KR20200075742A - Determination method, exposure method, exposure apparatus and method of manufacturing article - Google Patents

Abstract

The present invention provides a connecting exposure technique advantageous for achieving both overlap precision of upper and lower layers and a connecting precision of an adjacent shot. In particular, the present invention relates to a determination process for forming a first image by exposing a first shot region of a substrate, forming a second image by exposing a second shot region overlapped with a portion of the first shot region, and determining a correction amount with respect to position alignment of the first shot region and the second shot region for connecting exposure to obtain an image in which the first image and the second image are interconnected. According to the determination process: a first position deviation amount, which is a position deviation amount between overlap masks for overlapping the upper and lower layers, is obtained; a second position deviation amount, which is a position deviation amount between connection position measurement marks for performing a position alignment of the first shot region and the second shot region, is obtained; a position deviation amount obtained by adding a certain portion of the second position deviation amount to the first position deviation amount is determined as a correction amount of the first image in a connecting region overlapped by the first shot region and the second shot region; and a position deviation amount obtained by subtracting the remaining portion of the second position deviation amount from the first position deviation amount is determined as a correction amount of the second image in the connecting region.

Description

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, and the like are manufactured by a photolithography process. In the photolithography process, a scanning exposure apparatus is used in which a pattern of a disk (mask) is projected while scanning an exposure area onto a substrate (glass substrate or wafer) coated with a photosensitive agent through a projection optical system. In recent years, the enlargement of displays such as liquid crystal panels has progressed, and for example, it is necessary to perform exposure to a glass substrate that seems to exceed 2m angle. In order to cope with such a large size of the substrate, rather than exposing all of the exposure area on the substrate at once, dividing the exposure area on the substrate into several short areas is performed. At this time, the connection exposure is performed by overlapping and exposing a part of the adjacent short areas.

In the connection exposure, when the overlay (overlapping) error in a region (connection region) where adjacent short regions are polymerized is large, spots are generated in the connection region. Patent Document 1 specializes in either the amount of positional displacement between the upper and lower layers in the connection region, or the amount of positional displacement between adjacent shots, obtains a correction amount to reduce the amount of the shift, and uses the correction amount to expose Technology is disclosed. In addition, Patent Document 2 discloses a technique for correcting a shot position by using a plurality of shots constituting one device as one unit. The correction of the shot position is performed such that the difference in the overlapping accuracy in the connecting portions of the plurality of shots constituting one device is minimized.

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

In the case of connecting exposure, the positional deviation between adjacent shots is the most important index for determining the performance of the device to be manufactured. Nevertheless, in the conventional correction, only the amount of positional deviation between upper and lower layers is corrected, and the positional deviation between adjacent shots is not considered, or only the amount of positional deviation between adjacent shots is corrected, and the positional deviation between upper and lower layers is not considered. . On the other hand, a method of preferentially correcting the positional deviation between adjacent shots (connection priority correction) has also been proposed. According to the method, the effect of correcting the positional deviation between the upper and lower layers is reduced, but the required precision of the connection exposure so far has been satisfied.

However, with the increase in size of the substrate and the miniaturization of the pattern, there is an increasing demand to guarantee both the superposition accuracy of the upper and lower layers and the connection accuracy of adjacent shots together with high precision. In other words, there is a demand for a method of correcting the misalignment of the upper and lower layers and the positional misalignment between adjacent shots with high precision.

An object of the present invention is to provide a technique of connecting exposure, which is advantageous for achieving both the overlapping accuracy of the upper and lower layers and the joining accuracy of adjacent shots.

According to one aspect of the present invention, the first shot region of the substrate is exposed to form a first image, and the second shot region overlapping a part of the first shot region is exposed to form a second image, A method of determining a correction amount for the alignment of the first shot region and the second shot region for connection exposure to obtain an image in which the first image and the second image are connected to each other, comprising: The first position shift amount, which is the position shift amount between the overlapping marks for performing overlapping, is determined, and the second position is the position shift amount between the connection position measurement marks for aligning the first shot area and the second shot area. In the connection region in which the first shot region and the second shot region overlap the amount of positional deviation obtained by obtaining a displacement amount and adding a predetermined ratio of the second location displacement amount to the first location displacement amount. It is determined as the correction amount of the first image, and the position shift amount obtained by subtracting the remaining ratio of the second position shift amount to the predetermined ratio of the second position shift amount is the first shift in the connection area. A determination method is provided, which is characterized in that it is determined as a correction amount of a phase of 2.

ADVANTAGE OF THE INVENTION According to this invention, the technique of the connection exposure which is favorable for the compatibility of the overlapping precision of a top and bottom layer and the connection precision of an adjacent shot can be provided.

1 is a diagram showing the configuration of an exposure apparatus in an embodiment.
[Fig. 2] Fig. 2 is a diagram showing an example of an illuminance distribution at the time of connecting exposure.
3 is a flowchart of a process for determining a correction amount and an exposure process.
[Fig. 4] Fig. 4 is a diagram showing an example of a mark arrangement in short S1.
[Fig. 5] Fig. 5 is a diagram showing an example of a mark arrangement in short S2.
6 is a diagram showing an example of a superimposition mark and a connection position measurement mark in a connection area.
7 is a diagram showing an example of a connection position measurement mark.
Fig. 8 is a diagram showing an example of a virtual mark set in the connection area.
9 is a diagram showing an example of a virtual mark set in the connection area.

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

<First Embodiment>

Fig. 1 shows a schematic configuration of an exposure apparatus in the 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 the present specification and drawings, the direction in the coordinate system in which the direction parallel to the substrate holding surface by the substrate stage is set to be the ＸＹ plane is shown. The directions parallel to the X-axis, Y-axis, and Z-axis in the coordinate system are referred to as X-direction, Y-direction, and Z-direction. In addition, the scanning direction of the original plate and the substrate during exposure is set as the Y direction.

The exposure apparatus includes an original stage 30 on which the original plate 30 (mask) is mounted, a substrate stage 61 on which the substrate 60 (for example, a glass plate) is mounted, and an illumination illuminating the original plate 30. And 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 arranged at positions optically conjugated through the projection optical system 40 (the object surface and the upper surface of the projection optical system 40). Between the illumination optical system 10 and the disc stage 31, a slit imaging system 20 for shaping the exposure light is arranged. In addition, when scanning exposure of the substrate 60, the light shielding plate 50 for sequentially exposing a portion of each other on the pattern of the original plate 30 on another area of the surface of the substrate 60 in order to expose the projection optical system ( 40) and the substrate stage 61. The control unit 70 controls driving of each part of the exposure apparatus.

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

The original plate stage 31 on which the original plate 30 is mounted is scanned in the Y direction by a driving mechanism (not shown) under control by the control unit 70. A plurality of reflectors 32 are disposed on the original stage 31. Each of the plurality of reflectors 32 reflects the measurement light from the interferometer 33 disposed outside the original stage 31. The interferometer 33 receives the reflected measurement light, and constantly monitors and measures the position of the disc stage 31. The control unit 70 controls the position and speed of the disc stage 31 based on the result of the measurement by the interferometer 33.

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

In the exposure apparatus in this embodiment, the first shot region of the substrate is exposed to form the first image, and the second shot region overlapping with a part of the first shot region is exposed to form the second image. , Connected 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-shielding plate 50 in order to perform this connection exposure. In addition, in the following description, "short area" is also referred to simply as "short". The X light blocking plate 50 may be driven in the Y direction by a driving mechanism (not shown) under control by the control unit 70. By changing the position where the light is shielded by moving the X light-shielding plate 50 horizontally in the exposure optical path, the exposure light shaped by the slit imaging system 20 is obliquely blocked with respect to the scanning direction, thereby accumulating on the substrate The exposure amount to be controlled is controlled. Accordingly, it is possible to control the connection exposure to the connection short layout shown in FIG. 2A. In other words, as shown in Fig. 2B, the illuminance distribution of the non-connected region, which is an area other than the connected region in the short S1 (first shot region), is 100%, and the illuminance distribution at each X position in the connected region is negative. The slope. For example, the exposure amount (illuminance) is linearly attenuated from 100% to 0% from one end to the other end in the Ｘ direction of the connection region. In addition, as shown in FIG. 2C, the illuminance distribution of the unconnected region of the short S2 (second shot region) is set to 100%, and the illuminance distribution of each X position of the connected region is defined as a positive slope. For example, the exposure amount is linearly increased from 0% to 100% from one end to the other end in the Ｘ direction of the connection region. Thus, when exposing the shot S1 and exposing the shot S2, the exposure amount in the connection region is crossfaded. Accordingly, as shown in FIG. 2D, the illuminance distribution of integration for the connected and non-connected regions is leveled to 100%.

The substrate stage 61 on which the substrate 60 is mounted is scanned in the X, Y and Z directions by a driving mechanism (not shown) under control by the control unit 70. The substrate stage 61 is provided with a plurality of reflectors 62. Each of the plurality of reflectors 62 reflects the 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 result 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 under 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 for determining a correction amount related to the alignment of the shots S1 and S2, and also functions as a control unit that controls connection exposure. The control unit 70 may include, as its functional configuration, a data holding unit 71, a driving amount calculating unit 72, and a driving instruction unit 73. The data holding unit 71 is a driving parameter, such as the distance of one or more points in the shot measured from the mark exposed on the substrate by the exposure apparatus, the amount of displacement in the Y direction, the drive offset of each drive shaft, the sensitivity, etc. It holds various acquired measurement data. The driving amount calculating section 72 calculates various correction components such as position offset, rotation, and magnification in the X, Y, and Z directions using general statistical methods from the data held in the data holding section 71. Further, the driving amount calculating section 72 determines the driving instruction amount for each axis based on the driving parameter and the calculated correction component. The drive instruction unit 73 outputs a drive instruction for each drive mechanism by using the drive instruction amount for each drive mechanism determined by the drive amount calculation unit 72. Further, 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 is realized by a memory, and the driving amount calculating unit 72 and the driving instruction unit 73 can be realized by a CPU.

(Example 1)

With reference to the flowchart of Fig. 3, the outline of the processing for determining the correction amounts for the alignment of the shots S1 and S2 for connection exposure in this embodiment and the exposure processing performed based on the determined correction amount will be described. First, the first connection exposure is performed on the shots S1 and S2 (S101). This first connection exposure is exposure for determining the correction amount. The substrate used at this time may be a substrate for production or a substrate for testing. Next, the overlapping (overlay) error of the upper and lower layers in the connection region and the positional shift (short-left and right-sided array shift) of the short S1 and short S2 are measured (S102). This measurement may be performed using a measurement device outside the exposure apparatus, or may be performed using an alignment scope 80 or an off-axis scope 81.

Based on this measurement result, the control unit 70 calculates (determines) the correction amount (S103). The calculated correction amount is stored in the data holding unit 71 as a correction parameter at the time of exposure, for example. As the correction parameters, there are shifts, rotations, magnifications, etc. of the shot area, and control data such as a stage or an optical system as control objects of the exposure apparatus, and the calculated correction amounts can be converted into correction values suitable for these parameters.

Thereafter, the second exposure (next linked exposure) is performed. The second exposure referred to herein may be the main exposure using a substrate for production (S104). Here, the control unit 70 reflects the correction value to perform connection exposure.

Hereinafter, a determination method for determining correction amounts for the alignment of the shots S1 and S2 according to the above S101 to S103 will be described in detail. 4 is a schematic diagram of the shot S1 exposed in S101. In the present embodiment, the measurement for overlapping the upper and lower layers and the measurement for the alignment of the shots S1 and S2 are performed using, for example, a box in-box mark. In Fig. 4, the outer box mark 91 (underground mark) constituting the overlapping mark is already formed on the layer below the connection region. In the case of exposure of the shot S1, an inbox mark 90 (first mark) for alignment with the outbox mark 91 is formed. Further, in the case of exposure of the shot S1, the outbox mark 92 (second mark), which is a connection location measurement mark for alignment of the shot S1 and the shot S2, is also formed in the connection region.

As described above, in the shot S1, the exposure amount (illuminance) is attenuated linearly from 100% to 0% from one end to the other end in the Ｘ direction of the connection region. As shown in Fig. 4, each mark formed in the connection region is disposed at a predetermined position x1 in the direction (X direction) of the overlapping width between the shot S1 and the shot S2, and the exposure amount at the position x1 Let the damping rate of be a%. A superimposition error (overlay error) is detected from a difference in position between the outbox mark 91 formed in the lower layer and the inbox mark 90 formed in the upper layer. However, since the roughness of the position x1 is only (100-a)% at the time when the shot S1 is exposed, the inbox mark 90 and the outbox mark 92 are not formed completely.

5 is a schematic diagram of the shot S2 exposed in S101. At the time of exposure of the shot S2, the inbox mark 93 (third mark) is formed so as to overlap with the inbox mark 90 for alignment with the outbox mark 91, which is the bottom background mark. In addition, during exposure of the shot S2, the inbox mark 94 (fourth mark), which is a connection position measurement mark for alignment of the shot S1 and the shot S2, is also formed at a position overlapping the outbox mark 92. A superimposition error may be detected from a difference in position between the outbox mark 91 formed in the lower layer and the inbox mark 93 formed in the upper layer. However, since the illuminance at the position x1 when the shot S2 is exposed is a%, the total illuminance with the inbox mark 90 in Fig. 4 having the same abnormal position coordinate is (100-a)+a=100%. It is formed entirely here. In this way, the in-box mark 90 and the in-box mark 93 are superimposed, and as shown in Fig. 6, a composite in-box mark 95 (composite mark) is formed. Accordingly, the amount of positional shift of the measured composite inbox mark 95 with respect to the outbox mark 91 is the first positional shift amount that is the amount of positional shift between the overlapping marks 91 and 95 for overlapping the upper and lower layers. As is obtained.

Similarly, the inbox mark 94 formed in the short S2 is not 100% rough. Since the out-of-box mark 92 in Fig. 4 and the in-box mark 94 in Fig. 5 have the same abnormal position coordinates, these marks are formed in the positional relationship of the fitting, and therefore, to the mark 96 shown in Fig. 6 By this, the second position shift amount, which is the position shift amount between the short S1 and short S2, is measured. As the outbox mark 92 and the inbox mark 94, a gray tone box in box mark shown in Fig. 7 can be employed. By studying the exposure light transmittance of each mark on the mask, it is possible to accurately measure the amount of misalignment between shot S1 and shot S2. The details of the gray tone box in box mark are disclosed in, for example, Japanese Patent Laid-Open No. 2018-10211.

The amount of positional displacement in the Ｘ direction with respect to the outbox mark 91 that is the superimposition mark of the lower layer of the inbox mark 90 (FIG. 4), which is the superimposition mark of the upper layer, is set to Δ1. In other words, Δ2 represents the amount of position shift of the short S1 with respect to the lower layer. In addition, the amount of positional displacement in the Ｘ direction with respect to the outbox mark 91 which is the superimposition mark of the lower layer of the inbox mark 93 (FIG. 5) which is the superimposition mark of the upper layer is set to Δ2. In other words, Δ2 represents the amount of position shift of the short S2 with respect to the lower layer. Then, in S102, the amount of shift in the direction of the direction of the composite inbox mark 95 of the upper layer, which is 100% of the total roughness by connecting the left and right shots to each other, in the direction of the 박스 direction with respect to the outbox mark 91 of the lower layer. The amount of displacement M1 in one position is obtained by the following equation.

M1=((100-a)/100)·Δ1+(a/100)·Δ2 (One)

In addition, the second position shift amount, which is the position shift amount (left and right shot array shift amount) of the inbox mark 94 exposed in short S2 with respect to the outbox mark 92 exposed in short S1 from mark 96 M2 is obtained by the following equation (S102).

M2=Δ1-Δ2 (2)

Here, for the sake of simplicity, consider the case where the position x1 in which each mark in the connection area is formed is set to the center of the connection area (center of the overlapping width direction of shot S1 and shot S2). In this case, since a=50%, equation (1) becomes as follows.

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 amount of position shift obtained by adding a predetermined ratio (for example, 50%) of the second position shift amount M2 to the first position shift amount M1 is the correction amount of the first image of the short S1 in the connection region. Can be determined as In addition, the positional shift amount obtained by subtracting the remaining ratio (for example, 100%-50% = 50%) of the second position shift amount M2 from the first position shift amount M1 to the predetermined ratio is a connection area. It can be determined as the correction amount of the second image of the shot S2 in. The above description can be generalized when the position x1 in which each mark in the connection region is formed is arbitrarily set.

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

M1+(a/100)·M2 (6)

Should be Further, using the amount of positional deviation obtained from the first exposure result, the correction amount of the position x1 by exposure of the shot S2 is

M1-((100-a)/100)M2 (7)

Should be

Then, the correction amount in the Ｘ direction of the upper and lower layers at the X position x1 is as follows by using equations (6) and (7).

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

Substituting equations (1) and (2) into this equation (8), we get:

((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 Ｘ direction of the mark 96 which is a measurement mark of the left and right short alignment misalignment connected to each other is as follows.

(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 the effect after the correction, the second exposure (S104) can perform correction without a correction residual as follows.

· Top and bottom layer overlay

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

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

⇒ Correction residual: 0

·Left and right shot alignment misalignment

Displacement amount of first exposure: Δ1-Δ2

Correction amount of the second exposure: Δ1-Δ2

⇒ Correction residual: 0

However, depending on the production conditions such as process characteristics and mask manufacturing cost, as in the first embodiment described above, there may be cases where the mark cannot be placed in the connection region. At this time, it is not possible to directly detect the misalignment of the upper and lower layers in the connection region and the misalignment of the left and right shots from the measurement result of the mark. In the following Example 2 and Example 3, based on the positional deviation information detected from the mark outside the connection area, it is possible to estimate the deviation of the top and bottom layers in the connection area and the left and right shot arrangement deviation, and the correction method of Example 1 can be used. Here is an example of how to do it.

(Example 2)

As shown in Fig. 8, the layout of the exposure shot is the same as in Example 1. A mark C1 (connected position measurement mark on the first shot area side) capable of detecting a shift in the absolute position of a specific location of the shot is formed at a position outside the connection area in the shot S1. In addition, a mark B1 (overlapping mark on the first shot area side) capable of detecting the relative positional deviation of the upper and lower layers at a specific location is also formed at a position outside the connection area in the shot S1. Similarly, a mark C2 (connected position measurement mark on the second shot area side) capable of detecting a shift in the absolute position of a specific location of the shot is formed at a position outside the connection area in the shot S2. In addition, a mark B2 (overlapping mark on the second shot region side) capable of detecting the relative positional deviation of the upper and lower layers at a specific location is also formed at a position outside the connecting region in the shot S2.

The positions in the shots of the marks C1 and C2 are adjusted so that the center positions of the abnormal positions of the marks C1 and C2 formed after the connection exposure are in the connection area. To this central position, a virtual mark C3 (second virtual mark) for the purpose of detecting the relative positional deviation of the exposure result of the shots S1 and S2 at the center position is set.

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

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

Q _C3 =Q _C1 -Q _C2

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

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

As described above, according to this embodiment, the first virtual mark is set at the position in the connection region between the superimposition mark on the first shot region side and the superimposition mark on the second shot region side. Then, the amount of positional deviation of the first virtual mark is estimated based on the amount of positional deviation between the overlapping marks on the first shot area side and the amount of positional displacement between the overlapping marks on the second shot area side, and the estimated amount of positional displacement It is calculated as the amount of displacement in the first position. Further, 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 position shift of the second virtual mark is estimated based on the amount of position shift between the connection position measurement marks on the first shot area side and the amount of position shift between the connection position measurement marks on the second shot area side, and this estimated position shift The amount is obtained as the amount of displacement in the second position.

In addition, in Fig. 8, a mark for detecting the displacement of the absolute position of a specific location of the shot and a mark for detecting the relative displacement of the upper and lower layers of the specific location are arranged in the vicinity of the connection area, and marks of the same type of other shots are displayed. They are arranged to be symmetrical at the centerline of the connection area. However, the present invention is not limited to this arrangement.

(Example 3)

Further, as shown in Fig. 9, when a plurality of marks for detecting the misalignment of the absolute position of a specific position of a shot are placed on each straight line in each shot of the shots S1 and S2, the virtual mark is within the connection area. It can be arranged at a straight line. The distances from the marks C10, C11, C20, and C21 to the virtual mark C30 are set to D10, D11, D20, and D21, respectively. In addition, the detection amounts of the marks C10, C11, C20, and C21 are 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, in the shots S1 and S2, if a plurality of marks for detecting the relative positional misalignment of the upper and lower layers of a specific location is placed in an arbitrary straight line, the virtual mark is placed at a straight line in the connection area. It is possible to do. The distances from the marks B10, B11, B20, and B21 to the virtual mark B30 are taken as E10, E11, E20, and E21, respectively. In addition, the detection amounts of the 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 determined by linear interpolation from the detection amount of the placed marks, but is not limited to this. It may also be obtained by other statistical methods.

In each of the above-described embodiments, the mark for detecting the upper and lower layers in the connection region or its virtual mark and the left and right shot misalignment detection mark or its virtual mark are respectively disposed, but are not limited thereto. A plurality of upper and lower layer detection marks in the connection region or their virtual marks and left and right shot misalignment detection marks or their virtual marks may be placed respectively.

<Second Embodiment>

As shown in Fig. 1, the exposure apparatus in the embodiment includes an alignment scope 80 and an off-axis scope 81. In this embodiment, the 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. The alignment scope 80 and the off-axis scope 81 are calibrated by the control unit 70, and are adjusted so that the measured values are the same even when measured with either scope when measuring the same mark. Here, by measuring marks formed on the original plate 30 and the substrate 60 before exposure, it is possible to measure Δ1 and Δ2 described in Example 1. Even by using this method, the embodiment in the first embodiment can be realized.

<The embodiment of the article manufacturing method>

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

(Other embodiments)

The present invention provides a program that realizes one or more functions of the above-described embodiments to a system or device via a network or storage medium, and one or more processors in the computer of the system or device read and execute the program. It is also feasible in processing. Also, it can be realized by a circuit (e.g., ASIC) that realizes one or more functions.

The embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made 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 (8)

A first image is formed by exposing the first shot region of the substrate, and a second image is formed by exposing a second shot region overlapping a part of the first shot region, and the first image and the second image are formed. As a determination method for determining a correction amount regarding the alignment of the first shot region and the second shot region for connecting exposure to obtain an image in which two images are connected to each other,
The first positional shift amount, which is the amount of positional shift between the overlapping marks for stacking the upper and lower layers, is obtained,
A second position shift amount, which is a position shift amount between the connection position measurement marks for aligning the first shot area and the second short area, is obtained,
The first top in the connection area where the first shot area and the second shot area overlap the positional deviation amount obtained by adding a predetermined ratio of the second position deviation amount to the first position deviation amount. Determined as the correction amount,
The positional shift amount obtained by subtracting the remaining ratio of the second position shift amount to the predetermined ratio from the first position shift amount is determined as a correction amount of the second image in the connection region. To do, how to decide.
According to claim 1,
Exposing the first shot area, the first mark for alignment with the base mark formed on the lower layer of the connection area, and the first shot area and the second shot area in the connection area Form a second mark for alignment,
Exposing the second shot area, forming a third mark to overlap the first mark for alignment with the underlying mark, and removing the third mark from a position overlapping the second mark in the connection area. Form 4 marks,
The amount of positional displacement of the composite mark formed by overlapping the first mark and the third mark with respect to the wheat-based mark is determined as the first positional displacement,
And determining the amount of the positional displacement of the fourth mark relative to the second mark as the amount of the second positional displacement.
According to claim 1,
The superimposition mark and the connection position measurement mark are respectively formed at a position outside the connection area in the first shot area and a position outside the connection area in the second shot area,
A first virtual mark is set at a position in the connection area between the overlapping mark on the side of the first shot area and the overlapping mark on the side of the second shot area, and between the overlapping marks on the side of the first shot area Based on the amount of position shift and the amount of position shift between the overlapping marks on the second shot area side, the position shift amount of the first virtual mark is estimated, and the estimated position shift amount is obtained as the first position shift amount ,
A second virtual mark is set at a position in the connection area between the connection position measurement mark on the side of the first shot area and the connection position measurement mark on the side of the second shot area, and the connection position on the side of the first shot area Based on the amount of position shift between the measurement marks and the position shift amount between the measurement marks of the connection positions on the side of the second shot area, the position shift amount of the second virtual mark is estimated, and the estimated position shift amount is the second position A determination method characterized in that it is determined as an amount of deviation.
According to claim 1,
Cross exposure the exposure amount in the connection area when exposing the first shot area and exposing the second shot area so that the illuminance distribution from the first shot area to the second shot area is leveled. Characterized in that, the decision method.
The method of claim 4,
The predetermined ratio is a ratio according to the position of the overlapping mark and the connection position measurement mark in the direction of overlapping width of the first shot region and the second shot region in the connection region. To do, how to decide.
A first step of exposing the first shot region of the substrate to form a first image,
A second step of exposing a second shot region overlapping a part of the first shot region to form a second image,
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, a correction amount of the first image determined by the determination method according to any one of claims 1 to 5, wherein the connection area overlaps with the second shot area of the first shot area. Correct the first phase,
In the second step, exposure is characterized in that the second image in the connection region is corrected with a correction amount of the second image determined by the determination method according to any one of claims 1 to 5. Way.
A first image is formed by exposing the first shot region of the substrate, and a second image is formed by exposing a second shot region overlapping a part of the first shot region, and the first image and the second image are formed. An exposure apparatus that performs linked exposure to obtain images in which two images are connected to each other,
A processing unit that performs processing for determining a correction amount related to the alignment of the first shot area and the second shot area;
It has a control unit for controlling the connection exposure,
The processing unit,
The first positional shift amount, which is the amount of positional shift between the overlapping marks for stacking the upper and lower layers, is obtained,
A second position shift amount, which is a position shift amount between the connection position measurement marks for aligning the first shot area and the second short area, is obtained,
The first top in the connection area where the first shot area and the second shot area overlap the positional deviation amount obtained by adding a predetermined ratio of the second position deviation amount to the first position deviation amount. Determined as the correction amount,
A positional shift amount obtained by subtracting the remaining ratio of the second positional shift amount to the predetermined ratio from the first positional shift amount is determined as a correction amount of the second image in the connection region,
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 region is corrected with the determined correction amount of the second image. Thus, the exposure apparatus, characterized in that for performing the connection exposure.
A step of exposing the substrate using the exposure method according to claim 6,
The process includes developing the exposed substrate,
A method for manufacturing an article, characterized in that the article is manufactured from the developed substrate.

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