Substrate processing apparatus, control method, article manufacturing method and substrate processing procedure

Abstract

This invention relates to a substrate processing apparatus, a control method for the substrate processing apparatus, a method for manufacturing an article, and a program. The substrate processing apparatus for processing a substrate includes: an alignment unit that measures the positional deviation of the substrate and aligns the substrate based on the measurement; a transport system that transports the substrate; and a control unit that performs an evaluation process, wherein the evaluation process involves the alignment unit measuring the positional deviation of the substrate again after the substrate, aligned by the alignment unit, has been transported by the transport system through a predetermined path, and the control unit controls the transport system to transport the substrate based on the positional deviation obtained from the evaluation process.

Description

Technical Field

[0001] The present invention relates to a substrate processing device, a control method of the substrate processing device, an article manufacturing method and a program. Prior Art

[0002] In equipment used to manufacture items such as semiconductor devices and liquid crystal displays, substrates are transported by a transport mechanism. If the transport mechanism's holding force becomes insufficient while holding and transporting the substrate using a holding portion, the substrate is stopped and an operator is prompted to retrieve it. Examples of causes of insufficient holding force include contamination of the substrate's backside, substrate warping, deterioration of the transport mechanism, and abnormalities in vacuum suction pressure.

[0003] Patent Document 1 describes detecting the holding force of a holding portion that holds an object to be conveyed and selecting conveying characteristics corresponding to the holding force.

[0004] While the transport mechanism is holding and transporting a substrate with a holding portion, the substrate may move relative to the holding portion. In such cases, the substrate cannot be accurately transported to the target position, and transport errors such as collisions with other components may occur. [Prior Art Literature] [Patent Document] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-219390 Summary of the Invention

[0005] One aspect of the present invention provides techniques that facilitate reducing the occurrence of handling errors. A first aspect of the present invention relates to a substrate processing device for processing a substrate, the substrate processing device comprising: an alignment unit that measures a positional deviation of the substrate and aligns the substrate based on the measurement; a transport system that transports the substrate; and a control unit that performs an evaluation process, wherein the evaluation process is a process in which the alignment unit measures the positional deviation of the substrate after the substrate, which has been aligned by the alignment unit, is transported through a predetermined path by the transport system, and the control unit controls the transport of the substrate by the transport system based on the positional deviation obtained by the evaluation process. A second aspect of the present invention relates to a control method for a substrate processing device, wherein the substrate processing device comprises: an alignment portion that measures a position deviation of a substrate and aligns the substrate based on the measurement; and a transport system that transports the substrate. The control method comprises: a first step of controlling the alignment portion so as to align the substrate; a second step of, after the first step, controlling the transport system so as to transport the substrate through a predetermined path; a third step of, after the second step, controlling the alignment portion so as to measure the position deviation of the substrate; and a fourth step of controlling the transport system to transport the substrate based on the position deviation obtained in the third step. Simple diagram description

[0006] FIG. 1 is a plan view schematically showing the structure of a substrate processing apparatus according to one embodiment. [Fig. 2] is a diagram schematically showing a structural example of an exposure unit. [Fig. 3] is a diagram schematically showing the structure of a conveying mechanism. [Fig. 4A] is a schematic top view of an alignment portion. [ Fig. 4B ] is a schematic side view of the alignment portion. [Fig. 4C] is a schematic top view of the alignment portion. [Fig. 5] is a perspective view illustrating an open wafer cassette. FIG. 6 is a diagram illustrating the operation (control method) of the substrate processing apparatus according to the first embodiment. FIG. 7 is a diagram illustrating the operation (control method) of the substrate processing apparatus according to the second embodiment. FIG. 8 is a diagram illustrating an operation (control method) of the substrate processing apparatus according to the third embodiment. FIG. 9 is a diagram illustrating an operation (control method) of the substrate processing apparatus according to the fourth embodiment. Implementation Method

[0007] The following describes embodiments of the present invention based on the accompanying drawings. The following embodiments do not limit the scope of the claimed invention. While various features are described in the embodiments, the present invention is not limited to requiring all of these features, and any combination of features is possible. In the drawings, identical or similar components are denoted by the same reference numerals, and repeated descriptions are omitted.

[0008] In this specification and the drawings, basically, the vertical direction is defined as the Z axis, the horizontal plane perpendicular to the vertical direction is defined as the XY plane, and directions are expressed using an XYZ coordinate system in which axes are orthogonal to each other.

[0009] FIG1 is a top view schematically showing the structure of a substrate processing apparatus 1 according to one embodiment. The substrate processing apparatus 1 can be configured as an exposure apparatus that projects a pattern of an original onto a substrate using a projection optical system, thereby forming a pattern (latent image) on the substrate. The exposure apparatus is an example of a pattern forming apparatus or photolithography apparatus that forms or transfers a pattern on a substrate. The substrate processing apparatus 1 can also be configured as other types of pattern forming apparatuses or photolithography apparatuses. Examples of other types of pattern forming apparatuses or photolithography apparatuses include drawing apparatuses and imprinting apparatuses that use charged particle beams. The drawing apparatus can draw a pattern on a substrate using charged particle beams such as electron beams or ion beams. The imprinting apparatus uses a mold to shape an imprint on a substrate, thereby forming a pattern on the substrate. Alternatively, the substrate processing apparatus 1 can also be an ion bombardment apparatus, a developing apparatus, an etching apparatus, a film forming apparatus, an annealing apparatus, a sputtering apparatus, a vapor deposition apparatus, or a flattening apparatus. Alternatively, the substrate processing apparatus 1 can also be a transport apparatus that transports substrates to multiple transport destinations.

[0010] The substrate processing apparatus 1 may include a chamber 2, a pattern forming unit 4 housed in the chamber 2, and a transport system 3. The pattern forming unit 4 may include, for example, an exposure unit 20. The transport system 3 is configured to transport substrates to multiple transport destinations. The transport system 3 may include: a supply mechanism 5 for supplying substrates; an alignment unit 6; a carrier transfer port 7 for placing an open wafer cassette capable of accommodating multiple substrates; a transport mechanism 8 for transporting substrates; a substrate loading unit 9 for loading substrates; and a substrate unloading unit 10 for unloading substrates.

[0011] The alignment unit 6 can be configured to measure the alignment error of the substrate on which a pattern is to be formed in the pattern forming unit 4 and to align the substrate based on the measurement. For example, the alignment unit 6 can be configured as a pre-aligner. Alternatively, the carrier interface 7 can be configured to hold a sealed carrier instead of an open wafer box. The transport mechanism 8 and the supply mechanism 5 can include: a holding portion such as a gripper that holds the substrate; and a drive mechanism that moves the holding portion to transport the substrate. For example, the transport mechanism 8 can be a horizontal multi-jointed robot (SCARA robot). The substrate loading unit 9 can have a support portion 91 that supports the substrate from below, and the substrate unloading unit 10 can have a support portion 101 that supports the substrate from below.

[0012] The substrate processing apparatus 1 may further include a control unit 11. The control unit 11 may be configured to control the transport system 3 and the pattern forming unit 4. Alternatively, the control unit 11 may include a first control unit for controlling the transport system 3 and a second control unit for controlling the pattern forming unit 4. For example, the control unit 11 may be configured as a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), a general-purpose or dedicated computer with an embedded program, or a combination of all or part of these.

[0013] FIG2 schematically illustrates an example configuration of exposure unit 20. Exposure unit 20 can include: reticle (master) 21; reticle stage (master stage) 24, which holds reticle 21; illumination device 23; projection optical system 25; and substrate stage 26, which holds substrate 22. Exposure unit 20 can be configured to transfer the pattern of reticle 21 to substrate 22 using either a step-and-repeat method or a step-and-scan method.

[0014] The lighting device 23 includes a light source and an illumination optical system (not shown) to illuminate the reticle 21. As the light source, a pulse light source (laser), for example, can be used. Examples of usable lasers include ArF excimer lasers with a wavelength of approximately 193 nm and F2 excimer lasers with a wavelength of approximately 153 nm. However, the type of laser is not limited to excimer lasers; for example, YAG lasers can also be used, and the number of lasers is also not limited. In addition, when a laser is used as a light source, a beam shaping optical system that shapes the parallel beam from the laser light source into the desired beam shape and an incoherent optical system that incoheres the coherent laser can be provided. Furthermore, the light source that can be used is not limited to a pulse light source; one or more continuous light sources such as mercury lamps and xenon lamps can also be used. The illumination optical system includes lenses, reflectors, light integrators, apertures, and the like.

[0015] Reticle 21 is, for example, a master plate made of quartz glass, on which a pattern (e.g., a circuit pattern) to be transferred to a substrate is formed. Reticle stage 24 holds reticle 21 and is movable in the horizontal direction. Projection optical system 25 projects the pattern of reticle 21 illuminated by exposure light from lighting device 23 onto substrate 22 at a predetermined magnification (e.g., 1 / 4 or 1 / 5). As projection optical system 25, an optical system consisting only of a plurality of refractive lens elements, or an optical system (catadiorefractive optical system) consisting of a plurality of refractive lens elements and at least one concave mirror can be used. Alternatively, as projection optical system 25, an optical system including a plurality of refractive lens elements and at least one diffractive optical element such as a kinoform lens, or a total reflection mirror type optical system can also be used.

[0016] Substrate 22 is a substrate coated with photoresist. Furthermore, substrate stage 26 can be configured to hold substrate 22 and be movable at least horizontally. For example, when a step-and-scan method is employed, reticle stage 24 and substrate stage 26 can each move synchronously in the horizontal direction.

[0017] Next, the transport of the substrate 22 will be described. First, the resist-coated substrate 22 is loaded into the transport system 3. The loaded substrate 22 can be placed on a support portion 91 protruding from the upper surface of the table of the substrate loading section 9. The transport mechanism 8 can transport the substrate 22 from the substrate loading section 9 to the alignment section 6. The alignment section 6 adjusts the horizontal and rotational position of the substrate 22. The supply mechanism 5 can transport the substrate 22, aligned by the alignment section 6, to the substrate stage 26 of the exposure section 20. The substrate stage 26 can move along a horizontal plane and position the transported substrate 22 at a predetermined processing position. The drive mechanism for the substrate stage 26 can use, for example, a linear motor, electromagnetic actuator, or pulse motor (not shown). While this example illustrates the transport of the substrate 22 by the transport mechanism 8 and the supply mechanism 5, other transport mechanisms may also be provided. Furthermore, the transport destination of the substrate 22 may also include other transport destinations.

[0018] FIG3(a) is a top view schematically illustrating an example structure of the transport mechanism 8. FIG3(b) is a side view of the transport mechanism 8, viewed from the direction α shown in FIG3(a), as it attempts to retrieve the substrate 22 placed on the substrate loading section 9. The transport mechanism 8 can be configured to include a gripper (holding portion) 85 that holds the substrate 22, and the gripper 85 is driven to transport the substrate 22. The gripper 85 can have any shape that allows it to retrieve the substrate 22 and is not limited to the shape shown in FIG3(a). A suction port 86 for vacuum suctioning the substrate 22 can be provided on the upper surface of the gripper 85. The suction port 86 can be connected to a pressure reduction source 88, such as a vacuum pump, via a solenoid valve (not shown). The arrangement of the suction port 86 is not limited to the arrangement shown in FIG3(a) as long as it allows it to retain the substrate 22. For example, the suction port 86 can be arranged across the entire upper surface of the gripper 85, or a plurality of suction ports can be provided.

[0019] A sensor 89 for detecting pressure can be provided in the exhaust flow path connecting the reduced-pressure source 88 and the suction port 86. The exhaust flow path connecting the reduced-pressure source 88 and the suction port 86 communicates with the space between the substrate 22 and the gripping member 85. Therefore, by detecting the pressure in the exhaust flow path, it is possible to detect the pressure in the space between the substrate 22 and the gripping member 85, in other words, the suction force or holding force acting on the substrate 22. The sensor 89 only needs to be able to detect the pressure in the space between the substrate 22 and the gripping member 85. Therefore, the sensor 89 can also be configured to directly detect the pressure in the space between the substrate 22 and the gripping member 85.

[0020] The transport mechanism 8 can include multiple drive mechanisms for driving the gripper 85 along multiple axes, such as four axes (X-axis, Y-axis, Z-axis, and θZ-axis). Here, the θZ-axis represents rotation about the Z-axis. For example, the transport mechanism 8 can include a drive mechanism 81 for horizontal drive, a drive mechanism 82 for vertical drive, and drive mechanisms 83 and 84 for rotational drive (θZ-axis). The drive mechanism 82 for vertical drive, the drive mechanisms 83 and 84 for rotational drive, and the gripper 85 can each be connected by a drive shaft 87. The structure, number, and combination of the drive mechanisms are not limited to this example.

[0021] The substrate 22 can be placed on the support portion 91 protruding from the upper surface of the table of the substrate loading section 9. Under the control of the control section 11, after the gripper 85 is inserted into the space below the substrate 22, the gripper 85 is driven upward. The air in the space below the substrate 22 is sucked in by the suction port 86, allowing the substrate 22 to be held by the gripper 85 by vacuum suction. The support section 91 is then driven downward, transferring the substrate 22 from the support section 91 to the gripper 85. The gripper 85 holds the substrate 22 by vacuum suction, thereby preventing positional deviation of the substrate 22 during transport. The substrate 22 contacts the upper surface of the gripper 85, blocking the suction port 86 with the substrate 22. This causes the pressure in the exhaust flow path to change to a negative pressure relative to atmospheric pressure. By detecting this change in the pressure in the exhaust flow path with the sensor 89, the control section 11 can detect that the substrate 22 is being held by the gripper 85 by vacuum suction. The pressure detected by the sensor 89 can be the suction pressure. The suction pressure is correlated with the holding force of the gripper 85 for holding the substrate 22 , so detecting the suction pressure can thereby detect the holding force.

[0022] Figures 4A and 4B are schematic top and side views, respectively, of the alignment unit 6. For example, the alignment unit 6 can include: a support unit 62 that supports the substrate 22; a drive unit 63 that drives the support unit 62; a plurality of sensors 64 to 66; and an alignment stage 67. For example, the drive unit 63 can include: a mechanism for rotating the support unit 62 about an axis parallel to the Z axis; and a mechanism for horizontally moving the support unit 62 in at least one direction within the XY plane (typically the X and Y directions). Alternatively, the drive unit 63 can include a mechanism for moving the support unit 62 in a direction parallel to the Z axis, i.e., a lifting mechanism. The support unit 62 and the drive unit 63 can constitute a movable stage mechanism in the alignment unit 6. The plurality of sensors 64 to 66 can be supported by a support structure (e.g., a plate-like member) (not shown), thereby enabling detection of the edge position of the substrate 22 from above.

[0023] The alignment unit 6 can include multiple light irradiation units 61. For example, the multiple light irradiation units 61 can be supported by an alignment stage 67 and irradiate light toward the substrate 22. The multiple light irradiation units 61 can be arranged so as to face the multiple sensors 64 to 66 across the edge of the substrate 22. The multiple sensors 64 to 66 can detect the edge position of the substrate 22 based on the boundary position between the area where light from the light irradiation units 61 is blocked by the substrate 22 and the area where light is not blocked, and provide the detection result to the control unit 11 via wired or wireless communication.

[0024] Sensors 64 in a plurality of sensors 64 to 66 are capable of detecting the position of the notch or positioning side provided at the substrate 22, i.e., the rotation angle (θ) of the axis (θZ axis) parallel to the Z-axis of the substrate 22 during the period when the substrate 22 is rotated once by the drive portion 63 . The following, when referred to as the angle of rotation, refers to the angle of rotation about the θZ axis. The drive 63 is capable of detecting the position of the notch or positioning side by the sensor 64 in such a way that the notch or positioning side is located on the lower side of the sensor 64 , and based on its detection results, the base plate 22 is rotated in such a way that the rotation angle of the base plate 22 is consistent with the appropriate rotation angle. The appropriate rotation angle can be a rotation angle preset by the user.

[0025] As illustrated in Figure 4A , the notch is a notation made by cutting a part of the substrate 22 into a V shape, capable of detecting the rotation angle of the substrate 22 by detecting the position of the notch. On the other hand, the positioning edge is short for Orientation Flat and is a notation in which a part of the substrate 22 is cut in a straight line. The rotation angle of the substrate 22 is able to be detected by detecting the position of the positioning edge. In the case of substrate 22 as a small diameter The size of the notch as a notation when the notch is provided is reduced relatively in conjunction with the size of the substrate 22 , thus the rotation angle cannot be detected accurately. Thereby, the positioning edge is preferably set up in the case where the substrate 22 is the path. On the other hand, in the case of a large diameter of the substrate 22 when the positioning edge is set up the area cut on the substrate 22 increases for notation. Thereby, a notch is preferably set up in the case where the substrate 22 is of large diameter.

[0026] For example, sensor 65 as well as sensor 66 are line sensors with multiple photoelectric transforming elements arranged in a linear manner capable of detecting the position of the substrate 22 in the XY plane based on these outputs. Sensors 65 as well as sensors 66 are configured in such a way that the orientation of the arrangement of multiple photoelectric transform elements (directions with resolution forces) is mutually orthogonal, separately for the distances from the edge of the substrate 22 to the center of the sensor (center of the sensor). When light is illuminated from the light irradiation portion 61 toward the substrate 22 , the light is blocked by the substrate 22 . Sensor 65 as well as sensor 66 performs detection for the distance from the edge of the substrate 22 to the center of the sensor. The arrow symbols shown in Fig. 4A indicate the distance from the edge of the substrate 22 to the center of the sensor. On the other hand, in the example of FIG. 4C , the substrate 22 is offset in the positive direction toward the X-axis so that the distance from the edge to the center of the sensor detected by the sensor 65 is greater than the distance from the edge to the center of the sensor detected by the sensor 66 .

[0027] The position (X) of the substrate 22 in the X-axis direction can be detected based on the distance from the edge to the sensor center detected by sensor 65 and the distance from the edge to the sensor center detected by sensor 66. As in the example shown in FIG4A , if the distance detected by sensor 65 and the distance detected by sensor 66 are the same, the substrate 22 is in the appropriate position in the X-axis direction. On the other hand, if the distance detected by sensor 65 and the distance detected by sensor 66 are different, as in FIG4C , the substrate 22 is not in the appropriate position in the X-axis direction.

[0028] If the substrate 22 has a positioning edge, the Y-axis position (Y) of the substrate 22 can be detected based on the distance from the edge to the sensor center detected by sensor 65 and the distance from the edge to the sensor center detected by sensor 66. Furthermore, if the distance from the edge to the sensor center detected by sensor 65 and the distance from the edge to the sensor center detected by sensor 66 are predetermined distances set by the user, the substrate 22 is properly positioned in the Y-axis direction. If the substrate 22 has a notch, the Y-axis position (Y) of the substrate 22 can be detected by sensor 64 by measuring the length of the width of the V-shaped notch. If the width of the notch at the predetermined position is the predetermined length set by the user, the substrate 22 is properly positioned in the Y-axis direction. In this way, multiple sensors 64 to 66 can be used to detect the position of the substrate 22 on the XY plane (horizontal direction).

[0029] The control unit 11 drives the drive unit 63 based on the detection results of the multiple sensors 64 to 66, that is, the position information (X, Y, θ) of the substrate 22, to move the substrate 22 to the appropriate position. Properly positioning the substrate 22 reduces the time required for alignment of the exposure unit 20. The multiple sensors 64 to 66 can be composed of line sensors or area sensors. As long as they can obtain the position information (X, Y, θ) of the substrate 22, the type and number of sensors are not limited to a specific type or number.

[0030] Based on the detection results obtained using the multiple sensors 64 to 66, the control unit 11 can obtain the amount of deviation (from the proper position) in the position (X, Y, θ) of the substrate 22 supported by the support unit 62, i.e., the alignment error. Furthermore, the control unit 11 causes the drive unit 63 to drive the support unit 62 to correct the deviation in the position of the substrate 22, thereby aligning the position of the substrate 22 with the proper position. Here, the alignment error (from the proper position) detected using the multiple sensors 64 to 66 is synonymous with the amount of correction to be applied to the position of the substrate 22.

[0031] Figure 5 is a perspective view illustrating an open wafer cassette 71 placed on the carrier transfer port 7. The open wafer cassette 71 can include a pair of side walls 710 extending in a vertical direction; a bottom wall 711 connected to the lower ends of the pair of side walls 710; and a top wall 712 facing the bottom wall 711 and connected to the upper ends of the pair of side walls. The side walls 710 are provided with a plurality of slots 710a for accommodating substrates 22 at predetermined intervals. A front opening 713 is provided on the front surface of the open wafer cassette 71, allowing the entry and exit of substrates 22. A rear opening 714 is provided on the rear surface, facing the front opening 713. The width of the rear opening 714 in the left-right direction is narrower than that of the front opening 713 to prevent the entry and exit of substrates 22. In other words, the width of the rear opening 714 is smaller than the outer diameter of the substrate 22.

[0032] The following describes the operation (control method) of the substrate processing apparatus 1 according to the first embodiment by way of example with reference to FIG6 . The operation shown in FIG6 is controlled by the control unit 11 . In step S602 , the substrate 22 is loaded into the substrate loading unit 9 . Then, in step S603 , the holding force of the transport system 3 on the substrate 22 is detected. For example, the holding force of the transport system 3 on the substrate 22 can be detected by detecting the pressure by the sensor 89 while the substrate 22 is being held by the gripper 85 of the transport mechanism 8 . Alternatively, the holding force of the transport system 3 on the substrate 22 can be detected by detecting the pressure of a suction line (not shown) provided on the support unit 91 by a sensor (not shown) immediately after the substrate 22 is loaded into the substrate loading unit 9 .

[0033] Next, in step S604, the transport mechanism 8 transports the substrate 22 to the alignment unit 6. Then, in step S605, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement. Then, in step S606, the control unit 11 determines whether the holding force for the substrate 22 detected in step S603 is greater than a specified value. If the holding force for the substrate 22 is determined to be greater than the specified value, the control unit 11 proceeds to step S607; if the holding force for the substrate 22 is determined to be less than the specified value, the control unit 11 proceeds to step S611. A holding force for the substrate 22 greater than the specified value indicates that the supply mechanism 5 can transport the substrate 22 to the pattern forming unit 4. A holding force for the substrate 22 less than the specified value indicates that a problem may occur when the supply mechanism 5 transports the substrate 22 to the pattern forming unit 4. For example, the prescribed value can be pre-set in such a manner as to ensure that the holding force on the substrate 22 detected in step S603 will be less than the prescribed value when the back surface of the substrate 22 is contaminated or the substrate 22 has warpage exceeding an allowable limit.

[0034] In step S607 , the substrate 22 is conveyed to the pattern forming section 4 by the supply mechanism 5 . In step S608 , the substrate 22 is exposed in the pattern forming section 4 . In step S609 , the substrate 22 is conveyed to the substrate unloading section 10 by the conveying mechanism 8 .

[0035] In step S611, the substrate 22 is transported from the alignment unit 6 to a predetermined target position by the transport mechanism 8. In step S612, the substrate 22 is transported from the predetermined target position to the alignment unit 6. For example, the predetermined target position can be set to a position immediately before the carrier transfer port 7, to which the substrate 22 is to be transported. Then, in step S613, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement.

[0036] Steps S611, S612, and S613 are an example of an evaluation process in which the alignment unit 6 measures the alignment error of the substrate after the substrate 22, aligned by the alignment unit 6, is transported through a predetermined path by the transport system 3. The alignment error detected in the evaluation process represents the positional deviation of the substrate 22 that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 through the predetermined path. In other words, the alignment error obtained in the evaluation process can be considered the amount of positional deviation that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 to the open wafer cassette 71 positioned at the carrier transfer port 7 in the subsequent step S615.

[0037] In step S614, the control unit 11 determines whether the alignment error detected in step S613 (the alignment error detected during the evaluation process) is smaller than the judgment criterion. A finding that the alignment error detected in step S613 is smaller than the judgment criterion indicates that no problems will occur even when the transport mechanism 8 transports the substrate 22 to the open wafer pod 71 positioned at the carrier transfer port 7 in the subsequent step S615. The judgment criterion can be determined based on this purpose. In one example, the judgment criterion can be determined to ensure that the edge of the substrate 22 does not collide with the sidewall 710 when the substrate 22 is accommodated in the slot 710a of the open wafer pod 71.

[0038] If the control unit 11 determines that the alignment error detected in step S613 is less than the judgment reference, the process proceeds to step S615. If the control unit 11 determines that the alignment error detected in step S613 is greater than the judgment reference, the process proceeds to step S616. In step S615, the substrate 22 is transferred from the alignment unit 6 to the open cassette 71 located in the carrier transfer port 7 by the transfer mechanism 8 and stored in the open cassette 71. Executing step S616 means that when the transfer mechanism 8 transfers the substrate 22 from the alignment unit 6 to the open cassette 71, there is a risk of the substrate 22 colliding with the sidewall 710 of the open cassette 71. Therefore, in step S616, an error notification is issued. For example, the error notification can be implemented by prompting the operator to retrieve the substrate 22.

[0039] In the above example, the transfer destination of the substrate 22 in step S615 is the open cassette 71, but the transfer destination can be set arbitrarily. Alternatively, a transfer destination can be selected from a plurality of transfer destination candidates. For example, transfer destinations other than the open cassette 71 include the pattern forming unit 4 (exposure unit 20) and the substrate unloading unit 10.

[0040] According to the first embodiment, even when sufficient holding force cannot be obtained to transport a substrate, it is possible to evaluate the positional deviation of the substrate that may occur during transport, and if the substrate can be safely transported, the substrate can be transported to an alternative transport destination such as an open cassette. This can reduce the frequency of errors that cause the substrate processing apparatus 1 to stop, thereby improving the operating efficiency of the substrate processing apparatus 1.

[0041] In the above-described embodiment, the evaluation process from steps S611 to S613 is executed when it is determined that the holding force on the substrate is less than a predetermined value. However, the evaluation process may be performed constantly. For example, if the alignment error obtained from the evaluation process is less than the first reference for transporting the substrate to the exposure unit, the substrate can be transported to the exposure unit. Alternatively, if the alignment error obtained from the evaluation process is greater than the first reference for transport to the exposure unit but less than the second reference for transport to another destination, the substrate can be transported to another destination.

[0042] Step S615 can be understood as an example of a step in which the control unit 11 determines whether the substrate can be transported to the predetermined destination based on the alignment error obtained through the evaluation process. Alternatively, step S615 can be understood as an example of a step in which the control unit 11 determines whether the substrate can be transported to the predetermined destination based on the magnitude of the alignment error obtained through the evaluation process.

[0043] In step S615, the control unit 11 may determine, based on the alignment error obtained from the evaluation process, which of the multiple transport destinations to transfer the substrate to. Such multiple transport destinations may include an exposure unit, in other words, a pattern forming unit that forms a pattern on the substrate. These multiple transport destinations may also include an open cassette, a substrate loading unit, and a substrate unloading unit. If the control unit 11 determines that the substrate cannot be transferred to any of the multiple transport destinations, it may notify the user that an error has occurred.

[0044] The following describes the operation (control method) of the substrate processing apparatus 1 according to the second embodiment by way of example with reference to FIG7 . Matters not mentioned in the second embodiment can be handled in accordance with the first embodiment. In the second embodiment, the substrate transport speed of the transport system can be lowered below a reference speed if the substrate holding force is determined to be less than a predetermined value. Alternatively, in the second embodiment, the substrate transport speed of the transport system can be lowered below a reference speed if the alignment error obtained from the evaluation process is greater than a threshold value.

[0045] The operation shown in Figure 7 is controlled by the control unit 11. In step S802, the substrate 22 is loaded into the substrate loading unit 9. Then, in step S803, the holding force of the transport system 3 on the substrate 22 is detected. Then, in step S804, the control unit 11 determines whether the holding force on the substrate 22 detected in step S803 is less than a specified value. If the holding force on the substrate 22 is determined to be less than the specified value, the control unit 11 proceeds to step S805. If the holding force on the substrate 22 is determined to be greater than the specified value, the control unit 11 proceeds to step S806. A holding force on the substrate 22 greater than the specified value indicates that the supply mechanism 5 can transport the substrate 22 to the pattern forming unit 4. A holding force on the substrate 22 less than the specified value indicates that a problem may occur when the supply mechanism 5 transports the substrate 22 to the pattern forming unit 4.

[0046] In step S805, the control unit 11 sets the transport speed of the substrate 22 by the transport mechanism 8 to a speed lower than the reference speed. This reduces the possibility of positional deviation of the substrate 22 during transport. In step S806, the substrate 22 is transported by the transport mechanism 8 to the alignment unit 6. Then, in step S807, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement.

[0047] Next, in step S808, the control unit 11 determines whether the transport speed of the substrate 22 by the transport mechanism 8 is set to a speed lower than the reference speed. If the transport speed of the substrate 22 by the transport mechanism 8 is set to a speed lower than the reference speed, the control unit 11 proceeds to step S813; otherwise, the control unit 11 proceeds to step S809. In step S809, the substrate 22 is transported to the pattern forming unit 4 by the supply mechanism 5. In step S810, the substrate 22 is exposed in the pattern forming unit 4. In step S811, the substrate 22 is transported to the substrate unloading unit 10 by the transport mechanism 8.

[0048] In step S813, the substrate 22 is transported from the alignment unit 6 to a predetermined target position by the transport mechanism 8. In step S814, the substrate 22 is transported from the predetermined target position to the alignment unit 6. For example, the predetermined target position can be set to the target position to which the substrate 22 is to be transported, that is, a position immediately before the carrier transfer port 7. Then, in step S815, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement.

[0049] Steps S813, S814, and S815 are examples of evaluation processing in which the alignment unit 6 measures the alignment error of the substrate after the substrate 22, aligned by the alignment unit 6, is transported through a predetermined path by the transport system 3. This evaluation process assesses the positional deviation (alignment error) of the substrate 22 that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 through the predetermined path. In other words, the alignment error obtained in this evaluation process can be considered the amount of positional deviation that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 to the open wafer cassette 71 positioned at the carrier transfer port 7 in the subsequent step S817.

[0050] In step S816, the control unit 11 determines whether the alignment error detected in step S815 (the alignment error detected in the evaluation process) is smaller than the determination reference. A finding that the alignment error detected in step S815 is smaller than the determination reference indicates that no problems will occur even when the substrate 22 is transferred by the transfer mechanism 8 to the open wafer cassette 71 located in the carrier transfer port 7 in the subsequent step S817.

[0051] If the control unit 11 determines in step S816 that the detected alignment error is less than the determination reference, the process proceeds to step S817. If the control unit 11 determines in step S816 that the detected alignment error is greater than the determination reference, the process proceeds to step S818. In step S817, the substrate 22 is transported from the alignment unit 6 to the open wafer cassette 71 located in the carrier transfer port 7 by the transport mechanism 8 and is stored in the open wafer cassette 71.

[0052] In step S818, the control unit 11 determines whether the set substrate conveying speed is the minimum speed. If it is the minimum speed, the process proceeds to step S820; otherwise, the process proceeds to step S819.

[0053] Executing step S820 means that when the transport mechanism 8 transports the substrate 22 from the alignment unit 6 to the open cassette 71, there is a risk of a problem, such as the substrate 22 colliding with the sidewall 710 of the open cassette 71. Therefore, in step S820, an error notification is issued. For example, this error notification can be implemented by prompting the operator to retrieve the substrate 22. In step S819, the control unit 11 further reduces the transport speed set for the transport mechanism 8 to transport the substrate 22, and proceeds to the aforementioned step S813.

[0054] In the second embodiment, the frequency of error occurrence can be reduced compared to the first embodiment.

[0055] The following describes the operation (control method) of the substrate processing apparatus 1 according to the third embodiment by way of example, with reference to FIG8 . Matters not discussed in the third embodiment can be handled in accordance with the first embodiment. In the third embodiment, the control unit 11 compensates for the substrate offset in the alignment unit 6 based on the alignment error obtained through the evaluation process, and then causes the transport system 3 (transport mechanism 8) to transport the substrate.

[0056] In the third embodiment shown in FIG8 , step S616 in the first embodiment shown in FIG6 can be replaced with steps S617 and S618. In step S614, the control unit 11 determines whether the alignment error detected in step S613 (the alignment error detected during the evaluation process) is less than a determination reference. A finding that the alignment error detected in step S613 is less than the determination reference indicates that, in the subsequent step S615, no problems will occur even when the transport mechanism 8 transports the substrate 22 to the open wafer cassette 71 located at the carrier transfer port 7.

[0057] If the control unit 11 determines that the alignment error detected in step S613 is less than the determination reference, the process proceeds to step S615. If the control unit 11 determines that the alignment error detected in step S613 is greater than the determination reference, the process proceeds to step S617. In step S615, the substrate 22 is transferred from the alignment unit 6 to the open wafer cassette 71 located in the carrier transfer port 7 by the transfer mechanism 8 and is stored in the open wafer cassette 71.

[0058] In step S617, the alignment unit 6 aligns the substrate 22 based on the alignment error obtained in step S613. Then, in step S618, the control unit 11 controls the alignment unit 6 based on the alignment error obtained in step S613 to compensate for the misalignment of the substrate 22. For example, it can be assumed that the positional deviation that may occur when the substrate 22 is transported from the alignment unit 6 to the carrier interface 7 by the transport mechanism 8 is equal to the alignment error obtained in step S613. In this case, if the alignment error obtained in step S613 is (ΔX, ΔY, Δθ), the compensation can be set to (-ΔX, -ΔY, -Δθ). Subsequently, in step S615, the substrate 22 is transported from the alignment unit 6 by the transport mechanism 8 to the open wafer cassette 71 located at the carrier interface 7 and is stored in the open wafer cassette 71.

[0059] The following describes, by way of example, the operation (control method) of the substrate processing apparatus 1 according to the fourth embodiment with reference to FIG. Matters not discussed in the fourth embodiment can be handled in accordance with the first embodiment. In the fourth embodiment, if the holding force on the substrate 22 detected in step S603 is determined to be less than a predetermined value, the substrate is transported to a destination selected from a plurality of candidate destinations. The fourth embodiment shown in FIG. 9 adds steps S818 to S621 to the first embodiment shown in FIG. 6 .

[0060] In step S606, the control unit 11 determines whether the holding force for the substrate 22 detected in step S603 is greater than a predetermined value. If the control unit 11 determines that the holding force for the substrate 22 is greater than the predetermined value, the process proceeds to step S607. If the control unit 11 determines that the holding force for the substrate 22 is less than the predetermined value, the process proceeds to step S618.

[0061] In step S618, the substrate 22 is transported from the alignment unit 6 to the first target position by the transport mechanism 8. In step S619, the substrate 22 is transported from the first target position to the alignment unit 6 by the transport mechanism 8. For example, the first target position can be set to a position before the substrate 22 comes into contact with the exposure unit 20. Then, in step S620, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement.

[0062] Steps S618, S619, and S620 are an example of a first evaluation process in which the alignment unit 6 measures the alignment error of the substrate after the substrate 22, aligned by the alignment unit 6, is transported by the transport system 3 through a predetermined path passing through the first target position. The first evaluation process can evaluate the positional deviation (alignment error) of the substrate 22 that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 through the first predetermined path. In other words, the alignment error obtained in the first evaluation process can be considered the amount of positional deviation that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 in the subsequent steps.

[0063] In step S621, the control unit 11 determines whether the alignment error detected in step S620 (the alignment error detected in the evaluation process) is smaller than a first criterion for determination. A finding that the alignment error detected in step S620 is smaller than the first criterion for determination indicates that the image can be transported to the exposure unit 20. From another perspective, the first criterion can be set to ensure safe transport to the exposure unit 20.

[0064] If the control unit 11 determines that the alignment error detected in step S620 is smaller than the first reference for determination, the process proceeds to step S607 . If the control unit 11 determines that the alignment error detected in step S620 is larger than the reference for determination, the process proceeds to step S611 .

[0065] In step S607, the substrate 22 is conveyed by the supply mechanism 5 to the pattern forming unit 4. In step S608, the substrate 22 is exposed in the pattern forming unit 4. In step S609, the substrate 22 is conveyed by the conveying mechanism 8 to the substrate unloading unit 10. Therefore, even if it is determined in step S606 that the holding force of the substrate 22 is less than the specified value, if it is determined that the alignment error detected in the evaluation process is less than the first reference, the substrate 22 is conveyed to the exposure unit 20 and exposed.

[0066] In step S611, the substrate 22 is transported from the alignment unit 6 to the second target position by the transport mechanism 8. In step S612, the substrate 22 is transported from the second target position to the alignment unit 6 by the transport mechanism. For example, the second target position can be set to a position immediately before the carrier interface 7, to which the substrate 22 is to be transported. Then, in step S613, the alignment error of the substrate 22 is measured in the alignment unit 6, and the substrate 22 is aligned based on the measurement.

[0067] Steps S611, S612, and S613 are examples of a second evaluation process in which the alignment unit 6 measures the alignment error of the substrate after the substrate 22, aligned by the alignment unit 6, is transported by the transport system 3 through a second path passing through a second target position. The second evaluation process can evaluate the positional deviation of the substrate 22 that may occur when the transport system 3 (transport mechanism 8) transports the substrate 22 through the second path. In other words, the alignment error obtained in the second evaluation process can be considered as the amount of positional deviation that may occur when the transport system 3 transports the substrate 22 to the open wafer cassette 71 positioned at the carrier transfer port 7 in the subsequent step S615.

[0068] In step S614, the control unit 11 determines whether the alignment error detected in step S613 (the alignment error detected during the evaluation process) is less than the second criterion for determination. A finding that the alignment error detected in step S613 is less than the second criterion for determination means that, in the subsequent step S615, no problem will occur even if the transport mechanism 8 transports the substrate 22 to the open cassette 71 positioned at the carrier transfer port 7. The second criterion for determination can be determined based on this purpose.

[0069] The third embodiment can be understood as an example of transporting a substrate to a destination selected from a plurality of transport destinations. The plurality of transport destinations may have a priority order, and the higher the priority order, the smaller the allowable amount of alignment error (first reference, second reference) obtained by the evaluation process can be set.

[0070] If the output of sensor 89 indicates that the holding force on the substrate is less than a specified value, the control unit 11 can control the evaluation process using the first path as the default path. The first path is assigned to the first transport destination with the highest priority. If the alignment error obtained from the evaluation process using the first path meets the first criterion, the control unit 11 can control the transport system 3 to transport the substrate to the first transport destination. If the alignment error obtained from the evaluation process using the first path does not meet the first criterion, the control unit 11 can control the evaluation process using the second path as the default path. The second path is assigned to the second transport destination with the highest priority. If the alignment error obtained from the evaluation process using the second path meets the second criterion, the control unit 11 can control the transport system 3 to transport the substrate to the second transport destination.

[0071] The following describes an article manufacturing method in which the substrate processing apparatus 1 is configured as a pattern forming apparatus and used to manufacture an article. The article manufacturing method includes: controlling the substrate processing apparatus 1 according to the control method described above to process a substrate, thereby forming a pattern on the substrate; and processing the substrate having the pattern formed thereon, thereby obtaining an article. The pattern can be formed in step S608 or S810. If the substrate processing apparatus 1 is configured as an exposure apparatus, a latent image is formed as a pattern on the photoresist film of the substrate in step S608 or S810, and this latent image can be converted into a physical pattern through a development step. The step of processing the substrate having the pattern formed thereon may include a development step, or may include processing (e.g., etching) the substrate after the development step.

[0072] While preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist of the invention.

[0073] 1: Substrate processing equipment 3: Transport system 4: Pattern forming device 6: Alignment 7: Vehicle interface 8: Transport mechanism 9:Substrate loading department 10:Substrate unloading part 11: Control Department 20: Exposure Department

Claims

1. A substrate processing apparatus, characterized in that it comprises: a processing unit for processing a substrate; a measuring unit for measuring a positional deviation of the substrate; a driving unit for driving the substrate to correct the positional deviation; a transport unit for transporting the substrate; and a control unit for controlling the transport unit, wherein the control unit controls the transport unit to transport the substrate to the processing unit when the holding force of the transport unit on the substrate is greater than a predetermined value, and after correcting the positional deviation when the holding force of the transport unit on the substrate is less than a predetermined value, the control unit transports the substrate from the measuring unit to a wafer cassette containing the substrate, and then transports it to the measuring unit to measure the positional deviation of the substrate, and controls the transport unit based on the positional deviation.

2. The substrate processing apparatus as described in claim 1, wherein, When the holding force is less than the specified value, the control unit moves the substrate to a specified position on the path to the wafer cassette and then moves it to the measurement unit to measure the positional deviation of the substrate.

3. The substrate processing apparatus as described in claim 1, wherein, When the holding force is less than the specified value, the control unit moves the substrate along the path to the wafer cassette and then moves it to the measurement unit to measure the positional deviation of the substrate.

4. The substrate processing apparatus as described in claim 1, wherein, When the holding force is less than the specified value, the aforementioned control unit is driven by the aforementioned drive unit to correct the measured position deviation.

5. The substrate processing apparatus as described in claim 1, wherein, It also includes a sensor to detect the aforementioned holding force, and the aforementioned control unit controls the aforementioned conveying unit based on the measured position deviation when the aforementioned sensor detects that the aforementioned holding force is less than a predetermined value.

6. The substrate processing apparatus as described in claim 1, wherein, The aforementioned control unit determines whether the aforementioned substrate can be transported to the aforementioned wafer cell based on the measured positional deviation when the aforementioned holding force is less than the aforementioned predetermined value.

7. The substrate processing apparatus as described in claim 1, wherein, The aforementioned control unit, when the aforementioned holding force is less than the aforementioned predetermined value, determines whether the aforementioned substrate can be transported to the aforementioned wafer cell based on the magnitude of the aforementioned positional deviation measured.

8. The substrate processing apparatus as described in claim 5, wherein, Based on the measured positional deviation, the aforementioned control unit determines which of the multiple transport destinations to transport the aforementioned substrate to.

9. The substrate processing apparatus as described in claim 8, wherein, The aforementioned multiple transport destinations include the pattern forming section where the aforementioned substrate is patterned.

10. The substrate processing apparatus as described in claim 9, wherein, The aforementioned multiple transport destinations also include the aforementioned wafer cassette; the substrate loading section has a support section to support the aforementioned substrate being loaded. And a substrate removal section, having a support section to support the aforementioned substrate that is being removed.

11. The substrate processing apparatus as described in claim 8, wherein, If the aforementioned control unit determines that it is unable to transport the aforementioned substrate to any of the aforementioned multiple transport destinations, it will notify that an error has occurred.

12. The substrate processing apparatus as described in claim 8, wherein, The aforementioned multiple transport destinations have a priority order; the higher the priority order, the smaller the allowable amount of the aforementioned positional deviation.

13. The substrate processing apparatus as described in claim 12, wherein, If the output of the aforementioned sensor indicates that the holding force on the aforementioned substrate is less than the aforementioned predetermined value, the aforementioned control unit moves the substrate to the first transport destination, which is the first priority, and then measures the first position deviation of the aforementioned substrate. If the aforementioned first position deviation meets the first reference, the aforementioned control unit controls the aforementioned transport unit to move the aforementioned substrate to the aforementioned first transport destination. If the aforementioned first position deviation does not meet the aforementioned first reference, the aforementioned control unit moves the substrate to the second transport destination, which is the second priority, and then measures the second position deviation of the aforementioned substrate. If the aforementioned second position deviation meets the second reference, the aforementioned control unit controls the aforementioned transport unit to move the aforementioned substrate to the aforementioned second transport destination.

14. The substrate processing apparatus as described in claim 1, wherein, If the holding force is less than the specified value and the measured position deviation is greater than the reference, the control unit reduces the transport speed of the transport unit on the substrate.

15. The substrate processing apparatus as described in claim 1, wherein, When the holding force is less than the specified value, the control unit, based on the measured position deviation, causes the transport unit to transport the substrate after the drive unit corrects the deviation of the substrate.

16. A substrate processing apparatus for processing substrates, characterized by comprising: a measuring unit for measuring a positional deviation of the substrate; a driving unit for driving the substrate to correct the positional deviation; a transport unit for transporting the substrate; and a control unit that, after driving the transport unit to transport the substrate, returns to the measuring unit to remeasure the positional deviation of the substrate, and, based on the positional deviation obtained from the remeasurement, determines that the substrate cannot be transported to any of a plurality of transport destinations, and notifies that an error has occurred.

17. The substrate processing apparatus as described in claim 16, wherein, The aforementioned multiple transport destinations include a pattern forming unit that forms a pattern on the aforementioned substrate; a wafer cassette that houses the aforementioned substrate; a substrate loading unit that has a support portion to support the loaded substrate; and a substrate unloading unit that has a support portion to support the unloaded substrate.

18. A substrate processing apparatus for processing substrates, characterized by comprising: a measuring unit for measuring a positional deviation of the substrate; a driving unit for driving the substrate to correct the positional deviation; a transport unit for transporting the substrate; and a control unit that, after driving the transport unit to transport the substrate, returns to the measuring unit to remeasure the positional deviation of the substrate, and determines which of a plurality of transport destinations to transport the substrate to based on the positional deviation obtained from the remeasurement and a tolerance of the positional deviation, wherein the higher the priority of the plurality of transport destinations, the smaller the tolerance.

19. A control method for controlling the handling of a substrate, characterized in that it includes: The first control step involves controlling the transport of the substrate to a processing unit when the holding force of the substrate held by the transport unit is greater than a predetermined value; and the second control step involves controlling the transport of the substrate when the holding force is less than a predetermined value. The second control step includes: a first step of measuring the positional deviation of the substrate with a measuring unit; a second step of driving the substrate to correct the positional deviation; a third step of transporting the substrate from the measuring unit to a wafer cassette containing the substrate after correcting the positional deviation, and then transporting it to the measuring unit to measure the positional deviation of the substrate; and a fourth step of controlling the transport of the substrate based on the positional deviation.

20. The control method as described in claim 19, wherein, It also includes a fifth step, in which, when the aforementioned holding force is greater than a predetermined value, the aforementioned processing unit is controlled to form a pattern on the aforementioned substrate.

21. A control method for controlling the transport of a substrate, characterized in that it includes: a first step of measuring the positional deviation of the substrate; a second step of driving the substrate to correct the positional deviation; a third step of measuring the positional deviation of the substrate again after driving and transporting the substrate; and a fourth step of notifying an error that an error has occurred if, based on the positional deviation obtained from the second measurement, it is determined that the substrate cannot be transported to any of a plurality of transport destinations.

22. A control method for controlling substrate transport, characterized in that it includes: a first step of measuring the positional deviation of the substrate; a second step of driving the substrate to correct the positional deviation; a third step of measuring the positional deviation of the substrate again after driving and transporting the substrate; and a fourth step of determining which of a plurality of transport destinations to transport the substrate to based on the positional deviation obtained from the second measurement and the allowable amount of the positional deviation, wherein the higher the priority of the plurality of transport destinations, the smaller the allowable amount.

23. A method for manufacturing an article, characterized in that it comprises: The step of transporting the substrate by means of the control method described in claim 19; the step of forming a pattern on the substrate transported in the aforementioned steps; The step of processing the aforementioned substrate on which the aforementioned pattern is formed to obtain an article.

24. A substrate processing program that activates the control unit of the aforementioned substrate processing apparatus to execute the control method described in claim 19.

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