JP7701883B2 - Imprinting apparatus, imprinting method and article manufacturing method - Google Patents

Description

The present invention relates to an imprinting apparatus, an imprinting method, and an article manufacturing method.

Imprinting apparatuses can be used in lithography processes for manufacturing articles such as magnetic storage media and semiconductor devices. In the imprinting apparatus, a mold is brought into contact with an imprinting material placed on a shot area of a substrate, and the imprinting material is cured, thereby transferring the pattern of the mold onto the shot area of the substrate. For example, in the manufacture of semiconductor devices, the accuracy (alignment accuracy) of overlaying a new circuit pattern to be formed on a circuit pattern already formed on the substrate is important. In the imprinting apparatus, a die-by-die alignment method is adopted as an alignment method between the shot area of the substrate and the mold. The die-by-die alignment method is a method of optically detecting the relative positions of a substrate-side mark and a mold-side mark for each shot area of the substrate to align the shot area and the mold.

Patent document 1 describes a method of correcting the relative position between the second shot area and the mold before contacting the imprint material on the second shot area with the mold, based on the amount of misalignment between the first shot area and the mold when imprint processing is performed on the first shot area.

JP 2016-76626 A

In die-by-die alignment, the shot area and the mold are aligned by using a detector to detect the relative positions of a mark provided in the shot area of the substrate and a mark provided on the mold. Here, the effects of aberrations in the detector's optical system and uneven illuminance of the mark can vary depending on the position within the detector's field of view, so the detection error by the detector can vary depending on the position of the mark within the detector's field of view.

The present invention aims to provide an advantageous technology for improving the alignment accuracy between the shot area of a substrate and a mold.

One aspect of the present invention relates to an imprinting apparatus that performs an imprinting process on a plurality of shot areas of a substrate, in which a pattern of a mold is transferred to an imprinting material arranged on the substrate, the imprinting apparatus comprising: a detector for detecting a first mark provided on the substrate and a second mark provided on the mold; and a control unit that controls positioning of the detector based on a first driving amount by which the detector should be driven in order to place the first mark and the second mark within a specific area of a field of view of the detector, and a second driving amount based on a correction value that corrects the first driving amount, the first driving amount and the correction value being stored in a memory unit, the control unit drives the detector based on the second driving amount, aligns a shot area selected from the plurality of shot areas with the mold based on an output of the detector, and updates the correction value stored in the memory unit based on the output of the detector when the alignment is performed.

The present invention provides an advantageous technique for improving the alignment accuracy between the shot area of the substrate and the mold.

FIG. 1 is a diagram illustrating a schematic and exemplary configuration of an imprint apparatus according to an embodiment. FIG. 4 is a diagram for explaining detection of a mark by a detector (scope). FIG. 2 is a diagram showing a schematic diagram of the operation of a detector (scope). FIG. 4 is a diagram illustrating an example of the arrangement of a plurality of marks. FIG. 2 is a diagram showing a schematic diagram of the operation of a detector (scope). 1 is a diagram illustrating an example of the operation of an imprint apparatus; 1 is a diagram illustrating an example of the operation of an imprint apparatus; 1 is a diagram illustrating a method for manufacturing an article.

The following embodiments are described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe multiple features, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicate explanations are omitted.

In this specification and the accompanying drawings, directions are shown in an XYZ coordinate system in which the direction parallel to the surface of the substrate is the XY plane. The directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are the X-direction, Y-direction, and Z-direction, respectively, and rotation around the X-axis, rotation around the Y-axis, and rotation around the Z-axis are θX, θY, and θZ, respectively. Control or drive regarding the X-axis, Y-axis, and Z-axis means control or drive regarding the direction parallel to the X-axis, direction parallel to the Y-axis, and direction parallel to the Z-axis, respectively. In addition, control or drive regarding the θX-axis, θY-axis, and θZ-axis means control or drive regarding the rotation around an axis parallel to the X-axis, rotation around an axis parallel to the Y-axis, and rotation around an axis parallel to the Z-axis, respectively. In addition, position is information that can be specified based on the coordinates of the X-axis, Y-axis, and Z-axis, and orientation is information that can be specified by the values of the θX-axis, θY-axis, and θZ-axis. Positioning means controlling the position and/or orientation. Alignment may include controlling the position and/or attitude of at least one of the substrate and the mold so that an alignment error (overlay error) between the shot area of the substrate and the (pattern area of the) mold is reduced. Alignment may also include control for correcting or changing the shape of at least one of the shot area of the substrate and the pattern area of the mold.

In FIG. 1, the configuration of an imprinting apparatus NIL according to an embodiment is shown in a schematic and exemplary manner. The imprinting apparatus NIL can be configured to perform an imprinting process for transferring a pattern of a mold 11 to an imprinting material arranged on the substrate 1, for a plurality of shot areas of the substrate 1. As the imprinting material, a curable composition (sometimes called an uncured resin) that is cured by applying curing energy is used. As the curing energy, electromagnetic waves, heat, and the like can be used. The electromagnetic waves can be, for example, light having a wavelength selected from the range of 10 nm or more and 1 mm or less, such as infrared rays, visible light, and ultraviolet rays. The curable composition can be a composition that is cured by irradiation with light or by heating. Of these, the photocurable composition that is cured by irradiation with light contains at least a polymerizable compound and a photopolymerization initiator, 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, and a polymer component. The imprint material may be arranged on the substrate in the form of droplets, or in the form of islands or a film formed by connecting a plurality of droplets. The imprint material may also be supplied in the form of a film on the substrate by a spin coater or a slit coater. The viscosity of the imprint material (at 25°C) may be, for example, 1 mPa·s or more and 100 mPa·s or less. The substrate may be made of, for example, glass, ceramics, metal, semiconductor (Si, GaN, SiC, etc.), resin, etc. If necessary, a member made of a material different from the substrate may be provided on the surface of the substrate. The substrate may be, for example, a silicon wafer, a compound semiconductor wafer, or quartz glass.

The mold 11 has a pattern area on the surface facing the substrate 1, and the pattern area has a pattern such as a circuit pattern. The pattern may be understood to be composed of recesses that are recessed relative to a reference surface, or may be understood to be composed of protrusions that protrude from the reference surface. The material of the mold 11 is a material such as quartz that can transmit light such as ultraviolet light as the energy for curing.

The imprint apparatus NIL may include a substrate operation mechanism 2, a mold operation mechanism 13, a curing unit 41, one or more detectors (scopes) 14, a dispenser 21, and a control unit 40. The substrate operation mechanism 2 may include a substrate holding unit that holds the substrate 1, and a substrate driving mechanism that positions the substrate 1 by driving the substrate holding unit. The substrate operation mechanism 2 may be configured to drive the substrate 1 about multiple axes (e.g., three axes of the X axis, the Y axis, and the θZ axis, preferably six axes of the X axis, the Y axis, the Z axis, the θX axis, the θY axis, and the θZ axis). The substrate holding unit may hold the substrate 1 by a holding method such as vacuum suction or electrostatic suction. The substrate driving mechanism may drive the substrate holding unit along the base plate 3. The base plate 3 may be supported by a mount 4, which may reduce vibrations transmitted from the floor to the base plate 3.

The mold operation mechanism 13 may include a mold holding part that holds the mold 11, and a mold operation mechanism that positions the mold 11 by driving the mold holding part. The mold operation mechanism 13 may be configured to drive the mold 11 about multiple axes (for example, three axes of the Z axis, the θX axis, and the θY axis, and preferably six axes of the X axis, the Y axis, the Z axis, the θX axis, the θY axis, and the θZ axis). The substrate operation mechanism 2 and the mold operation mechanism 13 constitute a relative drive mechanism that drives at least one of the substrate 1 and the mold 11 so that the relative positions of the substrate 1 and the mold 11 are adjusted. The adjustment of the relative position by the relative drive mechanism includes contact of the mold 11 with the imprint material on the substrate 1, and drive for separation of the mold 11 from the cured imprint material (pattern of the cured product). The adjustment of the relative position by the relative drive mechanism also includes alignment of the substrate 1 (shot area) and the mold 11 (pattern area). The mold operation mechanism 13 may include a deformation mechanism 12 that deforms the mold 11 or the pattern area of the mold 11. The deformation of the mold 11 or the pattern area of the mold 11 by the deformation mechanism 12 can contribute to improving the alignment accuracy between the shot area of the substrate 1 and the pattern area of the mold 11.

The curing unit 41 cures the imprint material placed or filled in the space between the shot area of the substrate 1 and the pattern area of the mold 11 by irradiating the imprint material with curing energy (e.g., light energy). The curing unit 41 may include a mirror 42 that deflects or bends the curing energy. The curing unit 41 may also include one or more other optical elements.

Each detector 14 can be used to detect a mark (conveniently referred to as a first mark) provided on the substrate 1 (in its shot area) and a mark (conveniently referred to as a second mark) provided on the mold 11. For example, the detector 14 can be used to detect the relative position of the first mark provided on the shot area of the substrate 1 and the second mark provided on the mold 11. Alternatively, the detector 14 can be used to detect the position of at least one of the first mark provided on the shot area of the substrate 1 and the second mark provided on the mold 11 (for example, the position within the field of view of the detector 14).

The detector 14 may also be called, for example, an alignment scope. The detector 14 may include an imaging element (e.g., an image sensor such as a CCD sensor or a MOS sensor), an optical system that forms images of the first mark and the second mark on the imaging surface of the imaging element, and an illuminator that irradiates the first mark and the second mark with measurement light 63. The image formed on the imaging surface may be an image formed individually by each of the first mark and the second mark, or may be a moire image or interference fringes formed by the first mark and the second mark when the mold and the substrate are in contact with each other via the imprint material. At least one of the first mark and the second mark may be part of a circuit pattern.

The imprint apparatus NIL may include a plurality of driving mechanisms 70 that individually drive and position the plurality of detectors 14. Each driving mechanism 70 may drive the detector 14 so that the first mark and the second mark that constitute a mark pair fall within a specific region of the field of view of the detector 14. Such an operation may be controlled by the control unit 40. The specific region of the field of view of the detector 14 may be, for example, a central region of the field of view. The central region may be a region that is symmetrical about the center of the field of view and has an area of 50% or less, 40% or less, 30% or less, 20% or less, or 10% or less of the area of the field of view.

The imprinting apparatus NIL may include an optical system such as a relay optical system 64 between the mold 11 or the mold operation mechanism 13 and one or more detectors 14, and at least a part of the optical system may be shared with the curing unit 41, for example. The relay optical system 64 may include, for example, one or more lenses 61 and one or more mirrors 62. The relay optical system 64 may be a unity system or a magnification system. The relay optical system 64 may include, for example, two lenses 61 and two mirrors 62, but is not limited to this. In addition, it is preferable that the relay optical system 64 is a telecentric optical system. In this specification, the detector 14 means a part that is driven and positioned by the drive mechanism 70, and the relay optical system 64 is described as a component different from the detector 14. A configuration including the detector 14 and the relay optical system 64 may be understood as a detection system.

The dispenser 21 is configured to supply or place the imprint material 22 on the shot area of the substrate 1. The dispenser 21 is an optional component, and may not be necessary if the imprint material is placed on the substrate 1 by a dispenser external to the imprint apparatus NIL. The type of imprint material 22 may be appropriately selected depending on the type of article, such as a semiconductor device, to be manufactured. The curing energy (e.g., wavelength) irradiated to the imprint material 22 by the curing unit 41 may also be changed depending on the type of imprint material 22.

The imprinting apparatus NIL may further include an alignment measuring instrument 31 for positioning the substrate 1, and a transport system for transporting the mold 11 and the substrate 1 into and out of a chamber (not shown) of the imprinting apparatus 1. The alignment measuring instrument 31 may detect, for example, misalignment of the substrate 1 in the X and Y directions. The transport system may include a mold transport mechanism (not shown) for transporting the mold 11 in and out, and a substrate transport mechanism for transporting the substrate 1 in and out. The mold transport mechanism has a transport robot and may transport the mold 11 between a mold stocker arranged at a predetermined position and the mold operation mechanism 13. The mold stocker may be a carrier that stores multiple molds 11. The substrate transport mechanism 51 may transport the substrate 1 by the transport robot between a substrate carrier (not shown) that may be arranged at a predetermined substrate entrance and a substrate holder of the substrate operation mechanism 2.

The control unit 40 controls the above components of the imprint device NIL and can define the operation of the imprint device NIL based on information stored in a storage unit MEM such as a memory. The storage unit MEM may be provided inside the control unit 40 or outside the control unit 40. The control unit 40 can be configured, for example, by a PLD (abbreviation for Programmable Logic Device) such as an FPGA (abbreviation for Field Programmable Gate Array), an ASIC (abbreviation for Application Specific Integrated Circuit), a general-purpose or dedicated computer with a built-in program, or a combination of all or part of these.

The operation of the imprint apparatus NIL is described below by way of example. This operation is controlled by the control unit 40. The control unit 40 can control the substrate transport mechanism 51 so that the substrates 1 constituting the lot are transported from the substrate carrier to the substrate holding section of the substrate operation mechanism 2. The control unit 40 can also control the mold transport mechanism so that the mold 11 specified by the control information (processing recipe) that controls the processing for the lot is transported from the mold stocker to the mold holding section of the mold operation mechanism 13.

Next, the control unit 40 may perform pre-alignment measurement to measure the relative positions between the mold 11 and each shot area of the substrate 1. Specifically, the control unit 40 may use the alignment measurement device 31 and the detector 14 to measure the positions of the substrate 1 and the mold 11 based on the coordinates of the imprint apparatus NIL. Here, the control unit 40 may cause the drive mechanism 70 to drive the detector 14 so that a second mark selected from the multiple second marks provided on the mold 11 enters the field of view of the detector 14. Then, as shown in FIG. 2A, the position of the second mark 72 of the mold 11 may be measured or detected based on the position of the detector 14. Meanwhile, the control unit 40 may use the alignment measurement device 31 to measure or detect the positions of each first mark while controlling the substrate operation mechanism 2 so that the multiple first marks provided on the substrate 1 enter the field of view of the alignment measurement device 31 in sequence. As a result, the positions of the multiple shot areas of the substrate 1 may be measured or detected based on the position of the substrate operation mechanism 2.

Next, the control unit 40 may control the substrate operation mechanism 2 and the dispenser 21 so that the imprint material is placed on one of the multiple shot areas of the substrate 1 where the imprint process is to be performed. The control unit 40 may then control the substrate operation mechanism 2 so that the shot area is positioned under the mold 11. Next, the control unit 40 may control the mold operation mechanism 13 so that the imprint material on the shot area comes into contact with the pattern area of the mold 11. This allows the imprint material on the shot area to fill the space between the shot area and the pattern area of the mold 11 (including the pattern of the pattern area). Furthermore, the control unit 40 may cause the multiple drive mechanisms 70 to drive the multiple detectors 14 so that the second mark to be detected is placed within a specific area of the field of view of each of one or more detectors 14, typically the multiple detectors 14.

Next, the control unit 40 can align the shot area of the substrate 1 with the pattern area of the mold 11 based on the detection results from the multiple detectors 14. This type of alignment is called die-by-die alignment. At this time, the control unit 40 may deform the mold 11 or the pattern area using the deformation mechanism 12.

Next, the control unit 40 may control the curing unit 41 so that energy for curing is irradiated to the imprint material on the shot area of the substrate 1 via the mold 11. As a result, the imprint material on the shot area of the substrate 1 is cured, and a pattern made of a cured product of the imprint material may be formed. Next, the control unit 40 may control the mold operating mechanism 13 so that the mold 11 is separated from the cured product of the imprint material on the shot area of the substrate 1. As a result, a cured product pattern to which the pattern of the pattern area of the mold 11 is transferred may remain on the shot area of the substrate 1. The control unit 40 may repeat the above process for the remaining shot areas of the substrate 1, thereby forming a pattern made of a cured product of the imprint material in all shot areas of the substrate 1.

In FIG. 3, four mark pairs MP are shown. Each mark pair MP is composed of a first mark provided in the shot area of the substrate 1 and a second mark provided in the mold 11. With reference to FIG. 3, the driving of the detector 14 by the driving mechanism 70 in the operation of placing the mark pair MP, i.e., the first mark provided in the substrate 1 and the second mark provided in the mold 11, within a specific area of the field of view of the detector 14 will be described. In FIG. 3, the shot area of the substrate 1 and the pattern area of the mold 11 are shown as areas 91. Also, in FIG. 3, a mark pair consisting of the first mark provided in the substrate 1 and the second mark provided in the mold 11 is shown as the mark pair MP. The mark pair MP can be understood as representing the first mark or as representing the second mark.

The mold 11 can be held by the mold holding portion of the mold operation mechanism 13 so that the center of the pattern area of the mold 11 approximately coincides with the origin O (0,0) of the imprint apparatus NIL. In addition, the substrate 1 can be aligned by the substrate operation mechanism 2 so that the center of the shot area that will be immediately imprinted among the multiple shot areas approximately coincides with the origin O (0,0) of the imprint apparatus NIL. As a result, the center of the shot area of the substrate 1 and the center of the pattern area of the mold 11 approximately coincide with the origin O (0,0) of the imprint apparatus NIL.

The relative positions of the multiple mark pairs MP, here the first to fourth mark pairs MP, relative to the center of the shot area of the substrate 1 or the pattern area of the mold 11 are (Δx1, Δy1), (Δx2, Δy2), (Δx3, Δy3), and (Δx4, Δy4). In order to place each mark pair MP within a specific area of the field of view of the corresponding detector 14 among the four detectors 14, the drive amounts when moving the four detectors 14 from their respective home positions are (Mx1, My1), (Mx2, My2), (Mx3, y3), and (Mx4, My4). The drive amounts (Mx1, My1), (Mx2, My2), (Mx3, y3), and (Mx4, My4) are expressed, for example, as in the following formula (1).

(Mx1, My1) = (Δx1, Δy1) - (SPx1, SPy1)
(Mx2, My2) = (Δx2, Δy2) - (SPx2, SPy2)
(Mx3, My3) = (Δx3, Δy3) - (SPx3, SPy3)
(Mx4, My4) = (Δx4, Δy4) - (SPx4, SPy4)
...Formula (1)
Here, (SPx1, SPy1), (SPx2, SPy2), (SPx3, SPy3), SPx3, SPy3), and (SPx4, SPy4) are the coordinates of the home positions of the first to fourth detectors 14, respectively. The control unit 40 can acquire, for example, (Δx1, Δy1), (Δx2, Δy2), (Δx3, Δy3, (Δx4, Δy4) from control information (processing recipe) that controls processing for a lot. Here, when error factors can be ignored, the first to fourth detectors 14 can be driven according to the drive amounts (Mx1, My1), (Mx2, My2), (Mx3, y3), and (Mx4, My4) to place the mark pair MP within a specific region of the field of view. However, in reality, error factors may include aberration of the relay optical system 64, characteristic changes due to heat, and the like, drive errors by the drive mechanism 70, and uneven illuminance of the measurement light 63 of the detector 14. Therefore, it is difficult to place the mark pair MP within a specific region of the field of view simply by driving the first to fourth detectors 14 according to the drive amounts (Mx1, My1), (Mx2, My2), (Mx3, y3), and (Mx4, My4).

As shown diagrammatically in FIGS. 2(a) to (d), the relative position of the mark pair MP (first mark 71 and second mark 72) in the field of view 81 of the detector 14 may change depending on the relative position between the detector 14 and the mark pair MP. When the relative position of the mark pair MP in the field of view 81 changes, the appearance of the mark pair MP (such as the shape of the mark or mark pair in the detection image) may change due to aberration of the relay optical system 64 and uneven illuminance of the measurement light 63. The detection result of the relative position of the first mark 71 and the second mark 72 obtained by image processing the detection image of the mark pair MP by the detector 14 may also change depending on the relative position of the mark pair MP in the field of view 81.

When the mark pair MP and detector 14 are in a relative position as shown in FIG. 2(a), the mark pair MP falls within the central region of the field of view 81 of the detector 14 as shown in FIG. 2(b). On the other hand, when the mark pair MP and detector 14 are in a relative position as shown in FIG. 2(c), the mark pair MP does not fall within the central region of the field of view 81 of the detector 14 as shown in FIG. 2(d). The detection accuracy of the relative positions of the first mark 71 and the second mark 72 differs between FIG. 2(b) and FIG. 2(d), and specifically, FIG. 2(b) has higher detection accuracy.

In alignment by die-by-die alignment, measurement error in the relative position between the first mark 71 provided in the shot area of the substrate 1 and the second mark 72 provided on the mold 11 affects the alignment accuracy. For this reason, it is preferable to detect the relative position between the first mark 71 and the second mark 72 with the mark pair MP always falling within a specific area (preferably the central area) in the field of view 81 of the detector 14, thereby making it possible to limit the measurement error to a constant value.

However, the measurement light 63 used by the detector 14 may generate heat in the optical elements of the relay optical system 64, such as the lens 61 and the mirror 62. This may cause the optical characteristics of the relay optical system 64 to change, and this change in the optical characteristics may result in a change in the relative position of the mark pair MP in the field of view 81 of the detector 14. Furthermore, the relative position of the mark pair MP in the field of view 81 of the detector 14 may also change due to a driving error of the detector 14 by the driving mechanism 70.

As illustrated in FIG. 4, problems may also occur when multiple second marks 72 (in other words, mark pairs MP) in the pattern region 92 of the mold 11 are selectively used to detect alignment errors between the shot region and the pattern region 92. Specifically, the amount of heat possessed by each of the multiple second marks 72 (mark pairs MP) may differ. Therefore, the amount of deviation in the relative position of the mark pairs MP in the field of view 81 of the detector 14 may change depending on the mark pairs MP in the shot region or pattern region 92.

Therefore, in this embodiment, the control unit 40 determines the drive amounts (M'x1, M'y1), (M'x2, M'y2), (M'x3, M'y3), and (M'x4, M'y4) when moving the four detectors 14 from their respective home positions to the target coordinate positions (target positions) according to equation (2) instead of equation (1).

(M'x1, M'y1) = (Mx1, My1) + (Cx1, Cy1)
(M'x2, M'y2) = (Mx2, My2) + (Cx2, Cy2)
(M'x3, M'y3) = (Mx3, My3) + (Cx3, Cy3)
(M'x4, M'y4) = (Mx4, My4) + (Cx4, Cy4)
...Formula (2)
Here, (Mx1, My1) is the drive amount by which the detector 14 should be driven in order to place a first mark pair (first and second marks) selected from the multiple mark pairs used for measuring alignment errors within a specific region of the field of view of the detector 14 that measures the first mark pair. Similarly, (Mx2, My2) is the drive amount by which the detector 14 should be driven in order to place a second mark pair (first and second marks) selected from the multiple mark pairs used for measuring alignment errors within a specific region of the field of view of the detector 14 that measures the second mark pair. Similarly, (Mx3, My3) is the drive amount by which the detector 14 should be driven in order to place a third mark pair (first and second marks) selected from the multiple mark pairs used for measuring alignment errors within a specific region of the field of view of the detector 14 that measures the third mark pair. Similarly, (Mx4, My4) is the amount by which the detector 14 should be driven to bring 42 mark pairs (first and second marks) selected from the multiple mark pairs used to measure the alignment error within a specific region of the field of view of the detector 14 that measures it.

Furthermore, (Cx1, Cy1), (Cx2, Cy2), (Cx3, Cy3), and (Cx4, Cy4) are correction values according to the relative position of the first mark 71 in the shot area (or the second mark 72 in the pattern area). Equation (2) may be transformed into the following equation (3) using equation (1).

(M'x1, M'y1) = (Δx1, Δy1) - (SPx1, SPy1) + (Cx1, Cy1)
(M'x2, M'y2) = (Δx2, Δy2) - (SPx2, SPy2) + (Cx2, Cy2)
(M'x3, M'y3) = (Δx3, Δy3) - (SPx3, SPy3) + (Cx3, Cy3)
(M'x4, M'y4) = (Δx4, Δy4) - (SPx4, SPy4) + (Cx4, Cy4)
...Formula (3)
In Fig. 5, drive amounts (Mx1, My1), (Mx2, My2), (Mx3, y3), and (Mx4, My4) are exemplified as drive amounts M before correction. Also, in Fig. 5, drive amounts (M'x1, M'y1), (M'x2, M'y2), (M'x3, M'y3), and (M'x4, M'y4) are exemplified as drive amounts M' after correction. Also, in Fig. 5, correction values (Cx1, Cy1), (Cx2, Cy2), (Cx3, Cy3), and (Cx4, Cy4) are exemplified as correction values C. Also, the following description will follow this notation method.

Figure 6 shows the flow of processing for forming a pattern on multiple shot areas of a substrate 1 in the imprint apparatus NIL. The processing shown in Figure 6 is controlled by the control unit 40. In step S100, the control unit 40 controls the substrate operation mechanism 2 and the dispenser 21 so that the imprint material is placed on a shot area selected from the multiple shot areas (hereinafter, the selected shot area). In step S101, the control unit 40 controls the substrate operation mechanism 2 so that the selected shot area is positioned under the mold 11 for the imprint processing on the selected shot area from the multiple shot areas.

In step S102, the control unit 40 determines a plurality of drive amounts M' for driving each of the plurality of detectors 14 according to formula (2) or formula (3) based on the drive amount M and the correction amount C stored in the memory unit MEM. Note that M' = M + C. Here, the control unit 40 updates the correction value C stored in the memory unit MEM in step S105 described later. Therefore, when the updated correction value C is stored in the memory unit MEM, the control unit 40 can determine the drive amount M' based on the drive amount M and the updated correction value C. Typically, the plurality of drive amounts M' are different from each other, and the plurality of correction values C are different from each other. In step S103, the control unit 40 controls the plurality of drive mechanisms 70 to drive the plurality of detectors 14 according to the plurality of drive amounts M' determined in step S102. Here, if the plurality of correction values C for determining each of the plurality of drive amounts M' are appropriate, the corresponding mark pairs will fit within a specific area of the field of view of each of the plurality of detectors 14 by this drive. When performing imprint processing on multiple shot areas in succession, the control unit 40 may move the detector 14 to a position determined by the drive amount M' for the next shot area, without returning the detector 14 to the home position. In this case, if the correction value C is the same as when the previous shot area was processed, the position of the detector 14 is also the same as when the previous shot area was processed, so the detector 14 does not need to be moved.

In step S103, the control unit 40 executes the imprint process. The imprint process may include a contact process, an alignment process, a filling process, a curing process, and a separation process. In the contact process, the control unit 40 controls the mold operation mechanism 13 so that the pattern area of the mold 11 comes into contact with the imprint material on the selected shot area. This starts filling the space between the selected shot area and the pattern area with the imprint material. In parallel with filling the imprint material, an alignment process is executed.

In the alignment process, the control unit 40 aligns the selected shot area with the mold based on the output of the multiple detectors 14. Specifically, in the alignment process, the control unit 40 uses the multiple detectors 14 to detect the relative positions of the first and second marks in the multiple mark pairs, and detects the alignment error between the selected shot area and the pattern area of the mold 11 based on the results. In the alignment process, the control unit 40 performs alignment between the selected shot area and the pattern area of the mold 11 while controlling at least one of the substrate operation mechanism 2 and the mold operation mechanism 13 so that the alignment error falls within an allowable range. The detection of the alignment error and the alignment based thereon can be repeated multiple times or performed continuously. In the curing process, the control unit 40 controls the curing unit 41 so that the imprint material between the selected shot area and the pattern area of the mold 11 is irradiated with energy for curing. In the separation process, the control unit 40 controls the mold operation mechanism 13 so that the pattern area of the mold 11 is separated from the cured imprint material on the selected shot area.

In step S105, the control unit 40 may update the correction values (Cx1, Cy1), (Cx2, Cy2), Cx3, Cy3), and Cx4, Cy4) stored in the memory unit MEM based on the output of the detector 14 in the imprint process for the selected shot area. This correction value is, for example, the amount of deviation between the center position of the field of view of the detector 14 during alignment and the representative position of the mark pair. For example, the control unit 40 may update the correction values (Cx1, Cy1), (Cx2, Cy2), Cx3, Cy3), and (Cx4, Cy4) based on the amount and direction of change in the representative position of the mark pair due to the execution of the alignment process. The representative position of the mark pair is, for example, the average position of the center position of the first mark and the center position of the second mark. Alternatively, the control unit 40 may update the correction values (Cx1, Cy1), (Cx2, Cy2), Cx3, Cy3), and (Cx4, Cy4) based on the amount and direction of change in the position of the first mark due to the execution of the alignment process. Alternatively, the control unit 40 may update the correction values (Cx1, Cy1), (Cx2, Cy2), (Cx3, Cy3), and Cx4, Cy4) based on the amount and direction of change in the position of the second mark due to the execution of the alignment process. The correction values (Cx1, Cy1), (Cx2, Cy2), (Cx3, Cy3), and Cx4, Cy4) may be used to perform the alignment process using a mark pair having the same relative position as the relative position of the mark pair in the shot area when updating the correction values. As described above, the correction values may depend on, for example, the aberration of the detector 14 and/or the driving error of the driving mechanism 70 that drives the detector 14.

In step S106, the control unit 40 determines whether imprint processing has been completed for all shot areas on the substrate that are to be imprinted, and if there are any unprocessed shot areas, the process returns to step S100 so that imprint processing can be performed on those shot areas.

Here, there are individual differences between multiple detectors 14, and the heat generated by the measurement light may also differ. Therefore, the correction value C in formula (2) or formula (3) may be managed in a memory unit for each individual detector 14.

7(a) and (b) show schematic diagrams of imprint processing performed on multiple shot areas 101 of a substrate. In addition, in FIG. 7(a) and (b), the positions of the first marks in the shot areas 101 are indicated by the symbols ◯, ×, △, □, ◎, and ☆. Shot areas without △ and □ are so-called partial shot areas, whose shape is restricted by the outer edge of the substrate. When imprint processing is performed in the order shown by the arrows in FIG. 7(a), there are multiple shot areas 101 in which alignment is performed using mark pairs with the same relative positions in the shot area 101. For such multiple shot areas 101, the drive amount M' can be determined using the correction value C updated in the processing of the previous shot area, for example.

Furthermore, the correction value C may be managed using the memory unit MEM for each relative position in the shot area, such as the symbols ◯, ×, △, □, ◎, and ☆. In FIG. 7B, the alignment operation is performed by moving the same detector 14 for □ and ☆, and △ and ◎. However, when the position of the same detector 14 is moved significantly, such as between □ and ☆, the position of the measurement light 63 passing through the relay optical system will change. Therefore, it is preferable to manage the correction values as separate correction values for each relative position in the shot area. In other words, the correction value for ☆ is used when aligning ☆, and the correction value for □ is used when aligning □, and the drive amount M' is determined to drive the detector 14. This allows the mark pair to be positioned within the central area of the field of view 81 of the detector 14 even when imprinting a partial shot area, improving the detection accuracy of the alignment.

The pattern of the cured product formed by using the imprinting apparatus is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. The articles include electric circuit elements, optical elements, MEMS, recording elements, sensors, molds, etc. Examples of the electric circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensor, and FPGA. Examples of the molds include molds for imprinting.

The pattern of the cured material is used as it is as at least a part of the component of the article, or is used temporarily as a resist mask. After etching or ion implantation is performed in the substrate processing step, the resist mask is removed.

Next, an article manufacturing method will be described in which a pattern is formed on a substrate using an imprinting device, the substrate on which the pattern has been formed is processed, and an article is manufactured from the processed substrate. As shown in FIG. 8(a), a substrate 1z such as a silicon wafer having a workpiece 2z such as an insulator formed on its surface is prepared, and then an imprinting material 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, the state in which the imprinting material 3z in the form of multiple droplets has been applied onto the substrate is shown.

As shown in FIG. 8(b), the imprinting mold 4z is placed with the side on which the concave-convex pattern is formed facing the imprinting material 3z on the substrate. As shown in FIG. 8(c), the substrate 1z to which the imprinting material 3z has been applied is brought into contact with the mold 4z, and pressure is applied. The imprinting material 3z fills the gap between the mold 4z and the workpiece 2z. When light is irradiated through the mold 4z in this state as hardening energy, the imprinting material 3z hardens.

As shown in FIG. 8(d), after the imprint material 3z is cured, the mold 4z and the substrate 1z are separated, and a pattern of the cured product of the imprint material 3z is formed on the substrate 1z. This cured product pattern has a shape in which the concave portions of the mold correspond to the convex portions of the cured product, and the convex portions of the mold correspond to the concave portions of the cured product, i.e., the concave-convex pattern of the mold 4z is transferred to the imprint material 3z.

As shown in FIG. 8(e), when etching is performed using the pattern of the cured material as an etching-resistant mask, the portions of the surface of the workpiece 2z where there is no cured material or where only a thin layer remains are removed, forming grooves 5z. As shown in FIG. 8(f), when the pattern of the cured material is removed, an article is obtained in which grooves 5z are formed on the surface of the workpiece 2z. Here, the pattern of the cured material is removed, but it may also be used as an interlayer insulating film included in a semiconductor element, or as a component of an article, without being removed after processing.

The invention is not limited to the above-described embodiment, and various modifications and variations are possible without departing from the spirit and scope of the invention. Therefore, the following claims are appended to disclose the scope of the invention.

NIL: Imprint device, 1: Substrate, 11: Mold, 14: Measuring instrument (scope), 40: Control unit

Claims (15)

An imprint apparatus that performs an imprint process for transferring a pattern of a mold to an imprint material arranged on a substrate, for a plurality of shot areas of the substrate, comprising:
a detector for detecting a first mark provided on the substrate and a second mark provided on the mold;
a control unit that controls positioning of the detector by a first drive amount by which the detector should be driven in order to place the first mark and the second mark within a specific region of a field of view of the detector, and a second drive amount based on a correction value that corrects the first drive amount,
the first driving amount and the correction value are stored in a storage unit,
The control unit drives the detector based on the second driving amount, aligns a shot area selected from the multiple shot areas with the mold based on the output of the detector, and updates the correction value stored in the memory unit based on the output of the detector when the alignment is performed . the alignment is performed by detecting, with the detector, a moire image or interference fringes formed by the first mark and the second mark when the mold and the substrate are in contact with each other via an imprint material.
The imprint apparatus according to claim 1 . the correction value is stored in the storage unit for each relative position of the first mark in the shot area.
3. The imprint apparatus according to claim 1, wherein the imprint apparatus is a liquid crystal display. the correction value is a deviation amount between a center position of a field of view of the detector and a representative position determined by the first mark and the second mark during alignment;
4. The imprint apparatus according to claim 1, wherein the imprinting device is a laser beam source. The correction value depends on the aberration of the detector.
5. The imprint apparatus according to claim 1, wherein the imprinting device is a laser beam source. The correction value depends on a drive error of a drive mechanism that drives the detector.
6. The imprint apparatus according to claim 1, The specific area is a central area of the visual field.
7. The imprint apparatus according to claim 1, wherein the imprint apparatus is a liquid crystal display. when an updated correction value is present as the correction value, the control unit controls positioning of the detector based on the first driving amount and the updated correction value.
The imprint apparatus according to any one of claims 1 to 7. A plurality of detectors including the detector are provided,
a plurality of first marks including the first mark are provided on the substrate, a plurality of second marks including the second mark are provided on the mold, each of the plurality of second marks corresponds to one of the plurality of first marks;
each of the plurality of detectors detects a relative position of one of the plurality of first marks and one of the plurality of second marks;
the storage unit holds a plurality of first driving amounts including the first driving amount and a plurality of correction values including the correction value, so as to correspond to each of the plurality of first marks;
The imprint apparatus according to any one of claims 1 to 8. the plurality of first driving amounts are different from one another, and the plurality of correction values are different from one another;
The imprint apparatus according to claim 9 . the control unit aligns the selected shot area with the mold based on a relative position of the first mark and the second mark obtained based on an output of the detector, and updates the correction value based on a position of at least one of the first mark and the second mark in the field of view of the detector driven according to the first driving amount.
The imprint apparatus according to any one of claims 1 to 10. An imprinting method for performing an imprinting process for transferring a pattern of a mold to an imprint material arranged on a substrate, on a plurality of shot areas of the substrate, the method comprising: storing a first driving amount for driving the detector in order to place a first mark provided in a shot area selected from the plurality of shot areas and a second mark provided on the mold within a specific area of a field of view of the detector, and a correction value for correcting the first driving amount , in a storage unit;
The imprint method comprises:
controlling the positioning of the detector by a second driving amount based on the first driving amount and the correction value ;
performing the imprint processing on a shot area selected from a plurality of shot areas of the substrate while aligning the selected shot area with the mold based on an output of the detector;
updating the correction value stored in the storage unit based on an output of the detector when the alignment is performed ;
1. An imprint method comprising: Forming a pattern on a substrate using an imprint apparatus according to any one of claims 1 to 11;
processing the patterned substrate to obtain an article;
A method for manufacturing an article, comprising: An imprint apparatus that performs an imprint process for transferring a pattern of a mold to an imprint material arranged on a substrate, for a plurality of shot areas of the substrate, comprising:
a detector for detecting a first mark provided on the substrate and a second mark provided on the mold;
a control unit that controls positioning of the detector based on a target position to which the detector is moved so that the first mark and the second mark are placed within a specific region of a field of view of the detector, the target position being stored in a storage unit, and a correction value for correcting the target position, the correction value being stored in the storage unit;
The control unit aligns the mold with a shot area selected from the plurality of shot areas based on the output of the detector positioned based on the target position and the correction value , and updates the correction value stored in the memory unit based on the output of the detector when the alignment is performed . 1. An imprint method for performing an imprint process for transferring a pattern of a mold to an imprint material disposed on a substrate, on a plurality of shot areas of the substrate, the method comprising:
a step of controlling positioning of the detector based on a target position to which the detector is moved so that a first mark provided in a shot area selected from the plurality of shot areas and a second mark provided on the mold are within a specific area of a field of view of the detector, the target position being stored in a storage unit, and a correction value for correcting the target position being stored in the storage unit;
performing the imprint processing on a selected shot area while aligning the selected shot area with the mold based on an output of the detector positioned based on the target position and the correction value;
updating the correction value stored in the storage unit based on an output of the detector when the alignment is performed;
1. An imprint method comprising:

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