KR102649936B1 - Determination method, exposure method, exposure apparatus and method of manufacturing article - Google Patents

Abstract

[Project] Provide a connected exposure technology that is advantageous for both the stacking precision of upper and lower layers and the connection precision of adjacent shots.
[Solution] A first image is formed by exposing a first shot area of the substrate, a second image is formed by exposing a second shot area overlapping a part of the first shot area, and the first shot area is exposed to form a second image. A determination method for determining a correction amount regarding alignment of the first shot area and the second shot area for connection exposure to obtain an image in which the image and the second image are connected to each other, wherein superimposing upper and lower layers is performed. A first position misalignment amount, which is the amount of position misalignment between the overlapping marks, is obtained, and a second position misalignment amount is obtained, which is the amount of position misalignment between the connection position measurement marks for aligning the first shot area with the second shot area. , the positional deviation amount obtained by adding a predetermined ratio of the second positional deviation amount to the first positional deviation amount is the first positional deviation amount in the connection area where the first shot area and the second shot area overlap. It is determined as the correction amount of the image, and the positional deviation amount obtained by subtracting the remaining ratio to the predetermined ratio of the second positional deviation amount from the first positional deviation amount is defined as the correction amount of the second image in the connection area. It is decided as

Description

Determination method, exposure method, exposure apparatus, and article manufacturing method {DETERMINATION METHOD, EXPOSURE METHOD, EXPOSURE APPARATUS AND METHOD OF MANUFACTURING ARTICLE}

The present invention relates to a crystal method, an exposure method, an exposure apparatus, and an article manufacturing method.

Semiconductors, liquid crystal panels, etc. are manufactured through the photolithography process. In the photolithography process, a scanning exposure device is used to project a pattern of an original plate (mask) onto a substrate (glass substrate or wafer) coated with a photoresist through a projection optical system while scanning the exposure area. In recent years, the size of displays such as liquid crystal panels has progressed, and it has become necessary to expose glass substrates that exceed, for example, 2 m square. In order to cope with the large size of such a substrate, the entire exposed area on the substrate is not exposed at once, but the exposed area on the substrate is divided into several shot areas and exposed. At this time, connection exposure is performed to expose parts of adjacent shot areas by overlapping them.

In connection exposure, if the overlay error in the area (connection area) where adjacent shot areas are overlapped becomes large, unevenness occurs in the connection area. Patent Document 1 specializes in either the amount of positional misalignment between the upper and lower layers in the connection area or the amount of positional misalignment between adjacent shots, obtains a correction amount to reduce the amount of misalignment, and exposes using the correction amount. The technology is starting. Additionally, Patent Document 2 discloses a technique for correcting the shot position by using a plurality of shots constituting one device as one unit. Correction of the shot position is performed so that the difference in overlap accuracy at the connecting portion of the plurality of shots constituting one device is minimized.

Patent Document 1: Japanese Patent Laid-open Publication No. 07-321026 Patent Document 2: Japanese Patent Laid-open Publication No. 09-306818

When performing connected exposure, the positional misalignment between adjacent shots is the most important indicator that determines the performance of the device being manufactured. Nevertheless, in the conventional correction, only the amount of positional discrepancy between the upper and lower layers is corrected and the positional discrepancy between adjacent shots is not considered, or only the amount of positional discrepancy between adjacent shots is corrected and the positional discrepancy between the upper and lower layers is not considered. . In response to this, a method of preferentially correcting the positional discrepancy between adjacent shots (connection priority correction) has also been proposed. According to that method, the correction effect for the positional misalignment between the upper and lower layers was reduced, but the required precision of the connected exposure so far was satisfied.

However, as substrates become larger and patterns become finer, there is an increasing demand to ensure high precision in both the stacking accuracy of the upper and lower layers and the connection accuracy of adjacent shots. In other words, there is a need for a method to correct both the misalignment of the upper and lower layers and the positional misalignment between adjacent shots with high precision.

The purpose of the present invention is to provide a technology for connected exposure that is advantageous for both the accuracy of overlapping of upper and lower layers and the accuracy of connection of adjacent shots.

According to one aspect of the present invention, a first shot area of the substrate is exposed to form a first image, and a second shot area overlapping a part of the first shot area is exposed to form a second image, A determination method for determining a correction amount regarding alignment of the first shot area and the second shot area for connection exposure to obtain an image in which the first image and the second image are connected to each other, wherein the first image is By exposing the shot area, a first mark is applied to a connection area where the first shot area and the second shot area overlap, for alignment with a base mark formed on a lower layer of the connection area, and the first mark A second mark is formed to align the shot area with the second shot area, the second shot area is exposed, and a third mark is formed to overlap the first mark for alignment with the ground mark. In addition, a fourth mark is formed at a position overlapping with the second mark in the connection area, and the position of the composite mark formed by overlapping the first mark and the third mark with respect to the base mark The amount of misalignment is determined as the first position misalignment amount, the amount of positional misalignment of the fourth mark with respect to the second mark is determined as the amount of second position misalignment, and the amount of misalignment of the second position is calculated by dividing the first amount of misalignment by a predetermined amount. The positional deviation amount obtained by adding the ratio is determined as a correction amount of the first image in the connection area where the first shot area and the second shot area overlap, and the second position is calculated from the first positional deviation amount. The amount of positional misalignment obtained by subtracting the remaining ratio from the predetermined ratio of the amount of misalignment is determined as a correction amount of the second image in the connection area, and the base mark, the first mark, and the second mark are determined as a correction amount for the second image in the connection area. , the third mark, and the fourth mark are each formed in the connection area at a position that does not include both ends of the direction of the overlap width of the first shot area and the second shot area, and the predetermined The ratio is the base mark, the first mark, the second mark, the third mark, and the third mark in the direction of the overlap width between the first shot area and the second shot area in the connection area. A determination method is provided, characterized in that the ratio is based on the position of the 4 marks.

According to the present invention, it is possible to provide a connected exposure technology that is advantageous for both the accuracy of overlapping of upper and lower layers and the accuracy of connection of adjacent shots.

[Figure 1] A diagram showing the configuration of an exposure apparatus in an embodiment.
[Figure 2] A diagram showing an example of illuminance distribution during connected exposure.
[Figure 3] Flowchart of the process for determining the correction amount and the exposure process.
[Figure 4] A diagram showing an example of mark arrangement of Shot S1.
[Figure 5] A diagram showing an example of mark arrangement of Shot S2.
[FIG. 6] A diagram showing an example of a superimposed mark and a connection position measurement mark in a connection area.
[Figure 7] A diagram showing an example of a connection position measurement mark.
[Figure 8] A diagram showing an example of a virtual mark set in a connection area.
[Figure 9] A diagram showing an example of a virtual mark set in a connection area.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First embodiment>

Figure 1 shows a schematic configuration of an exposure apparatus in an embodiment. This exposure apparatus is, for example, a scanning exposure apparatus employing a mirror projection method using a projection optical system. At this time, in this specification and drawings, the direction is indicated in the XYZ coordinate system where the direction parallel to the substrate holding surface by the substrate stage is the XY plane. The directions parallel to the X, Y, and Z axes in the XYZ coordinate system are called the X, Y, and Z directions, respectively. Additionally, the scanning direction of the original plate and substrate during exposure is set to the Y direction.

The exposure apparatus includes an original stage 31 on which an original plate 30 (mask) is mounted, a substrate stage 61 on which a substrate 60 (for example, a glass plate) is mounted, and an illumination device that illuminates the original plate 30. It includes an optical system 10 and a projection optical system 40 that projects the pattern of the original plate 30 onto the substrate 60. The original plate 30 and the substrate 60 are disposed at substantially optically conjugate positions (object plane and image plane of the projection optical system 40) through the projection optical system 40. A slit imaging system 20 that shapes the exposure light is disposed between the illumination optical system 10 and the original stage 31. In addition, when scanning and exposing the substrate 60, an 40) and the substrate stage 61. The control unit 70 controls the driving of each part of the exposure apparatus.

The illumination optical system 10 may include a light source such as an ultra-high pressure mercury lamp, a wavelength selection filter, a lens group, a shutter, etc. The illumination optical system 10 irradiates light of a wavelength suitable for exposure toward the slit imaging system 20. The slit imaging system 20 has a slit (not shown), and has an exposure width that satisfies the required exposure amount for incident light from the illumination optical system 10 at a constant stage scanning speed (for example, the upper limit of the scanning speed, etc.). Formulated as

The disc stage 31 on which the disc 30 is mounted is scanned in the Y direction by a drive mechanism (not shown) under control by the control unit 70. A plurality of reflectors 32 are arranged on the disk stage 31. The plurality of reflectors 32 each reflect measurement light from the interferometer 33 disposed outside the disk stage 31. The interferometer 33 receives the reflected measurement light and constantly monitors and measures the position of the disk stage 31. The control unit 70 controls the position and speed of the disk stage 31 based on the results of measurement by the interferometer 33.

The projection optical system 40 has a mirror and a lens, and projects the pattern formed on the original plate 30 onto the substrate 60 by reflecting and refracting the exposure light. Additionally, the mirror and lens are driven in the X, Y, and Z directions by a drive mechanism (not shown) under control by the control unit 70 to generate arbitrary magnification and shift.

In the exposure apparatus of this embodiment, a first shot area of the substrate is exposed to form a first image, and a second shot area overlapping a part of the first shot area is exposed to form a second image. , connection exposure is performed to obtain an image in which the first image and the second image are connected to each other. The exposure apparatus is provided with an X light-shielding plate 50 to perform this connected exposure. In addition, in the following description, the “short area” is also simply referred to as “short.” The By moving the The exposure amount is controlled. Accordingly, it becomes possible to control the connected exposure for the connected shot layout shown in FIG. 2A. In other words, as shown in Figure 2b, the illuminance distribution in the non-connected area, which is an area other than the connected area in shot S1 (first shot area), is set to 100%, and the illuminance distribution at each X position in the connected area is negative. Let's tilt it. For example, the exposure amount (illuminance) is attenuated linearly from 100% to 0% from one end to the other end of the X-direction of the connection area. Additionally, as shown in FIG. 2C, the illuminance distribution in the non-connected area of shot S2 (second shot area) is set to 100%, and the illuminance distribution at each X position in the connected area is set to a positive slope. For example, the exposure amount is linearly increased from 0% to 100% from one end to the other end of the X-direction of the connection area. In this way, when exposing shot S1 and when exposing shot S2, the exposure amount in the connected area is crossfaded. Accordingly, as shown in FIG. 2D, the integrated illuminance distribution for the connected area and the non-connected area is equalized to 100%.

The substrate stage 61 on which the substrate 60 is mounted is scanned in the X, Y, and Z directions by a drive mechanism (not shown) under control by the control unit 70. A plurality of reflectors 62 are disposed on the substrate stage 61. The plurality of reflectors 62 each reflect measurement light from the interferometer 63 disposed outside the substrate stage 61. The interferometer 63 receives the reflected measurement light and constantly monitors and measures the position of the substrate stage 61. The control unit 70 controls the position and speed of the substrate stage 61 based on the results of measurement by the interferometer 63.

The alignment scope 80 detects the alignment mark of the substrate 60 through the original plate 30 and the projection optical system 40. On the other hand, the off-axis scope 81 is disposed below the projection optical system 40 and detects the alignment mark of the substrate 60 without passing through the original plate 30 and the projection optical system 40.

The control unit 70 functions as a processing unit that performs processing to determine a correction amount related to the alignment of shots S1 and shot S2, and also functions as a control unit that controls joint exposure. The control unit 70 may include a data holding unit 71, a drive amount calculation unit 72, and a drive instruction unit 73 as its functional configuration. The data storage unit 71 stores drive parameters such as It holds various acquired measurement data. The drive amount calculation unit 72 calculates various correction components such as position offset, rotation, and magnification in the X, Y, and Z directions from the data held in the data holding unit 71 using general statistical methods. Additionally, the drive amount calculation unit 72 determines the drive instruction amount for each axis based on the drive parameters and the calculated correction component. The drive instruction unit 73 uses the drive instruction amount for each drive mechanism determined by the drive amount calculation unit 72 to output a drive instruction for each drive mechanism. Additionally, the control unit 70 may be configured by, for example, a computer device including a CPU (central processing unit) and memory as its hardware configuration. In this case, the data holding unit 71 can be realized by memory, and the drive amount calculation unit 72 and drive instruction unit 73 can be realized by CPU.

(Example 1)

Referring to the flowchart in FIG. 3, the outline of the process for determining the correction amount for the alignment of shots S1 and shot S2 for connected exposure and the exposure process performed based on the determined correction amount in the present embodiment will be described. First, the first connected exposure is performed on shot S1 and shot S2 (S101). This first connected exposure is an exposure for determining the correction amount. The substrate used at this time may be a production substrate or a test substrate. Next, the overlay error of the upper and lower layers and the positional misalignment of shots S1 and shot S2 (alignment misalignment of left and right shots) in the connection area are measured (S102). This measurement may be performed using a measuring device external to the exposure apparatus, or may be performed using an alignment scope 80 or an off-axis scope 81.

The control unit 70 calculates (determines) the correction amount based on this measurement result (S103). The calculated correction amount is stored, for example, in the data storage unit 71 as a correction parameter during exposure. Correction parameters include shift, rotation, and magnification of the shot area, and control objects of the exposure device include control data of the stage and optical system, and the calculated correction amounts can be converted into correction values appropriate for these parameters.

After that, a second exposure (next connection exposure) is performed. The second exposure referred to here may be the main exposure using a production substrate (S104). Here, the control unit 70 performs connected exposure by reflecting the correction value.

Hereinafter, the determination method for determining the correction amount for the alignment of shot S1 and shot S2 according to S101 to S103 described above will be described in detail. Figure 4 is a schematic diagram of shot S1 exposed in S101. In this embodiment, measurement for overlapping the upper and lower layers and measurement for alignment of shot S1 and shot S2 are performed using, for example, box-in-box marks. In Fig. 4, an out-box mark 91 (base mark) constituting a superimposed mark has already been formed in the layer below the connection area. When exposing shot S1, an in-box mark 90 (first mark) is formed for alignment with the out-box mark 91. Additionally, during exposure of shot S1, an out-of-box mark 92 (second mark), which is a connection position measurement mark for position alignment between shots S1 and shot S2, is also formed in the connection area.

As described above, in Shot S1, the exposure amount (illuminance) is linearly attenuated from 100% to 0% from one end to the other end of the X-direction of the connection area. As shown in Figure 4, each mark formed in the connection area is arranged at a predetermined position x1 in the direction of the overlap width of shot S1 and shot S2 (X direction), and the exposure amount at position x1 is Let the attenuation rate be a%. An overlay error (overlay error) is detected from the difference in position between the out-box mark 91 formed in the lower layer and the in-box mark 90 formed in the upper layer. However, at the time the shot S1 is exposed, the illuminance at the position x1 is only (100-a)%, so the in-box mark 90 and the out-box mark 92 are not completely formed.

Figure 5 is a schematic diagram of shot S2 exposed in S101. During exposure of Shot S2, an in-box mark 93 (third mark) is formed to overlap the in-box mark 90 for alignment with the out-box mark 91, which is an underlying mark. Additionally, during exposure of shot S2, an in-box mark 94 (fourth mark), which is a connection position measurement mark for position alignment between shot S1 and shot S2, is also formed at a position overlapping with the out-box mark 92. A nesting error can be detected from the difference in position between the out-box mark 91 formed in the lower layer and the in-box mark 93 formed in the upper layer. However, since the illuminance at the position It is fully formed here. In this way, the inbox mark 90 and the inbox mark 93 are overlapped to form a composite inbox mark 95 (composite mark), as shown in Fig. 6. Therefore, the measured positional deviation amount of the synthetic inbox mark 95 with respect to the outbox mark 91 is the first positional deviation amount, which is the positional deviation amount between the overlapping marks 91 and 95 for overlapping the upper and lower layers. It is saved as

Likewise, the inbox mark 94 formed in Short S2 also has illuminance not 100%. Since the ideal position coordinates of the out-box mark 92 in FIG. 4 and the in-box mark 94 in FIG. 5 are the same, these marks are formed in the positional relationship of insertion, so that they are aligned with the mark 96 shown in FIG. 6. As a result, the second position misalignment amount, which is the amount of position misalignment between short S1 and short S2, is measured. The out-box mark 92 and the in-box mark 94 can adopt the gray tone box-in-box mark shown in FIG. 7. By studying the exposure light transmittance of each mark on the mask, the amount of positional deviation between shot S1 and shot S2 can be measured with high precision. In addition, details of the gray tone box-in-box mark are disclosed, for example, in Japanese Patent Laid-Open No. 2018-10211.

The amount of positional deviation in the In other words, Δ2 represents the amount of positional deviation of shot S1 with respect to the lower layer. Additionally, the amount of positional deviation in the In other words, Δ2 represents the amount of positional deviation of shot S2 with respect to the lower layer. Then, in S102, the composite in-box mark 95 of the upper layer, which has a total illumination of 100% by connecting the left and right shots, is the amount of deviation in the X direction with respect to the out-box mark 91 of the lower layer. The one-position misalignment amount M1 is obtained by the following equation.

M1=((100-a)/100)·Δ1+(a/100)·Δ2 (1)

In addition, from the mark 96, a second position deviation amount (left and right shot arrangement deviation amount) of the in-box mark 94 exposed by shot S2 with respect to the out-box mark 92 exposed by shot S1 M2 is obtained by the following equation (S102).

M2=Δ1-Δ2 (2)

Here, to simplify the explanation, consider the case where the In this case, because a=50%, equation (1) becomes:

M1=(Δ1+Δ2)/2 (3)

From equations (2) and (3), Δ1 and Δ2 are as follows.

Δ1=M1+(M2/2) (4)

Δ2=M1-(M2/2) (5)

Accordingly, the positional deviation amount obtained by adding a predetermined ratio (for example, 50%) of the second positional deviation amount M2 to the first positional deviation amount M1 is defined as the correction amount of the first image of shot S1 in the connection area. It can be decided as In addition, the positional deviation amount obtained by subtracting the remaining ratio (for example, 100% - 50% = 50%) to the above predetermined ratio of the second positional deviation amount M2 from the first positional deviation amount M1 is defined as the connection area. It can be determined as the correction amount of the second image of shot S2 in . The above explanation can be generalized in the case where the X position x1 at which each mark in the connection area is formed is arbitrary.

Here, using the positional deviation amount obtained from the result of the first exposure (S101), the correction amount of X position x1 by exposure of shot S1 is,

M1+(a/100)·M2 (6)

Do it as In addition, using the positional deviation amount obtained from the first exposure result, the correction amount of X position x1 by exposure of shot S2 is,

M1-((100-a)/100)·M2 (7)

Do it as

Then, the correction amount in the X direction of the upper and lower layers at the

((100-a)/100)×(M1+(a/100)·M2)+(a/100)×(M1+((100-a)/100)·M2) (8)

Substituting equations (1) and (2) into equation (8), it becomes as follows.

((100-a)/100)·{((100-a)/100)×Δ1+(a/100)×Δ2+a(Δ1-Δ2)/100}+(a/100)·{((100 -a)/100)×Δ1+(a/100)×Δ2-(100-a)(Δ1-Δ2)/100}

=(100-a)/100 ×Δ1+a/100×Δ2 (9)

In addition, the correction amount in the

(M1+(a/100)·M2)-(M1-((100-a)/100)·M2)

=(((100-a)/100)·Δ1+(a/100)·Δ2+a(Δ1-Δ2)/100)

-(((100-a)/100)·Δ1+(a/100)·Δ2-(100-a)(Δ1-Δ2)/100)

= Δ1-Δ2 (10)

As an effect after the above correction, correction without correction residual can be performed in the second exposure (S104) as shown below.

· Overlay of upper and lower layers

Amount of misalignment in the first exposure: (100-a)/100)·Δ1+(a/100)·Δ2

Correction amount during second exposure: (100-a)/100·Δ1+(a/100)·Δ2

⇒ Correction residual: 0

·Alignment of left and right shots is misaligned

Amount of deviation of the first exposure: Δ1-Δ2

Correction amount of second exposure: Δ1-Δ2

⇒ Correction residual: 0

However, depending on production conditions such as process characteristics and mask manufacturing cost, there are cases where the mark cannot be placed in the connection area as in Example 1 above. At that time, the misalignment of the upper and lower layers in the connection area and the misalignment of the left and right shot arrangements cannot be directly detected from the measurement results of the mark. In the following Examples 2 and 3, based on the positional misalignment information detected from marks outside the connected area, the misalignment of the upper and lower layers and the left and right shot arrangement misalignment within the connected area are estimated, and the correction method of Example 1 can be used. Explain an example of how to do this.

(Example 2)

As shown in Fig. 8, the layout of the exposure shots is the same as in Example 1. At a position outside the connection area in the shot S1, a mark C1 (connection position measurement mark on the first shot area side) is formed that can detect deviation of the absolute position of a specific portion of the shot. Additionally, a mark B1 (overlapping mark on the first shot area side) that can detect relative positional deviation of the upper and lower layers at a specific location is also formed at a position other than the connection area in shot S1. Similarly, a mark C2 (connection position measurement mark on the second shot area side) is formed at a position outside the connection area in shot S2, which can detect deviation of the absolute position of a specific portion of the shot. Additionally, a mark B2 (overlapping mark on the second shot area side) that can detect relative positional deviation of the upper and lower layers at a specific location is also formed at a position other than the connection area in shot S2.

The arrangement positions of the marks C1 and C2 within the shot are adjusted so that the center position of the abnormal positions of the marks C1 and C2 formed after the connection exposure is within the connection area. At this center position, a virtual mark C3 (second virtual mark) is set for the purpose of detecting the relative position misalignment of the exposure results of shot S1 and shot S2 at the center position.

Similarly, the arrangement positions of marks B1 and B2 within the shot are adjusted so that the center position of the abnormal positions of marks B1 and B2 formed after connection exposure is within the connection area. At this center position, a virtual mark B3 (first virtual mark) is set for the purpose of detecting the relative positional misalignment of the lower layer and the connected composite exposure result of shot S1 and shot S2 at this center position.

When the detection amounts of virtual mark C3 and virtual mark B3 are respectively obtained, the same correction method as in Example 1 can be used. The detection amount Q _C3 of the virtual mark C3 is estimated from the detection amount Q _C1 of the mark C1 and the detection amount Q _C2 of the mark C2 by the following equation.

Q _C3 =Q _C1 -Q _C2

Similarly, the detection amount Q _B3 of the virtual mark B3 is estimated from the detection amount Q _B1 of the mark B1 and the detection amount Q B2 of the mark _B2 by the following equation.

Q _B3 =(Q _B1 +Q _B2 )/2

As described above, according to this embodiment, the first virtual mark is set at a position in the connection area between the overlapping mark on the first shot area side and the overlapping mark on the second shot area side. Then, the amount of positional misalignment of the first virtual mark is estimated based on the amount of positional misalignment between the overlapping marks on the first shot area side and the amount of positional misalignment between the overlapping marks on the second shot area side, and this estimated amount of positional misalignment is It is obtained as the first position misalignment amount. Additionally, a second virtual mark is set at a position in the connection area between the connection position measurement mark on the first shot area side and the connection position measurement mark on the second shot area side. Then, the amount of positional misalignment of the second virtual mark is estimated based on the amount of positional misalignment between the connection position measurement marks on the first shot area side and the amount of positional misalignment between the connected position measurement marks on the second shot area side, and this estimated positional misalignment is The amount is obtained as the second position misalignment amount.

In addition, in Figure 8, a mark for detecting a deviation in the absolute position of a specific point of a shot and a mark for detecting a deviation in the relative position of the upper and lower layers of a specific point are arranged near the connection area, and marks of the same type for other shots are placed in the vicinity of the connection area. It is arranged to be symmetrical from the center line of the connection area. However, the present invention is not limited to this arrangement.

(Example 3)

Furthermore, as shown in Fig. 9, when a plurality of marks for detecting deviation of the absolute position of a specific point of the shot are arranged on an arbitrary straight line in each shot of shot S1 and shot S2, the virtual mark is in the connection area. It is possible to place it in a straight line. The distances from marks C10, C11, C20, and C21 to virtual mark C30 are set to D10, D11, D20, and D21, respectively. Additionally, the detection amounts of marks C10, C11, C20, and C21 are set to Q _C10 , Q _C11 , Q _C20 , and Q _C21 , respectively. In this case, the detection amount Q _C30 of the virtual mark C30 is estimated by the following equation.

Q _C30 =

[((Q _C11 -Q _C10 )/(D11-D10))×D11+Q _C11 ]-

[((Q _C21 -Q _C20 )/(D21-D20))×D21+Q _C21 ]

Similarly, when multiple marks are placed in each shot of Shot S1 and Shot S2 to detect relative positional deviation of the upper and lower layers at a specific point on an arbitrary straight line, the virtual mark is placed at a point on the straight line in the connection area. It is possible. The distances from marks B10, B11, B20, and B21 to virtual mark B30 are set to E10, E11, E20, and E21, respectively. Additionally, the detection amounts of marks B10, B11, B20, and B21 are set to Q _B10 , Q _B11 , Q _B20 , and Q _B21 , respectively. In this case, the detection amount Q _B30 of the virtual mark B30 is estimated by the following equation.

Q _B30 =

{[(Q _B11 -Q _B10 )/(E11-E10)×E11+Q _B11 ]+

[(Q _B21 -Q _B20 )/(E21-E20)×E21+Q _B21 ]}/2

In the method shown in Fig. 9, the detection amount of the virtual mark is obtained by linear interpolation from the detection amount of the arranged marks, but the method is not limited to this. It may also be obtained using other general statistical methods.

In each of the above-described embodiments, one upper and lower layer detection mark or its virtual mark and one left and right shot alignment misalignment detection mark or its virtual mark in the connection area are respectively disposed, but the present invention is not limited thereto. A plurality of upper and lower layer detection marks or their virtual marks and left and right shot alignment misalignment detection marks or their virtual marks in the connection area may be respectively arranged.

<Second Embodiment>

As shown in FIG. 1, the exposure apparatus in the embodiment is equipped with an alignment scope 80 and an off-axis scope 81. In this embodiment, marks exposed on the substrate are measured by both the alignment scope 80 and the off-axis scope 81, and the measurement data is stored in the data holding unit 71. Calibration processing is performed on the alignment scope 80 and the off-axis scope 81 by the control unit 70, and is adjusted so that when measuring the same mark, the measured values are the same no matter which scope is used. Here, by measuring the marks formed on the original plate 30 and the substrate 60 before exposure, measurement of Δ1 and Δ2 described in Example 1 becomes possible. Even by using this method, the examples in the first embodiment can be realized.

<Embodiment of product manufacturing method>

The method of manufacturing an article according to an embodiment of the present invention is also suitable for manufacturing articles such as micro devices such as semiconductor devices or elements having a micro structure. The method of manufacturing an article of this embodiment includes a process of forming a latent image pattern on a photosensitive agent applied to a substrate (a process of exposing the substrate) using the above-described pattern formation method or a lithography apparatus, and a substrate on which the latent image pattern was formed through this process. Includes processing (development) process. Moreover, this manufacturing method includes other well-known processes (oxidation, film formation, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The product manufacturing method of this embodiment is advantageous compared to the conventional method in at least one of product performance, quality, productivity, and production code.

(Other Embodiments)

The present invention provides a program that realizes one or more functions of the above-described embodiments to a system or device through a network or storage medium, and one or more processors in a computer of the system or device reads and executes the program. It is also feasible in processing. Additionally, it can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist.

10: illumination optical system, 20: slit imaging system, 30: original plate, 40: projection optical system, 60: substrate, 70: control unit

Claims (9)

A first image is formed by exposing a first shot area of the substrate, a second image is formed by exposing a second shot area overlapping a portion of the first shot area, and the first image and the second image are formed. A determination method for determining a correction amount regarding alignment of the first shot area and the second shot area for connection exposure to obtain an image in which two images are connected to each other,
By exposing the first shot area, a first mark is placed on a connection area where the first shot area and the second shot area overlap for alignment with a base mark formed on a lower layer of the connection area; Forming a second mark for alignment between the first shot area and the second shot area,
By exposing the second shot area, a third mark is formed to overlap the first mark for alignment with the base mark, and a third mark is formed at a position overlapping with the second mark in the connection area. Form 4 marks,
Obtaining the amount of positional deviation of the composite mark formed by overlapping the first mark and the third mark with respect to the base mark as the first positional deviation amount,
Determine the amount of positional deviation of the fourth mark with respect to the second mark as the second positional deviation amount,
The positional deviation amount obtained by adding a predetermined ratio of the second positional deviation amount to the first positional deviation amount is expressed as the first image in the connection area where the first shot area and the second shot area overlap. Determined as a correction amount,
Determining the positional deviation amount obtained by subtracting the remaining ratio for the predetermined ratio of the second positional deviation amount from the first positional deviation amount as the correction amount of the second image in the connection area,
The ground mark, the first mark, the second mark, the third mark, and the fourth mark are each in the direction of the overlap width between the first shot area and the second shot area in the connection area. is formed at a position that does not include both ends of
The predetermined ratio is the base mark, the first mark, the second mark, the third mark, and A determination method, characterized in that the ratio is based on the position of the fourth mark.
According to claim 1,
The ground mark, the first mark, the second mark, the third mark, and the fourth mark are each in the direction of the overlap width between the first shot area and the second shot area in the connection area. A decision method characterized in that it is installed in the center of.
According to claim 1,
A determination method, characterized in that the predetermined ratio is 50%. According to claim 1,
Crossfade the exposure amount in the connection area when exposing the first shot area and when exposing the second shot area so that the illuminance distribution from the first shot area to the second shot area is equalized. A decision method characterized by making a decision.
delete A first process of forming a first image by exposing a first shot area of the substrate;
A second process of forming a second image by exposing a second shot area overlapping a portion of the first shot area,
An exposure method for obtaining an image in which the first image and the second image are connected to each other,
In the first step, the correction amount of the first image determined by the determination method according to any one of claims 1 to 4 is the correction amount in the connection area overlapping the second shot area of the first shot area. correct the first image,
In the second process, the second image in the connection area is corrected by a correction amount of the second image determined by the determination method according to any one of claims 1 to 4. method.
A first image is formed by exposing a first shot area of the substrate, a second image is formed by exposing a second shot area overlapping a portion of the first shot area, and the first image and the second image are formed. An exposure apparatus that performs connected exposure to obtain an image in which two images are connected to each other,
a processing unit that performs processing to determine a correction amount related to alignment of the first shot area and the second shot area;
It has a control unit that controls the connected exposure,
The processing unit,
By exposing the first shot area, a first mark is placed on a connection area where the first shot area and the second shot area overlap for alignment with a base mark formed on a lower layer of the connection area; Forming a second mark for alignment between the first shot area and the second shot area,
By exposing the second shot area, a third mark is formed to overlap the first mark for alignment with the base mark, and a third mark is formed at a position overlapping with the second mark in the connection area. Form 4 marks,
Obtaining the amount of positional deviation of the composite mark formed by overlapping the first mark and the third mark with respect to the base mark as the first positional deviation amount,
Determine the amount of positional deviation of the fourth mark with respect to the second mark as the second positional deviation amount,
The positional deviation amount obtained by adding a predetermined ratio of the second positional deviation amount to the first positional deviation amount is expressed as the first image in the connection area where the first shot area and the second shot area overlap. Determined as a correction amount,
Determining the positional deviation amount obtained by subtracting the remaining ratio for the predetermined ratio of the second positional deviation amount from the first positional deviation amount as the correction amount of the second image in the connection area,
The ground mark, the first mark, the second mark, the third mark, and the fourth mark are each in the direction of the overlap width between the first shot area and the second shot area in the connection area. is formed at a position that does not include both ends of
The predetermined ratio is the base mark, the first mark, the second mark, the third mark, and It is a ratio according to the position of the fourth mark,
The control unit,
The first image in the connection area is corrected with the determined correction amount of the first image, and the second image in the connection area is corrected with the determined correction amount of the second image. Then, the connection exposure is performed,
The predetermined ratio is an attenuation rate of the exposure amount at the position of the overlap mark and the connection position measurement mark in the direction of the overlap width of the first shot area and the second shot area in the connection area. exposure device.
delete A process of exposing a substrate using the exposure method according to claim 6,
The process includes developing the exposed substrate,
A method of manufacturing an article, characterized in that an article is produced from the developed substrate.

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