TWI882275B - Substrate transport system, lithography device and method for manufacturing article - Google Patents

Abstract

A substrate transport system transports a substrate to a predetermined position, comprising: a hand that holds the substrate by suction; a sensor that measures the pressure between the hand and the substrate; and a control unit that calculates the time taken for suction of the substrate due to the change in the inclination of a driving axis that drives the hand based on the measurement result of the sensor, and determines whether to derive the relative movement amount of the hand and the substrate until the substrate is suctioned to the hand when at least one of the hand and the substrate is moved in a direction toward the hand and the substrate, based on the time taken for suction of the substrate.

Description

Substrate transport system, lithography device and method for manufacturing article

The present invention relates to a substrate transport system, a lithography device and a method for manufacturing an article.

A substrate processing apparatus is used in the substrate processing process included in the manufacturing process of semiconductor devices, liquid crystal display devices, etc. In the substrate processing apparatus, a substrate is transported to each processing unit by a transport unit.

Since the transport unit is driven continuously for a long period of time, the drive part deteriorates due to wear, etc. As a result, the gap between the units changes when the substrate is transferred, causing interference between the substrate and the transport unit.

In order to prevent such interference, there is a substrate transport device (Japanese Patent No. 5689096) that measures a deviation between the timing of the vacuum sensor's response during the adsorption of the substrate and the timing serving as a reference, and determines whether the transport is possible. In addition, there is a known system (Japanese Patent No. 5522596) that measures a time period from when the adsorption pressure when the adsorption pad and the substrate are in contact to when the adsorption pressure when the substrate is adsorbed, and outputs an alarm.

However, in the aforementioned method, it is difficult to grasp the position of the transport unit in the system based on the adsorption state.

The purpose of the present invention is to provide a substrate transport system that derives the distance between the transport unit (hand) and the substrate based on the adsorption state of the substrate, so that the position of the hand can be grasped within the system. In order to achieve the above-mentioned purpose, a substrate transport system as one aspect of the present invention is a substrate transport system that transports the substrate to a predetermined position, and comprises: a hand that holds the substrate by suction; a sensor that measures the pressure between the hand and the substrate; and a control unit that obtains the time taken for the suction of the substrate that changes due to the change in the inclination of the driving axis that drives the hand based on the measurement result of the sensor, and determines whether to derive the relative movement amount of the hand and the substrate until the substrate is sucked by the hand when at least one of the hand and the substrate is moved in a direction in which the hand and the substrate are close to each other, based on the time taken for the suction of the substrate.

Further features of the present invention will become clear from the following embodiments (with reference to the drawings).

The preferred embodiment of the present invention is described below based on the drawings. In addition, the following embodiment does not limit the scope of the patent application of the inventor. In the embodiment, although a plurality of features are recorded, it is not limited to all of these plurality of features being essential to the invention; in addition, a plurality of features can be combined arbitrarily. Furthermore, in the drawings, the same reference symbols are marked for the same or identical structures, and repeated descriptions are omitted. In addition, in this specification and drawings, basically, directions are represented by an XYZ coordinate system. In this XYZ coordinate system, the vertical direction is the Z axis, and the horizontal plane perpendicular to the vertical direction is the XY plane, and the axes are mutually orthogonal. Among them, in the case of an XYZ coordinate system recorded in each drawing, this coordinate system takes precedence. In addition, the pressure values in each embodiment are based on atmospheric pressure.

FIG1 is a schematic diagram illustrating the structure of a substrate processing device 1 as one aspect of the present invention, and is a diagram of the substrate processing device 1 when viewed from the top. The substrate processing device 1, in this embodiment, is specifically implemented as an exposure device that exposes the pattern of the original plate (mask, multiplication mask) to the substrate via a projection optical system. The substrate processing device 1 is not limited to an exposure device. For example, the substrate processing device 1 may be a drawing device that draws on the substrate through an electron beam, an ion beam, etc., and forms a pattern on the substrate. In addition, the substrate processing device 1 may also be other lithography devices; for example, it may also be an imprinting device that forms a pattern on the substrate by molding an imprinting material on the substrate through a mold. Alternatively, the substrate processing device 1 may be other devices for processing substrates such as wafers, glass, etc., such as ion implantation devices, developing devices, etching devices, film forming devices, annealing devices, sputtering devices, and evaporation devices. In addition, the substrate processing device 1 may also be a flattening device for flattening a composition on a substrate using a flat plate.

As shown in FIG. 1 , a substrate processing apparatus 1 has a chamber 2 covering the entire apparatus, and inside the chamber, there are: an exposure processing body 20 for performing exposure processing; an exposure unit 4 for accommodating the exposure processing body 20; and a substrate transport system 3 for transporting a substrate to a predetermined position.

The substrate transport system 3 comprises: a supply mechanism 5 that supplies substrates; a pre-alignment section 6; a carrier port 7 that carries an open box that can accommodate a plurality of substrates; a transport mechanism 8 that transports the substrate to a predetermined position as appropriate; and a stage 9 that temporarily carries the substrate. In the pre-alignment section 6, the substrate is positioned before exposure processing. In addition, the substrate transport system 3 is provided with a control section 10. In addition, the transport mechanism 8 and the supply mechanism 5 have a hand, which is a transport unit for transporting the substrate. In each embodiment, although the control section 10 is assumed to perform the control of the substrate transport system 3 as the main action, it can also perform the overall control of the substrate processing device 1 at the same time, without particular limitation. In addition, the stage 9 has a supporting member 91 for supporting the substrate on the upper surface.

In addition, this carrier port 7 can also be made into a structure for replacing an open box and placing a closed carrier. In addition, the conveying mechanism 8 is, for example, a horizontal multi-joint robot (selective compliance assembly robot).

FIG2 is a schematic diagram showing the structure of the exposure processing main body 20. The exposure processing main body 20 includes: a magnification mask 21; a magnification mask stage (master stage) 24 holding the magnification mask 21; an illumination device 23; a projection optical system 25; and a substrate stage 26 holding a substrate 22. In addition, the exposure processing main body 20 adopts a step-and-repeat method or a step-and-scan method to project the pattern formed on the magnification mask 21 onto the substrate 22.

The lighting device 23 has a light source and a lighting optical system (not shown) to illuminate the zoom mask 21. As for the light source, for example, a pulse light source (laser) is used. The lasers that can be used are ArF excimer lasers with a wavelength of about 193nm, F2 excimer lasers with a wavelength of about 153nm, and the like. In addition, the type of laser is not limited to the excimer laser, and for example, a YAG laser can also be used, and the number of lasers is also not limited. Furthermore, when a laser is used as the light source, it is preferred to use a beam shaping optical system that shapes the parallel light beam from the laser light source into a desired beam shape, and an incoherent optical system that makes the coherent laser incoherent. Furthermore, the light source that can be used is not limited to a pulse light source, and one or more continuous light sources such as mercury lamps and xenon lamps can also be used. Illumination optical system, including lens, reflector, light integrator, aperture, etc.

The magnification mask 21 is, for example, a master plate made of quartz glass, on which a pattern to be transferred (for example, a circuit pattern) is formed. The magnification mask stage 24 can move in the horizontal direction while holding the magnification mask 21.

The projection optical system 25 projects the pattern on the magnification mask 21 illuminated by the exposure light from the illumination device 23 onto the substrate 22 at a predetermined magnification (e.g., 1/4 or 1/5). The projection optical system 25 may be an optical system consisting of only a plurality of refractive lens elements, or an optical system consisting of a plurality of refractive lens elements and at least one concave mirror (reflective refractive optical system). Alternatively, the projection optical system 25 may be an optical system consisting of a plurality of refractive lens elements and at least one diffractive optical element such as a Kinoform, or a total reflection mirror type optical system.

The substrate 22 is a substrate to be processed, for example, a single crystal silicon substrate on which an anti-etching agent is applied. In addition, the substrate stage 26 is configured to be movable in the horizontal direction while holding the substrate 22. For example, when a step-and-scan method is adopted, the magnification mask stage 24 and the substrate stage 26 are moved in the horizontal direction in synchronization with each other.

Next, the process of transporting the substrate is described. First, the substrate 22 coated with the anti-etching agent is transported to the substrate transport system 3. The transported substrate 22 is placed on the support member 91 protruding from the upper surface of the stage 9. The transport mechanism 8 transports the substrate 22 from the stage 9 to the pre-alignment section 6.

The pre-alignment section 6 adjusts the position of the substrate 22 in the horizontal direction and the rotational direction. The supply mechanism 5 transports the substrate 22 whose position has been adjusted by the pre-alignment section 6 to the substrate stage 26. The substrate stage 26 can move in a plane in the horizontal direction to position the transported substrate 22 at a predetermined processing position. The driving mechanism of the substrate stage 26, for example, uses a linear motor, an electromagnetic actuator, a pulse motor, etc., which are not shown in the figure. Although an example of transporting the substrate 22 by the transport mechanism 8 and the supply mechanism 5 is described here, the transport destination of the substrate 22 is not limited to the above example, and the user can freely set the predetermined position of the transported substrate 22.

<First embodiment> The detailed structure of the transport mechanism 8 is shown in FIG3a. The transport mechanism 8 has a hand 85, which holds and transports the substrate 22 with the hand 85. The shape of the hand 85 is not particularly limited as long as it can obtain the shape of the substrate 22, and it does not need to be the shape shown in FIG3a. On the upper surface of the hand 85, there is a suction port 86 for adsorbing and holding the substrate 22, and the suction port 86 is connected to an exhaust part 88 such as a vacuum pump for exhausting the surrounding gas. In addition, the configuration of the suction port 86 is not particularly limited as long as it can adsorb the substrate 22, and it does not need to be the configuration shown in FIG3a. For example, the suction port can be configured on the entire surface of the hand 85, and a plurality of suction ports can also be configured. Furthermore, a sensor 89 for measuring pressure is provided in the exhaust flow path connecting the exhaust section 88 and the suction port 86. Since the exhaust flow path connecting the exhaust section 88 and the suction port 86 is connected to the space between the substrate 22 and the hand 85, measuring the pressure of this exhaust flow path is substantially equivalent to measuring the pressure of the space between the substrate 22 and the hand 85. In addition, the sensor 89 can be placed at a position where the pressure of the space between the substrate 22 and the hand 85 can be directly measured as long as it can measure the pressure of the space between the substrate 22 and the hand 85.

The transport mechanism 8 has a horizontal drive mechanism 81, a vertical drive mechanism 82, and rotational drive mechanisms 83 and 84 to position the hand 85 in four-axis directions (X, Y, Z, θZ). The vertical drive mechanism 82, the rotational drive mechanisms 83 and 84, and the hand 85 are connected via a drive shaft 87. The combination of the drive mechanisms is not limited to the above examples, and the configuration, type, and number are not limited.

FIG. 3b is a diagram of the conveying mechanism 8 for obtaining the substrate 22 placed on the stage 9 when viewed from the α direction shown in FIG. 3a. The substrate 22 is placed on the support member 91 protruding from the upper surface of the stage 9, and the hand 85 is inserted under the substrate 22. The control unit 10 moves the hand 85 in a direction close to the substrate 22. The exhaust unit 88 exhausts air so that the substrate 22 is adsorbed on the hand 85, so that the hand 85 holds the substrate 22 and transfers the substrate 22 from the stage 9 to the conveying mechanism 8. The substrate 22 is adsorbed on the hand 85, so that the substrate 22 can be transported while being prevented from being displaced during transportation. In addition, the substrate 22 is adsorbed on the hand 85, so that the suction port 86 is blocked through the substrate 22, and the pressure in the exhaust flow path changes from atmospheric pressure to the negative pressure side. By detecting the change in pressure in the exhaust flow path through the sensor 89, the control unit 10 detects that the substrate 22 is adsorbed to the hand 85. That is, it can be known from the measurement value of the sensor 89 that the substrate 22 is adsorbed to the hand 85. In addition, in order to adsorb the substrate 22 to the hand 85, the pressure in the space between the substrate 22 and the hand 85 is reduced, and the pressure in the space between the substrate 22 and the hand 85 is measured through the sensor 89. In this embodiment, the pressure measured by the sensor 89 is used as the adsorption pressure.

The transport mechanism 8 is continuously driven during the operation of the substrate processing apparatus 1. As a result, the drive shaft 87, which is a part of the transport mechanism 8, wears as the transport mechanism 8 is used. As a result, the inclination of the drive shaft 87 changes. The wear and inclination of the drive shaft 87 causes the positions of individual components connected by the drive shaft 87 to change, and as a result, the position of the hand 85 in contact with the substrate 22 also changes.

FIG4a shows an example in which the conveying mechanism 8 obtains the substrate 22 from the supporting member 91 when the drive shaft 87 is not worn and tilted. When the drive shaft 87 is not worn and tilted, as shown in FIG4a, the hand 85 can contact the substrate 22 at a position parallel to the horizontal plane. On the other hand, FIG4b shows an example in which the conveying mechanism 8 obtains the substrate 22 from the supporting member 91 when the drive shaft 87 is worn and tilted. When the drive shaft 87 is worn and tilted, as shown in FIG4b, the hand 85 is not parallel to the substrate 22, and the contact is made at an abnormal position, which may cause damage to the hand 85 and the substrate 22.

g shown in FIG. 4a and FIG. 4b indicates a distance between the upper surface of the hand 85 which is a part of the conveying mechanism 8 and the lower surface of the substrate 22 placed on the supporting member 91; hereinafter referred to as a gap. In FIG. 4a and FIG. 4b, due to the tilt of the drive shaft 87, the gap is different even when the conveying mechanism 8 is driven in the same manner. For example, even when the conveying mechanism 8 is driven in the same manner, when comparing the same position, the gap in FIG. 4a where the drive shaft 87 is not tilted is larger than the gap in FIG. 4b where the drive shaft 87 is tilted. That is, by measuring the gap, the change in the position state of the hand 85 can be grasped.

The flow chart of the operation of the substrate transport system 3 in the present embodiment is shown in FIG5 . In the present embodiment, two measurements, namely, the in-transit measurement and the maintenance measurement, are performed. The production operation is started (S10), and then the in-transit measurement is performed during the substrate transport operation in production (S11). Then, when the production operation is completed (S12), it is determined whether the control unit 10 determines that there is a position abnormality (S13). When the control unit 10 determines that there is a position abnormality, the maintenance measurement as an inspection operation is performed (S14) and ends (S15). When the control unit 10 does not determine that there is a position abnormality, the maintenance measurement is not performed and ends (S15). The maintenance measurement is performed, so that the gap between the hand 85 and the substrate 22 can be measured.

The following describes the sequence of measurement during transport. Measurement during transport is performed when the transport mechanism 8 or the supply mechanism 5 having the hand 85 for transporting the substrate 22 obtains the substrate 22 from an arbitrary location. The arbitrary location is not particularly limited, such as the pre-alignment section 6 or the stage 9, as long as the substrate 22 can be obtained by the hand 85. In addition, when the transport mechanism 8 or the supply mechanism 5 places the substrate 22 at an arbitrary location, the position can also be roughly estimated by using the time required for the adsorption pressure to become the same as the atmospheric pressure. As an example of this embodiment, the situation in which the transport mechanism 8 obtains the substrate 22 from the stage 9 is recorded.

FIG6 is a diagram showing an example in which the transport mechanism 8 obtains the substrate 22 from the support member 91 provided on the stage 9 when the transport mechanism 8 is in a normal position. As shown in FIG6a, the transport mechanism 8 is driven to enter the lower side of the substrate 22, and the hand 85 moves in a manner close to the substrate 22. As shown in FIG6b, the hand 85 obtains the substrate 22.

FIG7 is a graph showing the relationship between the suction pressure, the position of the hand 85, and the elapsed time in the example of FIG6. The solid line of the graph of FIG7 represents the change in the pressure value (measured value) detected by the sensor 89 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9. The dotted line of the graph of FIG7 represents the change in the Z position of the hand 85 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9. The Z position of the hand 85 can be known from the number of pulses of the pulse motor driving the conveying mechanism 8, etc.

When the pressure value for judging that the hand 85 normally adsorbs the substrate 22 is p0 (kPa), the time t1 (msec) corresponding to the pressure value according to the sensor 89 becomes p0 (kPa). At t1 (msec), as shown in FIG. 7 , the Z position of the hand 85 is Z1 (mm). That is, it can be calculated that the gap between the hand 85 and the substrate 22 is approximately Z1 (mm).

FIG8 is a diagram showing an example in which the conveying mechanism 8 obtains the substrate 22 from the supporting member 91 provided on the stage 9 when the conveying mechanism 8 is in an abnormal position. As shown in FIG8a or FIG8c, the conveying mechanism 8 is driven to enter the lower side of the substrate 22, and the hand 85 moves in a manner close to the substrate 22, and the substrate 22 is obtained by the hand 85 as shown in FIG8b or FIG8d. FIG8a and FIG8b, and FIG8c and FIG8d, are different in the position of the sensor 89.

FIG9a is a graph showing the relationship between the suction pressure, the position of the hand 85, and the elapsed time in the example of FIG8a and FIG8b. The solid line of the graph of FIG9a is the change in the pressure value of the sensor 89 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9. The dotted line of the graph of FIG9a is the change in the Z position of the hand 85 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9.

When the pressure value that determines that the hand 85 normally adsorbs the substrate 22 is p0 (kPa), the time t2 (msec) corresponding to the pressure value according to the sensor 89 becomes p0 (kPa). At t2 (msec), as shown in FIG9a, the Z position of the hand 85 is Z2 (mm). That is, it can be calculated that the gap between the hand 85 and the substrate 22 is approximately Z2 (mm). In FIG8a and FIG8b, the sensor 89 is installed on the side of the tilted hand 85 close to the substrate 22. Accordingly, as shown in FIG9a, the time t2 (msec) when the pressure value becomes p0 (kPa) becomes shorter than t1 (msec). In addition, Z2 (mm) becomes smaller than Z1 (mm).

FIG9b is a graph showing the relationship between the suction pressure, the position of the hand 85, and the elapsed time in the example of FIG8c and FIG8d. The solid line of the graph of FIG9b is the change in the pressure value of the sensor 89 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9. The dotted line of the graph of FIG9b is the change in the Z position of the hand 85 relative to the elapsed time when the conveying mechanism 8 obtains the substrate 22 from the stage 9.

When the pressure value that determines that the hand 85 normally adsorbs the substrate 22 is p0 (kPa), the time t3 (msec) corresponding to the pressure value according to the sensor 89 becomes p0 (kPa). At t3 (msec), as shown in FIG9b, the Z position of the hand 85 is Z3 (mm). That is, it can be calculated that the gap between the hand 85 and the substrate 22 is approximately Z3 (mm). In FIG8c and FIG8d, the sensor 89 is installed on the side of the tilted hand 85 away from the substrate 22. Accordingly, as shown in FIG9b, the time t3 (msec) when the pressure value becomes p0 (kPa) becomes longer than t1 (msec). In addition, Z3 (mm) becomes larger than Z1 (mm).

In the above method, the approximate position state of the hand 85 and the substrate 22 can be estimated by the in-transit measurement. Since the in-transit measurement is performed during the substrate transport operation of simply bringing the hand 85 close to the substrate 22 and adsorbing the substrate 22, position abnormalities can be detected without reducing productivity. In addition, in the case of a position abnormality, maintenance measurement is performed to grasp the precise relative position. In addition, although the gaps Z1 (mm), Z2 (mm), and Z3 (mm) between the hand 85 and the substrate 22 are obtained here, as shown by the dotted lines in Figures 7 and 9, the Z position of the hand 85 increases monotonically with respect to the elapsed time. Therefore, knowing the values of the times t1 (msec), t2 (msec), and t3 (msec) is sufficient to estimate the position state, and thus the position of the hand 85 can be estimated by measuring the time required for adsorption of the substrate 22 .

FIG10 shows a flow chart of measurement during transport when the transport mechanism 8 obtains the substrate 22 from the carrier 9. First, the transport mechanism 8 starts to transport the substrate 22 to a predetermined position as a substrate transport action (S20). The transport mechanism 8 is driven to the lower side of the substrate 22 placed on the carrier 9 (S21), and the transport mechanism 8 moves in a manner close to the substrate 22 (S22). Then, suction is started from the suction port 86 (S23), and the sensor 89 starts to measure the adsorption pressure p (kPa), and the measurement is continued (S24). Then, the control unit 10 determines whether the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22 (S25). Here, the pressure value in this embodiment is based on atmospheric pressure as mentioned above.

In step S25, the control unit 10 derives the adsorption state of the hand 85 and the substrate 22 from the measured value of the sensor 89. Here, the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, indicating that the substrate 22 is adsorbed to the hand 85. In addition, when the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is not adsorbed to the hand 85.

When the pressure is less than the reference value p0 (kPa), the control unit 10 measures the time taken for adsorption of the substrate 22, and determines whether the elapsed time t is greater than the user-specified time tu (msec) (S26). Here, the user-specified time tu (msec) is the upper limit of the time required for adsorption that is predetermined by the user based on a design value or an experimental value. When the elapsed time t is greater than the user-specified time tu (msec), the control unit 10 stores it as adsorption not possible (S27), and ends (S31). When it is stored as adsorption not possible in step S27, it is assumed that an abnormality has occurred in the substrate transport system 3, and therefore maintenance authorized by the user is required immediately. If the time tu (msec) specified by the user is less than the time tu (msec), the process returns to step S24, and the sensor 89 continues to measure the adsorption pressure p (kPa). If the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, the control unit 10 measures the time taken to adsorb the substrate 22 and stores it as the elapsed time t (S28).

In this embodiment, the sensor 89 measures the pressure of the exhaust flow path connecting the exhaust part 88 and the suction port 86. When the sensor 89 measures the adsorption pressure p (kPa), it is in the state of sucking air from the suction port 86. That is, the sensor 89 measures the pressure of the space between the hand 85 and the substrate 22 that is depressurized; the pressure changes to a negative pressure compared with the atmospheric pressure. Accordingly, the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa), which is equivalent to the adsorption pressure p (kPa) becoming less than the pressure reference value p0 (kPa).

Here, the time from when the adsorption pressure p (kPa) reaches the pressure reference value p0 (kPa) when the conveying mechanism 8 is in a normal position is defined as the reference adsorption time ta (msec). On the other hand, the time from when the adsorption pressure p (kPa) reaches the pressure reference value p0 (kPa) when the conveying mechanism 8 is in an abnormal position is defined as the abnormal adsorption time. The abnormal position is a situation where the suction port 86 of the hand 85 is closest to and farthest from the substrate 22 in the vertical direction within a range where the conveying mechanism 8 is driven in the horizontal direction without contacting other components. The abnormal adsorption time when the suction port 86 of the hand 85 is closest to the substrate 22 in the vertical direction is tb1 (msec), and the abnormal adsorption time when the suction port 86 is farthest away is tb2 (msec). ta (msec), tb1 (msec) and tb2 (msec) can also be determined by experimentally performing the transport operation, or can be calculated based on physically determined constants. The difference between ta (msec) and tb1 (msec) or tb2 (msec) is defined as the adsorption change threshold t0 (msec) (predetermined value). When calculating the adsorption change threshold t0 (msec), the smaller absolute value of the difference between tb1 (msec) and tb2 (msec) and the reference adsorption time ta (msec) is used.

The adsorption change threshold t0 (msec), for example, when tb1 (msec) is adopted, is defined as in formula (1).

Furthermore, the control unit 10 determines whether the difference between the elapsed time t (msec) and the reference adsorption time ta (msec), that is, whether |ta-t| is greater than the adsorption variation threshold t0 (msec) (S29). If the difference between the elapsed time t (msec) and the reference adsorption time ta (msec) is greater than the adsorption variation threshold t0 (msec) (greater than a predetermined value), the control unit 10 stores it as a position abnormality (S30) and ends (S31). If the difference between the elapsed time t (msec) and the reference adsorption time ta (msec) is less than the adsorption variation threshold t0 (msec) (less than a predetermined value), the control unit 10 directly ends (S31).

Next, the maintenance measurement for the inspection action is explained. As shown in FIG. 5 , after the production operation is completed (S12), it is determined whether the control unit 10 determines that the position is abnormal (S13). If it is determined that the position is abnormal, the maintenance measurement is performed (S14). The maintenance measurement is performed when the conveying mechanism 8 or the supply mechanism 5 having the hand 85 for conveying the substrate 22 obtains the substrate 22 from any place, and the relative position of the conveying mechanism 8 or the supply mechanism 5 and the substrate 22 is measured. Through the maintenance measurement, the position status of the substrate 22 and the conveying mechanism 8 or the supply mechanism 5 can be accurately derived.

FIG11 is a schematic diagram of maintenance measurement when the transport mechanism 8 obtains the substrate 22 from the pre-alignment section 6. As shown in FIG11a, the transport mechanism 8 is driven to the lower side of the substrate 22 and to the lower step position of the pre-alignment section 6. Then, suction is performed from the suction port 86 to adsorb the substrate 22, and the measurement of the adsorption pressure p (kPa) is started through the sensor 89 and the measurement is continued. Then, the control unit 10 confirms whether the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22. Here, the pressure value in the present embodiment is based on the atmospheric pressure as mentioned above. In FIG11a, the hand 85 has not completed the adsorption of the substrate 22, and the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa). Therefore, as shown in FIG11b, the hand 85 is moved a predetermined distance d. In FIG11b, when the adsorption state of the substrate 22 is extracted, the hand 85 has not completed the adsorption of the substrate 22, and the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa). Therefore, as shown in FIG11c, the hand 85 is moved again by a distance d. In FIG11c, the hand 85 has completed the adsorption of the substrate 22, and the absolute value of the adsorption pressure p (kPa) in this case becomes greater than the pressure reference value p0 (kPa). Therefore, as a result of the gap measurement obtained by the maintenance measurement according to the example of FIG. 11, the difference between the height at the time when the hand 85 starts to move close to the substrate 22 for maintenance measurement and the height after the movement can be calculated, that is, 2d can be calculated as the gap. In addition, in the present embodiment, although the method of calculating the movement amount (gap) when the hand 85 is moved a predetermined distance (distance d) toward the substrate 22 is described as above, as long as the movement amount can be derived, there is no particular limitation on the calculation method.

In addition, in the present embodiment, although the gap is obtained by moving the hand 85 in a predetermined distance (distance d) in a direction close to the substrate 22, the substrate 22 may be moved in a direction close to the hand 85. Furthermore, both the substrate 22 and the hand 85 may be moved in a direction close to the substrate 22 and the hand 85. That is, to measure the gap, at least one of the substrate 22 and the hand 85 may be moved in a direction close to the substrate 22 and the hand 85. In this case, the relative movement amount of the hand 85 and the substrate 22 is derived. The movement amount when the hand 85 is moved in a direction close to the substrate 22 and the movement amount when the substrate 22 is moved in a direction close to the hand 85 are the same. Furthermore, the amount of movement when the hand 85 is moved in a direction close to the substrate 22 is the same as the total amount of movement of the substrate 22 and the hand 85 when both the substrate 22 and the hand 85 are moved in a direction close to the substrate 22 and the hand 85. That is, the derivation of the amount of movement in this embodiment is equivalent to the derivation of the relative amount of movement of the hand 85 and the substrate 22.

FIG12 shows a flow chart of the maintenance measurement for the inspection action when the conveying mechanism 8 obtains the substrate 22 from the pre-alignment section 6. First, the conveying mechanism 8 starts the maintenance measurement for the inspection action (S32) and is driven to the lower side of the substrate 22 and the lower step position of the pre-alignment section (S33). Then, suction is started from the suction port 86 (S34). The measurement of the adsorption pressure p (kPa) is started through the sensor 89 and the measurement is continued (S35). After that, in order to stabilize the adsorption pressure, wait for a certain time (S36). This waiting time is sufficient to be about the time required for normal adsorption of the substrate 22 by the hand 85 in advance. After the waiting time has passed, the control unit 10 determines whether the absolute value of the adsorption pressure p (kPa) measured by the sensor 89 is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22 (S37).

In step S37, the control unit 10 derives the adsorption state of the hand 85 and the substrate 22 from the measured value of the sensor 89. When the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is adsorbed to the hand 85. When the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is not adsorbed to the hand 85.

For example, when the pressure reference value is p0 (kPa) or more without moving the hand 85 by the distance d for maintenance measurement, the substrate 22 is adsorbed in the state when the hand 85 is driven to the lower position of the pre-alignment section 6 in step S33. Therefore, this situation becomes a measurement result such as no gap (S42). In the state of no gap, there is a risk that the hand 85 and the substrate 22 will interfere with each other immediately.

In step S37, when the pressure is less than the reference value p0 (kPa), the control unit 10 determines whether the conveying mechanism 8 has reached the driving limit (S38). When the conveying mechanism 8 has reached the driving limit, the gap measurement is deemed impossible (S41), and the process ends (S43). When the conveying mechanism 8 has not reached the driving limit, the conveying mechanism 8 is moved a predetermined distance d in a manner close to the substrate 22 (S39). Furthermore, the control unit 10 determines whether the conveying mechanism 8 has reached the driving limit by moving the conveying mechanism 8 by the distance d (S40). When it is determined that the conveying mechanism 8 has reached the driving limit, the gap measurement is deemed impossible (S41), and the process ends (S43). In step S40, when the transport mechanism 8 has not reached the driving limit, the process returns to step S35.

In step S42, the gap measurement is performed by taking the difference between the height at the time when the hand 85 starts to move close to the substrate 22 for maintenance measurement and the height after the movement, that is, the movement amount of the hand 85 as the gap measurement result (S42), and then ending (S43). Here, the movement amount is generally the product of the spacing d and the number of movements. And, as mentioned above, the movement amount is equivalent to the relative movement amount, so the gap measurement result can also be derived from the relative movement amount.

In addition, the gap measurement result is the gap between the hand 85 and the substrate 22 when the hand 85 moves under the substrate 22 to adsorb the substrate 22. Based on this, the derived gap measurement result (relative movement amount) can be used to calculate the relative position of the substrate 22 and the hand 85 when the hand 85 starts the adsorption operation of adsorbing the substrate 22.

In addition, the gap can be accurately measured by following the maintenance measurement sequence to make the gap d about 50 to 200 μm. If the gap measurement result is outside the range predefined by the user, the conveyance is stopped until it is confirmed that the substrate conveyance system 3 can operate safely. In addition, if the gap measurement becomes impossible, it may be because some abnormality has occurred, so the conveyance is stopped until it is confirmed that the substrate conveyance system 3 can operate safely.

In the above-mentioned measurement during transport, the control unit 10 measures the time taken for the substrate 22 to be adsorbed simultaneously with the action of the hand 85 adsorbing the substrate 22 during the substrate transport action which is a general production action. That is, the position of the transport mechanism 8 or the supply mechanism 5 having the hand 85 for transporting the substrate 22 can be measured during the substrate transport action, without stopping the device one by one to confirm whether the position is abnormal. According to this, the state of the transport unit can be confirmed without reducing the productivity. In addition, when the position of the hand 85 is detected to be abnormal by the measurement during transport, the gap measurement (relative position measurement) according to the maintenance measurement can be automatically performed to measure the precise gap. That is, the precise position state of the substrate 22 and the transport mechanism 8 or the supply mechanism 5 can be estimated. Thus, the user can perform maintenance based on the accurate measurement results measured during maintenance measurement, which can shorten the time spent on maintenance. Furthermore, the substrate transport system 3 is stopped based on the results of relative position measurement, so the risk of damage to the machine can be reduced.

<Second embodiment> Next, the substrate transport system 3 in the second embodiment is described. FIG. 13 shows the structure of the carrier 9 and the transport mechanism 8 in this embodiment. FIG. 13 is a diagram of the carrier 9 and the transport mechanism 8 when viewed from the α direction shown in FIG. 3a, as FIG. 3b in the first embodiment.

As shown in Fig. 13, the hand 85 has a suction port 861 and a suction port 862 at positions symmetrical to the support member 91. In addition, a sensor 891 and an exhaust portion 881 connected to the suction port 861, and a sensor 892 and an exhaust portion 882 connected to the suction port 862 are provided.

The sensor 891 measures the pressure in the exhaust flow path connecting the exhaust section 881 and the suction port 861. The sensor 892 measures the pressure in the exhaust flow path connecting the exhaust section 882 and the suction port 862. In addition, the exhaust section 881 and the exhaust section 882 are independent and different systems. When the substrate 22 is adsorbed on the hand 85 so that the suction port 861 and the suction port 862 are closed, a time difference is generated in the pressure change of the sensor 891 and the sensor 892 according to the relative inclination of the substrate 22 and the hand 85.

FIG. 14 shows a flow chart of measurement during transport when the transport mechanism 8 obtains the substrate 22 from the stage 9 in the present embodiment. First, the transport mechanism 8 starts to transport the substrate 22 to a predetermined position as a substrate transport operation (S50), and the transport mechanism 8 drives to the lower side of the substrate 22 placed on the stage 9 (S51). Furthermore, the transport mechanism 8 moves in a manner close to the substrate 22 (S52), and starts suction from the suction ports 861 and 862 (S53). The sensors 891 and 892 start to measure the adsorption pressure p (kPa), and continue the measurement (S54). Then, the control unit 10 determines whether the absolute value of the adsorption pressure p (kPa) measured by the sensor 891 or the sensor 892 is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22 (S55). Here, the pressure value in this embodiment is based on the atmospheric pressure as described above.

In step S55, the control unit 10 derives the adsorption state of the hand 85 and the substrate 22 from the measured value of the sensor 891 or the sensor 892. When the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is adsorbed to the hand 85. When the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is not adsorbed to the hand 85.

When the pressure is less than the reference value p0 (kPa), the control unit 10 measures the time taken for adsorption of the substrate 22 and determines whether the elapsed time t is greater than the user-specified time tu (msec) (S56). Here, the user-specified time tu (msec) is the upper limit of the time required for adsorption that is predetermined by the user based on the design value or experimental value. When the elapsed time t is greater than the user-specified time tu (msec), the control unit 10 stores it as adsorption not possible (S61) and ends (S66). When it is stored as adsorption not possible in step S61, it is assumed that an abnormality has occurred in the substrate transport system 3, so maintenance by the user is required immediately. When it is less than the user-specified time tu (msec), return to step S54. When the pressure is above the pressure reference value p0 (kPa), the control unit 10 measures the time taken for adsorption and stores it as the first elapsed time t01 (msec) (S57). In addition, another sensor continues to measure the adsorption pressure p (kPa) (S58), and the control unit 10 determines whether the absolute value of the adsorption pressure p (kPa) of the other sensor is above the pressure reference value p0 (kPa) (S59).

In step S59, the control unit 10 derives the adsorption state of the hand 85 and the substrate 22 from the measured value of the sensor 891 or the sensor 892. When the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is adsorbed to the hand 85. When the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is not adsorbed to the hand 85.

If the absolute value of the adsorption pressure p (kPa) of the other sensor is less than the pressure reference value p0 (kPa), the control unit 10 measures the time taken to adsorb the substrate 22 and determines whether the elapsed time t is greater than the user-specified time tu (msec) (S60). If the elapsed time t is greater than the user-specified time tu (msec), the control unit 10 stores it as adsorption not possible (S61) and ends (S66). If it is stored as adsorption not possible in step S61, it is assumed that an abnormality has occurred in the substrate transport system 3, so maintenance by the user is required immediately. If it is less than the user-specified time tu (msec), return to step S58. When the absolute value of the adsorption pressure p (kPa) of the other sensor is greater than the pressure reference value p0 (kPa), the control unit 10 measures the time taken for adsorption and stores it as the second elapsed time t02 (msec) (S62). In addition, the relative inclination Ti of the hand 85 and the substrate 22 is calculated from the first elapsed time t01 (msec) and the second elapsed time t02 (msec) (S63). This relative inclination Ti does not necessarily need to be displayed as an accurate numerical value to show the degree of inclination of the hand 85 relative to the horizontal reference. In the simplest case, the difference between t01 (msec) and t02 (msec) can be used.

Here, the reference relative tilt amount Tia when the conveying mechanism 8 is in a normal position and the relative tilt amount Tib when the conveying mechanism 8 is in an abnormal position are measured in advance, and the relative tilt change threshold Ti0 is calculated in advance. Ti0 is regarded as the difference between Tia and Tib. In the abnormal position, it is expected that the hand 85 is closest to the substrate 22 in the vertical direction within the range where the conveying mechanism 8 does not contact the substrate 22 when it is driven in the horizontal direction.

The control unit 10 determines whether the difference between the relative tilt amount Ti and the reference relative tilt amount Tia is greater than the relative tilt change threshold value Ti0 (S64). When the difference between the relative tilt amount Ti and the reference relative tilt amount Tia is greater than the relative tilt change threshold value Ti0 (greater than the predetermined tilt amount), the control unit 10 determines that it is a position abnormality, stores it (S65), and ends (S66). When the difference between the relative tilt amount Ti and the reference relative tilt amount Tia is less than the relative tilt change threshold value Ti0 (less than the predetermined tilt amount), it ends directly (S66).

This embodiment makes it possible to determine the positional relationship between the hand 85 and the substrate 22, including the element of tilt, and detect positional abnormality of the conveying mechanism 8 with higher accuracy than the first embodiment. In addition, in this embodiment, as in the first embodiment, when a positional abnormality is detected, gap measurement (relative position measurement) is performed as a maintenance measurement for inspection operations.

In addition, in this embodiment, although two adsorption systems are shown as an example, three or more adsorption systems can also be used. The more adsorption systems there are, the more accurately the position of the conveying mechanism 8 can be expected to be known.

<Third embodiment> Next, the substrate transport system 3 in the third embodiment is described. FIG. 15 shows a flow chart of the measurement during transport when the transport mechanism 8 obtains the substrate 22 from the stage 9 in this embodiment. First, the transport mechanism 8 starts to transport the substrate 22 to a predetermined position as a substrate transport action (S70), and the transport mechanism 8 drives to the lower side of the substrate 22 placed on the stage 9 (S71). In addition, the transport mechanism 8 moves in a manner close to the substrate 22 (S72), and starts suction from the suction port 86 (S73). The sensor 89 starts to measure the adsorption pressure p (kPa) and continues the measurement (S74).

As in the first embodiment, when the suction pressure at which the hand 85 is judged to be normally sucking the substrate 22 is p0 (kPa) and the transport mechanism 8 is in a normal position, the time until the suction pressure p (kPa) reaches the pressure reference value p0 (kPa) is defined as the reference suction time ta (msec). Furthermore, when the transport mechanism 8 is in an abnormal position, the time until the suction pressure p (kPa) reaches the pressure reference value p0 (kPa) is defined as the abnormal suction time. The abnormal position is within the range that the conveying mechanism 8 is driven in the horizontal direction and does not contact other structures. It is assumed that the suction port 86 of the hand 85 is closest to the substrate 22 in the vertical direction and the farthest away from it. The abnormal adsorption time when the suction port 86 of the hand 85 is closest to the substrate 22 in the vertical direction is tb1 (msec), and the abnormal adsorption time when the suction port 86 is farthest away from it is tb2 (msec). The difference between ta (msec) and tb1 (msec) or tb2 (msec) is defined as the adsorption change threshold t0 (msec). When calculating the adsorption fluctuation threshold t0 (msec), the smaller absolute value of the difference between tb1 (msec) and tb2 (msec) and the reference adsorption time ta (msec) is used.

The adsorption change threshold t0 (msec), for example, when tb1 (msec) is adopted, is defined as in formula (1).

The control unit 10 determines whether the absolute value of the adsorption pressure p (kPa) of the sensor 89 is greater than the pressure reference value p0 (kPa) (S75). Here, the pressure value in the present embodiment is based on the atmospheric pressure as described above. In step S75, the control unit 10 derives the adsorption state of the hand 85 and the substrate 22 from the measured value of the sensor 89. When the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is adsorbed to the hand 85. In addition, when the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa) at which the hand 85 can normally adsorb the substrate 22, it indicates that the substrate 22 is not adsorbed to the hand 85.

When the absolute value of the adsorption pressure p (kPa) is less than the pressure reference value p0 (kPa), the control unit 10 measures the time taken for adsorption of the substrate 22 and determines whether the elapsed time t is greater than the user-specified time tu (msec) (S76). Here, the user-specified time tu (msec) is the upper limit of the time required for adsorption that is predetermined by the user based on a design value or an experimental value. When the elapsed time t is greater than the user-specified time tu (msec), the control unit 10 stores it as adsorption not possible (S77) and ends (S84). When it is stored as adsorption not possible in step S77, it is assumed that an abnormality has occurred in the substrate transport system 3, and therefore maintenance authorized by the user is required immediately. If it is less than the user-specified time tu (msec), the process returns to step S74. When the absolute value of the adsorption pressure p (kPa) is greater than the pressure reference value p0 (kPa), the control unit 10 measures the time taken for adsorption and stores it as the elapsed time t (msec) (S78).

The control unit 10 determines whether the difference |ta-t| between the elapsed time t (msec) and the reference adsorption time ta (msec) is greater than the adsorption variation threshold t0 (msec) (S79). When |ta-t| is less than the adsorption variation threshold t0 (msec) (less than a predetermined value), the control unit 10 calculates an average value of the t (msec) memorized during the transport of the last five pieces. And, the value of the average elapsed time te (msec) is updated to the calculated average value (S80), and the process ends (S84). In addition, when setting the initial value of the average elapsed time te (msec), it can be determined by performing a transport operation experimentally in advance, and the value can also be used when it can be estimated in advance from the design value.

When the difference |ta-t| between the elapsed time t (msec) and the reference adsorption time ta (msec) is greater than the adsorption change threshold t0 (msec) (greater than a predetermined value), the control unit 10 determines whether the elapsed time t is within the range of ±10% of the elapsed average time te (S81). When the elapsed time t is within the range of ±10% of the elapsed average time te, the control unit 10 determines that the position of the hand 85 is abnormal, stores it (S82), and ends (S84). When the elapsed time t is not within the range of ±10% of the elapsed average time te, the control unit 10 determines that the substrate is abnormal, stores it (S83), and ends (S84). Here, in this embodiment, although the range of the average elapsed time te compared with the elapsed time t is set to ±10% in order to determine the existence of an abnormality, this range can be freely set by the user in conjunction with the substrate transport system 3 and is not particularly limited.

By following the above sequence, when the adsorption time of the substrate 22 changes rapidly relative to the most recent average, it can be determined that the substrate is abnormal, and when it changes slowly, it can be determined that the position of the hand 85 is abnormal. It can be seen that in the case of a substrate abnormality, by taking measures such as removing the substrate, maintenance measurement is not required. Since unnecessary maintenance measurement is not performed, the productivity of the substrate transport system 3 can be prevented from being reduced.

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

<Fourth Implementation Method> Next, a method for manufacturing an article (semiconductor IC element, liquid crystal display element, color filter, MEMS, etc.) using the aforementioned exposure device is described. The article is manufactured by using the aforementioned exposure device to expose a substrate (wafer, glass substrate, etc.) coated with a photosensitive agent, developing the substrate (photosensitive agent), and processing the developed substrate with other well-known processing procedures. Other well-known procedures include etching, anti-etching layer peeling, cutting, bonding, packaging, etc. When using this manufacturing method, articles of higher quality than ever before can be manufactured.

According to the present invention, a substrate transport system can be provided, which can derive the distance between the transport unit (hand) and the substrate based on the adsorption state of the substrate, so that the position of the hand can be grasped in the system. Although the present invention is described with reference to the embodiment, it should be understood that the present invention is not limited to the disclosed embodiment. The scope of the patent application should be interpreted in the broadest way to include various changes, equivalent structures and functions. In this case, priority is claimed to Japanese Patent Application No. 2022-042498 filed on March 17, 2022, and its entire contents are hereby cited.

1: Substrate processing device 2: Chamber 2d: Gap 3: Substrate transport system 4: Exposure section 5: Supply mechanism 6: Pre-alignment section 7: Carrier port 8: Transport mechanism 9: Carrier stage 10: Control section 20: Exposure processing body 21: Reduction mask 22: Substrate 23: Illumination device 24: Reduction mask stage 25: Projection optical system 26: Substrate stage 81: Driving mechanism 82: Driving mechanism 83: Driving mechanism 84: Driving mechanism 85: Hand 86: Suction port 861: Suction port 862: Suction port 87: Driving shaft 88: Exhaust section 881: Exhaust section 882: Exhaust section 89: Sensor 891: Sensor 892: Sensor 91: Support member g: Distance

[FIG. 1] is a schematic diagram showing the structure of a substrate processing device as one embodiment of the present invention. [FIG. 2] is a schematic diagram showing the structure of an exposure processing main body. [FIG. 3] is an example of the structure of a substrate transport system in the first embodiment. [FIG. 4] is an example of a transport mechanism obtaining a substrate from a support member. [FIG. 5] is a flow chart of the operation of the substrate transport system in the first embodiment. [FIG. 6] is an example of a transport mechanism obtaining a substrate when the transport mechanism is in a normal position. [FIG. 7] is a diagram showing the relationship between the suction pressure, the position of the hand, and the elapsed time when the transport mechanism is in a normal position. [FIG. 8] is an example of a transport mechanism obtaining a substrate when the transport mechanism is in an abnormal position. [Figure 9] is a graph showing the relationship between the suction pressure, the position of the hand, and the elapsed time when the transport mechanism is in an abnormal position. [Figure 10] is a flow chart of measurement during transport when the transport mechanism obtains a substrate from a stage. [Figure 11] is a schematic diagram of maintenance measurement when the transport mechanism obtains a substrate from a pre-alignment section. [Figure 12] is a flow chart of maintenance measurement when the transport mechanism obtains a substrate from a pre-alignment section. [Figure 13] is an example of the configuration of a substrate transport system in the second embodiment. [Figure 14] is a flow chart of measurement during transport when the transport mechanism obtains a substrate from a stage in the second embodiment. [Figure 15] is a flow chart of measurement during transport when the transport mechanism in the third embodiment obtains the substrate from the stage.

Claims (14)

A substrate transport system transports a substrate to a predetermined position, comprising: a hand that holds the substrate by suction; a sensor that measures the pressure between the hand and the substrate; and a control unit that obtains the time taken for the suction of the substrate due to the change in the inclination of the drive shaft that drives the hand based on the measurement result of the sensor, and determines whether to derive the relative movement amount of the hand and the substrate until the substrate is sucked by the hand when at least one of the hand and the substrate is moved in a direction in which the hand and the substrate are close to each other, based on the time taken for the suction of the substrate. The substrate transport system of claim 1, wherein the control unit does not derive the relative movement amount when the difference between the reference time and the time spent on the adsorption of the substrate is less than a predetermined value, and derives the relative movement amount when the difference between the reference time and the time spent on the adsorption of the substrate is greater than a predetermined value. As in claim 2, in the substrate transport system, during the action of transporting the substrate to the predetermined position, the control unit simultaneously calculates the time taken for the substrate to be adsorbed while the hand adsorbs the substrate. As in claim 3, the substrate transport system, wherein the control unit controls the hand and at least one of the substrate to approach each other at a predetermined distance and a predetermined number of times until the substrate is adsorbed on the hand, and the control unit derives the relative movement amount based on the predetermined distance and the predetermined number of times. A substrate transport system as claimed in claim 2, wherein, in the process of transporting the substrate to the predetermined position, the control unit detects an abnormality in the position of the hand or the substrate based on the time taken to adsorb the substrate. A substrate transport system as claimed in claim 3, wherein the control unit derives the relative position of the substrate and the hand from the relative movement amount at the time when the hand starts the adsorption action of the substrate. The substrate transport system of claim 3, wherein the hand has: suction ports for adsorbing two or more substrates; and two or more sensors corresponding to the individual suction ports for measuring the pressure between the hand and the substrates; the control unit calculates the time taken by the individual suction ports to adsorb the substrates when transporting the substrates to the predetermined position based on the measured values of the sensors, and derives the tilt of the hand from the calculated time required for adsorbing the substrates. The substrate transport system of claim 7, wherein the control unit does not derive the relative movement amount when the difference between the derived tilt amount of the hand and the tilt amount used as a reference is less than a predetermined tilt amount, and moves at least one of the hand and the substrate in a direction in which the hand and the substrate are close to each other to derive the relative movement amount when the difference between the derived tilt amount of the hand and the tilt amount used as a reference is greater than the predetermined tilt amount. As in claim 3, in the substrate transport system, in the action of transporting the substrate to the predetermined position, the control unit averages the time taken for adsorption of the substrate that has been processed most recently, and makes the calculated average value the average time. When the difference between the time taken as the reference and the time taken for adsorption of the substrate is greater than a predetermined value, the time taken for adsorption of the substrate is compared with the average time, and it is determined that the abnormality is in the substrate or the hand. A substrate transport system transports a substrate to a predetermined position, comprising: a hand that holds the substrate by suction; a sensor that measures the pressure between the hand and the substrate; and a control unit that determines whether to derive the relative movement amount of the hand and the substrate until the substrate is adsorbed on the hand when at least one of the hand and the substrate moves in a direction in which the hand and the substrate approach each other, based on the measurement result of the sensor, and when deriving the relative movement amount, the relative position of the substrate and the hand before the adsorption action of the hand adsorbing the substrate is started is derived based on the relative movement amount. A substrate transport system transports a substrate to a predetermined position, comprising: a hand having two or more suction ports for adsorbing the substrate, and adsorbing and holding the substrate; two or more sensors for measuring the pressure between the hand and the substrate respectively corresponding to the suction ports; and a control unit, which, when transporting the substrate to the predetermined position, obtains the time taken by each of the suction ports to adsorb the substrate based on the measurement result of the sensor, derives the tilt of the hand based on the obtained time taken to adsorb the substrate, and determines whether to derive the relative movement of the hand and the substrate until the substrate is adsorbed on the hand when at least one of the hand and the substrate moves in a direction close to the hand and the substrate, based on the tilt. A lithography device that forms a pattern on a substrate, comprising: a substrate transport system as described in any one of claims 1 to 11 for transporting the substrate; and an exposure unit for performing an exposure process on the substrate. The lithography device of claim 12 has a projection optical system that projects the original pattern onto the substrate transported by the substrate transport system. A method for manufacturing an article comprises: a formation procedure for forming a pattern on a substrate using a lithography apparatus having a substrate conveying system; and a procedure for manufacturing an article from the substrate on which the pattern is formed in the formation procedure; the substrate conveying system is a substrate conveying system for conveying the substrate to a predetermined position, and comprises: a hand for adsorbing and holding the substrate; a sensor for measuring the pressure between the hand and the substrate; and a control unit for obtaining, based on the measurement result of the sensor, the time taken for adsorption of the substrate that changes due to the change in the inclination of the driving axis driving the hand, and determining whether to derive the relative movement amount of the hand and the substrate until the substrate is adsorbed by the hand when at least one of the hand and the substrate is moved in a direction in which the hand and the substrate are close to each other, according to the time taken for adsorption of the substrate.