Determination method, information processing apparatus, exposure apparatus, exposure method, and method for manufacturing article

Abstract

The invention provides a determination method, an information processing apparatus, an exposure apparatus, an exposure method, and an article manufacturing method. A determination method for determining a baseline correction amount of a baseline indicating a distance between an optical axis of a first measurement instrument that detects a mark via a projection optical system that projects light from an original plate onto a substrate and an optical axis of a second measurement instrument that does not detect the mark via the projection optical system, the determination method comprising: a first step for determining a baseline correction amount of the baseline; acquiring a reference baseline from a first number of detection results by the first measurement instrument and the second measurement instrument; a second step for acquiring a base line (Mn) from the detection results of a second number of times less than the first number of times by the first measurement instrument and the second measurement instrument with respect to the nth (n is an integer of 1 or more) lot; and a third step for determining a baseline correction amount (Xn) to be used in the nth batch on the basis of the reference baseline acquired in the first step and the baseline (Mn) acquired in the second step.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a determination method, an information processing apparatus, an exposure apparatus, an exposure method, and a manufacturing method of an article. BACKGROUND

[0002] As one of photolithography apparatuses used in a manufacturing process of a device such as a semiconductor element or a liquid crystal panel, there is an exposure apparatus that transfers a pattern of a master onto a substrate. In order to transfer the pattern of the master onto the substrate with high precision, it is required to perform alignment of the master and the substrate. Therefore, before the substrate is exposed, alignment measurement of detecting alignment marks provided to each of the master and the substrate and measuring positions of the alignment marks is performed.

[0003] In the alignment measurement, there are generally two measurement methods. One is a measurement method of detecting alignment marks of each of the master and the substrate via a projection optical system, which is called a through the mirror method. The other is a measurement method of detecting only the alignment marks of the substrate without via the projection optical system, which is called an off axis method. In the exposure apparatus, generally, an alignment scope that performs the alignment measurement in each of these methods is provided to be used in each role.

[0004] In order to perform the alignment measurement in the off axis method, it is necessary to perform the alignment measurement in the through the mirror method in advance. The reason is that a relative positional relationship, that is, a baseline, of a detected position (a projection position of the pattern of the master) obtained in the alignment measurement in the through the mirror method and a detected position obtained in the alignment measurement in the off axis method is required. Specifically, in the alignment measurement in the off axis method, it is necessary to use the baseline to correct the detected position obtained in the alignment measurement. In addition, the baseline can be measured with high precision by performing the mark detection in the through the mirror method and the mark detection in the off axis method a plurality of times.

[0005] On the other hand, in the exposure apparatus, it is known that due to heat generation caused by exposure light and driving of a stage, a temporal error occurs in a relationship between a master coordinate system and a substrate coordinate system, so that the baseline varies and is not a constant value. Therefore, in a case where the same baseline is continuously used, a decrease in exposure precision including overlay precision and the like (baseline drift) occurs, so it is necessary to measure the baseline again at a certain period.

[0006] By re-measuring the baseline, it is possible to ensure exposure accuracy, but this causes a reduction in productivity. Therefore, in Japanese Patent Application Publication No. 2006-344739 and Japanese Patent Application Publication No. 2005-64371, a technique for investigating the timing of updating the baseline in order to maintain productivity while ensuring exposure accuracy (i.e., in order to achieve both exposure accuracy and productivity) is proposed. In Japanese Patent Application Publication No. 2006-344739, a technique for independently performing mark detection in a through-lens method and mark detection in an off-axis method at necessary timings, respectively, to update the baseline is disclosed. In Japanese Patent Application Publication No. 2005-64371, a technique for updating the baseline only in the case where the baseline is changed, based on the correlation between heat caused by exposure light and the baseline is disclosed.

[0007] In addition, a technique for selectively using high-accuracy measurement using multiple mark detections and high-speed measurement using fewer mark detections as measurement of the baseline is also known. For example, first, high-accuracy measurement is performed to acquire the baseline, and reference data is generated. At a later measurement timing, only high-speed measurement is performed, and if a difference of not more than a tolerance occurs between the reference data, correction is performed using the reference data. On the other hand, if a difference of more than the tolerance occurs, it is determined that the amount of change (change over time) of the baseline is large, and reference data is regenerated by high-accuracy measurement. According to the above technique, in the case where the baseline changes greatly, high-accuracy measurement is performed, and in other cases, high-speed measurement is performed, so it is possible to ensure both exposure accuracy and productivity. SUMMARY

[0008] However, it is known that reproducibility cannot be guaranteed with respect to measurement results obtained by an alignment measurement instrument, for example, even in the case where the same mark is detected, a difference occurs in the measurement results thereof.

[0009] In a technique for selectively using high-accuracy measurement and high-speed measurement as measurement of the baseline, reproducibility of measurement results obtained by an alignment measurement instrument greatly affects exposure accuracy. In the above technique, if a difference between reference data and measurement results obtained in high-speed measurement is small, it is possible to ensure exposure accuracy by performing correction using the reference data. However, a difference occurs in measurement results obtained in high-speed measurement, so in practice, even in the case where the difference from the reference data is large, it can be erroneously recognized that the difference is small. In this case, reference data is not regenerated, and correction is performed using the original reference data, so exposure accuracy is reduced.

[0010] The present disclosure provides a technique suitable for determining a baseline correction amount.

[0011] As one aspect of this disclosure, the determination method is a method for determining a baseline correction amount representing the distance between the optical axes of a first measuring instrument and a second measuring instrument, wherein the first measuring instrument detects a mark via a projection optics system that projects light from the original onto the substrate, and the second measuring instrument does not detect the mark via the projection optics system. The determination method is characterized by having: a first step of obtaining a reference baseline from the detection results of a first number of tests using the first measuring instrument and the second measuring instrument; and a second step of obtaining a baseline M for the nth batch (n being an integer greater than or equal to 1) from the detection results of a second number of tests using the first measuring instrument and the second measuring instrument, which is less than the first number of tests. n ; and the third step, based on the reference baseline obtained in the first step and the baseline M obtained in the second step. n Determine the baseline correction amount X to be used in the nth batch. n .

[0012] Another aspect of the invention is a method for determining a baseline correction amount for a baseline representing the distance between the optical axes of a first measuring instrument and a second measuring instrument. The first measuring instrument detects a mark via a projection optics system that projects light from the original onto a substrate, while the second measuring instrument does not detect the mark via the projection optics system. This method is characterized by: a first step of obtaining a reference baseline from the detection results of a first number of tests using both the first and second measuring instruments; and a second step of obtaining a baseline M for the nth batch (n being an integer greater than or equal to 2) from the detection results of a second number of tests using both the first and second measuring instruments, which is less than the first number of tests. n ; and the third process, based on the baseline correction amount X of the (n-1)th batch. n-1 and the baseline M obtained in the second process n Determine the baseline correction amount X to be used in the nth batch. n The baseline correction amount X of the (n-1)th batch n-1 It is based on the reference baseline obtained in the first process, and the baselines M1 to M1 of each batch up to the (n-1)th batch obtained from the detection results of the second number of times using the first measuring instrument and the second measuring instrument. n-1 It was decided.

[0013] The information processing apparatus according to a further aspect of the present application is characterized by having a processing section that performs processing of deciding a baseline correction amount of a baseline that represents a distance between an optical axis of a first measuring instrument that detects a mark via a projection optical system that projects light from a master onto a substrate and an optical axis of a second measuring instrument that detects a mark without via the projection optical system, the processing section acquiring a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument, acquiring a baseline M n from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times, with respect to an n-th (n is an integer of 2 or more) batch, deciding a baseline correction amount X n in the n-th batch from the reference baseline and the baseline M n .

[0014] The information processing apparatus according to a further aspect of the present application is characterized by having a processing section that performs processing of deciding a baseline correction amount of a baseline that represents a distance between an optical axis of a first measuring instrument that detects a mark via a projection optical system that projects light from a master onto a substrate and an optical axis of a second measuring instrument that detects a mark without via the projection optical system, the processing section acquiring a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument, acquiring a baseline M n from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times, with respect to an n-th (n is an integer of 2 or more) batch, deciding a baseline correction amount X n-1 in the n-th batch from a baseline correction amount X n of an (n-1)-th batch and the baseline M n , the baseline correction amount X n-1 of the (n-1)-th batch being decided from the reference baseline and from baselines M1 to M n-1 that are acquired from the detection result of the second number of times of use of the first measuring instrument and the second measuring instrument.

[0015] An exposure apparatus according to a further aspect of the present application is an exposure apparatus that exposes a substrate with a mask, characterized by comprising: a projection optical system that projects light from the mask onto the substrate; a first measuring instrument that detects a mark via the projection optical system; a second measuring instrument that detects a mark without via the projection optical system; and a processing portion that performs processing of determining a baseline correction amount that indicates a distance between an optical axis of the first measuring instrument and an optical axis of the second measuring instrument, the processing portion acquiring a reference baseline from detection results of a first number of times of use of the first measuring instrument and the second measuring instrument, acquiring a baseline M n from detection results of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times, with respect to an n-th (n is an integer of 2 or more) batch, determining a baseline correction amount X n to be used in the n-th batch from the reference baseline and the baseline M n .

[0016] An exposure apparatus according to a further aspect of the present application is an exposure apparatus that exposes a substrate with a mask, characterized by comprising: a projection optical system that projects light from the mask onto the substrate; a first measuring instrument that detects a mark via the projection optical system; a second measuring instrument that detects a mark without via the projection optical system; and a processing portion that performs processing of determining a baseline correction amount that indicates a distance between an optical axis of the first measuring instrument and an optical axis of the second measuring instrument, the processing portion acquiring a reference baseline from detection results of a first number of times of use of the first measuring instrument and the second measuring instrument, acquiring a baseline M n from detection results of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times, with respect to an n-th (n is an integer of 2 or more) batch, determining a baseline correction amount X n-1 to be used in the n-th batch from a baseline correction amount X n of an (n-1)-th batch and the baseline M n , the baseline correction amount X n-1 of the (n-1)-th batch being determined from the reference baseline and from baselines M1 to M n-1 that are acquired from the detection results of the second number of times of use of the first measuring instrument and the second measuring instrument.

[0017] An exposure method according to a further aspect of the present application is an exposure method of exposing a substrate via a master, characterized by comprising: a process of deciding a baseline correction amount of a baseline indicating a distance between an optical axis of a first measuring instrument that detects a mark via a projection optical system that projects light from the master to the substrate and an optical axis of a second measuring instrument that detects a mark without via the projection optical system; and a process of exposing the substrate while correcting a variation amount of the baseline using the baseline correction amount decided in the process of deciding, the process of deciding including: a first process of acquiring a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument; a second process of acquiring a baseline M n n (n is an integer of 2 or more) from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times; and a third process of deciding a baseline correction amount X n n to be used in the n-th batch, from the reference baseline acquired in the first process and the baseline M n n acquired in the second process.

[0018] An exposure method according to a further aspect of the present application is an exposure method of exposing a substrate via a master, characterized by comprising: a process of deciding a baseline correction amount of a baseline indicating a distance between an optical axis of a first measuring instrument that detects a mark via a projection optical system that projects light from the master to the substrate and an optical axis of a second measuring instrument that detects a mark without via the projection optical system; and a process of exposing the substrate while correcting a variation amount of the baseline using the baseline correction amount decided in the process of deciding, the process of deciding including: a first process of acquiring a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument; a second process of acquiring a baseline M n n from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument that is less than the first number of times; and a third process of deciding a baseline correction amount X n-1 n to be used in the n-th batch, from a baseline correction amount X n n-1 of a (n-1)-th batch and the baseline M n n acquired in the second process, the baseline correction amount X n-1 n-1 of the (n-1)-th batch being decided from the reference baseline acquired in the first process and from baselines M1~M n-1 n-1 of respective batches up to the (n-1)-th batch acquired from the detection result of the second number of times of use of the first measuring instrument and the second measuring instrument.

[0019] The manufacturing method of an article as a further other aspect of the present application is characterized by including: a step of exposing a substrate using the exposure apparatus; a step of developing the substrate after the exposure; and a step of manufacturing an article from the substrate after the development.

[0020] Further objects or other aspects of the present disclosure will become apparent from the following embodiments described with reference to the drawings.

[0021] According to the present disclosure, for example, a technique suitable for determining a baseline correction amount can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram showing a structure of an exposure apparatus as one aspect of the present embodiment.

[0023] Figure 2 is a flowchart for explaining a determination method of determining a baseline correction amount in the first embodiment.

[0024] Figure 3 is a flowchart for explaining a determination method of determining a baseline correction amount in the second embodiment. DETAILED DESCRIPTION

[0025] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not limiting on the invention covered by the claims. In the embodiments, a plurality of features are described; however, these features are not necessarily essential to the invention, and a plurality of features can be arbitrarily combined. Furthermore, in the drawings, the same or similar structures are denoted by the same reference numerals, and repetitive explanations are omitted.

[0026] Figure 1 is a schematic diagram showing a structure of an exposure apparatus 100 as one aspect of the present embodiment. The exposure apparatus 100 is a photolithography apparatus used in a photolithography process as a process for manufacturing an article including a device or the like, and forms a pattern on a substrate (wafer or wafer board) by exposing the substrate via a master (reticle or mask). The exposure apparatus 100 is embodied as an exposure apparatus for manufacturing a flat panel display (FPD) in the present embodiment. The exposure apparatus 100 projects a pattern of a master via a projection optical system to a substrate, and transfers the pattern of the master to the substrate.

[0027] In the present specification and the drawings, directions are represented with an XYZ coordinate system in which a direction perpendicular to a surface of a substrate (vertical direction) is set as a Z axis, and two directions parallel to a plane perpendicular to the Z axis and perpendicular to each other are set as an X axis and a Y axis. In addition, directions parallel to the X axis, the Y axis, and the Z axis in the XYZ coordinate system are set as an X direction, a Y direction, and a Z direction, respectively.

[0028] The exposure apparatus 100, as shown in FIG. 1, has an illumination optical system 1, an alignment measuring instrument 2, a projection optical system 4, a master plate stage 9, a substrate stage 10, a control section 11, and an off-axis measuring instrument 12. Figure 1

[0029] The illumination optical system 1, for example, includes optical elements such as lenses, mirrors, and the like, and illuminates the master plate 3 with light from a light source section (not shown). The light source section, for example, includes a mercury lamp, and an elliptical mirror. The illumination optical system 1, in the present embodiment, forms a predetermined shaped illumination area, and illuminates a portion of the master plate 3.

[0030] The projection optical system 4 projects a pattern (image) of the master plate 3 illuminated by the illumination optical system 1 onto the substrate 8. The projection optical system 4 can be composed of any of an equal magnification imaging optical system, a magnifying imaging optical system, or a reducing imaging optical system. The master plate 3 is disposed at a position of an object plane of the projection optical system 4, and the substrate 8 is disposed at a position of an image plane of the projection optical system 4.

[0031] The projection optical system 4, in the present embodiment, is composed of a reflection optical system including a concave mirror 5, a mirror 6, and a convex mirror 7. Light from the master plate 3 illuminated by the projection optical system 4 (image of the pattern of the master plate 3) is imaged on the substrate 8 in the projection optical system 4 via the mirror 6, the concave mirror 5, the convex mirror 7, the concave mirror 5, and the mirror 6. Further, the projection optical system 4 can be composed of a refractive optical system using mainly lenses, or a catadioptric optical system using lenses and mirrors, or a plurality of imaging optical systems.

[0032] The master plate stage 9 includes a master plate holding mechanism for holding the master plate 3, a position adjustment mechanism for adjusting the position of the master plate 3 in the X direction and the Y direction, a rotation adjustment mechanism for adjusting the rotation angle of the master plate 3 about the X axis and the Y axis, and the like.

[0033] The substrate stage 10 includes a substrate holding mechanism for holding the substrate 8, a position adjustment mechanism for adjusting the position of the substrate 8 in the X direction, the Y direction, and the Z direction, a rotation adjustment mechanism for adjusting the rotation angle of the substrate 8 about the X axis, the Y axis, and the Z axis, and the like.

[0034] The alignment measuring instrument 2 is a measuring instrument (first measuring instrument) for performing alignment measurement in a through-the-lens manner. The alignment measuring instrument 2 detects (images) alignment marks provided on the master plate 3 and the substrate 8, respectively, via the projection optical system 4, and measures the positions of the alignment marks.

[0035] ​The off-axis measuring instrument 12 is a measuring instrument (2nd measuring instrument) for performing alignment measurement in an off-axis manner. The off-axis measuring instrument 12 does not detect (image-capture) the alignment mark provided on the substrate 8 via the projection optical system 4 to measure the position of the alignment mark.

[0036] The control section 11 is constituted by, for example, a computer (information processing apparatus) including a CPU, a memory, and the like. The control section 11 generally controls each section of the exposure apparatus 100 in accordance with a program stored in a storage section or the like to cause the exposure apparatus 100 to operate. The control section 11 controls an exposure process of transferring the pattern of the original plate 3 to the substrate 8 and various processes associated with the exposure process.

[0037] For example, the control section 11 indirectly controls the positions and angles of the original plate 3 and the substrate 8 by driving the original plate stage 9 and the substrate stage 10 in accordance with the positions and angles measured by a position measuring instrument such as an interferometer or an encoder. In addition, the control section 11 calculates a baseline indicating the positional relationship of the alignment measuring instrument 2 and the off-axis measuring instrument 12 in accordance with the detection results of the alignment marks detected by the alignment measuring instrument 2 and the detection results of the alignment marks detected by the off-axis measuring instrument 12. Furthermore, the control section 11 calculates a correction amount for the position of the substrate stage 10 using the baseline and transfers the pattern of the original plate 3 to the substrate 8 while moving the original plate 3 and the substrate 8 in synchronization in a predetermined direction.

[0038] Here, the baseline refers to a movement distance (movement distance of the substrate stage 10) of the same mark required to detect the same mark in each of the alignment measuring instrument 2 and the off-axis measuring instrument 12 and obtain the same detection result. Therefore, in the present embodiment, the baseline is defined by the distance between the optical axis of the alignment measuring instrument 2 and the optical axis of the off-axis measuring instrument 12.

[0039] In the exposure apparatus 100, the baseline fluctuates due to heat generation caused by exposure light, driving of the substrate stage 10, and the like. Therefore, when the same baseline is continuously used, exposure accuracy including overlay accuracy and the like is reduced (baseline drift). Therefore, it is necessary to calculate a correction amount of the baseline, that is, determine the baseline correction amount, in accordance with the fluctuation of the baseline. Therefore, the determination method of the baseline correction amount will be described below.

[0040] <1st Embodiment>

[0041] Figure 2 is a flowchart for explaining the determination method of the baseline correction amount in the 1st embodiment. The above determination method is executed by the control section 11 generally controlling each section of the exposure apparatus 100. In this way, in the present embodiment, the control section 11 functions as a processing section that performs the process of determining the baseline correction amount.

[0042] In Sll, the control section 11 determines whether the task in execution is the initial task. If the task in execution is not the initial task, i.e., a task executed, the baseline reference value M is calculated base (baseline reference). Thus, it is possible to determine whether the task in execution is the initial task based on the presence or absence of the baseline reference value M base . In the case where the task in execution is the initial task, the processing proceeds to S12, and in the case where the task in execution is not the initial task, the processing proceeds to S13.

[0043] In S12, the control section 11 causes the alignment measuring instrument 2 and the off-axis measuring instrument 12 to perform high-precision measurement, and acquires the baseline reference value M base . Specifically, the detection of the alignment mark by the alignment measuring instrument 2 and the detection of the alignment mark by the off-axis measuring instrument 12 are performed a plurality of times (including the first time of the plurality of times), for example, 16 times, and respective detection results are acquired. Further, the baseline reference value M base is calculated based on the 16 detection results by the alignment measuring instrument 2 and the off-axis measuring instrument 12. In the present embodiment, the average of the 16 detection results by the alignment measuring instrument 2 and the off-axis measuring instrument 12 is used as the baseline reference value M base . In this way, by averaging the detection results of the plurality of times, the measurement errors of the alignment measuring instrument 2 and the off-axis measuring instrument 12 are averaged, and it is possible to make the baseline reference value M base close to the true value. However, in calculating the baseline reference value M base , it is not limited to averaging the detection results of the plurality of times, as long as it is possible to make the baseline reference value M base close to the true value. For example, it is also possible to use statistical processing (statistical method) to use a statistical value of the 16 detection results by the alignment measuring instrument 2 and the off-axis measuring instrument 12 as the baseline reference value M base . Further, it is also possible to use a method of standard deviation to calculate the baseline reference value M base based on the 16 detection results by the alignment measuring instrument 2 and the off-axis measuring instrument 12.

[0044] In S13, the control section 11 determines whether the alignment target substrate 8 is the first substrate of a lot. The lot is a unit of processing the substrate 8 (manufacturing unit). The substrates of the same lot are stored in the same environment in the manufacturing site, and tend to have the same characteristics. Thus, in the present embodiment, the same baseline correction amount is used for the substrates of the same lot to correct the baseline to perform exposure. In the case where the substrate 8 is the first substrate of the lot, the processing proceeds to S14, and in the case where the substrate 8 is not the first substrate of the lot, the processing proceeds to S17.

[0045] In S14, the control section 11 causes the alignment measuring instrument 2 and the off-axis measuring instrument 12 to perform high-speed measurement, and acquires a baseline measurement value. Specifically, a few times (a second number of times which is less than a first number of times) of detection of the alignment mark by the alignment measuring instrument 2 and the off-axis measuring instrument 12, for example, one time, are performed, and detection results thereof are acquired. Further, the baseline measurement value is calculated from the detection results of one time by the alignment measuring instrument 2 and the off-axis measuring instrument 12. Here, the baseline measurement value acquired in the nth (n is an integer of one or more) batch is expressed as a baseline measurement value M n (the baseline M n ).

[0046] In the present embodiment, the number of times of detection of the alignment mark in the high-speed measurement (S14) is one, but the purpose of the high-speed measurement is to measure faster than the high-precision measurement (S12). Therefore, the number of times of detection of the alignment mark in the high-speed measurement (the second number of times) can be a number of times which is less than the number of times of detection of the alignment mark in the high-precision measurement (the first number of times). For example, the number of times of detection of the alignment mark in the high-speed measurement can also be one or more times, a plurality of times. Further, in the case where the number of times of detection of the alignment mark in the high-speed measurement is a plurality of times, the average value obtained by averaging the detection results of the plurality of times, or the statistical value obtained by statistically processing the detection results of the plurality of times can also be used as the baseline measurement value M base . n .

[0047] In S15, the control section 11 compares the baseline reference value M base acquired in S12 and the baseline measurement value M n acquired in S14, and determines whether or not the difference therebetween exceeds an allowable range in accordance with the following expression (1). Further, in expression (1), Tol represents the allowable range (an amount of detection error which can be tolerated) of the difference M base between the baseline reference value M n and the baseline measurement value M base . n .

[0048]

[0049] In the following sequence, the baseline reference value M base is used to calculate (determine) a baseline correction amount. In the case where the difference between the baseline reference value M base and the baseline measurement value M n exceeds the allowable range, it is considered that the actual baseline greatly deviates from the baseline reference value M base . Therefore, after the baseline is changed, the baseline reference value M baseThe exposure accuracy including the overlay accuracy and the like is reduced when the calculated baseline correction amount is corrected. Therefore, in a case where the difference between the baseline reference value M base and the baseline measurement value M n exceeds the allowable range, that is, in a case where the difference is large, the baseline reference value after the baseline variation needs to be found.

[0050] In S16, the control section 11 causes the alignment measuring instrument 2 and the off-axis measuring instrument 12 to perform high-accuracy measurement, and the baseline reference value M base is newly found. Specifically, as in S12, the detection of the alignment mark by the alignment measuring instrument 2 and the detection of the alignment mark by the off-axis measuring instrument 12 are performed a plurality of times (1st time), for example, 16 times, and the respective detection results are found. Further, the new baseline reference value M base is found from the new 16-time detection results by the alignment measuring instrument 2 and the off-axis measuring instrument 12. In this way, by updating the baseline reference value M base , the baseline after the variation can be dealt with. In addition, the high-accuracy measurement in S16 is performed for the nth batch, so the baseline measurement value M n is also updated with the same value as the baseline reference value M base .

[0051] In S17, the control section 11 decides (calculates) the baseline correction amount used in the nth batch from the baseline reference value M base and the baseline measurement value M n . The baseline reference value M base is a value measured with high accuracy, so it is preferable in terms of reliability. The baseline measurement value M n is a value measured in the current batch, so it is preferable in terms of adaptability. Therefore, by combining the baseline reference value M base and the baseline measurement value M n , the baseline correction amount closer to the true value than ever before can be decided.

[0052] Further, the baseline reference value M base used when the baseline correction amount is decided is the baseline reference value M base found in S12 if not via S16, or the baseline reference value M base re-found (updated) in S16 if via S16. Similarly, the baseline measurement value M n used when the baseline correction amount is decided is the baseline measurement value M n found in S14 if not via S16, or the same value as the baseline reference value M base updated in S16 if via S16.

[0053] Here, one example of a specific method for determining the baseline correction amount in S17 will be described. In the present embodiment, the baseline correction amount X base is determined by weighting the baseline reference value M n and the baseline measurement value M i respectively. For example, when the weight given to the baseline measurement value M n is set to a weight W, the baseline reference value M base is given a weight (1-W). Thus, when the relationship of the baseline correction amount X i , the baseline measurement value M n , and the baseline reference value M base is formulated, it is expressed by the following equation (2).

[0054]

[0055] In equation (2), i represents the elapsed time from the start of measurement and can be converted to the batch number n, which represents the periodic measurement. M i represents the baseline measurement value obtained by the high-speed measurement at i hours, X i represents the baseline correction amount at i hours, and W represents the weight (weighting ratio) given to the baseline measurement value obtained by the high-speed measurement.

[0056] Referring to equation (2), the baseline measurement value M i and the baseline reference value M base are actually measured values, and the baseline correction amount X i is determined by weighting (multiplying) them by W and (1-W) respectively. In addition, the baseline measurement value M i is a measurement value obtained by performing high-speed measurement, i.e., under low-precision conditions, and thus includes a deviation. In other words, the baseline measurement value M i is a value that reflects the measurement reproducibility of each of the alignment measurement instrument 2 and the off-axis measurement instrument 12. Thus, as shown in equation (2), the baseline correction amount X i including the baseline measurement value M i is also dispersed.

[0057] In the following equation (3), the fluctuation of the baseline caused by continuous exposure in the exposure apparatus 100 is shown.

[0058]

[0059] In equation (3), i represents the elapsed time from the start of measurement, M true (i) represents the baseline (actual value), A(i) represents the amount of change in the baseline over time, and M base0The initial measurement value indicating the baseline. Equation (3) is an equation that roughly indicates the baseline (variation), and is formulated by statistical processing from values obtained in experiments.

[0060] Here, the baseline correction amount X i is for correcting the baseline M true (i) indicated by equation (3). Therefore, the difference between the baseline correction amount X i and the baseline M true (i) is preferably small. The standard deviation S of the baseline correction amount X i is indicated by equation (4) below.

[0061]

[0062] Referring to equation (4), when the standard deviation S is sufficiently small, the distribution of the baseline correction amount X i is close to the baseline M true (i) indicated by equation (3), indicating correctness. Also, as indicated by equation (2), the baseline correction amount X i is determined by the weight W, so when the standard deviation S is sufficiently small, it indicates that the weight W is also correct.

[0063] Therefore, in the present embodiment, the weight W is calculated in accordance with equation (5) below. Equation (5) is obtained by substituting equation (2) and equation (3) into equation (4).

[0064]

[0065] The weight W is substituted in the range of 0 to 1 in such a way that the standard deviation S indicated by equation (5) becomes the smallest. It is considered that the weight W at which the standard deviation S becomes the smallest is closest to the true value, so the weight W at which the standard deviation S becomes the smallest is adopted as the weight given to the baseline measurement value M n . Referring to equation (5), the baseline measurement value M i is a value that reflects the measurement reproducibility of each of the alignment measuring instrument 2 and the off-axis measuring instrument 12, and the baseline variation amount A(i) is a value that reflects the temporal variation of the baseline. In this way, the weight W is calculated (determined) in accordance with the reliability of the detection results obtained by each of the alignment measuring instrument 2 and the off-axis measuring instrument 12, in detail, in accordance with the measurement reproducibility of each measuring instrument and the temporal variation of the baseline.

[0066] Also, the weight W is temporarily changed (increased or decreased) in accordance with the number of times (the first number and the second number) that the alignment marks are detected by the alignment measuring instrument 2 and the off-axis measuring instrument 12, so it is possible to reflect the reliability of each alignment measurement value.

[0067] <Second Embodiment>

[0068] Figure 3This is a flowchart illustrating the method for determining the baseline correction amount in the second embodiment. The determination method is executed by the control unit 11, which controls all parts of the exposure apparatus 100 overall. Thus, in this embodiment, the control unit 11 functions as a processing unit that performs the process of determining the baseline correction amount.

[0069] In this embodiment, such as Figure 3 As shown, instead of S17 in the first embodiment, i.e., determining the baseline correction amount according to formula (2), S21 is set.

[0070] In S21, the control unit 11 determines the baseline measurement value M obtained in the nth batch (n is an integer greater than or equal to 2) based on the baseline measurement value M. n The baseline correction amount X for the (n-1)th batch n-1 Determine the baseline correction amount X to be used in the nth batch. n Thus, in this embodiment, the baseline measurement value M obtained by performing high-speed measurement using the alignment measuring instrument 2 and the off-axis measuring instrument 12 is used as the basis for the measurement. n And the baseline correction amount X from the previous batch n-1 Determine the baseline correction amount X for this batch. n In addition, the baseline correction amount X n-1 Based on the baseline reference value M obtained in S12 base And the baseline measurements M1~M1 obtained in S14 up to the (n-1)th batch. n-1 (baseline M1~M) n-1 )Decide.

[0071] Here, an example of the specific method used to determine the baseline correction amount in S21 is described. Regarding the first batch, since there is no baseline correction amount for the previous batch, the baseline correction amount X1 is determined according to the following formula (6), similar to the first embodiment.

[0072]

[0073] For the second batch, the baseline correction amount X1 is used, and the baseline correction amount X2 is determined according to the following formula (7).

[0074]

[0075] When generalizing equation (7), the baseline correction amount X used in the nth batch is... n It can be represented by the following formula (8).

[0076]

[0077] Thus, in this embodiment, by combining the (n-1)th baseline correction amount Xn-1 and the baseline measurement value M n determining the baseline correction amount X n At this time, as in the first embodiment, the baseline correction amount X n-1 and the baseline measurement value M n are respectively weighted. Specifically, when the weight to be given to the baseline measurement value M n is set to a weight W, the baseline correction amount X n-1 may be weighted by (1-W). Further, as for the calculation of the weight W, it is the same as in the first embodiment, so detailed description thereof is omitted here.

[0078] Comparing equation (8) and equation (2), in equation (8), information about the baseline measurement value obtained in the high-speed measurement performed in the previous batch is included. Therefore, in equation (8), it is possible to include information about the change of the baseline measurement value M n-1 to the baseline measurement value M n over time to determine the baseline correction amount X n . Further, the total number of samples of the baseline measurement values used when determining the baseline correction amount X n is increased, so it is possible to suppress the influence on the measurement reproducibility of each of the alignment measuring instrument 2 and the off-axis measuring instrument 12.

[0079] Further, in the present embodiment, in the case where the difference between the baseline reference value M base and the baseline measurement value M n exceeds the allowable range, high-precision measurement is also performed, and the baseline reference value M base and the baseline measurement value M n are again obtained (S16). The baseline measurement value M n obtained again is more preferable in terms of reliability and reproducibility than the baseline measurement value M n obtained in the high-speed measurement.

[0080] Other Embodiments

[0081] Embodiments of the present application can also be realized by a computer of a system or an apparatus reading a program of software (program) for executing the functions of the above-described embodiments and a central processing unit (CPU) or a micro processing unit (MPU) of the computer or the apparatus executing the program through a network or various storage media.

[0082] The manufacturing method of the article in the present embodiment is suitable for manufacturing, for example, an article such as a flat panel display, a liquid crystal display element, a semiconductor element, a MEMS, and the like. The manufacturing method includes a process of exposing a substrate on which a photosensitive agent is applied using the exposure apparatus 100 (exposure process) described above, and a process of developing the exposed photosensitive agent. Further, using the pattern of the developed photosensitive agent as a mask, a circuit pattern is formed on the substrate by performing a process such as etching, an ion implantation process, and the like on the substrate. These processes of exposure, development, etching, and the like are repeated to form a circuit pattern composed of a plurality of layers on the substrate. In a subsequent process, the substrate on which the circuit pattern is formed is cut (processed), and a chip mounting, bonding, and inspection process is performed. Further, the manufacturing method can include other known processes (oxidation, film formation, evaporation, doping, planarization, resist peeling, and the like). The manufacturing method of the article in the present embodiment is more advantageous than conventional ones in at least one of performance, quality, productivity, and production cost of the article.

[0083] The present disclosure is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the spirit and scope of the present disclosure. Therefore, a claim is appended in order to disclose the scope of the present disclosure.

Claims

1. A decision method of deciding a baseline correction amount of a baseline indicating a distance between an optical axis of a first measuring instrument and an optical axis of a second measuring instrument, the first measuring instrument detecting a mark via a projection optical system that projects light from a master onto a substrate, the second measuring instrument detecting a mark without via the projection optical system, the decision method characterized by having: a first step of obtaining a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument; and a second step of deciding the baseline correction amount based on a difference between the reference baseline and a baseline obtained from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument.

2. The decision method according to claim 1, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a third number of times of use of the first measuring instrument and the second measuring instrument. In the second step, the baseline M is obtained from the detection results of the second number of measurements, which is less than the first number of measurements, using the first measuring instrument and the second measuring instrument, with respect to the nth batch n n is an integer of 1 or more; and Step 3: determining the baseline correction amount X used in the nth batch based on the reference baseline obtained in Step 1 and the baseline M obtained in Step 2 n n .​ 3. The decision method according to claim 2, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a fourth number of times of use of the first measuring instrument and the second measuring instrument. In the third process, a baseline correction amount X used in the nth batch is determined by combining the reference baseline obtained in the first process and the baseline M obtained in the second process n . n .

4. The decision method according to claim 3, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a fifth number of times of use of the first measuring instrument and the second measuring instrument. In the third process, the reference baseline obtained in the first process and the baseline M obtained in the second process are compared to determine the baseline correction amount X used in the nth batch n The weight is assigned to determine the baseline correction amount X used in the nth batch n .

5. The decision method according to claim 3, characterized in that, in the second step, the weight is decided based on a reliability of a detection result obtained by each of the first measuring instrument and the second measuring instrument. In the third process, the reference baseline obtained in the first process is weighted (1-W), and the baseline M obtained in the second process is weighted (W), to determine the baseline correction amount X of the nth batch n The weighting W is determined to decide the baseline correction amount X of the nth batch n .

6. The decision method according to claim 3, characterized in that, in the second step, the weight is decided based on a measurement reproducibility of the first measuring instrument, a measurement reproducibility of the second measuring instrument, and a temporal change of the baseline.

7. The decision method according to claim 3, characterized in that, in the second step, the weight is changed based on the first number of times and the second number of times.

8. The decision method according to claim 3, characterized by further having: a third step of deciding the baseline correction amount based on a difference between the reference baseline and a baseline obtained from a detection result of a sixth number of times of use of the first measuring instrument and the second measuring instrument; and a fourth step of deciding the baseline correction amount based on a difference between the reference baseline and a baseline obtained from a detection result of a seventh number of times of use of the first measuring instrument and the second measuring instrument.

9. The decision method according to claim 1, characterized in that, in the first step, the first number of times includes a plurality of times.

10. The decision method according to claim 9, characterized in that, in the first step, the reference baseline is obtained based on an average value or a statistical value of detection results of the first number of times.

11. The decision method according to claim 1, characterized in that, in the second step, the second number of times includes one or more times.

8. The decision method of claim 1, wherein, 12. The decision method according to claim 1, characterized in that, in the second step, the second number of times includes a plurality of times. Step 4: Determine the reference baseline obtained in step 1 and the baseline M obtained in step 2. n Does the difference exceed the allowable range? 13. The decision method according to claim 12, characterized in that, in the second step, the weight is decided based on a reliability of a detection result obtained by each of the first measuring instrument and the second measuring instrument.

14. The decision method according to claim 1, characterized by having: a first step of obtaining a reference baseline from a detection result of a first number of times of use of the first measuring instrument and the second measuring instrument; and a second step of deciding a baseline correction amount based on a difference between the reference baseline and a baseline obtained from a detection result of a second number of times of use of the first measuring instrument and the second measuring instrument.

15. The decision method according to claim 14, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a third number of times of use of the first measuring instrument and the second measuring instrument.

16. The decision method according to claim 15, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a fourth number of times of use of the first measuring instrument and the second measuring instrument.

17. The decision method according to claim 16, characterized in that, in the second step, the baseline correction amount is decided based on a difference between the reference baseline and a baseline obtained from a detection result of a fifth number of times of use of the first measuring instrument and the second measuring instrument.

18. An information processing apparatus characterized by ​ ​ ​ ​ ​ In the second process, the baseline M is found from the average or statistical value of the detection results of the second number of times n . ​ ​ In the second step, the baseline M is obtained from the detection results of the second number of measurements, which is less than the first number of measurements, using the first measuring instrument and the second measuring instrument, with respect to the nth batch n n is an integer of 2 or more; and Step 3: The baseline correction amount X used in the nth batch is determined based on the reference baseline obtained in the first step and the baselines M1 to M n-1 obtained from the detection results of the second number of measurements using the first and second measuring instruments n Step 4: The baseline correction amount X used in the nth batch is determined based on the baseline correction amount X of the (n-1)th batch n Step 5: The baseline correction amount X used in the nth batch is determined based on the baseline correction amount X of the (n-1)th batch n-1 Step 6: The baseline correction amount X used in the nth batch is determined based on the reference baseline obtained in the first step and the baselines M1 to M n-1 obtained from the detection results of the second number of measurements using the first and second measuring instruments ​ In the third process, a baseline correction amount X n-1 , and the baseline M n , obtained in the second process, are combined to determine a baseline correction amount X n to be used in the nth batch. ​ In the third process, the baseline correction amount X n-1 and the baseline M n obtained in the second process are respectively weighted to determine the baseline correction amount X n to be used in the nth batch. ​ In the third process, the baseline correction amount X n-1 weighting (1-W) is given to the baseline M n weighting W is given to the baseline correction amount X n . ​ The device includes a processing unit that determines a baseline correction amount for a baseline representing the distance between the optical axes of a first measuring instrument and a second measuring instrument. The first measuring instrument detects a mark via a projection optics system that projects light from the original onto the substrate, while the second measuring instrument detects the mark without using the projection optics system. The processing unit A baseline is obtained from the detection results of the first number of times using the first measuring instrument and the second measuring instrument. Regarding the n-th batch, a baseline M is obtained from detection results of a smaller number of times than the first number of times using the first measuring instrument and the second measuring instrument n , n is an integer of 1 or more, According to the reference baseline and the baseline M n , a baseline correction amount X used in the nth batch is determined n .

19. An information processing device, characterized in that, The device includes a processing unit that determines a baseline correction amount for a baseline representing the distance between the optical axes of a first measuring instrument and a second measuring instrument. The first measuring instrument detects a mark via a projection optics system that projects light from the original onto the substrate, while the second measuring instrument detects the mark without using the projection optics system. The processing unit A baseline is obtained from the detection results of the first number of times using the first measuring instrument and the second measuring instrument. Regarding the n-th batch, a baseline M is obtained from detection results of a smaller number of times than the first number of times using the first measuring instrument and the second measuring instrument n , n is an integer of 2 or more, Based on the baseline correction amount X of the (n-1)th batch n-1 and the baseline M n Determine the baseline correction amount X to be used in the nth batch. n The baseline correction amount X of the (n-1)th batch n-1 It is based on the aforementioned baseline and the baselines M1~M1 for each batch up to the (n-1)th batch, determined from the detection results of the second number of tests using the first measuring instrument and the second measuring instrument. n-1 It was decided.

20. An exposure apparatus which exposes a substrate with a master, characterized by comprising: have: A projection optics system projects light from the original onto the substrate; The first measuring instrument detects the mark via the projection optical system; The second measuring instrument detects the mark without using the projection optical system; as well as The processing unit performs a baseline correction calculation to determine the baseline representing the distance between the optical axes of the first and second measuring instruments. The processing unit A baseline is obtained from the detection results of the first number of times using the first measuring instrument and the second measuring instrument. Regarding the n-th batch, a baseline M is obtained from detection results of a smaller number of times than the first number of times using the first measuring instrument and the second measuring instrument n , n is an integer of 1 or more, According to the reference baseline and the baseline M n , a baseline correction amount X used in the nth batch is determined n .

21. An exposure apparatus which exposes a substrate with a master, characterized by comprising: have: A projection optics system projects light from the original onto the substrate; The first measuring instrument detects the mark via the projection optical system; The second measuring instrument detects the mark without using the projection optical system; as well as The processing unit performs a baseline correction calculation to determine the baseline representing the distance between the optical axes of the first and second measuring instruments. The processing unit A baseline is obtained from the detection results of the first number of times using the first measuring instrument and the second measuring instrument. Regarding the n-th batch, a baseline M is obtained from detection results of a smaller number of times than the first number of times using the first measuring instrument and the second measuring instrument n , n is an integer of 2 or more, Based on the baseline correction amount X of the (n-1)th batch n-1 and the baseline M n Determine the baseline correction amount X to be used in the nth batch. n The baseline correction amount X of the (n-1)th batch n-1 It is based on the aforementioned baseline and the baselines M1~M1 for each batch up to the (n-1)th batch, determined from the detection results of the second number of tests using the first measuring instrument and the second measuring instrument. n-1 It was decided.

22. An exposure method of exposing a substrate with a master, characterized by, have: The process of determining the baseline correction amount of the baseline representing the distance between the optical axis of the first measuring instrument and the optical axis of the second measuring instrument, wherein the first measuring instrument detects the mark via a projection optics system that projects light from the original onto the substrate, and the second measuring instrument detects the mark without using the projection optics system; as well as The process of exposing the substrate by correcting for variations in the baseline using the baseline correction amount determined in the aforementioned process. The decision-making process includes: The first step involves obtaining a baseline from the detection results of the first number of times using the first measuring instrument and the second measuring instrument; In the second step, the baseline M is obtained from the detection results of the second number of measurements, which is less than the first number of measurements, using the first measuring instrument and the second measuring instrument, with respect to the nth batch n n is an integer of 1 or more; and Step 3: determining the baseline correction amount X used in the nth batch based on the reference baseline obtained in Step 1 and the baseline M obtained in Step 2 n n .​ 23. An exposure method of exposing a substrate with a master, characterized by, have: The process of determining the baseline correction amount of the baseline representing the distance between the optical axis of the first measuring instrument and the optical axis of the second measuring instrument, wherein the first measuring instrument detects the mark via a projection optics system that projects light from the original onto the substrate, and the second measuring instrument detects the mark without using the projection optics system; as well as The process of exposing the substrate by correcting for variations in the baseline using the baseline correction amount determined in the aforementioned process. The procedure of the decision includes: In a first procedure, a reference baseline is obtained from detection results of a first number of measurements using the first measuring instrument and the second measuring instrument; In the second step, the baseline M is obtained from the detection results of the second number of measurements, which is less than the first number of measurements, using the first measuring instrument and the second measuring instrument, with respect to the nth batch n n is an integer of 2 or more; and Step 3: The baseline correction amount X used in the nth batch is determined based on the reference baseline obtained in the first step and the baselines M1 to M n-1 obtained from the detection results of the second number of measurements using the first and second measuring instruments n Step 4: The baseline correction amount X used in the nth batch is determined based on the reference baseline obtained in the first step and the baselines M1 to M n obtained from the detection results of the second number of measurements using the first and second measuring instruments n-1 Step 5: The baseline correction amount X used in the nth batch is determined based on the reference baseline obtained in the first step and the baselines M1 to M n-1 obtained from the detection results of the second number of measurements using the first and second measuring instruments 24. A method of manufacturing an article, characterized by, Having: A procedure of exposing a substrate using the exposure apparatus according to claim 20; A procedure of developing the substrate after exposure; and A procedure of manufacturing an article from the substrate after development.

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