponding variable end effector 112 can be detected through (a plurality of) second light sources 131b provided corresponding to each variable end effector 112, and the loosening (or abnormality) of the multiple end effectors 110 can be effectively detected together with the reference end effector 111 through the first light source 131a. In this case, at least one second light source 131b may be arranged corresponding to each variable end effector 112, and the number of second light sources 131b arranged corresponding to each variable end effector 112 may vary depending on the variable end effector 112 (e.g., depending on the position of the variable end effector).

[0065] The distance between the adjacent first light source 131a and second light source 131b may be different from the distance between the adjacent second light source 131b and second light source 131b. When the multiple light sources 131 are arranged at equal intervals (i.e., when the distance between the adjacent first light source and second light source and the distance between the adjacent second light source and second light source are the same), the intervals between the multiple end effectors 110 must always be aligned to a constant interval (or a predetermined interval) corresponding to the intervals between the multiple light sources 131 (for example, the same as the intervals between the multiple light sources), and then abnormalities in the multiple end effectors 110 must be sensed.

[0066] However, after the spacing between the multiple end effectors 110 has been adjusted by the spacing adjustment unit 120 so that it is different from the constant spacing, it is difficult to align the spacing between the multiple end effectors 110 accurately (or with high precision) to the constant spacing, and there is a risk of a slight (or minute) error in the constant spacing each time the spacing between the multiple end effectors 110 is aligned to the constant spacing.

[0067] When the amount of light received by the light receiving unit 140 is measured at an interval with an error from the fixed interval, there is a possibility that the amount of light received by the light receiving unit 140 measured at the fixed interval may differ from the amount of light received at the fixed interval. This makes it difficult to determine abnormalities in multiple end effectors 110, such as determining that multiple end effectors 110 are abnormal even if no slack occurs in the end effector 110, and reduces the accuracy (or precision) of abnormality determination. In addition, minute slack in the end effector 110 (for example, slackness less than the interval error from the fixed interval) cannot be detected due to an interval error from the fixed interval.

[0068] Therefore, the distance between adjacent first light source 131a and second light source 131b can be made different from the distance between adjacent second light source 131b and second light source 131b. In such a case, it is possible to determine abnormalities in a plurality of end effectors 110 at two or more (or multiple) intervals, and thus it is possible to sense even minute slackness in end effector 110 and determine abnormalities in the plurality of end effectors 110, improving the accuracy of abnormality determination in the plurality of end effectors 110.

[0069] For example, in the normal state (or under normal circumstances), the amount of light received by the light receiving unit 140 at an interval where only the light 31 irradiated from the first light source 131a is blocked by the reference end effector 111 (for example, the minimum interval or the maximum interval of the multiple end effectors) is primarily measured, and then the amount of light received by the light receiving unit 140 at at least one other interval is (secondarily) measured while increasing or decreasing the interval between the multiple end effectors 110. Here, the amount of light received by at least the light receiving unit 140 can be measured at an interval where not only the light 31 irradiated from the first light source 131a but also the light 31 irradiated from at least one second light source 131b is blocked by the variable end effector 112, and (each) variable end effector 112 can pass through (or pass by) the light 31 irradiated from the corresponding second light source 131b while increasing or decreasing the interval between the multiple end effectors 110. At this time, the time when each variable end effector 112 blocks the light 31 irradiated from the corresponding second light source 131b (i.e., the interval between the multiple end effectors) may differ depending on the distance (in the second direction) from the reference end effector 111.

[0070] Here, in the normal state, the amount of light received by the light receiving unit 140 can be measured at multiple intervals at which all the adjustable end effectors 112 can block the light 31 irradiated from the corresponding second light source 131b once each. Through this, when it is determined that the multiple end effectors 110 are abnormal, it is also possible to infer which of the multiple end effectors 110 has loosened (or become abnormal).

[0071] That is, in the present invention, in the normal state, the amount of light received by the light receiving unit 140 is measured multiple times (or at the multiple intervals) while increasing or decreasing the interval between the multiple end effectors 110 at the interval where only the light 31 irradiated from the first light source 131a is blocked by the reference end effector 111. This not only eliminates the difficulty in accurately aligning the constant intervals, but also improves the accuracy of abnormality determination for the multiple end effectors 110 and makes it possible to detect even slight slackness in the end effector 110.

[0072] On the other hand, the distance between the adjacent first light source 131a and second light source 131b may be equal to or greater than the minimum interval between the multiple end effectors 110, or may be shorter than the distance between the adjacent second light source 131b and second light source 131b. When the distance between the adjacent first light source 131a and second light source 131b is shorter than the minimum interval between the multiple end effectors 110, the interval between the multiple end effectors 110 in the normal state is adjusted so that the variable end effector 112 adjacent to the reference end effector 111 cannot block the light irradiated from the second light source 131b adjacent to the first light source 131a. In other words, if the distance between the adjacent first light source 131a and second light source 131b is shorter than the minimum spacing between the multiple end effectors 110, the variable end effector 112 adjacent to the reference end effector 111 cannot pass through the light irradiated from the second light source 131b adjacent to the first light source 131a, and as a result, accurate (or precise) abnormality detection (or loosening detection) of the variable end effector 112 adjacent to the reference end effector 111 cannot be performed.

[0073] For example, the second light source 131b adjacent to the first light source 131a at a distance shorter than the minimum interval of the multiple end effectors 110 can detect an abnormality of the variable end effector 112 adjacent to the reference end effector 111 only when the variable end effector 112 adjacent to the reference end effector 111 slackens under a specific condition (e.g., gradient). In other words, the second light source 131b adjacent to the first light source 131a at a distance shorter than the minimum interval of the multiple end effectors 110 will detect slack (or abnormality) of the reference end effector 111 so as to overlap with the role of the first light source 131a, or cannot detect an abnormality (or slack) of the variable end effector 112 adjacent to the lower part of the reference end effector 111.

[0074] Furthermore, when the distance between the adjacent first light source 131a and second light source 131b is equal to or greater than the distance between the adjacent second light source 131b and second light source 131b, even if the interval between the multiple end effectors 110 in the normal state is adjusted within the range of the minimum interval to the maximum interval, the variable end effector 112 adjacent to the reference end effector 111 cannot block the light irradiated from the second light source 131b adjacent to the first light source 131a, or the light irradiated from at least one second light source 131b such as the second light source 131b adjacent to the first light source 131a is blocked by two or more variable end effectors 112 due to the adjustment of the interval between the multiple end effectors 110. In such a case, it becomes impossible to accurately detect an abnormality (or looseness) of the multiple end effectors 110 such as the variable end effector 112 adjacent to the reference end effector 111.

[0075] For example, when the variable end effector 112 adjacent to the reference end effector 111 is unable to block the light irradiated from the second light source 131b adjacent to the first light source 131a, it is not possible to sense an abnormality (or looseness) in the variable end effector 112 adjacent to the reference end effector 111. Also, when the light irradiated from the at least one second light source 131b is blocked by the two or more variable end effectors 112, it becomes difficult to determine which variable end effector 112 has an abnormality (or looseness), and it becomes difficult to determine whether the light irradiated from the at least one second light source 131b has been blocked by the variable end effector 112 in the normal state or by the variable end effector 112 in which an abnormality (or looseness) has occurred.

[0076] Therefore, by making the distance between the adjacent first light source 131a and second light source 131b equal to or greater than the minimum interval between the end effectors 110 and shorter than the distance between the adjacent second light source 131b and second light source 131b, it is possible to accurately detect (or determine) an abnormality (or looseness) of each of the end effectors 110. In this case, it may be preferable that the distance between the adjacent first light source 131a and second light source 131b is greater than the minimum interval between the end effectors 110 so that the variable end effector 112 adjacent to the reference end effector 111 can pass the light irradiated from the second light source 131b adjacent to the first light source 131a from bottom to top (or from top to bottom) and eliminate the burden (or difficulty) of having to accurately align the intervals between the multiple end effectors 110 to the fixed interval.

[0077] That is, the substrate transport device 100 according to the present invention includes a first light source 131a corresponding to a reference end effector 111 and a second light source 131b disposed in a position different from the first light source 131a in the second direction 12, and the multiple light sources 131 are fixed at different positions in the second direction 12, so that the first light source 131a irradiates light to the reference end effector 111 in the normal state, and the variable end effector 112 can receive light 31 irradiated from the second light source 131b as the interval between the multiple end effectors 110 is adjusted via the interval adjustment unit 120. As a result, even when the interval between the multiple end effectors 110 is adjusted via the interval adjustment unit 120, abnormalities in the multiple end effectors 110 can be sensed without moving (or adjusting) the positions of the multiple light sources 131.

[0078] The abnormality sensing units 130 and 140 may further include a light amount measuring unit (not shown) that measures the amount of light received by the light receiving unit 140, and an abnormality determining unit (not shown) that determines an abnormality in the multiple end effectors 110 based on the measured amount of light. The light amount measuring unit (not shown) can measure the amount of light received by the light receiving unit 140, can measure the amount of light 31 irradiated from each light source 131, and can measure the total amount of light 31 irradiated from the multiple light sources 131. Meanwhile, the amount of light 31 irradiated from each light source 131 may vary depending on the distance from the first light source 131a with respect to the first light source 131a. This makes it possible to reliably infer which light source 131 has blocked the light 31 emitted from it, and it is also possible to (relatively) reduce the amount of light 31 emitted from the second light source 131b, which is the outermost and furthest from the first light source 131a from which the light 31 is almost (always) received by the light receiving unit 140, or to (relatively) reduce the amount of light 31 from the first light source 131a from which the light 31 is (always) blocked by the reference end effector 111 before an abnormality (or slackness) occurs in the reference end effector 111, thereby reducing power consumption due to the light emission from multiple light sources 131.

[0079] For example, the light amount measuring unit (not shown) can not only determine whether the light 31 is received by the light receiving unit 140 by on / off, but also check how much (or how much) of the light 31 is blocked by the end effector 110 due to slackness of the end effector 110. Meanwhile, the light amount measuring unit (not shown) can also grasp how many end effectors 110 have an abnormality based on the total amount of light received by the light receiving unit 140 when light 31 is irradiated from a plurality of light sources 131.

[0080] An abnormality determination unit (not shown) can determine an abnormality in the multiple end effectors 110 based on the amount of light measured by the light amount measurement unit (not shown), can determine slack in each of the multiple end effectors 110, and can determine an abnormality in the spacing between the multiple end effectors 110. At this time, when the amount of light measured by the light amount measurement unit (not shown) is different from the normal state (or the normal state) by a predetermined amount, it can be determined that the end effector 110 is loose and that the spacing between the multiple end effectors 110 is abnormal.

[0081] For example, when the light amount measured by the light amount measuring unit (not shown) is 100% different from the normal amount (i.e., when the light received by the light receiving unit is turned on / off), it can be determined that there is an abnormality in the spacing between the multiple end effectors 110 (or slackness of the end effectors), and when the light amount measured by the light amount measuring unit (not shown) is 50% different from the normal amount, it can be determined that there is an abnormality in the spacing between the multiple end effectors 110 (or slackness of the end effectors). Here, the predetermined amount may be set to a suitable amount that allows accurate determination of slackness of the end effector 110 (or abnormality in the spacing between the multiple end effectors).

[0082] In general, when the end effector 110 becomes loose (or when there is an abnormality in the spacing between the end effectors), the end effector 110 completely blocks or deviates from the light 31 irradiated from the light source 131, and there is a possibility that the end effector 110 may become loose slightly more or slightly less than the position of the light 31 irradiated from the light source 131 (or the position of the straight light) due to a slight error depending on the situation. When the end effector 110 becomes loose more or slightly less than the position of the light 31 irradiated from the light source 131, a part of the total amount of light 31 irradiated from the light source 131 can be received by the light receiving unit 140. In such a case, if slackness of the end effector 110 (or abnormal spacing between the multiple end effectors) is determined based solely on the on / off of the light 31 irradiated from the light source 131 (or the on / off of the light received by the light receiving unit), it will be impossible to determine that slight errors occurring depending on the situation are slackness of the end effector 110 (or abnormal spacing between the multiple end effectors).

[0083] Conversely, if even a slight change in the amount of light measured by the light amount measuring unit (not shown) is judged as a slackness of the end effector 110 (or an abnormality in the intervals between the multiple end effectors), even a slight slackness due to the load of the end effector 110 or a slight swing due to the movement of the end effector 110 may cause a slight change in the amount of light, and therefore even something that is not a slackness of the end effector 110 (or an abnormality in the intervals between the multiple end effectors) may be judged as a slackness of the end effector 110 (or an abnormality in the intervals between the multiple end effectors). As a result, when the amount of light measured by the light amount measuring unit (not shown) changes by 50% (i.e., 50% of the amount of light irradiated from the light source) or more, it may be preferable to judge as a slackness of the end effector 110 (or an abnormality in the intervals between the multiple end effectors), but this is not particularly limited thereto.

[0084] In addition, even if the end effector 110 is slightly loose, the substrate 10 may be transportable depending on the substrate 10 loading interval of the substrate boat (not shown) and / or the substrate 10 storage interval of the substrate storage member (not shown). For example, when the substrate 10 loading interval of the substrate boat (not shown) and / or the substrate 10 storage interval of the substrate storage member (not shown) are wide, the substrate 10 can be loaded and stored even if the end effector 110 is slightly loose, since there is no difficulty in loading or storing the substrate 10. However, when the substrate 10 loading interval of the substrate boat (not shown) and / or the substrate 10 storage interval of the substrate storage member (not shown) are narrow, even if the end effector 110 is slightly loose, the substrate 10 may be easily damaged, such as scratched, and therefore even a small amount of slack in the end effector 110 must be judged as an abnormality in the spacing between the multiple end effectors 110.

[0085] Therefore, the predetermined amount may be determined according to the interval at which the substrates 10 are loaded on the substrate boat (not shown) and / or the interval at which the substrates 10 are accommodated on the substrate accommodating member (not shown). For example, the predetermined amount is proportional to the interval at which the substrates 10 are loaded on the substrate boat (not shown) and / or the interval at which the substrates 10 are accommodated on the substrate accommodating member (not shown), and the predetermined amount becomes smaller as the interval at which the substrates 10 are loaded on the substrate boat (not shown) and / or the interval at which the substrates 10 are accommodated on the substrate accommodating member (not shown) becomes narrower, and becomes larger as the interval at which the substrates 10 are loaded on the substrate boat (not shown) and / or the interval at which the substrates 10 are accommodated on the substrate accommodating member (not shown) becomes wider.

[0086] Therefore, the abnormality detection units 130, 140 measure the amount of light received by the light receiving unit 140 through the light amount measuring unit (not shown) to determine abnormalities in the multiple end effectors 110 (e.g., slackness of the end effector or abnormal spacing between the multiple end effectors), thereby accurately determining whether or not the substrates 10 can be transported depending on the loading interval of the substrates 10 on the substrate boat (not shown) and / or the storage interval of the substrates 10 in the substrate storage member (not shown).

[0087] Meanwhile, maintenance of the end effector 110 can be determined according to the amount of light measured by the light amount measuring unit (not shown). The loosening of the end effector 110 may be caused by cracks in the end effector 110 made of a ceramic material or by loosening of bolts connecting the end effector 110 and the end effector hand 115, and the gradient (or angle) of the loosening may vary depending on the cause of the loosening. This allows the cause of the loosening to be inferred from the difference in the amount of light received by the light receiving unit 140 due to the difference in the gradient of the loosening. If the end effector 110 is cracked, the end effector 110 must be replaced, but if only the bolts are loosened, it is only necessary to tighten the bolts, so that the transportation of the substrate 10 can be stopped for a while to perform maintenance of the end effector 110. Furthermore, in the case where slack occurs due to the loosening of a bolt, the bolt will gradually loosen depending on the degree of loosening, so that after the gradient of loosening reaches a predetermined gradient (or a predetermined angle) or more, it can be decided to perform maintenance on the end effector 110, and the gradient of loosening can be obtained by calculation using the amount of light measured in the light amount measuring unit (not shown), for example.

[0088] The abnormality sensing units 130 and 140 may further include a criterion storage unit (not shown) for storing the amount of light received by the light receiving unit 140 according to the interval between the plurality of end effectors 110. The criterion storage unit (not shown) may store the amount of light received by the light receiving unit 140 according to the interval between the plurality of end effectors 110. In this case, the amount of light received by the light receiving unit 140 for each interval between the plurality of end effectors 110 may be measured in advance while changing the interval between the plurality of end effectors 110, and the amount of light received by the light receiving unit 140 according to the interval between the plurality of end effectors 110 may be stored (or updated) in the criterion storage unit (not shown) every time the amount of light received by the light receiving unit 140 at each interval between the plurality of end effectors 110 is measured.

[0089] If the amount of light received by the light receiving unit 140 for each interval between the multiple end effectors 110 is stored in a judgment criterion storage unit (not shown), an abnormality judgment unit (not shown) can compare the amount of light currently measured by the light amount measurement unit (not shown) with the amount of light received by the light receiving unit 140 at the measurement interval of the multiple end effectors 110 stored in the judgment criterion storage unit (not shown). Here, if there is a difference between the measured amount of light and the amount of light received by the light receiving unit 140 at the measurement interval, it can be judged that the multiple end effectors 110 are abnormal, and if the difference between the measured amount of light and the amount of light received by the light receiving unit 140 at the measurement interval falls outside the allowable error range, it can also be judged that the multiple end effectors 110 are abnormal. At this time, the amount of light can be measured at multiple (or two or more) (measurement) intervals, and the amount of light measured at each interval can be compared with the amount of light stored in the judgment criteria memory unit (not shown) (i.e., the amount of light received by the light receiving unit), making it possible to determine whether or not there is an abnormality in the multiple end effectors 110 for each interval.

[0090] The variable end effector 112 can be configured in multiple units. This allows three or more substrates 10 to be transported at once, further improving the efficiency of transporting the substrates 10. As the number of variable end effectors 112 increases, the arrangement of the multiple variable end effectors 112 becomes increasingly important.

[0091] Fig. 3 is a conceptual diagram for explaining anomaly detection of multiple end effectors according to one embodiment of the present invention, in which Fig. 3(a) shows measurement of the light amount at an initial interval (or maximum interval) of multiple end effectors, Fig. 3(b) shows measurement of the light amount at a second interval of multiple end effectors, Fig. 3(c) shows measurement of the light amount at a third interval of multiple end effectors, and Fig. 3(d) shows measurement of the light amount at a threshold interval (or minimum interval) of multiple end effectors. And Fig. 3(e) is a graph showing the amount of light received at the light receiving unit for each light amount measurement.

[0092] 3, the multiple variable end effectors 112 may be symmetrical with respect to the reference end effector 111, and may be symmetrically located (or disposed) on both sides (or above and below) of the reference end effector 111 in the second direction 12. When the multiple variable end effectors 112 are symmetrically located with respect to the reference end effector 111, a pair of variable end effectors 112 at the same distance from the reference end effector 111 is generated, and the number of the multiple intervals at which all the variable end effectors 112 can block the light 31 irradiated from the corresponding second light source 131b once in the normal state can be reduced, and can be reduced to half (i.e., half) of the multiple variable end effectors 112. In other words, the number of the multiple intervals at which the amount of light received by the light receiving unit 140 is measured can be minimized.

[0093] For example, as shown in Fig. 3, a total of five end effectors 110 may be configured with two adjustable end effectors 112 above and below the reference end effector 111 with the reference end effector 111 at the center, and the amount of light received by the light receiving unit 140 may be measured at four intervals. As shown in Fig. 3(a), at the maximum interval (or initial interval) of the multiple end effectors 110, only the light 31 irradiated from the first light source 131a may be blocked by the reference end effector 111 in the normal state, and the amount of light received by the light receiving unit 140 at the maximum interval (e.g., first interval) of the multiple end effectors 110 may be primarily measured. At this time, the light 31 irradiated from the second light source 131b above the first light source 131a may pass through the lower parts of the adjustable end effectors 112 above the reference end effector 111 and be received by the light receiving unit 140. In addition, the light 31 irradiated from the second light source 131 b below the first light source 131 a can pass through the upper parts of the movable end effectors 112 below the reference end effector 111 and be received by the light receiving unit 140 .

[0094] 3B, while decreasing the interval between the plurality of end effectors 110, the light 31 irradiated from the outermost second light source 131b in the normal state can also be measured secondarily at a second interval where the light 31 is blocked by a pair of movable end effectors 112 farthest (or outermost) from the reference end effector 111. At this time, the light 31 irradiated from the second light source 131b adjacent to the upper part of the first light source 131a can pass through the lower part of the movable end effector 112 adjacent to the upper part of the reference end effector 111 and be received by the light receiving unit 140. The light 31 irradiated from the second light source 131b adjacent to the lower part of the first light source 131a can pass through the upper part of the movable end effector 112 adjacent to the lower part of the reference end effector 111 and be received by the light receiving unit 140.

[0095] 3(c), while (further) decreasing the interval between the plurality of end effectors 110, the amount of light received by the light receiving unit 140 can be measured three-dimensionally at a third interval where the light 31 irradiated from the second light source 131b adjacent to the first light source 131a in the normal state is blocked by a pair of adjustable end effectors 112 adjacent to the reference end effector 111. At this time, the light 31 irradiated from the first light source 131a can be blocked by the reference end effector 111. And, the light 31 irradiated from the outermost second light source 131b above the first light source 131a can pass through the upper part of the uppermost adjustable end effector 112 and be received by the light receiving unit 140. Also, the light 31 irradiated from the outermost second light source 131 b below the first light source 131 a can pass through the lower part of the outermost lower variable end effector 112 and be received by the light receiving part 140 .

[0096] 3(d), the interval between the multiple end effectors 110 can be reduced to the minimum interval (or threshold interval) of the multiple end effectors 110, and only the light 31 irradiated from the first light source 131a can be blocked by the reference end effector 111 in the normal state at the minimum interval between the multiple end effectors 110, and the amount of light received by the light receiving unit 140 at the minimum interval (for example, a fourth interval) between the multiple end effectors 110 can be measured four-dimensionally. At this time, the light 31 irradiated from the second light source 131b above the first light source 131a can pass through the upper parts of the movable end effectors 112 above the reference end effector 111 and be received by the light receiving unit 140. The light 31 emitted from the second light source 131b below the first light source 131a can pass through the lower parts of the movable end effector 112 below the reference end effector 111 and be received by the light receiving unit 140.

[0097] FIG. 4 is a flowchart showing a method for determining an abnormality in a substrate transport device according to another embodiment of the present invention.

[0098] Referring to FIG. 4, a method for determining an abnormality of a substrate transport device according to another embodiment of the present invention will be described in more detail, but the overlapping parts with those described above in relation to the substrate transport device according to one embodiment of the present invention will be omitted.

[0099] According to another embodiment of the present invention, a method for determining an abnormality of a substrate transport device may include a step (S100) of storing an amount of light received by a light receiving unit of the abnormality detection unit from a light emitting unit of the abnormality detection unit for each interval between the end effectors while adjusting an interval between the end effectors, the end effectors having a reference end effector and a variable end effector; a step (S200) of primarily measuring the amount of light received by the light receiving unit with the interval between the end effectors set to a first interval; a step (S300) of comparing the amount of light at the first interval with the amount of light measured in the primary measuring step (S200); a step (S400) of secondarily measuring the amount of light received by the light receiving unit with the interval between the end effectors set to a second interval different from the first interval; and a step (S500) of comparing the amount of light at the second interval with the amount of light measured in the secondary measuring step (S400).

[0100] First, while adjusting the interval between a plurality of end effectors including a reference end effector and a variable end effector, the amount of light received by the light receiving unit of the abnormality detection unit from the light emitting unit of the abnormality detection unit is stored for each interval between the plurality of end effectors (S100). While adjusting the interval between the plurality of end effectors including a reference end effector and a variable end effector using a distance adjusting unit capable of adjusting the distance between the plurality of end effectors, the amount of light received by the light receiving unit of the abnormality detection unit from the light emitting unit of the abnormality detection unit can be stored in a judgment criterion storage unit for each interval between the plurality of end effectors. In this way, the amount of light received by the light receiving unit stored in the judgment criterion storage unit for each interval between the plurality of end effectors can be used to detect (or judge) an abnormality in the plurality of end effectors.

[0101] Here, the multiple end effectors may extend in a first direction and may include a reference end effector and a variable end effector, and the interval between them may be adjusted in a second direction intersecting the first direction by the interval adjustment unit. The reference end effector may be fixed in position, and its position in the second direction may be fixed. That is, the reference end effector may not move (or move up and down) in the second direction, and the variable end effector may move in the second direction relative to the fixed reference end effector, thereby changing the interval between the multiple end effectors.

[0102] The distance between the variable end effector and the reference end effector is adjustable based on the reference end effector, and the variable end effector can be moved in the second direction based on the reference end effector to change the distance between the reference end effector and the variable end effector, thereby adjusting the spacing between the multiple end effectors.

[0103] The determination criterion storage unit can store the amount of light received by the light receiving unit according to the interval between the multiple end effectors. At this time, the amount of light received by the light receiving unit for each interval between the multiple end effectors can be measured while changing the interval between the multiple end effectors in advance, and the amount of light received by the light receiving unit according to the interval between the multiple end effectors can be stored in the determination criterion storage unit, and the amount of light received by the light receiving unit according to the interval between the multiple end effectors can be stored (or updated) every time the amount of light received by the light receiving unit at each interval between the multiple end effectors is measured. At this time, the amount of light received by the light receiving unit according to the interval between the multiple end effectors in a normal state can be stored in the determination criterion storage unit.

[0104] Next, the amount of light received by the light receiving unit is primarily measured in a state where the interval between the end effectors is set to a first interval (S200). The amount of light received by the light receiving unit can be primarily measured in a light amount measuring unit of the abnormality detecting unit in a state where the interval between the end effectors is set to a first interval, and the primarily measured amount of light can be used to compare with the amount of light received by the light receiving unit at the first interval stored in the judgment criterion storage unit. For example, the amount of light received by the light receiving unit at the first interval can be (primarily) measured by adjusting the interval between the end effectors to the first interval via the interval adjusting unit. The light amount measuring unit can measure the amount of light received by the light receiving unit, and can also measure the amount of light irradiated from each light source of the light emitting unit, and can also measure the total amount of light irradiated from the multiple light sources.

[0105] For example, the light quantity measuring unit can check not only whether the light receiving unit receives light by turning on / off, but also how much (or how much) of light the end effector blocks due to slack in the end effector. Meanwhile, the light quantity measuring unit can also grasp how many of the end effectors have an abnormality based on the total amount of light received by the light receiving unit when light is irradiated from a plurality of the light sources.

[0106] Then, the stored light amount at the first interval is compared with the light amount measured in the primary measuring process (S200) (S300). The light amount at the first interval stored in the judgment criterion storage unit and the light amount measured in the primary measuring process (S200) can be compared in the abnormality judgment unit of the abnormality detection unit. For example, if there is a difference between the light amount received by the light receiving unit at the stored first interval and the light amount measured in the primary measuring process (S200), it can be judged that the end effectors are abnormal. Also, if the difference between the light amount received by the light receiving unit at the stored first interval and the light amount measured in the primary measuring process (S200) falls outside an allowable error range, it can be judged that the end effectors are abnormal. The abnormality determination unit can determine an abnormality in the end effectors based on the amount of light measured by the light amount measurement unit, can determine slack in each of the end effectors, and can determine an abnormality in the spacing between the end effectors. In this case, when the amount of light measured by the light amount measurement unit differs from the normal state (or the normal state) by a predetermined amount or more (for example, by an amount that deviates from the allowable error range), it can determine that the end effector is loose and that the spacing between the end effectors is abnormal.

[0107] For example, when the light amount measured by the light amount measuring unit is 100% different from normal (i.e., when the light received by the light receiving unit is turned on / off), it can be determined that there is an abnormality in the spacing between the multiple end effectors (or slack in the end effector), and when the light amount measured by the light amount measuring unit is 50% different from normal, it can be determined that there is an abnormality in the spacing between the multiple end effectors (or slack in the end effector).Here, the predetermined amount may be set to a suitable amount that allows accurate determination of slack in the end effector (or abnormality in the spacing between the multiple end effectors).

[0108] In general, when the end effector becomes loose (or when there is an abnormality in the spacing between the end effectors), the end effector completely blocks or deviates from the light irradiated from the light source, and there is a possibility that the end effector may become slightly more or slightly less loose than the position of the light irradiated from the light source (or the position of the straight light) due to a slight error depending on the situation. When the end effector becomes slightly more or slightly less loose than the position of the light irradiated from the light source, a part of the total amount of light irradiated from the light source may be received by the light receiving unit. In such a case, if slack in the end effector (or abnormal spacing between the multiple end effectors) is determined solely based on the on / off of the light irradiated from the light source (or the on / off of the light received by the light receiving unit), it will not be possible to determine that slight errors occur depending on the situation as slack in the end effector (or abnormal spacing between the multiple end effectors).

[0109] Conversely, if even a slight change in the amount of light measured by the light quantity measuring unit is judged to be a slackness of the end effector (or an abnormality in the intervals between the multiple end effectors), even slight changes in the amount of light may occur due to slight slackness caused by the load of the end effector or slight rocking caused by the movement of the end effector, so that even things that are not slackness of the end effector (or an abnormality in the intervals between the multiple end effectors) may be judged to be slackness of the end effector (or an abnormality in the intervals between the multiple end effectors). As a result, when the amount of light measured by the light quantity measuring unit changes by 50% (i.e., 50% of the amount of light irradiated from the light source) or more, it may be preferable to judge it to be slackness of the end effector (or an abnormality in the intervals between the multiple end effectors), but this is not particularly limited thereto.

[0110] Next, the amount of light received by the light receiving unit is measured secondarily in a state where the interval between the end effectors is set to a second interval different from the first interval (S400). The amount of light received by the light receiving unit can be measured secondarily in a state where the interval between the end effectors is set to a second interval different from the first interval. At this time, the amount of light received by the light receiving unit at the second interval can be measured (secondarily) by adjusting the interval between the end effectors to the second interval via the interval adjustment unit, and the secondarily measured amount of light can be used to compare with the amount of light received by the light receiving unit at the second interval stored in the judgment criterion storage unit. Here, the second interval may be different from the first interval.

[0111] Then, the stored light amount at the second interval is compared with the light amount measured in the secondary measuring process (S400) (S500). The light amount at the second interval stored in the judgment criterion storage unit can be compared with the light amount measured in the secondary measuring process (S400). For example, if there is a difference between the light amount received by the light receiving unit at the stored second interval and the light amount measured in the secondary measuring process (S400), it can be determined that the end effectors are abnormal. Also, if the difference between the light amount received by the light receiving unit at the stored second interval and the light amount measured in the secondary measuring process (S400) falls outside the allowable error range, it can be determined that the end effectors are abnormal.

[0112] As shown here, the abnormality determination unit can compare the amount of light currently measured by the light amount measurement unit with the amount of light received by the light receiving unit at the measurement intervals (e.g., the first interval and the second interval) of the multiple end effectors stored in the determination criterion storage unit. Here, the abnormality determination unit can determine that the multiple end effectors are abnormal when there is a difference between the measured amount of light and the amount of light received by the light receiving unit at the measurement interval. The abnormality determination unit can also determine that the multiple end effectors are abnormal when the difference between the measured amount of light and the amount of light received by the light receiving unit at the measurement interval falls outside the allowable error range. In this case, the light amount can be measured at least at the first interval and the second interval (i.e., two or more (measurement) intervals) and the measured amount of light at each interval can be compared with the amount of light stored in the determination criterion storage unit (i.e., the amount of light received by the light receiving unit), and the abnormality of the multiple end effectors can be determined for each interval.

[0113] Meanwhile, the step of storing the amount of light received by the light receiving unit for each interval between the end effectors (S100), the step of primarily measuring (S200), the step of comparing the amount of light measured in the step of primarily measuring (S200) (S300), the step of secondary measuring (S400), and the step of comparing the amount of light measured in the step of secondary measuring (S400) (S500) can be performed before (while the end effectors are not supporting the substrate) transporting (processing) of the substrate by supporting the substrate on the end effectors. Thus, the method of determining anomaly of the substrate transporting apparatus of the present invention can be used to determine anomaly of the substrate transporting apparatus, such as anomaly of the end effectors, and to start (or perform) the substrate transporting (processing) only if there is no anomaly of the end effectors.

[0114] Here, the stored amount of light at the second interval may be different from the stored amount of light at the first interval, i.e., the number (or the number of) of the light sources irradiating the light that will be blocked by the end effectors in the normal state at the first interval and the second interval may be different.

[0115] In other words, if the intervals between the multiple light sources are the same, it is not possible to determine (or detect) an abnormality in the multiple end effectors at multiple (or two or more) intervals, and therefore at least one of the intervals between the multiple light sources may be different from the other intervals. In such a case, the number (or number of) end effectors that block the light irradiated from each of the light sources at the first interval and the second interval, which are different from each other, may differ, and the amount of light at the stored first interval may differ from the amount of light at the stored second interval.

[0116] On the other hand, if the amount of light at the stored second interval is different from the amount of light at the stored first interval, the interval between the multiple end effectors can be grasped from the amount of light at each interval, and abnormalities in the multiple end effectors at each interval can be effectively determined, and it can be inferred which of the end effectors has an abnormality such as loosening.

[0117] The second measuring step (S400) may be performed when a difference between the stored light amount at the first interval and the light amount measured in the first measuring step (S200) is within an allowable error range. The second measuring step (S400) may be performed (only) when a difference between the stored light amount at the first interval and the light amount measured in the first measuring step (S200) is within an allowable error range. That is, when a difference between the stored light amount at the first interval and the light amount measured in the first measuring step (S200) deviates from the allowable error range, an abnormality such as loosening has already occurred in the end effectors, so that the second measuring step (S400) may not be performed and the substrate transport device, including the end effectors, may be maintained.

[0118] When at least one of the intervals between the multiple light sources is different from the others, it is possible to detect (or determine) slack (or abnormality) of only a portion of the end effectors of the multiple end effectors at the first interval. Therefore, when the difference between the stored light amount at the first interval and the light amount measured in the primary measurement process (S200) is within an allowable error range, the secondary measurement process (S400) can be performed to detect slack for the remaining end effectors for which no abnormality such as slack could be detected (or determined) at the first interval, and the amount of light received by the light receiving unit at the second interval can be measured (secondarily).

[0119] Meanwhile, even if the difference between the stored light amount at the first interval and the light amount measured in the primary measuring process (S200) is within the allowable error range, the secondary measuring process (S400) may be performed to detect slackness of the remaining end effectors in order to infer which of the end effectors has an abnormality such as slackness.

[0120] The method for determining an abnormality of a substrate transport device according to the present invention may further include a step (S600) of measuring an amount of light received by the light receiving unit while setting a distance between the plurality of end effectors to a distance other than the first distance and the second distance, and comparing the amount of light received by the light receiving unit with the stored amount of light at the distance other than the first distance and the second distance.

[0121] Furthermore, in a state where the intervals between the end effectors are set to an interval other than the first interval and the second interval, the amount of light received by the light receiving unit may be measured and compared with the amount of light at the other intervals stored (S600). If an abnormality (or looseness) cannot be detected for all of the end effectors through the primary measurement and the secondary measurement, the amount of light received by the light receiving unit may be further measured at an interval other than the first interval and the second interval, and the measured amount of light may be compared with the amount of light at the other intervals stored in the judgment criterion storage unit. In this case, the step of comparing the amount of light at the other intervals (S600) may be repeated (repeatedly performed) until an abnormality is detected for all of the end effectors, and may be repeated at different (or mutually different) intervals where the amount of light received by the light receiving unit is not measured in the step of measuring primarily (S200), the step of measuring secondary (S400), and the step of comparing the amount of light at the (previous) other intervals (S600). That is, in order to detect abnormalities in all of the multiple end effectors, the amount of light received by the light receiving unit can be measured at the first interval, the second interval, ..., the nth interval (e.g., the third interval, the fourth interval, etc.), and the measured amount of light can be compared with the amount of light at each interval stored in the judgment criterion memory unit, thereby making it possible to judge abnormalities in the multiple end effectors.

[0122] The light emitting unit may include a plurality of light sources arranged in a number corresponding to the plurality of end effectors. The plurality of light sources may be arranged in a number corresponding to the plurality of end effectors, may be arranged in the same number as the plurality of end effectors, or may be arranged so that one light source corresponds to each of the plurality of end effectors, but is not particularly limited thereto.

[0123] For example, at least one of the light sources may be provided corresponding to each of the end effectors, or one of the light sources may be provided corresponding to each of the end effectors, or one of the light sources may be provided corresponding to the reference end effector and one or more (e.g., two) of the light sources may be provided corresponding to the variable end effector. In this case, the greatest number of the light sources may be provided corresponding to the variable end effector that is furthest from the reference end effector.

[0124] Furthermore, the multiple light sources can emit (or irradiate) light, can irradiate linear light, and may be optical fibers, lasers, etc. In this case, the light receiving unit can have light receiving surfaces in a number corresponding to (for example, the same number as) the multiple light sources, and can receive light irradiated from the multiple light sources on one light receiving surface. In order to effectively detect slackness of each of the multiple end effectors, it may be preferable that the light receiving unit has the light receiving surfaces corresponding to the multiple light sources, but is not particularly limited thereto.

[0125] Here, the abnormality sensing unit may determine an abnormality in the spacing between the end effectors by sensing the loosening of the end effectors in a constant non-sensing manner using the plurality of light sources. Also, the abnormality sensing unit may determine an abnormality in the spacing between the end effectors by sensing the loosening of the end effectors in a constant sensing manner using the plurality of light sources.

[0126] Therefore, slackness of each of the multiple end effectors can be sensed to determine an abnormality in the spacing between the multiple end effectors, thereby preventing damage to the substrates and / or tipping of the substrate boat due to poor spacing between the multiple end effectors, while allowing two or more substrates to be stably loaded collectively in the substrate boat, which has a set substrate loading interval. That is, by providing the multiple light sources in the light-emitting unit that correspond in number to the multiple end effectors, slackness (or abnormality) can be effectively sensed for each of the multiple end effectors, and preventing damage to the substrates and / or tipping of the substrate boat due to poor spacing between the multiple end effectors.

[0127] In this case, the first interval and the second interval can be determined according to the positions of the plurality of light sources. The first interval and the second interval can be determined according to the positions of the plurality of light sources so that the number of the end effectors that block the light irradiated from each of the plurality of light sources at the first interval and the second interval differs. This makes it possible to sense (or determine) an abnormality (or looseness) of the plurality of end effectors at two or more (or multiple) intervals.

[0128] The light emitted from a first light source corresponding to the reference end effector among the plurality of light sources can be at least partially blocked by the reference end effector in a normal state. The first light source among the plurality of light sources can be disposed corresponding to the reference end effector, or can be fixed at the same position (or height) in the second direction as the reference end effector, and the light emitted from the first light source can be at least partially blocked (or blocked) by the reference end effector in a normal state. This makes it possible to sense loosening (or abnormality) of the reference end effector through the first light source, and when loosening occurs in the reference end effector and the amount of light received by the light receiving unit changes (for example, when the amount of light received by the light receiving unit increases), it can be determined that the reference end effector is abnormal (or loose).

[0129] The plurality of light sources may further include a second light source disposed at a different position from the first light source. The second light source may be disposed (or fixed) at a different position from the first light source in the second direction, may have a different position (or height) in the second direction from the first light source, and may be capable of sensing an abnormality (or slackness) of the variable end effector.

[0130] In this case, the light irradiated from the second light source can pass above (or above) or below (or below) the variable end effector as the position of the variable end effector changes (or moves) and be received by the light receiving unit, or can be at least partially blocked (or obstructed) by the variable end effector.

[0131] For example, the light irradiated from the second light source positioned adjacent to the upper part (or lower part) of the first light source can pass through the upper part (or lower part) of the variable end effector positioned adjacent to the upper part (or lower part) of the reference end effector at the minimum interval between the multiple end effectors (or the minimum interval between the adjacent reference end effector and the variable end effector). And, the light irradiated from the second light source positioned adjacent to the upper part (or lower part) of the first light source can pass through the lower part (or upper part) of the variable end effector positioned adjacent to the upper part (or lower part) of the reference end effector at the maximum interval between the multiple end effectors (or the maximum interval between the adjacent reference end effector and the variable end effector). In addition, light irradiated from the second light source located adjacent to the upper part (or lower part) of the first light source can be blocked (or obstructed) by the variable end effector located adjacent to the upper part (or lower part) of the reference end effector at an intermediate distance between the minimum spacing and the maximum spacing of the multiple end effectors (or an intermediate distance between the minimum spacing and the maximum spacing of adjacent reference end effectors and variable end effectors).

[0132] At this time, the second light source may be configured in a plurality of sources, and two or more may be arranged to effectively detect loosening (or abnormality) of the variable end effector, or when the variable end effector is multiple, a plurality of second light sources may be arranged corresponding to (or according to) the number of the variable end effectors. Through this, loosening (or abnormality) of the variable end effector corresponding to each of the second light sources can be effectively detected. That is, loosening (or abnormality) of the corresponding variable end effector can be detected through the (multiple) second light sources arranged corresponding to each of the variable end effectors, and loosening (or abnormality) of the multiple end effectors can be effectively detected together with the reference end effector using the first light source. At this time, at least one of the second light sources may be arranged corresponding to each of the variable end effectors, and the number of the second light sources arranged corresponding to each of the variable end effectors may vary depending on the variable end effector (for example, depending on the position of the variable end effector).

[0133] In addition, one or less of the variable end effectors may be located between the adjacent first light source and the adjacent second light source. In this case, the second light source adjacent to the first light source may detect (only) the corresponding one of the variable end effectors. Through this, the burden (or difficulty) of accurately aligning the intervals between the multiple end effectors to a constant interval (or a predetermined interval) may be eliminated by adjusting the intervals between the multiple end effectors so that the variable end effector adjacent to the reference end effector passes the light irradiated from the second light source adjacent to the first light source from bottom to top (or from top to bottom), and the abnormality (or looseness) of each of the multiple end effectors may be accurately detected (or determined).

[0134] For example, the distance between the adjacent first light source and the second light source can be different from the distance between the adjacent second light source and the second light source. When the multiple light sources are arranged at the same intervals (i.e., when the distance between the adjacent first light source and the second light source and the distance between the adjacent second light source and the second light source are the same), abnormalities in the multiple end effectors must be sensed after the intervals between the multiple end effectors are aligned to a predetermined interval (or the constant interval) corresponding to the intervals between the multiple light sources (e.g., the same as the intervals between the multiple light sources).

[0135] However, after the spacing adjustment unit adjusts the spacing between the multiple end effectors to be different from the specified spacing, it becomes difficult to align the spacing between the multiple end effectors accurately (or with high precision) to the specified spacing, and there is a risk of a slight (or tiny) error in the specified spacing each time the spacing between the multiple end effectors is aligned to the specified spacing.

[0136] When the amount of light received by the light receiving unit is measured at an interval with an error from the predetermined interval, there is a risk of a difference between the amount of light received by the light receiving unit measured at the predetermined interval. This makes it difficult to determine an abnormality in the multiple end effectors, such as determining that the multiple end effectors are abnormal even when there is no slack in the end effectors, and reduces the accuracy (or precision) of abnormality determination. In addition, a minute slack in the end effector (e.g., slackness less than the interval error from the predetermined interval) cannot be detected due to an error from the predetermined interval.

[0137] Therefore, the distance between the adjacent first light source and the second light source can be made different from the distance between the adjacent second light source and the second light source. In this case, it is possible to determine an abnormality in the multiple end effectors at two or more intervals, and thus it is possible to detect even a minute slack in the end effector and determine an abnormality in the multiple end effectors, improving the accuracy of determining an abnormality in the multiple end effectors.

[0138] In this case, in the normal state (or under normal circumstances), the amount of light received by the light receiving unit at an interval where only the light irradiated from the first light source is blocked by the reference end effector (for example, the minimum interval or the maximum interval of the multiple end effectors) can be primarily measured, and then the amount of light received by the light receiving unit at at least one other interval can be (secondarily) measured while increasing or decreasing the interval between the multiple end effectors. Here, the amount of light received by the light receiving unit at least at an interval where not only the light irradiated from the first light source but also the light irradiated from at least one of the second light sources is blocked by the variable end effector can be measured, and (each) of the variable end effectors can be made to pass through (or pass by) the light irradiated from the corresponding second light source while increasing or decreasing the interval between the multiple end effectors. In this case, the point at which each variable end effector blocks the light irradiated from the corresponding second light source (i.e., the spacing between the multiple end effectors) may differ depending on the distance (in the second direction) from the reference end effector.

[0139] Here, in the normal state, the amount of light received by the light receiving unit can be measured at multiple intervals at which all of the adjustable end effectors can block the light irradiated from the corresponding second light source at least once, and thus, when an abnormality is determined in the multiple end effectors, it can be inferred which of the multiple end effectors has loosened (or become abnormal).

[0140] In other words, in the present invention, by increasing or decreasing the distance between the multiple end effectors at the interval where only the light irradiated from the first light source is blocked by the reference end effector in the normal state, the amount of light received by the light receiving unit is measured multiple times (or at the multiple intervals), thereby not only eliminating the difficulty of accurately aligning the specified intervals, but also improving the accuracy of abnormality determination for the multiple end effectors and making it possible to detect even slight slackness in the end effector.

[0141] Also, the distance between the adjacent first light source and the second light source may be equal to or greater than the minimum interval between the multiple end effectors, or may be shorter than the distance between the adjacent second light source and the second light source. When the distance between the adjacent first light source and the second light source is shorter than the minimum interval between the multiple end effectors, the interval between the multiple end effectors in the normal state is adjusted so that the variable end effector adjacent to the reference end effector cannot block the light irradiated from the second light source adjacent to the first light source. When the distance between the adjacent first light source and the second light source is shorter than the minimum interval between the multiple end effectors, the variable end effector adjacent to the reference end effector cannot pass through the light irradiated from the second light source adjacent to the first light source, and therefore accurate (or precise) abnormality detection (or slack detection) of the variable end effector adjacent to the reference end effector cannot be performed.

[0142] That is, the second light source adjacent to the first light source at a distance shorter than the minimum interval of the multiple end effectors can detect an abnormality of the variable end effector adjacent to the reference end effector only when the variable end effector adjacent to the reference end effector slackens under a specific condition (e.g., gradient).The second light source adjacent to the first light source at a distance shorter than the minimum interval of the multiple end effectors cannot detect slack (or abnormality) of the reference end effector by overlapping with the role of the first light source, or cannot detect an abnormality (or slack) of the variable end effector adjacent to the lower part of the reference end effector.

[0143] Furthermore, when the distance between the adjacent first light source and the second light source is equal to or greater than the distance between the adjacent second light source and the second light source, even if the interval between the end effectors in the normal state is adjusted within the range of the minimum interval to the maximum interval, the variable end effector adjacent to the reference end effector may not be able to block the light emitted from the second light source adjacent to the first light source, or the light emitted from at least one of the second light sources such as the second light source adjacent to the first light source may be blocked by two or more of the variable end effectors due to the adjustment of the interval between the end effectors. In such a case, it becomes impossible to accurately detect an abnormality (or looseness) of the end effectors such as the variable end effector adjacent to the reference end effector.

[0144] As shown here, when the variable end effector adjacent to the reference end effector is unable to block the light irradiated from the second light source adjacent to the first light source, it is not possible to detect an abnormality (or looseness) in the variable end effector adjacent to the reference end effector. Also, when the light irradiated from the at least one second light source is blocked by the two or more variable end effectors, it becomes difficult to determine which of the variable end effectors has an abnormality (or looseness), and it becomes difficult to determine whether the light irradiated from the at least one second light source is blocked by the variable end effector in the normal state or the variable end effector in which an abnormality (or looseness) has occurred.

[0145] Therefore, by making the distance between the adjacent first light source and the second light source greater than or equal to the minimum spacing between the multiple end effectors and smaller than the distance between the adjacent second light source and the second light source, it is possible to accurately sense (or determine) abnormalities (or loosening) in each of the multiple end effectors.

[0146] On the other hand, the amount of light irradiated from each of the plurality of light sources may differ depending on the distance from the first light source to the first light source. This makes it possible to reliably estimate which of the light sources has been blocked, and to (relatively) reduce the amount of light irradiated from the second light source located at the outermost edge farthest from the first light source whose light (or irradiated light) is almost (always) received by the light receiving unit, or to (relatively) reduce the amount of light from the first light source whose light (or irradiated light) is (always) blocked by the reference end effector before an abnormality (or slackness) occurs in the reference end effector, thereby suppressing power consumption due to light emission from the plurality of light sources.

[0147] Here, the intervals between the end effectors may be adjusted by driving a motor. For example, the intervals between the end effectors may be adjusted by driving a motor, and an encoder value of the motor may differ (or change) depending on the intervals between the end effectors. Using this, in the step (S100) of storing the amount of light received by the light receiving unit for each interval between the end effectors, the amount of light received by the light receiving unit for each encoder value of the motor depending on the interval between the end effectors may be stored in the judgment criterion storage unit while adjusting the intervals between the end effectors.

[0148] In this case, the method for determining an abnormality in a substrate transport device according to the present invention may further include the step of storing motor encoder values ​​of the first interval and the second interval (S150).

[0149] The motor encoder values ​​of the first interval and the second interval can be stored (or recorded) (S150). The motor encoder values ​​of the first interval and the second interval can be stored in the judgment criterion storage unit. This allows the intervals between the end effectors to be adjusted (or adjusted) accurately (or precisely) and quickly to the first interval and / or the second interval using the motor encoder values ​​stored in the judgment criterion storage unit, thereby shortening the interval adjustment time for the end effectors and easily determining the detection. For example, the intervals between the end effectors can be adjusted (or adjusted) to the first interval by driving the motor to match (or adjust) the encoder value of the motor to the motor encoder value of the first interval. Also, the intervals between the end effectors can be adjusted to the second interval by driving the motor to match (or adjust) the encoder value of the motor to the motor encoder value of the second interval. On the other hand, motor encoder values ​​for intervals other than the above (e.g., the nth interval, such as the third interval, the fourth interval, etc.) can also be stored (or recorded), and the motor encoder values ​​for the other intervals can be used to accurately and quickly adjust the intervals between the multiple end effectors to the other intervals.

[0150] As shown here, by recording the motor encoder values ​​of the first interval, the second interval and / or other intervals, at which at least one of the end effectors will block the light emitted from each of the light sources, it is not necessary to precisely mount each of the multiple light sources at a predetermined (or determined) position, thereby reducing adjustment time and facilitating sensing judgment.

[0151] Here, the step of storing the motor encoder value (S150) may be performed before the step of primarily measuring (S200) and the step of secondly measuring (S400).

[0152] The variable end effector can be configured in a plurality of units. This allows three or more substrates to be transported at once, further improving the efficiency of transporting the substrates. As the number of the variable end effectors increases, the arrangement of the multiple variable end effectors becomes important.

[0153] The multiple variable end effectors may be symmetrical with respect to the reference end effector, and may be symmetrically located (or disposed) on both sides (or above and below) of the reference end effector in the second direction. When the multiple variable end effectors are symmetrically located with respect to the reference end effector, the variable end effectors are disposed at the same distance from the reference end effector in pairs, and the number of the multiple intervals may be reduced to half (i.e., half) of the multiple variable end effectors. In other words, the number of the multiple intervals for measuring the amount of light received by the light receiving unit may be minimized.

[0154] For example, the end effector may be configured with five end effectors in total, with two of the variable end effectors at the upper and lower parts of the reference end effector, and the amount of light received by the light receiving unit may be measured at four intervals. At the maximum interval (or initial interval) of the plurality of end effectors, only the light irradiated from the first light source may be blocked by the reference end effector in the normal state, and the amount of light received by the light receiving unit at the maximum interval (e.g., the first interval) of the plurality of end effectors may be primarily measured. At this time, the light irradiated from the second light source above the first light source may pass through the lower parts of each of the variable end effectors above the reference end effector and be received by the light receiving unit. Also, the light irradiated from the second light source below the first light source may pass through the upper parts of each of the variable end effectors below the reference end effector and be received by the light receiving unit.

[0155] Then, while reducing the interval between the plurality of end effectors, the light irradiated from the outermost second light source in the normal state can also be measured secondarily in terms of the amount of light received by the light receiving unit at the second interval where the light is blocked by the pair of movable end effectors farthest (or outermost) from the reference end effector. At this time, the light irradiated from the second light source adjacent to the upper part of the first light source can pass through the lower part of the movable end effector adjacent to the upper part of the reference end effector and be received by the light receiving unit. And the light irradiated from the second light source adjacent to the lower part of the first light source can pass through the upper part of the movable end effector adjacent to the lower part of the reference end effector and be received by the light receiving unit.

[0156] Also, while (further) decreasing the interval between the plurality of end effectors, the amount of light received by the light receiving unit can be tertiarily measured at a third interval where the light irradiated from the second light source adjacent to the first light source in the normal state is blocked by a pair of the variable end effectors adjacent to the reference end effector. At this time, the light irradiated from the first light source can be blocked by the reference end effector. And, the light irradiated from the second light source at the outermost portion above the first light source can pass through the upper portion of the upper outermost variable end effector and be received by the light receiving unit. And, the light irradiated from the second light source at the outermost portion below the first light source can pass through the lower portion of the lower outermost variable end effector and be received by the light receiving unit.

[0157] The interval between the end effectors may be reduced to a minimum interval (or threshold interval) between the end effectors, and only the light irradiated from the first light source may be blocked by the reference end effector in the normal state at the minimum interval between the end effectors, and the amount of light received by the light receiving unit at the minimum interval (e.g., a fourth interval) between the end effectors may be measured four-dimensionally. At this time, the light irradiated from the second light source above the first light source may pass through the upper parts of the movable end effectors above the reference end effector and be received by the light receiving unit. The light irradiated from the second light source below the first light source may pass through the lower parts of the movable end effectors below the reference end effector and be received by the light receiving unit.

[0158] In this way, in the present invention, by detecting an abnormality such as slackness of the multiple end effectors via the abnormality detection unit, it is possible to grasp the abnormality of the end effectors before transporting the substrates, and to prevent damage to the substrates and / or tipping over of the substrate boat due to poor transport by the end effectors. In this case, the abnormality detection unit includes a light-emitting unit and a light-receiving unit, and the light-emitting unit includes a number of light sources corresponding to the number of end effectors, so that slackness can be effectively detected for each of the multiple end effectors. In addition, the multiple light sources may include a first light source corresponding to a reference end effector and a second light source disposed at a position different from the first light source, and the first light source and the second light source may be fixed at different positions from each other. In such a case, a first light source irradiates light onto a reference end effector in a normal state, and by adjusting the spacing between the multiple end effectors using the spacing adjustment unit, light irradiated from a second light source is passed through the variable end effector, so that abnormalities in the multiple end effectors can be sensed without moving the positions of the multiple light sources, even when the spacing between the multiple end effectors is adjusted via the spacing adjustment unit.

[0159] Although the preferred embodiment of the present invention has been illustrated and described above, the present invention is not limited to the above embodiment, and it should be understood that various modifications can be made thereto and equivalent other embodiments can be adopted by those skilled in the art without departing from the gist of the present invention as claimed in the claims. Therefore, the technical scope of protection of the present invention should be determined by the appended claims.

Claims

1. a plurality of end effectors extending in a first direction and arranged in multiple stages in a second direction intersecting the first direction, each of which supports a substrate; a distance adjustment unit that adjusts distances between the plurality of end effectors; an abnormality detection unit that detects an abnormality in the plurality of end effectors; Equipped with The plurality of end effectors include a reference end effector whose position is fixed; a variable end effector whose distance to the reference end effector is adjusted based on the reference end effector; A substrate transport apparatus comprising:

2. The abnormality detection unit includes a light emitting unit and a light receiving unit. The substrate transport apparatus according to claim 1 , wherein the light emitting unit includes a plurality of light sources arranged in a number corresponding to the number of the end effectors.

3. The substrate transport apparatus according to claim 2 , wherein the plurality of light sources are fixed at positions different from one another in the second direction.

4. The plurality of light sources include a first light source corresponding to the reference end effector; a second light source disposed at a position different from the first light source in the second direction; The substrate transport apparatus of claim 2 .

5. The second light source is composed of a plurality of light sources, The substrate transport apparatus according to claim 4 , wherein a distance between adjacent first light sources and second light sources is different from a distance between adjacent second light sources and second light sources.

6. 6. The substrate transport apparatus of claim 5, wherein a distance between the adjacent first light source and the adjacent second light source is equal to or greater than a minimum spacing between the multiple end effectors and is shorter than a distance between the adjacent second light source and the adjacent second light source.

7. The abnormality detection unit is a light amount measuring unit for measuring an amount of light received by the light receiving unit; an abnormality determination unit that determines an abnormality of the plurality of end effectors based on the measured light amount; The substrate transport apparatus of claim 2 , further comprising:

8. The substrate transport apparatus according to claim 7 , wherein the abnormality sensing unit further comprises a criterion storage unit that stores an amount of light received by the light receiving unit according to intervals between the plurality of end effectors.

9. The variable end effector is composed of a plurality of The substrate transport apparatus of claim 1 , wherein the variable end effectors are symmetrical about the reference end effector.

10. a step of storing an amount of light received by a light receiving unit of the abnormality detection unit from a light emitting unit of the abnormality detection unit for each interval between the plurality of end effectors while adjusting an interval between the plurality of end effectors including a reference end effector and a variable end effector; a step of primarily measuring an amount of light received by the light receiving unit while a distance between the end effectors is set to a first distance; a step of comparing the stored amount of light at the first interval with the amount of light measured in the step of primarily measuring; a step of secondarily measuring an amount of light received by the light receiving unit while setting a distance between the plurality of end effectors to a second distance different from the first distance; a step of comparing the stored amount of light at the second interval with the amount of light measured in the step of secondly measuring; A method for determining an abnormality in a substrate transport device, comprising:

11. The method for determining an abnormality in a substrate transport device according to claim 10 , wherein the stored amount of light at the second interval is different from the stored amount of light at the first interval.

12. 11. The method of claim 10, wherein the second measuring process is performed when a difference between the stored light amount at the first interval and the light amount measured in the first measuring process is within an allowable error range.

13. The method for determining an abnormality in a substrate transport device according to claim 10, further comprising the step of measuring the amount of light received by the light receiving unit while setting the distance between the plurality of end effectors to a distance other than the first distance and the second distance, and comparing the amount of light received by the light receiving unit with the stored amount of light at the other distance.

14. The light emitting unit includes a plurality of light sources arranged in a number corresponding to the plurality of end effectors, The method for determining an abnormality in a substrate transport device according to claim 10 , wherein the first interval and the second interval are determined in accordance with positions of the plurality of light sources.

15. The method for determining an abnormality in a substrate transport device according to claim 14 , wherein light emitted from a first light source among the plurality of light sources corresponding to the reference end effector is at least partially blocked by the reference end effector in a normal state.

16. The plurality of light sources further includes a second light source disposed at a position different from the first light source, The method for determining an abnormality in a substrate transport device according to claim 15 , wherein one or less of the variable end effectors are located between the first light source and the second light source adjacent to each other.

17. The intervals between the plurality of end effectors are adjusted by driving a motor; The method of claim 14, further comprising the step of storing motor encoder values ​​of the first interval and the second interval.

18. The variable end effector is composed of a plurality of The method for determining an abnormality in a substrate transport device according to claim 10 , wherein the plurality of variable end effectors are symmetrical with respect to the reference end effector.

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