Lithography apparatus, lithography method, and method for manufacturing articles

Abstract

This technology provides advantages for aligning the original plate and the circuit board. [Solution] A lithography apparatus for forming a pattern on a curable composition on a substrate using a master plate, comprising: a measuring unit that simultaneously images a first group of marks provided on the master plate and a second group of marks provided on the substrate, which are located within a single field of view, to acquire mark images and measure the relative positions of the first group of marks and the second group of marks; and a control unit that, while measuring the relative positions by the measuring unit, aligns the master plate and the substrate based on the relative positions, wherein the control unit adjusts the imaging conditions for each region containing the images of each mark in the first group of marks and the second group of marks.

Description

Technical Field

[0005] , ,

[0001] The present invention relates to a lithographic apparatus, a lithographic method, and a method of manufacturing an article.

Background Art

[0002] An imprint apparatus is a device that enables the transfer of a nano-scale fine pattern and is attracting attention as one of the mass-production lithographic apparatuses for semiconductor elements, liquid crystal display elements, magnetic storage media, etc. In an imprint apparatus, in order to accurately transfer the pattern of a mold (die) as a master onto an imprint material on a substrate, it is required to accurately align (align) the mold and the substrate.

[0003] In an imprint apparatus, generally, a die-to-die alignment method is adopted as an alignment method between the mold and the substrate. The die-to-die alignment method is an alignment method in which, for each shot region on the substrate, a mark on the mold side provided on the mold and a mark on the substrate side provided on the substrate are optically detected to correct a deviation in the positional relationship (relative position) between the mold and the substrate (see Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In aligning a mold with a substrate, a group of marks consisting of multiple types of marks is used as both the mold mark and the substrate mark to achieve a wide detection range. However, when measuring the relative position (positional misalignment) between the substrate mark group and the mold mark group, the optical characteristics of the individual marks constituting the mark group may differ. When detecting such marks simultaneously through the same optical system, it is not possible to adjust each mark to obtain a good image (detection signal), which may affect the accuracy of the mold-substrate alignment. Furthermore, even if the optical characteristics of the individual marks constituting the mark group are the same, a similar problem arises if there is unevenness in the light illuminating each mark.

[0006] This invention has been made in view of the problems of the prior art, and its exemplary objective is to provide a technique that is advantageous for aligning a master plate and a substrate. [Means for solving the problem]

[0007] To achieve the above objective, a lithography apparatus as one aspect of the present invention is a lithography apparatus for forming a pattern on a curable composition on a substrate using a master plate, comprising: a measuring unit that simultaneously images a first group of marks provided on the master plate and a second group of marks provided on the substrate that are within a single field of view to acquire mark images and measures the relative positions of the first group of marks and the second group of marks; and a control unit that, while measuring the relative positions by the measuring unit, aligns the master plate and the substrate based on the relative positions, wherein the control unit adjusts the imaging conditions for each region that includes the images of each mark of the first group of marks and the second group of marks.

[0008] Further objects or other aspects of the present invention will be revealed by embodiments described below with reference to the accompanying drawings. [Effects of the Invention]

[0009] According to the present invention, for example, it is possible to provide a technique that is advantageous for aligning a master plate and a substrate. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram showing the configuration of an imprint device as one aspect of the present invention. [Figure 2] This is a schematic diagram showing an example of the configuration of the measurement unit. [Figure 3] This diagram provides a detailed explanation of the configuration of the mold-side mark group and the substrate-side mark group. [Figure 4] This is a schematic diagram showing an example of a superimposed image acquired by the imaging unit. [Figure 5A] This is a schematic diagram showing an example of the configuration of the imaging unit. [Figure 5B] This is a schematic diagram showing an example of the configuration of the imaging unit. [Figure 5C] This is a schematic diagram showing an example of the configuration of the imaging unit. [Figure 5D] This is a schematic diagram showing an example of the configuration of the imaging unit. [Figure 5E] This is a schematic diagram showing an example of the configuration of the imaging unit. [Figure 6] This diagram illustrates the setting of the regions containing the images of each mark in the mold-side mark group and the substrate-side mark group in the superimposed image. [Figure 7] This diagram illustrates the setting of the regions containing the images of each mark in the mold-side mark group and the substrate-side mark group in the superimposed image. [Figure 8] This is a diagram illustrating the manufacturing method of an article. [Modes for carrying out the invention]

[0011] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0012] Figure 1 is a schematic diagram showing the configuration of an imprint apparatus 100 as one aspect of the present invention. The imprint apparatus 100 is a lithography apparatus used in the lithography process, which is a manufacturing process for devices such as semiconductor elements, liquid crystal display elements, and magnetic storage media, to form patterns on a curable composition on a substrate. The imprint apparatus 100 brings an imprint material (curable composition) placed (supplied or coated) on the substrate into contact with a mold, and applies curing energy to the imprint material to form a pattern on a cured material into which the pattern of the mold has been transferred. For example, the imprint apparatus 100 places an imprint material on a substrate, and cures the imprint material while a mold with a pattern (reliefs) formed on it is in contact with the imprint material on the substrate. Then, the imprint apparatus 100 widens the gap between the mold and the substrate and pulls the mold away from the cured imprint material on the substrate (demolition), thereby forming a pattern of the imprint material on the substrate. This series of processes performed by the imprint apparatus 100 is generally called "imprint processing".

[0013] The imprint material used is a material (curable composition) that hardens when curing energy is applied. The curing energy can be electromagnetic waves or heat. Electromagnetic waves include, for example, light selected from wavelengths between 10 nm and 1 mm, specifically infrared rays, visible light, and ultraviolet rays.

[0014] The curable composition is a composition that cures upon irradiation with light or heating. The photocurable composition that cures upon irradiation with light contains at least a polymerizable compound and a photoinitiator, and may further contain a non-polymerizable compound or a solvent as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, a polymer component, and the like.

[0015] The imprint material may be applied in a film form on a substrate by a spin coater or a slit coater. Further, the imprint material may be applied on the substrate in the form of droplets or in an island or film form formed by connecting a plurality of droplets by a liquid injection head. The viscosity of the imprint material (viscosity at 25°C) is, for example, 1 mPa·s or more and 100 mPa·s or less.

[0016] For the substrate, glass, ceramics, metal, semiconductor, resin, etc. are used, and a member made of a material different from the substrate may be formed on its surface as necessary. Specifically, the substrate includes a silicon wafer, a compound semiconductor wafer, quartz glass, and the like.

[0017] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system with the direction parallel to the surface on which the substrate is disposed as the XY plane. The directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are defined as the X-direction, Y-direction, and Z-direction, respectively, and the rotations around the X-axis, Y-axis, and Z-axis are defined as θX, θY, and θZ, respectively.

[0018] The imprint apparatus 100 forms a pattern of the imprint material 104 by molding the imprint material 104 on a substrate using a mold 103. As shown in FIG. 1, the imprint apparatus 100 includes a measurement unit 101, an imprint head 102, a curing unit 106, a placement unit 107, a substrate stage 109, a stage base plate 110, and a control unit 112.

[0019] The mold 103 is, for example, a master plate in which a three-dimensional pattern of bumps and depressions corresponding to the circuit pattern of a device is formed, and is also called a mold. The mold 103 is made of a material that can transmit light such as ultraviolet light, for example, quartz. In addition, before placing the imprint material 104 on the substrate 105, an adhesion layer may be provided as needed to improve the adhesion between the imprint material 104 and the substrate 105.

[0020] The curing unit 106 cures the imprint material 104 on the substrate by irradiating it with light through the mold 103. The curing unit 106 includes, for example, a light source such as a mercury lamp that emits light (curing light such as i-lines and g-lines) for curing the imprint material 104, an elliptical mirror that focuses the curing light emitted from the light source, and an optical system for irradiating the imprint material 104 with the curing light. Such an optical system includes lenses and apertures for shaping the curing light. The aperture is used for controlling the field of view to irradiate only the shot area to be imprinted, and for controlling the outer edge of the light to prevent the curing light from irradiating outside the shot area. The curing unit 106 may also further include an optical integrator for uniformly illuminating the mold 103.

[0021] The imprint head 102 includes a positioning mechanism for controlling the position of the mold 103 with respect to six axes, and a transfer mechanism for pressing the mold 103 onto the imprint material 104 on the substrate and for pulling the mold 103 away from the cured imprint material 104 on the substrate. Here, the six axes include the X, Y, and Z axes, as well as rotation around each of those axes.

[0022] The substrate stage 109 holds the substrate 105 and is configured to be movable relative to the stage platen 110. The stage platen 110 is a member for supporting the substrate stage 109 in a movable manner. The substrate stage 109 includes, for example, a positioning mechanism for controlling the position of the substrate 105 in six axes.

[0023] The placement unit 107 places (supplies or applies) the imprint material 104 onto the substrate. In this embodiment, the imprint material 104 is an ultraviolet-curable resin that hardens when irradiated with ultraviolet light. The placement unit 107 includes, for example, a tank for containing the imprint material 104, a plurality of nozzles for discharging the imprint material 104 supplied from the tank via a supply path onto the substrate 105, piezoelectric elements provided in the supply path communicating with each nozzle, and a discharge control unit. The discharge control unit controls the amount (discharge amount) and discharge timing of the imprint material 104 discharged as droplets from one nozzle by adjusting the drive signal given to the piezoelectric elements.

[0024] The measurement unit 101 is configured to have a field of view that can capture the mark areas, including the marks provided on the mold 103 and the substrate 105, respectively. The measurement unit 101 includes, for example, four scopes that detect marks provided at the four corners of the shot area on the mold 103 and the substrate. The measurement unit 101 captures an image of the mark area of ​​the shot area to be imprinted via the mold 103 and acquires an image, and based on this image, measures the relative position (positional misalignment) between the mold-side mark group 108 and the substrate-side mark group 111. The measurement unit 101 may also be configured to have a field of view that can capture the entire shot area on the substrate. The mold-side mark group 108 (first mark group) consists of multiple (types) of marks provided on the mold 103. The substrate-side mark group 111 (second mark group) consists of multiple (types) of marks provided on the substrate 105. The substrate-side mark group 111 is provided for each shot area on the substrate and includes multiple marks provided at different positions within the shot area. In this embodiment, at least one of the mold-side mark group 108 and the substrate-side mark group 111 includes a plurality of marks with different optical properties, i.e., different optical properties.

[0025] The control unit 112 is composed of a computer (information processing device) including a CPU and memory. The control unit 112 comprehensively controls each part of the imprint device 100 according to a program stored in the memory unit to operate the imprint device 100. The control unit 112 controls the imprint process, which involves transferring the pattern of the mold 103 onto the imprint material 104 on the substrate to form the pattern of the imprint material 104 on the substrate.

[0026] The measurement unit 101 will be described in detail with reference to Figure 2. Figure 2 is a schematic diagram showing an example of the configuration of the measurement unit 101. The measurement unit 101 includes, for example, a mirror optical system 201, an illumination unit 202, an imaging unit 203, an imaging optical system 204, and an image processing unit 205. In addition to the mirror optical system 201 and the imaging optical system 204, the measurement unit 101 may further include other optical systems, specifically lenses, apertures, mirrors, etc.

[0027] The illumination unit 202 illuminates the substrate 105 via the imaging optical system 204 and the mold 103. The imaging unit 203 captures an image of the mark regions, including the marks provided on the mold 103 and the substrate 105, via the imaging optical system 204 and the mirror optical system 201. The imaging unit 203 includes an image sensor in which a plurality of pixels are arranged to detect light from each mark of the mold-side mark group 108 and the substrate-side mark group 111. In this embodiment, the imaging unit 203 is composed of an image sensor in which a plurality of pixels are arranged so that the mark region of at least one shot region on the substrate can be captured via the imaging optical system 204. Specifically, the imaging unit 203 can be a CMOS sensor, a CCD sensor, a line sensor, etc. The image processing unit 205 is composed of a computer (information processing device) including a CPU and memory, and processes the image acquired by the imaging unit 203 and calculates the relative position of the mold-side mark group 108 and the substrate-side mark group 111 as a measurement result. The function of the image processing unit 205 may also be provided by the control unit 112.

[0028] In an imprint apparatus 100 having such a configuration, the measurement unit 101 measures the relative position (positional misalignment) between the mold-side mark group 108 and the substrate-side mark group 111, and aligns the mold 103 and the substrate 105 based on this relative position. This alignment of the mold 103 and the substrate 105 is controlled by the control unit 112 as part of the imprint process.

[0029] The configurations of the mold-side mark group 108 and the substrate-side mark group 111 will be described in detail with reference to Figures 3(a) and 3(b).

[0030] Figure 3(a) is a schematic diagram showing an example of the configuration of the mold-side mark group 108. As shown in Figure 3(a), the mold-side mark group 108 includes, for example, a wide-area mold-side mark 301 (first rough inspection mark), a high-precision mold-side X mark 302 (first fine inspection mark), and a high-precision mold-side Y mark 303 (first fine inspection mark).

[0031] The wide-area mold mark 301 is a mark for measuring the positional displacement of the mold 103 with respect to the center of the imaging area (detection area) of the imaging unit 203 over a wide area. The high-precision mold X mark 302 is a mark for measuring the positional displacement in the X direction with respect to the substrate-side mark group 111. The high-precision mold Y mark 303 is a mark for measuring the positional displacement in the Y direction with respect to the substrate-side mark group 111.

[0032] Figure 3(b) is a schematic diagram showing an example of the configuration of the substrate-side mark group 111. As shown in Figure 3(b), the substrate-side mark group 111 includes, for example, a substrate-side wide-area mark 304 (second rough inspection mark), a substrate-side high-precision X mark 305 (second fine inspection mark), and a substrate-side high-precision Y mark 306 (second fine inspection mark).

[0033] The wide-area mark 304 on the substrate side is a mark for measuring the positional displacement of the substrate 105 with respect to the center of the imaging area (detection area) of the imaging unit 203 over a wide area. The high-precision X mark 305 on the substrate side is used in combination with the high-precision X mark 302 on the mold side to measure the positional displacement in the X direction with respect to the mold side mark group 108. The high-precision Y mark 306 on the substrate side is used in combination with the high-precision Y mark 303 on the mold side to measure the positional displacement in the Y direction with respect to the mold side mark group 108.

[0034] The alignment of the mold 103 and the substrate 105 will be described below. Figure 4(a) is a schematic diagram showing an example of an image acquired by the imaging unit 203 during the alignment of the mold 103 and the substrate 105, i.e., an overlaid image 401 (mark image) of each mark group provided on the mold 103 and the substrate 105. Referring to Figure 4(a), the overlaid image 401 includes a wide-area mark image 402 on the mold side, a wide-area mark image 403 on the substrate side, a high-precision X-mark overlaid image 404, and a high-precision Y-mark overlaid image 405.

[0035] The wide-area mark image 402 on the mold side is an image of the wide-area mark 301 on the mold side acquired by the imaging unit 203. Specifically, first, light from the illumination unit 202 (illumination light) is shone onto the wide-area mark 301 on the mold side via the imaging optical system 204. Then, the light reflected from the wide-area mark 301 (reflected light) is detected by the imaging unit 203 via the imaging optical system 204 and the mirror optical system 201, thereby acquiring the wide-area mark image 402 on the mold side.

[0036] The wide-area mark image 403 on the substrate side is an image of the wide-area mark 304 on the substrate side acquired by the imaging unit 203. Specifically, first, light from the illumination unit 202 (illumination light) is shone onto the wide-area mark 304 on the substrate side via the imaging optical system 204, the mold 103, and the imprint material 104. Then, the light reflected from the wide-area mark 304 on the substrate side (reflected light) is detected by the imaging unit 203 via the imprint material 104, the mold 103, the imaging optical system 204, and the mirror optical system 201, thereby acquiring the wide-area mark image 403 on the substrate side.

[0037] The high-precision X-mark superimposed image 404 is formed by superimposing (combining) the mold-side high-precision X-mark 302 and the substrate-side high-precision X-mark 305, and is acquired by the imaging unit 203. In this embodiment, the high-precision X-mark superimposed image 404 is an interference fringe image (interference fringe image) formed by the difference between the mark spacing of the mold-side high-precision X-mark 302 and the mark spacing of the substrate-side high-precision X-mark 305.

[0038] The high-precision Y-mark superimposed image 405 is formed by superimposing (combining) the mold-side high-precision Y-mark 303 and the substrate-side high-precision Y-mark 306, and is acquired by the imaging unit 203. In this embodiment, the high-precision Y-mark superimposed image 405 is an interference fringe image (interference fringe image) formed by the difference between the mark spacing of the mold-side high-precision Y-mark 303 and the mark spacing of the substrate-side high-precision Y-mark 306.

[0039] Each of the wide-area mark image 402 on the mold side, the wide-area mark image 403 on the substrate side, the high-precision X-mark superimposed image 404, and the high-precision Y-mark superimposed image 405 is processed by the image processing unit 205 in order to calculate their respective positions (measured values).

[0040] One processing method for the mold-side wide-area mark image 402 and the substrate-side wide-area mark image 403 in the image processing unit 205 is to detect the peak position of the image including the mold-side wide-area mark image 402 and the substrate-side wide-area mark image 403. One processing method for the high-precision X-mark superimposed image 404 and the high-precision Y-mark superimposed image 405 in the image processing unit 205 is to fit the interference fringe image with trigonometric functions or the like.

[0041] In these processing methods, in order to accurately calculate measurement values ​​from the mold-side wide-area mark image 402, the substrate-side wide-area mark image 403, the high-precision X-mark superimposed image 404, and the high-precision Y-mark superimposed image 405, it is necessary that there is no saturation in each image (light intensity). Image saturation includes "overexposure" caused by an excessive amount of light (light intensity) detected by the imaging unit 203 (above the detection limit), and "underexposure" caused by an insufficient amount of light (light intensity) detected by the imaging unit 203 (below the detection limit).

[0042] If the optical properties of the imprint material 104, which is filled between the mold-side mark group 108 (mold 103) and the substrate-side mark group 111 (substrate 105), are similar to those of the mold 103, for example, if their refractive indices are close, sufficient reflected light cannot be obtained from the mold-side mark group 108. In such cases, the mold-side mark group 108 is processed to reflect light, for example, by adding a metal film. In addition, the surface of the substrate 105 may be coated with a planarization film to flatten the surface, an adhesion film to improve adhesion with the imprint material 104, or a protective film necessary when processing the pattern of the imprint material 104. Therefore, the wide-area mark image 402 on the mold side, the wide-area mark image 403 on the substrate side, the high-precision X-mark superimposed image 404, and the high-precision Y-mark superimposed image 405 are each acquired by the imaging unit 203 via different paths. As a result, the amount of light detected by the imaging unit 203 will differ for each image depending on the wavelength of the illumination light, the thickness of the imprint material 104, the type and thickness of the metal film added to the mold-side mark group 108, and the type (optical properties) and thickness of the film added to the surface of the substrate 105.

[0043] Figure 4(b) is a schematic diagram showing an example of an image acquired by the imaging unit 203 during alignment of the mold 103 and the substrate 105, i.e., a superimposed image 406 (mark image) of each mark group provided on the mold 103 and the substrate 105. Referring to Figure 4(b), each image in the superimposed image 406 is saturated. Specifically, the superimposed image 406 includes a wide-area mark image 407 on the mold side that is "overexposed" and a wide-area mark image 408 on the substrate side that is "underexposed". Furthermore, the superimposed image 406 includes a high-precision X-mark superimposed image 409 that is "overexposed" and a high-precision Y-mark superimposed image 410 that is "underexposed". Note that the saturation of each image included in the superimposed image 406, i.e., the combination of "overexposed" and "underexposed", is arbitrary and is not limited to the combination shown in Figure 4(b). These images are acquired by the same imaging unit 203 (measurement unit 101). Therefore, the imaging conditions of the imaging unit 203, such as the range of light intensity detectable by the imaging unit 203 (upper and lower limits of the detection limit), are adjusted for the entire superimposed image 406 in which each image is saturated. In this case, as shown in Figure 4(b), the imaging unit 203 cannot acquire each image included in the superimposed image 406 with the optimal amount of light.

[0044] The specific configuration of the imaging unit 203 will be described with reference to Figures 5A, 5B, 5C, 5D, and 5E.

[0045] Figure 5A is a schematic diagram showing an example of the basic configuration of the imaging unit 203. As shown in Figure 5A, the imaging unit 203 includes a plurality of pixels 501 arranged in a grid, a pixel control unit 502, and a signal processing unit 503. Each pixel 501 has the function of detecting (receiving) light from each mark of the mold-side mark group 108 and the substrate-side mark group 111, and includes, for example, a photodiode, transistor switch, microlens, wavelength filter, ND filter, etc. The pixel control unit 502 has the function of controlling the pixels 501 and controls the imaging conditions (imaging conditions in the image sensor) by the imaging unit 203, such as sensitivity, storage time (exposure time), gain, etc. Here, sensitivity is the sensitivity of the pixel 501 to detect (receive) light from each mark of the mold-side mark group 108 and the substrate-side mark group 111 (such as the range of light amount that can be detected by the pixel 501). Storage time is the time it takes for the pixel 501 to store light from each mark of the mold-side mark group 108 and the substrate-side mark group 111. Gain refers to the gain obtained when converting the light from each mark in the mold-side mark group 108 and the substrate-side mark group 111 detected by the pixel 501 into a detection signal (electrical signal). Note that the function of the pixel control unit 502 may also be provided by the control unit 112. The signal processing unit 503 has a function of processing the detection signal and includes, for example, an AD converter and a signal amplifier.

[0046] In the imaging unit 203 shown in Figure 5A, there is only one pixel control unit 502 that controls all of the multiple pixels 501. Therefore, the imaging conditions are adjusted for all of the multiple pixels 501. In other words, it is not possible to adjust the imaging conditions individually for each of the multiple pixels 501. In this case, as explained with reference to Figure 4(b), it is not possible to acquire each image included in the superimposed image 406 with the optimal amount of light.

[0047] Therefore, in this embodiment, the imaging unit 203 (measurement unit 101) is configured to allow adjustment of imaging conditions for each region containing the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406. Specifically, as shown in Figures 5B to 5E, the imaging conditions can be adjusted by providing a pixel control unit 502 for each of a few pixels 501 among a plurality of pixels 501, or for each of the plurality of pixels 501. The images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 include, as described above, a wide-area mold-side mark image 402, a wide-area substrate-side mark image 403, a high-precision X-mark superimposed image 404, and a high-precision Y-mark superimposed image 405.

[0048] Figure 5B is a schematic diagram showing an example of the configuration of the imaging unit 203 in this embodiment. The imaging unit 203 shown in Figure 5B is constructed by miniaturizing the imaging unit 203 shown in Figure 5A and arranging them in a grid. In other words, a pixel control unit 502 is provided for every few pixels 501 out of a plurality of pixels 501, and in this embodiment, for every four adjacent pixels 501. Therefore, in the imaging unit 203 shown in Figure 5B, the imaging conditions can be adjusted for each region containing four (a few) adjacent pixels 501 (i.e., the imaging conditions can be controlled independently for each unit of four adjacent pixels 501).

[0049] Figure 5C is a schematic diagram showing an example of the configuration of the imaging unit 203 in this embodiment. The imaging unit 203 shown in Figure 5C is configured by dividing each of the multiple pixels 501 into multiple groups, and providing a pixel control unit 502 and a signal processing unit 503 for each group. In this embodiment, each of the multiple pixels 501 is divided into four groups (A, B, C, D) each containing six pixels 501 spaced apart from each other, and a pixel control unit 502 (and signal processing unit 503) is provided for each group. Therefore, in the imaging unit 203 shown in Figure 5C, the imaging conditions can be adjusted for each group containing six (a small number) pixels 501 spaced apart from each other (that is, the imaging conditions can be controlled independently for each group as a single unit).

[0050] Figure 5D is a schematic diagram showing an example of the configuration of the imaging unit 203 in this embodiment. The imaging unit 203 shown in Figure 5D is configured by providing a pixel control unit 502 for each of the multiple pixels 501. In other words, a pixel control unit 502 is provided for each individual pixel 501. Therefore, in the imaging unit 203 shown in Figure 5D, the imaging conditions can be adjusted for each individual pixel 501 (i.e., each pixel 501 can be treated as a single unit, and the imaging conditions can be controlled independently).

[0051] Figure 5E is a schematic diagram showing an example of the configuration of the imaging unit 203 in this embodiment. The imaging unit 203 shown in Figure 5E is configured by providing a pixel control unit 502 and a signal processing unit 503 for each of the multiple pixels 501. In other words, a pixel control unit 502 (and signal processing unit 503) is provided for each pixel 501. Therefore, in the imaging unit 203 shown in Figure 5E, the imaging conditions can be adjusted for each pixel 501 (i.e., each pixel 501 can be treated as a single unit and the imaging conditions can be controlled independently).

[0052] Thus, in this embodiment, the imaging unit 203 is configured as shown in Figures 5B to 5E, according to the image (or region including) of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406. Therefore, in this embodiment, the imaging conditions by the imaging unit 203 can be adjusted for each region including the image of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406.

[0053] Figure 6(a) is a schematic diagram showing an example of a region in the imaging unit 203 that is set to include the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406, that is, a region for detecting (imaging) each mark. As shown in Figure 6(a), the imaging unit 203 includes a mold-side wide-area mark region 601, a substrate-side wide-area mark region 602, a high-precision X-mark region 603, a high-precision Y-mark region 604, and an off-mark region 605 as regions for detecting each mark. The mold-side wide-area mark region 601 is a region for detecting the mold-side wide-area mark 301 (mold-side wide-area mark image 402) of the mold-side mark group 108. The substrate-side wide-area mark region 602 is a region for detecting the substrate-side wide-area mark 304 (substrate-side wide-area mark image 403) of the substrate-side mark group 111. The high-precision X-mark area 603 is the area for detecting the mold-side high-precision X-mark 302 of the mold-side mark group 108 and the substrate-side high-precision X-mark 305 (high-precision X-overlay image 404) of the substrate-side mark group 111. The high-precision Y-mark area 604 is the area for detecting the mold-side high-precision Y-mark 303 of the mold-side mark group 108 and the substrate-side high-precision Y-mark 306 (high-precision Y-overlay image 405) of the substrate-side mark group 111. The non-mark area 605 is the area where no marks exist in the mold-side mark group 108 and the substrate-side mark group 111. These areas are basically set by the pixel control unit 502 or control unit 112 based on the design information (design dimensions) of each mark in the mold-side mark group 108 and the substrate-side mark group 111.

[0054] Figure 6(b) is a schematic diagram showing the superimposed region 601 to 605 set in the imaging unit 203 shown in Figure 6(a) onto the superimposed image 401 shown in Figure 4(a). As shown in Figure 6(b), each region 601 to 604 of the imaging unit 203 is set to include the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406. Therefore, in this embodiment, it is possible to adjust the imaging conditions for each region 601 to 604 of the imaging unit 203, that is, for each region that includes the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406.

[0055] Therefore, in this embodiment, for each region containing the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406, at least one of the imaging conditions by the imaging unit 203, namely sensitivity, storage time, and gain, is adjusted so that such images do not become saturated. Specifically, for each region containing the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406, the imaging conditions by the imaging unit 203 are adjusted so that a peak appears in the waveform obtained from the image of each mark. For example, when adjusting the sensitivity as an imaging condition by the imaging unit 203, the sensitivity is lowered for regions containing overexposed mark images and increased for regions containing underexposed mark images. This makes it possible to acquire each image included in the superimposed image 406 with the optimal amount of light and to determine (measure) the position of the mark corresponding to each image with high precision.

[0056] In this embodiment, the measurement unit 101 (imaging unit 203) configured in this way measures the relative position between the mold-side mark group 108 (mold 103) and the substrate-side mark group 111 (substrate 105), and aligns the mold 103 and the substrate 105 based on this relative position.

[0057] Specifically, first, the mold-side mark group 108 and the substrate-side mark group 111, which are located within one field of view of the imaging unit 203 (image sensor), are simultaneously imaged by the imaging unit 203 to obtain a superimposed image 401. This simultaneously yields a wide-area mold-side mark image 402, a wide-area substrate-side mark image 403, a high-precision X superimposed image 404 (interference fringes), and a high-precision Y superimposed image 405 (interference fringes).

[0058] Next, the positions of the respective imaging units 203 (image sensors) of the mold-side wide-area mark image 402 and the substrate-side wide-area mark image 403 with respect to their imaging areas are determined, and the positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 is determined. At the same time, the high-precision positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 is determined from the high-precision X-overlay image 404 and the high-precision Y-overlay image 405.

[0059] In this embodiment, since the high-precision X superimposed image 404 and the high-precision Y superimposed image 405 are interference fringes, in principle, it is not possible to measure positional deviations larger than the period of these interference fringes. In other words, a high-precision positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 can be obtained when the positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 obtained from the mold-side wide-area mark image 402 and the substrate-side wide-area mark image 403 is less than or equal to the period of the interference fringes. Therefore, the resolution of the mold-side wide-area mark 301 and the substrate-side wide-area mark 304 must be less than or equal to the period of the interference fringes generated by the superimposition (combination) of the high-precision marks on the mold side and the high-precision marks on the substrate side. The high-precision marks on the mold side are the mold-side high-precision X mark 302 and the mold-side high-precision Y mark 303, and the high-precision marks on the substrate side are the substrate-side high-precision X mark 305 and the substrate-side high-precision Y mark 306. The positional relationship obtained from such high-precision marks is the sum of the measured value of the high-precision mark and the product of the integer value of the quotient between the period of the wide-range mark and the period of the interference fringes, and the period of the interference fringes.

[0060] In this embodiment, the positional relationship between the shot area and the mold 103 (pattern) is determined from the positional relationship between the substrate-side mark group 111 provided in the shot area on the substrate and the corresponding mold-side mark group 108, and from the design position of the substrate-side mark group 111 within the shot area. The positional relationship between the shot area on the substrate and the mold 103 (the positional relationship between the mold 103 and the substrate 105) includes, for example, X translation, Y translation, rotation, X magnification, Y magnification, and rhombus shape. Of the positional relationship between the shot area on the substrate and the mold 103, the X translation, Y translation, and rotation are reflected in the drive command values ​​of the substrate stage 109, and the substrate stage 109 is driven to reduce alignment errors. In addition, the X magnification, Y magnification, and rhombus shape are reflected in the drive command values ​​of the magnification / shape correction mechanism, and the magnification / shape correction mechanism is driven to reduce alignment errors. The magnification and shape correction mechanism can be implemented, for example, as a mechanism that deforms the mold 103 (pattern) by applying force to the side of the mold 103, or as a mechanism that deforms the substrate 105 (shot area) by applying heat to the substrate 105. The positional relationship between the shot area on the substrate and the mold 103, and the method for correcting it, are not limited. In this way, the mold 103 and the substrate 105 are aligned by simultaneously imaging the mold-side mark group 108 and the substrate-side mark group 111 to obtain a superimposed image 401 and repeating the alignment operation while determining the positional relationship between the mold 103 and the substrate 105.

[0061] The settings for the regions containing the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406 (mold-side wide-area mark region 601, substrate-side wide-area mark region 602, high-precision X-mark region 603, and high-precision Y-mark region 604) will be described below. The regions containing the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406 are set, for example, by the pixel control unit 502, and as described above, are basically set based on the design information of each mark.

[0062] However, as shown in Figure 7(a), there may be cases where the position of the substrate-side mark group 111 is misaligned with the imaging area (field of view) of the imaging unit 203. In this case, even if the region containing the image of each mark is set based on the design information of each mark in the mold-side mark group 108 and the substrate-side mark group 111, it may not be possible to detect the substrate-side wide-area mark 304 in the substrate-side wide-area mark region 602, for example. Therefore, as shown in Figure 7(b), the region containing the image of each mark may be set based on the position of the image of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406 (mark image) acquired by the imaging unit 203. In other words, the region for detecting each mark in the imaging unit 203 (image sensor) may be set so that the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 are included in the superimposed image 406. Figure 7(a) is a schematic diagram showing an example of a superimposed image 401 acquired by the imaging unit 203, and Figure 7(b) is a schematic diagram showing the state in which each region 601 to 605 set in the imaging unit 203 is superimposed on the superimposed image 401 shown in Figure 7(a).

[0063] Furthermore, during the alignment of the mold 103 and the substrate 105, the positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 changes dynamically as the alignment operation is repeated. Therefore, during the period in which the mold 103 and the substrate 105 are aligned, it is preferable to dynamically set the region containing the image of each mark based on the position of the image of each mark in the mold-side mark group 108 and the substrate-side mark group 111 in the superimposed image 406 acquired by the imaging unit 203.

[0064] Furthermore, when aligning the mold 103 and the substrate 105, the positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 may be significantly misaligned. In this case, it is assumed that the superimposed image 406 acquired by the imaging unit 203 will not include images of each mark in the mold-side mark group 108 and the substrate-side mark group 111. Consequently, each mark cannot be detected in the regions set based on the design information of each mark in the mold-side mark group 108 and the substrate-side mark group 111. In such cases, the imaging unit 203 releases the setting of regions for detecting each mark, adjusts the imaging conditions to be the same across the entire imaging area of ​​the imaging unit 203, and acquires the superimposed image 406. Then, the imaging unit 203 searches for images of each mark in the superimposed image 406 and newly sets regions for detecting each mark in the imaging unit 203 so that the images of each mark detected by the search are included.

[0065] In this embodiment, the adjustment of imaging conditions to be the same across the entire imaging area of ​​the imaging unit 203 was explained using the example of a case where the positional relationship between the mold-side mark group 108 and the substrate-side mark group 111 is significantly misaligned. However, adjusting the imaging conditions to be the same across the entire imaging area of ​​the imaging unit 203 is also useful when the imaging conditions for the areas for detecting the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 are not properly adjusted. For example, if the sensitivity in each area is not appropriate, it becomes possible to search for the images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 by making the sensitivity uniform across the entire imaging area.

[0066] Thus, in this embodiment, the imprint apparatus 100 can acquire images of each mark in the mold-side mark group 108 and the substrate-side mark group 111 with an optimal amount of light, and accurately determine (measure) the position of the mark corresponding to each image. Therefore, according to this embodiment, it is possible to provide a technology that is advantageous for aligning the mold 103 and the substrate 105.

[0067] The cured pattern formed using the imprint apparatus 100 in this embodiment is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. Articles include electrical circuit elements, optical elements, MEMS, recording elements, sensors, or molds. Examples of electrical circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, as well as semiconductor elements such as LSI, CCD, image sensors, and FPGAs. Examples of molds include molds for imprinting.

[0068] The pattern of the cured material is either used as is as a component of at least some of the articles described above, or temporarily used as a resist mask. After etching or ion implantation is performed during the substrate processing process, the resist mask is removed.

[0069] Next, we will explain the specific manufacturing method of the product. As shown in Figure 8(a), a substrate such as a silicon wafer with a workpiece material such as an insulator formed on its surface is prepared, and then an imprint material is applied to the surface of the workpiece material by an inkjet method or the like. Here, we show how multiple droplet-shaped imprint materials are applied to the substrate.

[0070] As shown in Figure 8(b), the mold for imprinting is positioned so that the side with the raised and recessed pattern faces the imprint material on the substrate. As shown in Figure 8(c), the substrate to which the imprint material has been applied and the mold are brought into contact, and pressure is applied. The imprint material fills the gap between the mold and the workpiece. In this state, when light is shone through the mold as curing energy, the imprint material hardens.

[0071] As shown in Figure 8(d), after the imprint material has hardened, when the mold and substrate are separated, a pattern of the hardened imprint material is formed on the substrate. In this pattern, the recesses of the mold correspond to the protrusions of the hardened material, and the protrusions of the mold correspond to the recesses of the hardened material. In other words, the pattern of the mold's irregularities has been transferred to the imprint material.

[0072] As shown in Figure 8(e), when etching is performed using the cured material pattern as an etching-resistant mask, the parts of the workpiece surface where there is no cured material, or where a thin layer remains, are removed, forming grooves. As shown in Figure 8(f), when the cured material pattern is removed, an article with grooves formed on the surface of the workpiece can be obtained. Here, the cured material pattern was removed, but it may also be used without removal after processing, for example, as an interlayer insulating film included in semiconductor devices, i.e., as a component of the article.

[0073] In this embodiment, an imprint apparatus was described as an example of a lithography apparatus that forms a pattern on a substrate using a master plate. However, the lithography apparatus is not limited to an imprint apparatus; it may also be an exposure apparatus that projects a pattern from a master plate (mask or reticle) onto a substrate to expose the substrate.

[0074] The disclosures herein include the following lithography apparatus, lithography methods, and methods for manufacturing articles.

[0075] (Item 1) A lithography apparatus for forming a pattern on a curable composition on a substrate using a master plate, A measuring unit that simultaneously images a first group of marks provided on the original plate and a second group of marks provided on the substrate, both located within a single field of view, to acquire a mark image, and measures the relative position between the first group of marks and the second group of marks, A control unit that measures the relative position using the measurement unit and aligns the original plate and the substrate based on the relative position, It has, The control unit adjusts the imaging conditions for each region including the image of each mark in the first mark group and the second mark group. A lithography apparatus characterized by the following features.

[0076] (Item 2) The aforementioned first group of marks includes a first rough inspection mark and a first detailed inspection mark, The second group of marks includes a second rough inspection mark and a second fine inspection mark that is combined with the first fine inspection mark. The control unit controls the measurement unit to simultaneously capture images of the combination of the first coarse mark, the second coarse mark, the first fine mark, and the second fine mark. A lithography apparatus as described in item 1, characterized by the features described herein.

[0077] (Item 3) The lithography apparatus according to item 2, characterized in that the resolution of the first coarse mark and the second coarse mark, respectively, is less than or equal to the period of the interference fringes produced by the combination of the first coarse mark and the second coarse mark.

[0078] (Item 4) The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group. The imaging conditions include the sensitivity with which each of the plurality of pixels detects the light. A lithography apparatus according to any one of items 1 to 3, characterized by the above.

[0079] (Item 5) The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group. The imaging conditions include an accumulation time during which each of the plurality of pixels accumulates the light. A lithography apparatus according to any one of items 1 to 4, characterized by the above.

[0080] (Item 6) The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group. The imaging conditions include the gain used when converting the light detected by each of the plurality of pixels into an electrical signal. A lithography apparatus according to any one of items 1 to 5, characterized by the above.

[0081] (Item 7) The lithography apparatus according to any one of items 1 to 6, characterized in that the control unit sets the area based on the design information of each mark in the first mark group and the second mark group.

[0082] (Item 8) The lithography apparatus according to any one of items 1 to 7, characterized in that the control unit sets the region based on the position of the images of each mark in the first group of marks and the second group of marks in the mark image acquired by the measuring unit.

[0083] (Item 9) The lithography apparatus according to any one of items 1 to 8, characterized in that the control unit dynamically sets the region based on the position of the images of each mark in the first mark group and the second mark group in the mark image acquired by the measurement unit during the period in which the original plate and the substrate are aligned.

[0084] (Item 10) The lithography apparatus according to any one of items 1 to 9, characterized in that the control unit adjusts the imaging conditions to the same conditions over the entire imaging area for imaging the first mark group and the second mark group when the images of each mark in the first mark group and the second mark group are not included in the mark image.

[0085] (Item 11) A lithography apparatus according to any one of items 1 to 10, characterized in that at least one of the first group of marks and the second group of marks includes a plurality of marks with different optical properties.

[0086] (Item 12) The lithography apparatus according to any one of items 1 to 11, characterized in that the control unit adjusts the imaging conditions for each region such that a peak appears in the waveform obtained from the images of each mark in the first mark group and the second mark group.

[0087] (Item 13) A lithography apparatus according to any one of items 1 to 12, characterized in that it brings the original plate and the curable composition into contact to form a pattern of the curable composition on which the pattern of the original plate has been transferred.

[0088] (Item 14) A lithography method for forming a pattern on a curable composition on a substrate using a master plate, A step of simultaneously imaging a first group of marks provided on the master plate and a second group of marks provided on the substrate, both located within a single field of view, to acquire a mark image, measuring the relative positions of the first group of marks and the second group of marks, and aligning the master plate and the substrate based on those relative positions, A step of adjusting the imaging conditions for each region containing the image of each mark in the first mark group and the second mark group, A lithography method characterized by having [a certain feature].

[0089] (Item 15) A step of forming a pattern on a substrate using a lithography apparatus described in any one of items 1 to 13, A step of processing the substrate on which the pattern has been formed in the above step, A process for manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by having the following:

[0090] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of symbols]

[0091] 100: Imprint device 101: Measurement unit 103: Mold 105: Substrate 108: Mold-side mark group 111: Substrate-side mark group 112: Control unit 203: Imaging unit

Claims

1. A lithography apparatus for forming a pattern on a curable composition on a substrate using a master plate, A measuring unit that simultaneously images a first group of marks provided on the original plate and a second group of marks provided on the substrate, both located within a single field of view, to acquire a mark image, and measures the relative position between the first group of marks and the second group of marks, A control unit that measures the relative position using the measurement unit and aligns the original plate and the substrate based on the relative position, It has, The control unit adjusts the imaging conditions for each region including the image of each mark in the first mark group and the second mark group. A lithography apparatus characterized by the following features.

2. The aforementioned first group of marks includes a first rough inspection mark and a first detailed inspection mark, The second group of marks includes a second rough inspection mark and a second fine inspection mark that is combined with the first fine inspection mark. The control unit controls the measurement unit to simultaneously capture images of the combination of the first coarse mark, the second coarse mark, the first fine mark, and the second fine mark. The lithography apparatus according to feature 1.

3. The lithography apparatus according to claim 2, characterized in that the resolution of the first coarse mark and the second coarse mark, respectively, is less than or equal to the period of the interference fringes generated by the combination of the first coarse mark and the second coarse mark.

4. The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group, The imaging conditions include the sensitivity with which each of the plurality of pixels detects the light. The lithography apparatus according to feature 1.

5. The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group, The imaging conditions include an accumulation time during which each of the plurality of pixels accumulates the light. The lithography apparatus according to feature 1.

6. The measurement unit includes a plurality of pixels that detect light from each mark in the first mark group and the second mark group, The imaging conditions include the gain used when converting the light detected by each of the plurality of pixels into an electrical signal. The lithography apparatus according to feature 1.

7. The lithography apparatus according to claim 1, characterized in that the control unit sets the area based on the design information of each mark in the first mark group and the second mark group.

8. The lithography apparatus according to claim 1, characterized in that the control unit sets the region based on the position of the images of each mark in the first mark group and the second mark group in the mark image acquired by the measurement unit.

9. The lithography apparatus according to claim 1, characterized in that the control unit dynamically sets the region based on the position of the images of each mark in the first mark group and the second mark group in the mark image acquired by the measurement unit during the period in which the original plate and the substrate are aligned.

10. The lithography apparatus according to claim 1, characterized in that the control unit adjusts the imaging conditions to be the same across the entire imaging area for imaging the first mark group and the second mark group when the images of each mark in the first mark group and the second mark group are not included in the mark image.

11. The lithography apparatus according to claim 1, characterized in that at least one of the first group of marks and the second group of marks includes a plurality of marks with different optical properties.

12. The lithography apparatus according to claim 1, characterized in that the control unit adjusts the imaging conditions for each region such that a peak appears in the waveform obtained from the images of each mark in the first mark group and the second mark group.

13. The lithography apparatus according to claim 1, characterized in that the original plate and the curable composition are brought into contact to form a pattern of the curable composition on which the pattern of the original plate has been transferred.

14. A lithography method for forming a pattern on a curable composition on a substrate using a master plate, A step of simultaneously imaging a first group of marks provided on the master plate and a second group of marks provided on the substrate, both located within a single field of view, to acquire a mark image, measuring the relative positions of the first group of marks and the second group of marks, and aligning the master plate and the substrate based on those relative positions, A step of adjusting the imaging conditions for each region containing the image of each mark in the first mark group and the second mark group, A lithography method characterized by having [a certain feature].

15. A step of forming a pattern on a substrate using the lithography apparatus described in claim 1, A step of processing the substrate on which the pattern has been formed in the above step, A process for manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by having the following:

Images