Method for adjusting substrate processing apparatus, substrate processing apparatus, and method for manufacturing article

Abstract

This method for adjusting a substrate processing apparatus includes: (a) a step for adjusting the temperature of a substrate by setting a temporary temperature as the set temperature of a temperature adjustment unit for adjusting the temperature of the substrate; (b) a step for obtaining a first measurement value by conveying the substrate from the temperature adjustment unit to a substrate stage by means of a conveyance mechanism and measuring a mark on the substrate in a state in which the substrate is chucked by a substrate chuck on the substrate stage; and (c) a step for obtaining a second measurement value by performing a re-chucking operation including de-chucking and re-chucking of the substrate by the substrate chuck, and then measuring the mark on the substrate. Steps (a)-(c) are repeated for each of the plurality of temporary temperatures, and the set temperature of the temperature adjustment unit is determined on the basis of the first measurement values and the second measurement values obtained by repeating steps (a)-(c).

Description

METHOD FOR ADJUSTING SUBSTRATE PROCESSING APPARATUS, ... AND METHOD FOR MANUFACTURING ARTICLE

[0001] The present invention relates to a method for adjusting a substrate processing apparatus, a substrate processing apparatus, and a method for manufacturing an article.

[0002] In exposure tools and metrology tools used in semiconductor manufacturing, substrate positioning and temperature adjustment are generally performed before the substrate is transferred to the stage where processing will take place. In recent years, with the miniaturization and high integration of devices, there has been an increasing demand for improved device alignment and overlay accuracy. This has led to the need for even stricter control of substrate temperature.

[0003] Patent document 1 describes that when transporting a substrate to a processing space, in order to reduce the occurrence of temperature distribution on the substrate due to contact with the substrate, the temperature of the substrate is measured and the temperatures of the hand part of the transport robot and the holding part of the alignment unit are controlled to match the temperature of the substrate.

[0004] JP 2014-036070 A

[0005] To improve alignment accuracy and overlay accuracy, it is necessary to adjust the substrate temperature before transfer, taking into consideration the substrate temperature after transfer to the stage where processing will be performed.

[0006] The present invention has been made in response to the recognition of the above-mentioned problems, and provides, for example, a method for adjusting a substrate processing apparatus to perform a substrate processing operation satisfactorily.

[0007] According to one aspect of the present invention, there is provided a method for adjusting a substrate processing apparatus for processing a substrate, the method comprising the steps of: (a) adjusting the temperature of the substrate by setting a set temperature of a temperature adjustment unit that adjusts the temperature of the substrate to a virtual temperature; (b) transporting the substrate from the temperature adjustment unit to a substrate stage by a transport mechanism, and measuring a mark on the substrate while the substrate is chucked by a substrate chuck on the substrate stage to obtain a first measurement value; and (c) performing a re-chucking operation that includes de-chucking and re-chucking the substrate by the substrate chuck, and then measuring the mark on the substrate to obtain a second measurement value, wherein steps (a) to (c) are repeated for each of a plurality of virtual temperatures, and the set temperature of the temperature adjustment unit is determined based on the first measurement value and the second measurement value obtained by repeating steps (a) to (c).

[0008] According to the present invention, for example, a method for adjusting a substrate processing apparatus for performing a substrate processing operation satisfactorily can be provided.

[0009] Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which the same or similar elements are designated by the same reference numerals.

[0010] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments of the present invention, and are used, together with the description, to explain the principles of the present invention. A diagram showing the configuration of an exposure apparatus according to a first embodiment. A diagram showing the configuration of an exposure apparatus according to the first embodiment. A diagram explaining the operation of changing over a substrate on a substrate stage. A diagram explaining the operation of changing over a substrate on a substrate stage. A diagram explaining the operation of changing over a substrate on a substrate stage. A diagram explaining the operation of changing over a substrate on a substrate stage. A flowchart showing a method of determining the optimal set temperature of a temperature adjustment unit. A diagram illustrating an example of a sample shot area on a substrate. A diagram illustrating an example of a sample shot area on a substrate. A flowchart showing the procedure for calculating the optimal set temperature of a temperature adjustment unit. A flowchart showing the procedure for calculating the optimal set temperature of a temperature adjustment unit. A diagram showing the configuration of a measurement apparatus according to a second embodiment. A diagram showing the configuration of a measurement apparatus according to the second embodiment.

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0012] In the embodiment, an example will be described in which the method for adjusting a substrate processing apparatus that processes a substrate is applied. The substrate processing apparatus may be, for example, a substrate processing apparatus used to form a pattern on a substrate. Such a substrate processing apparatus may be, for example, any of a lithography apparatus (an exposure apparatus, an imprint apparatus, a charged particle beam lithography apparatus, etc.), a metrology apparatus (a pre-alignment metrology apparatus, etc.), and an inspection apparatus (an overlay inspection apparatus, etc.).

[0013] First Embodiment In the following, to provide a specific example, an example will be described in which a substrate processing apparatus is configured as an exposure apparatus, which is an example of a lithography apparatus. FIG. 1A is a schematic diagram showing the configuration of an exposure apparatus 100 in the first embodiment. In this specification and the drawings, directions are indicated in an XYZ coordinate system, with the horizontal plane being the XY plane. Generally, a substrate 10, which is an object to be exposed, is placed on a substrate stage 50 so that its surface is parallel to the horizontal plane (XY plane). Therefore, hereinafter, the directions orthogonal to each other in a plane along the substrate mounting surface of the substrate stage 50 are referred to as the X-axis and Y-axis, and the direction perpendicular to the X-axis and Y-axis is referred to as the Z-axis. Furthermore, hereinafter, the directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are referred to as the X-direction, Y-direction, and Z-direction, respectively, and the directions of rotation around the X-axis, Y-axis, and Z-axis are referred to as the θX-direction, θY-direction, and θZ-direction, respectively.

[0014] The exposure apparatus 100 is a lithography apparatus used in a lithography process, which is a manufacturing process for devices such as semiconductor elements and liquid crystal display elements, and forms a pattern on a substrate 10 .

[0015] Control unit 90 is configured by, for example, a computer (information processing device) including a CPU and memory. Control unit 90 operates exposure apparatus 100 by comprehensively controlling each part of exposure apparatus 100 in accordance with a program stored in a storage unit inside or outside the apparatus.

[0016] The illumination optical system 6 shapes the light from the light source unit 5 into a predetermined shape optimal for exposure and uniformly illuminates the reticle 9, which is an original. The reticle 9 is made of, for example, quartz. A pattern (circuit pattern) to be transferred to a substrate 10 is formed on the reticle 9. The reticle stage 8 holds the reticle 9 via a reticle chuck and is connected to a reticle drive mechanism (not shown). The reticle drive mechanism includes a linear motor and the like, and drives the reticle stage 8 in the X, Y, Z, θX, θY, and θZ directions to move the reticle 9 held by the reticle stage 8 to a desired position. The projection optical system 7 functions to image light from an object plane onto an image plane. The projection optical system 7 projects light (diffracted light) that has passed through the pattern of the reticle 9 onto the substrate 10, forming an image of the pattern of the reticle 9 on the substrate. The substrate 10 is coated with a photoresist. The substrate 10 is a processing object onto which the pattern image of the reticle 9 is transferred, and includes a wafer, a liquid crystal substrate, or other processing target substrate. The substrate stage 50 holds the substrate 10 via a substrate chuck 51 and is connected to a substrate driving mechanism. A temperature control medium (e.g., a fluid such as coolant oil or cooling water) flow mechanism configured on the substrate stage 50 adjusts the surface of the substrate chuck 51 to a desired uniform temperature. The substrate driving mechanism includes a linear motor and the like, and can move the substrate 10 held on the substrate stage 50 by driving the substrate stage 50 in the X, Y, Z, θX, θY, and θZ directions. The positions of the reticle stage 8 and the substrate stage 50 are monitored, for example, by a six-axis laser interferometer and controlled by a control unit 90. The alignment scope 80 is a measurement unit that measures alignment marks on the substrate 10 while the substrate 10 is held on the substrate stage 50. When performing overlapping exposure on the target layer, the position of the substrate 10 is measured prior to exposure.

[0017] 1B, the flow from loading to unloading of the substrate 10 will be described in detail. The exposure apparatus 100 is connected to a coating and developing apparatus 1 (coater-developer) that has the functions of coating a substrate with resist and developing the exposed substrate. The connection between the exposure apparatus 100 and the coating and developing apparatus 1 is usually called an in-line connection.

[0018] When transporting a substrate from the coating and developing apparatus 1 to the exposure apparatus 100, the substrate 10 is transported to a first alignment apparatus 20, which serves as an interface between the interior of the exposure apparatus 100 and the coating and developing apparatus 1. The first alignment apparatus 20 includes a holder 21, which holds the substrate 10 and can rotate it in the θZ direction. The holder 21 holds the center of the substrate 10 from below, for example. The first alignment apparatus 20 aligns the substrate 10, for example, so that the reference position of the substrate 10 faces a predetermined direction. For example, a notch or an orientation flat is formed at the reference position of the substrate 10, and the reference position can be identified by detecting this. Hereinafter, it is assumed that a notch is formed at the reference position. The predetermined direction refers to a direction in which the notch of the substrate 10 is located within the detection range of the second alignment apparatus 30, described below, when the substrate 10 is transported to the second alignment apparatus 30.

[0019] The exposure apparatus 100 includes a transport mechanism 40 that holds and transports the substrate 10 with a hand. In this embodiment, the transport mechanism 40 can include a first transport robot 41, a second transport robot 42, and a third transport robot 43. The first transport robot 41, the second transport robot 42, and the third transport robot 43 include hand units 411, 421, and 431, respectively, and transport the substrate by suction holding using suction units (not shown) provided on the hand units.

[0020] After the notch alignment is completed by the first alignment device 20, the substrate 10 is transferred to the second alignment device 30 by the first transfer robot 41. The second alignment device 30 may include a shape detection sensor that detects the outer peripheral shape and notch of the substrate, an alignment stage that positions the substrate in the XY and θZ directions, and lift pins 32 for transferring the substrate. The second alignment device 30 also has a temperature control function that adjusts the substrate to a predetermined temperature, and this temperature control function may be achieved by a temperature control unit 31. Note that although FIG. 1B shows three lift pins 32, the number of lift pins 32 is not limited to a specific number as long as the purpose of stably holding the substrate is achieved.

[0021] In the second alignment device 30, lift pins 32 protruding upward from the substrate holding surface of the temperature adjustment unit 31 receive the substrate 10 from the hand unit 411 of the first transport robot 41. Thereafter, the lift pins 32 move downward (in the −Z direction), so that the substrate 10 is placed on the substrate holding surface of the temperature adjustment unit 31. The temperature adjustment unit 31 holds the substrate by suction and adjusts the temperature of the substrate 10 to a predetermined temperature.

[0022] The position of the substrate 10 held by suction on the temperature adjustment unit 31 is measured by a shape detection sensor. The control unit 90 controls the positioning of the alignment stage in the XY and θZ directions so that the output of the shape detection sensor becomes a predetermined output. Here, the predetermined output means an output such that the alignment mark on the substrate is within the detection range of the alignment scope 80 when the substrate is transported to the substrate stage 50 (described later). As described above, in the second alignment device 30, temperature adjustment and positioning of the substrate are performed in parallel.

[0023] After the alignment and temperature adjustment by the second alignment device 30 is completed, the substrate 10 is transferred from the temperature adjustment unit 31 to the lift pins 32 by the lift pins 32 moving upward (in the +Z direction). The substrate 10 supported by the lift pins 32 is transferred to the second transport robot 42. The second transport robot 42 transports the substrate 10 to above the supply position LP. The substrate stage 50 is driven to the supply position LP. The lift pins 52 are driven upward (in the +Z direction) so as to protrude from the surface of the substrate chuck 51, and receive the substrate 10 from the second transport robot 42. The second transport robot is then driven in the -Y direction and retracts from the supply position LP. The lift pins 52 are driven downward (in the -Z direction), thereby transferring the substrate 10 to the substrate chuck 51. The substrate chuck 51 suction-holds (chucks) the substrate 10. The method of chucking the substrate by the substrate chuck 51 may be a vacuum suction method or an electrostatic adsorption method. Here, it is assumed that the vacuum suction method is adopted as the method of chucking the substrate by the substrate chuck 51. In order to improve productivity and shorten the substrate transfer time, it is common to start vacuum suction by the substrate chuck 51 while (or before) the lift pins 52 are being driven in the −Z direction.

[0024] The substrate 10 held by the substrate stage 50 is transported directly below the alignment scope 80. The alignment scope 80 is a detection unit that detects the marks on the substrate that are mounted on the substrate chuck. The alignment scope 80 captures an image of an alignment mark provided on the substrate, for example, in a scribe line, and a control unit 90 determines the position (misalignment) of the shot area on the substrate. The control unit 90 drives the substrate stage 50 based on the determined position (X position, Y position, Z position, θZ position). After the misalignment has been corrected on the substrate stage 50, the substrate 10 is transported by the substrate stage 50 to below the projection optical system 7 that projects a mask pattern onto the substrate 10, and is exposed via the projection optical system 7.

[0025] When exposure is complete, the substrate stage 50 is driven to a recovery position ULP. Here, the substrate 10 is recovered by the third transfer robot 43 and transferred to the recovery table 60. The substrate 10 transferred to the recovery table 60 is then recovered by the first transfer robot 41 and transferred to the unloading table 22, which forms an interface with the coating and developing apparatus 1. The substrate 10 on the unloading table 22 is transferred to the coating and developing apparatus 1 by a substrate transfer robot (not shown). The coating and developing apparatus 1 performs a development process on the substrate 10.

[0026] Incidentally, the first transport robot 41, the second transport robot 42, and the third transport robot 43 are each provided with multiple heat sources, such as drive motors. The heat generated by these heat sources during operation is transferred to the hand units 411, 421, and 431 that hold the substrate by suction, causing the temperature to rise relative to the ambient temperature. In particular, even if the temperature control unit 31 of the second alignment device 30 controls the temperature to be uniform across the substrate surface, when the substrate is held by the hand unit 421 of the second transport robot 42, temperature variations occur between the area of ​​the substrate that comes into contact with the hand unit 421 and its surrounding area. From the perspectives of overlay accuracy and alignment accuracy, it is desirable to start the operation of transferring the substrate to the substrate stage 50 while maintaining a uniform temperature across the substrate surface.

[0027] On the other hand, as described above, the in-plane temperature of the substrate chuck 51 is adjusted to a desired uniform temperature by a mechanism configured in the substrate stage 50 that circulates a temperature-controlling medium (e.g., a fluid such as coolant oil or cooling water). Therefore, even if the transfer operation is initiated in a state in which the in-plane temperature uniformity of the substrate 10 is disrupted and temperature irregularities occur due to contact with the hand unit 421, the final temperature and uniformity of the substrate 10 depend on the substrate chuck 51. However, as described above, in order to shorten the substrate transfer time with the aim of improving productivity, vacuum suction of the substrate chuck 51 is initiated while (or prior to) driving the lift pins 52 in the -Z direction. Therefore, suction is completed before the temperature of the substrate 10 adapts to the temperature of the substrate chuck 51, i.e., while the temperature uniformity is disrupted due to contact with the hand unit 421. As a result, deformation occurs in the arrangement of multiple shot areas across the entire substrate and in the shape of the shot areas.

[0028] Furthermore, in aligning a substrate in exposure apparatus 100, the first alignment device 20 and second alignment device 30 rotate the substrate based on the outer shape of the substrate to adjust the position of the substrate. Next, the substrate stage 50 measures the shot arrangement of the substrate, and rotates the substrate based on the measurement results to adjust the position of the substrate more precisely. After that, fine alignment such as global alignment is performed.

[0029] In such substrate alignment, the substrate position is adjusted by the first alignment device 20 and the second alignment device 30. However, after this adjustment, measurement of the substrate arrangement using the alignment scope 80 may result in the amount of substrate rotation adjusted by the substrate stage 50 exceeding the rotation stroke of a single rotation operation of the substrate stage 50. In such a case, the substrate stage 50 is required to transfer the substrate between the lift pins 52 that hold the substrate 10 and the substrate chuck 51 that adsorbs the substrate 10. Specifically, from a state in which the substrate 10 is adsorbed by the substrate chuck 51 as shown in FIG. 2A , the substrate adsorption is released and the lift pins 52 are driven in the +Z direction so as to protrude from the surface of the substrate chuck 51 as shown in FIG. 2B , thereby separating the substrate 10 from the substrate chuck 51. Then, as shown in FIG. 2C , the substrate chuck 51 is rotated by the rotation mechanism of the substrate stage 50, and the lift pins 52 are again driven in the −Z direction to transfer the substrate 10 to the substrate chuck 51 and hold it by adsorption. 2D, the rotation amount is returned to the original amount by the rotation mechanism of the substrate stage 50. This operation can be repeated until the deviation in the rotation direction of the shot arrangement while the substrate 10 is held by the substrate stage 50 falls within the allowable range.

[0030] In this way, when the substrate 10 is re-gripped on the substrate stage 50, the temperature of the substrate 10 becomes accustomed to the temperature of the substrate chuck 51 due to contact between the substrate 10 and the substrate chuck 51. Therefore, after the re-gripping operation, the substrate suction is completed in a state where the temperature unevenness of the substrate 10 caused by contact with the hand unit 421 described above is resolved. Therefore, whether or not the substrate is re-gripped on the substrate stage 50 occurs can cause differences in the shape of the arrangement of the multiple shot areas on the entire substrate and deformation of the shapes of the shot areas, which can result in a decrease in overlay accuracy and alignment accuracy.

[0031] Therefore, it will be understood that the set temperature of the temperature adjustment unit 31 must be determined so as not to deform the shape of the arrangement of multiple shot areas across the entire substrate or the shapes of the shot areas, regardless of whether or not a substrate re-holding operation occurs on the substrate stage 50. Below, a procedure for determining the optimal set temperature of the temperature adjustment unit 31 will be described as a method for adjusting the exposure apparatus, with reference to FIG.

[0032] In S201, the control unit 90 initializes a variable n for counting the number of processing loops (n=0). In S202, the control unit 90 controls the transport mechanism 40 to transport the substrate 10 to the temperature adjustment unit 31. The substrate 10 can be transported from the coating and developing apparatus 1, but as will be seen in the subsequent flow, the procedure for determining the set temperature of the temperature adjustment unit 31 does not require resist coating, exposure, or development, so transport can begin from the substrate carrier 70 built into the exposure apparatus 100. The substrate carrier 70 can be, for example, a container capable of containing multiple substrates, known as a FOUP (Front Opening Unified Pod).

[0033] In S203, the control unit 90 sets the set temperature of the temperature adjustment unit 31 to a virtual temperature. The default set temperature of the temperature adjustment unit 31 can be, for example, 23.0°C, but in the adjustment procedure of this embodiment, the set temperature of the temperature adjustment unit 31 is described as being adjustable in 0.02°C increments within a range from 22.90°C to 23.10°C. In one example, in S203 at the start of adjustment, the control unit 90 sets the virtual temperature of the temperature adjustment unit 31 to 22.90°C and adjusts the temperature of the substrate 10 (step (a)).

[0034] In S204, the control unit 90 controls the transport mechanism 40 to transport the substrate 10 to the substrate stage 50. As described above, the substrate 10 is placed on the substrate chuck 51 via the lift pins 52. The substrate chuck 51 adsorbs and holds the placed substrate 10.

[0035] Alignment marks measurable by the alignment scope 80 are formed on the substrate 10 for each of the multiple shot areas. In S205, the control unit 90 performs a first measurement using the alignment scope 80 to measure the alignment marks of the sample shot areas while the substrate 10 is chucked by the substrate chuck 51, thereby obtaining a first measurement value (step (b)). The first measurement value is, for example, the difference between the design coordinates and the actual coordinates of the alignment marks of the sample shot areas. As shown in FIG. 4A , all of the multiple shot areas on the substrate may be set as sample shot areas. Alternatively, as shown in FIG. 4B , a portion of the multiple shot areas selected from the multiple shot areas may be set as sample shot areas. The number and positions of the sample shot areas are preferably set at positions where array lattice distortion due to thermal deformation of the substrate 10 can be observed.

[0036] Next, step (c) is performed. In step (c), a re-chucking operation is performed in S207 and measurement is performed in S208. In S207, the control unit 90 causes the substrate chuck 51 to dechuck (release suction) the substrate 10 and then re-chuck it. This is called a "re-chucking operation." The de-chucking of the substrate 10 is performed by turning off the vacuum suction of the substrate chuck 51. This re-chucking operation simulates the substrate re-holding operation described above. In other words, this re-chucking operation is expected to eliminate temperature variations in the substrate 10 caused by contact with the transport mechanism 40 (hand unit 421). At this time, in addition to turning off the vacuum suction, the lift pins 52 may be protruded in the +Z direction from the substrate chuck 51 to reliably separate the substrate 10 from the substrate chuck 51. That is, the rechucking operation may include dechucking the substrate, separating the substrate from the substrate chuck after dechucking, and rechucking the substrate with the substrate chuck after separation.

[0037] In S208, control unit 90 uses alignment scope 80 to measure the alignment marks in the sample shot areas of substrate 10 that has been re-chucked by substrate chuck 51, and obtains second measurement values. Similar to the first measurement values, the second measurement values ​​are, for example, the differences between the design coordinates and actual coordinates of the alignment marks in the sample shot areas. Note that the number and positions of the sample shot areas at this time are the same as those in S205.

[0038] In S209, the control unit 90 increments the value of the variable n for counting the number of processing loops by 1 (n = n + 1). In S210, the control unit 90 determines whether measurements at all virtual temperatures have been completed. "All virtual temperatures" refers to all virtual temperatures set in 0.02°C increments within the set temperature range of 22.90°C to 23.10°C, as described as an example in S203. In S210, the control unit 90 may determine whether measurements at all virtual temperatures have been completed by determining whether the value of the variable n has reached the number of processing loops N calculated from the set temperature range and the temperature increments. If the virtual temperature of the temperature adjustment unit 31 is initially set to 22.90°C, the lower end of the set temperature range, in S210, it is determined that measurements are incomplete, and the process returns to S202. Thereafter, in S202, the substrate 10 is transported to the temperature adjustment unit 31, and in S203, the temporary temperature of the temperature adjustment unit 31 is set to 22.92° C. and temperature adjustment is performed, and then the procedures from S204 onward are performed.

[0039] By this processing loop, the above-described steps (a), (b), and (c) are repeated for each of the plurality of virtual temperatures. Once the first measurement value and the second measurement value have been obtained for all of the plurality of virtual temperatures, the processing proceeds to S211.

[0040] In S211, the control unit 90 controls the transport mechanism 40 to unload the substrate 10. For example, if the substrate 10 is transported from the substrate carrier 70 in S202, the substrate 10 is unloaded to the substrate carrier 70 in S211.

[0041] In S212, the control unit 90 calculates (determines) the optimal temperature of the temperature adjustment unit 31 based on the first measurement values ​​acquired for each of the multiple virtual temperatures and the second measurement values ​​obtained by performing the second measurement including the re-chucking operation. A specific example of the calculation procedure for the optimal temperature of the temperature adjustment unit 31 will be described with reference to FIG.

[0042] In this embodiment, the first measurement value and the second measurement value each include a plurality of measurement values ​​obtained by measuring the alignment marks in each of a plurality of sample shot areas on the substrate. In S2121, the control unit 90 performs a statistical calculation on the second measurement value to remove linear components (shift, magnification, and rotation). Furthermore, the control unit 90 performs a statistical calculation on the first measurement value for each virtual temperature to remove linear components.

[0043] In S2122, the control unit 90 calculates, for each virtual temperature, the standard deviation σ of the difference between the first measurement value and the second measurement value after the linear component has been removed. Here, for example, 3σ of the difference between the two (the difference 3σ) is calculated. Figure 5B shows a graph with the virtual temperature (set temperature) of the temperature adjustment unit 31 on the horizontal axis and the difference 3σ on the vertical axis.

[0044] In S2123, the control unit 90 determines the optimal temperature (temperature to be set) for the temperature adjustment unit 31 based on the standard deviation for each virtual temperature. For example, the control unit 90 determines the set temperature of the temperature adjustment unit 31 that minimizes the difference 3σ by statistical calculation such as the least squares method. The dashed line in the graph of FIG. 5B is an approximation curve determined by the least squares method. If the difference 3σ is δ and the set temperature of the temperature adjustment unit 31 is T, the model formula used in the least squares method can be expressed, for example, by the following formula:

[0045] δ = aT ２ +bT+c where a, b, and c represent parameters of each term. From the above model formula of the least squares method, the set temperature Tmin of the temperature adjustment unit 31 at which the difference 3σ is minimum is expressed by the following formula.

[0046] Tmin=-b / (2a)

[0047] In the case of the graph of FIG. 5B, Tmin is determined to be 23.02°C.

[0048] 3 , in S213, the control unit 90 sets the calculated set temperature Tmin as the optimum temperature of the temperature adjustment unit 31, and completes the adjustment. Note that since the first measurement value and the second measurement value each consist of two values, X and Y, the difference 3σ is calculated as two values, 3σx and 3σy. Therefore, two values, Tminx and Tminy, are calculated for Tmin, and the temperature Tmin set as the optimum temperature of the temperature adjustment unit 31 can be, for example, the average value of Tminx and Tminy.

[0049] In this manner, in this embodiment, the optimum set temperature of the temperature adjustment unit 31 is determined based on the following alignment mark measurement values ​​obtained at multiple virtual temperatures of the temperature adjustment unit 31: (a) Measurement value (first measurement value) of the alignment mark in the sample shot area of ​​the substrate 10 transported onto the substrate stage and held by the substrate chuck 51, (b) Measurement value (second measurement value) of the alignment mark in the sample shot area of ​​the substrate 10 after the re-chucking operation by the substrate chuck 51 has been performed.

[0050] This reduces the difference in the shape of the arrangement of multiple shot areas across the substrate and the deformation of the shot area shapes depending on whether or not the substrate is being re-gripped on the substrate stage 50, improving overlay accuracy and alignment accuracy.

[0051] The plurality of virtual temperatures is preferably at least three different virtual temperatures, because the approximation curve can be calculated with high accuracy by the least squares method. However, if the approximate shape of the approximation curve is known, the plurality of virtual temperatures may be two different virtual temperatures.

[0052] Second Embodiment An example in which a substrate processing apparatus is configured as a measuring apparatus will be described below. Figures 6A and 6B are schematic diagrams showing the configuration of a measuring apparatus 200 in the second embodiment.

[0053] The measuring apparatus 200 may be, for example, an alignment measuring apparatus that measures the position of a mark formed on a reference layer (target layer) of the substrate. The substrate 10 is a measurement object for which the shape of the arrangement of multiple shot areas across the entire substrate and the shapes of the shot areas are measured by the measuring apparatus 200, and is, for example, a substrate used to manufacture devices such as semiconductor elements and liquid crystal display elements. Specifically, it includes wafers, glass substrates, other substrates to be processed, and the like.

[0054] Mark position measurement is performed by capturing an image of the mark using an alignment scope 80. To achieve high-precision alignment even if distortion (substrate distortion) occurs in the arrangement of shot areas during device manufacturing, it is necessary to measure the positions of a large number of alignment marks on the substrate. However, if the positions of a large number of alignment marks are measured using the alignment scope 80 of the exposure apparatus 100, the alignment measurement time increases and the productivity of the exposure apparatus decreases. For this reason, a technique is known in which measurements are performed in advance using a measurement apparatus 200 separate from the exposure apparatus 100, and exposure is performed taking the measurement results into account.

[0055] The measuring device 200 is connected to a cassette station 2 configured to be able to place a plurality of substrate cassettes 71. The substrate cassettes 71 may be, for example, a Front Opening Unified Pod (FOUP), and the cassette station 2 may be, for example, an Equipment Front End Module (EFEM). The connection between the measuring device 200 and the cassette station 2 is usually called an inline connection.

[0056] The configuration on the substrate transport path inside the measurement apparatus 200 is the same as the configuration on the substrate transport path inside the exposure apparatus 100. The two major differences are that the process performed on the substrate stage 50 is mark measurement rather than exposure, and the source and destination of the substrate is cassette station 2 rather than coating and developing apparatus 1. Therefore, in the flow from substrate load to substrate unload in the measurement apparatus 200, the only place where exposure apparatus 100 performs exposure processing in the first embodiment is measurement processing using an alignment scope. In addition, the source and destination of the substrate is cassette station 2 rather than coating and developing apparatus 1.

[0057] Therefore, the method of optimally adjusting the set temperature of the temperature adjustment unit 31 described in the first embodiment can also be applied to the measurement apparatus 200. By applying this method to the measurement apparatus 200, differences in the shape of the arrangement of multiple shot areas across the entire substrate and the deformation of the shapes of the shot areas due to whether or not a substrate re-holding operation occurs on the substrate stage 50 are reduced, improving measurement accuracy.

[0058] <Embodiment of Article Manufacturing Method> The article manufacturing method according to an embodiment of the present invention is suitable for manufacturing articles such as microdevices, such as semiconductor devices, and elements having microstructures. The article manufacturing method according to this embodiment may include a forming step of forming a master pattern on a substrate using the substrate processing apparatus described above, and a processing step of processing the substrate on which the pattern has been formed in the forming step. Furthermore, this article manufacturing method may include other well-known processes (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method according to this embodiment is advantageous over conventional methods in at least one of article performance, quality, productivity, and production cost.

[0059] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention.

[0060] This application claims priority based on Japanese Patent Application No. 2024-059629, filed April 2, 2024, the entire contents of which are incorporated herein by reference.

Claims

1. A method for adjusting a substrate processing apparatus that processes substrates, comprising: (a) a step of adjusting the temperature of the substrate by setting the set temperature of a temperature adjustment unit that adjusts the temperature of the substrate to a virtual temperature; (b) a step of transporting the substrate from the temperature adjustment unit to a substrate stage by a transport mechanism, and measuring a mark on the substrate while the substrate is chucked by a substrate chuck on the substrate stage to obtain a first measurement value; and (c) a step of performing a re-chucking operation that includes de-chucking and re-chucking the substrate by the substrate chuck, and then measuring the mark on the substrate to obtain a second measurement value; wherein steps (a) to (c) are repeated for each of a plurality of virtual temperatures, and the set temperature of the temperature adjustment unit is determined based on the first measurement value and the second measurement value obtained by repeating steps (a) to (c).

2. The adjustment method of claim 1, wherein the rechucking operation includes dechucking the substrate, separating the substrate from the substrate chuck after the dechucking, and rechucking the substrate with the substrate chuck after the separation.

3. The adjustment method according to claim 1 or 2, characterized in that each of the first measurement value and the second measurement value includes a plurality of measurement values ​​obtained by measuring alignment marks in each of a plurality of sample shot areas of the substrate, and the step of determining the set temperature of the temperature adjustment unit includes the steps of: performing a statistical operation on the second measurement value to remove linear components, and performing a statistical operation on the first measurement value for each virtual temperature to remove linear components; calculating, for each virtual temperature, the standard deviation of the difference between the first measurement value and the second measurement value after the linear components have been removed; and determining the set temperature of the temperature adjustment unit based on the standard deviation for each virtual temperature.

4. The adjustment method according to claim 3, wherein in the determination step, the set temperature of the temperature adjustment unit that minimizes 3σ when the standard deviation is σ is determined using the least squares method.

5. The adjusting method according to any one of claims 1 to 4, wherein the plurality of virtual temperatures are at least three different virtual temperatures.

6. A substrate processing apparatus for processing a substrate, comprising: a temperature control unit for controlling the temperature of the substrate; a substrate chuck for chucking the substrate on a substrate stage; a transport mechanism for transporting the substrate from the temperature control unit to the substrate chuck; a detection unit for detecting a mark on the substrate on the substrate chuck; and a control unit, wherein the control unit is configured to perform the following steps: (a) setting the set temperature of the temperature control unit to a virtual temperature to control the temperature of the substrate; (b) transporting the substrate from the temperature control unit to the substrate chuck by the transport mechanism, and measuring the mark on the substrate using the detection unit while the substrate is chucked by the substrate chuck to obtain a first measurement value; and (c) dechucking and re-chucking the substrate by the substrate chuck, and then measuring the mark on the substrate using the detection unit to obtain a second measurement value; and the steps (a) to (c) are repeated for each of a plurality of virtual temperatures, and the set temperature of the temperature adjustment unit is determined based on the first measurement value and the second measurement value obtained by repeatedly performing the steps (a) to (c).

7. The substrate processing apparatus according to claim 6, wherein the substrate processing apparatus is a lithography apparatus that forms a pattern on the substrate.

8. The substrate processing apparatus according to claim 6, wherein the substrate processing apparatus is a measurement apparatus that measures the mark on the substrate using the detection unit.

9. A method for manufacturing an article, comprising the steps of: forming a pattern on a substrate using the substrate processing apparatus according to claim 7; and processing the substrate on which the pattern has been formed; and manufacturing an article from the processed substrate.

Images