IMPRINT METHOD, IMPRINT APPARATUS, AND ARTICLE MANUFACTURING METHOD

Abstract

To provide an imprint method advantageous in overlay accuracy.SOLUTION: An imprint method includes: an acquisition step of acquiring global alignment information containing information for specifying a position coordinate of each of a plurality of shot regions containing a first shot region and a second shot region of a substrate; a pre-alignment measurement step of measuring a relative position deviation between the second shot region and a type by the measurement part by moving the second shot region to a measurement position where the measurement is performed by a measurement part on the basis of the acquired global alignment information; and a control step of starting a contact step after the movement of the first shot region to an imprint position where the imprint processing is performed on the basis of the global alignment information and the measured relative position deviation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an imprint method, an imprint apparatus, and a method for manufacturing an article. [Background technology]

[0002] Imprinting apparatuses are being put to practical use as one of the lithography technologies for mass production of magnetic storage media and semiconductor devices. Imprinting apparatuses form patterns on substrates by bringing a mold on which a fine circuit pattern is formed into contact with an imprint material on a substrate such as a silicon wafer or a glass plate.

[0003] For example, in forming a circuit pattern for a semiconductor device, the overlay accuracy between a circuit pattern already formed on a substrate and a circuit pattern to be formed can be very important. Global alignment and die-by-die alignment can be adopted as alignment methods in an imprint apparatus. Global alignment is a method of estimating the positions of all shot areas based on the measurement results of marks in a plurality of sample shot areas on a substrate. Die-by-die alignment is a method of optically detecting a substrate-side mark and a mold-side mark for each shot area to correct misalignment between the substrate and the mold.

[0004] Patent Document 1 describes that rough alignment (pre-alignment) can be performed after global alignment and before die-by-die alignment. Patent Document 2 describes that pre-alignment involves detecting a mark on the mold and a mark on the wafer in a non-contact state between the resin applied to the wafer and the mold. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-076626 A [Patent Document 2] JP 2012-084732 A Summary of the Invention [Problem to be solved by the invention]

[0006] Pre-alignment is performed in the first shot area to be imprinted, or each time imprinting is performed, before the imprint material on the shot area is brought into contact with the mold. By performing pre-alignment, it is possible to reduce the initial relative positional deviation when the imprint material on the shot area is brought into contact with the mold.

[0007] However, when the shot area to be imprinted is a peripheral shot area located on the outer periphery of the substrate, the overlay accuracy may decrease due to factors such as restrictions on the placement of the marks or marks not being formed properly by a previous process.

[0008] Improvement of overlay accuracy is an important requirement in imprint technology in order to realize the formation of highly accurate multi-layer circuit patterns. The present invention provides an imprint method that is advantageous in terms of, for example, overlay accuracy. [Means for solving the problem]

[0009] According to one aspect of the present invention, there is provided an imprinting method for performing an imprinting process including a contacting step of bringing an imprinting material supplied onto a substrate into contact with a mold, a curing step of curing the imprinting material in a state in which the imprinting material and the mold are in contact with each other, and a demolding step of separating the imprinting material after the imprinting material has been cured from the mold, the method including the steps of: obtaining global alignment information including information for identifying position coordinates of each of a plurality of shot regions including a first shot region and a second shot region of the substrate; By performing global alignment measurement in which the position of a sample shot area among the plurality of shot areas is measured using an off-axis measurement unit, and based on the acquired global alignment information, Located in the vicinity of the sample shot area The second shot area is Alignment Move the measuring device to a measurement position where the measurement is performed by the measuring device, AlignmentAn imprint method is provided, comprising: a pre-alignment measurement process for measuring a relative positional deviation between the second shot area and the mold by a measurement unit; and a control process for starting the contact process after moving the first shot area to an imprint position where the imprint process is performed based on the global alignment information and the measured relative positional deviation. Effect of the Invention

[0010] According to the present invention, for example, it is possible to provide an imprint method that is advantageous in terms of overlay accuracy. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing the configuration of an imprint apparatus. [Diagram 2] 1 is a flowchart of an imprint process. [Diagram 3] 1A to 1C are views for explaining an imprint process. [Figure 4] 1 is a diagram illustrating an example of an imprint order for multiple shot areas of a substrate. [Diagram 5] FIG. 13 is a diagram showing an example of classification of peripheral shot regions and complete shot regions. [Figure 6] 11A and 11B are diagrams showing examples of mark arrangements in a peripheral shot area and a complete shot area. [Figure 7] 1 is a flowchart of an imprint process. [Figure 8] 1 is a flowchart of an imprint process. [Figure 9] 1A and 1B are diagrams for explaining imprint processing using a conventional MFD. [Figure 10] 1A to 1C are diagrams illustrating an imprint process using an MFD. [Figure 11] 5A to 5C are views for explaining measurement of a pre-alignment shot during global alignment. [Figure 12] 1A to 1C are diagrams illustrating a method for manufacturing an article according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, the embodiments will be 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 a number of features, not all of these features are essential to the invention, and the 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 duplicated descriptions are omitted.

[0013] First Embodiment FIG. 1 is a schematic diagram of an imprint apparatus 100 in an embodiment. In this specification and the drawings, directions are indicated in an XYZ coordinate system with a horizontal plane as the XY plane. In general, a substrate W, which is an object on which a pattern is to be formed, is placed on a substrate stage 104 so that its surface is parallel to the horizontal plane (XY plane). Therefore, in the following, directions perpendicular to each other in a plane along the surface of the substrate W are referred to as the X-axis and Y-axis, and a direction perpendicular to the X-axis and Y-axis is referred to as the Z-axis. In the following, directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are referred to as the X-direction, Y-direction, and Z-direction, respectively, and the rotation direction around the X-axis, the rotation direction around the Y-axis, and the rotation direction around the Z-axis are referred to as the θx direction, the θy direction, and the θz direction, respectively.

[0014] First, an overview of an imprinting apparatus according to an embodiment will be described. The imprinting apparatus is an apparatus that brings an imprinting material supplied onto a substrate into contact with a mold and applies energy for curing to the imprinting material, thereby forming a pattern of a cured material to which the concave-convex pattern of the mold has been transferred.

[0015] As the imprint material, a curable composition (sometimes called an uncured resin) that is cured by applying energy for curing is used. As the energy for curing, electromagnetic waves, heat, etc. can be used. The electromagnetic waves can be, for example, light having a wavelength selected from the range of 10 nm to 1 mm, 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. Among 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 can be arranged on the substrate in the form of droplets, or in the form of islands or films formed by connecting a plurality of droplets, by an imprint material supplying device. The viscosity of the imprint material (viscosity at 25° C.) can be, for example, 1 mPa·s to 100 mPa·s. Examples of the material of the substrate include glass, ceramics, metals, semiconductors, and resins. If necessary, a member made of a material different from that of 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.

[0016] In FIG. 1, the imprint apparatus 100 includes a curing unit 102, a mold holding unit 103, a substrate stage 104, a supply unit 105, a control unit 107, a TTM measurement unit 122, and an off-axis measurement unit 131.

[0017] The curing unit 102 emits light 109 (ultraviolet light) to cure the imprint material on the substrate in a state where the imprint material is in contact with the mold 108. The curing unit 102 may include a light source (not shown) and an optical element for adjusting the light 109 emitted from the light source to light appropriate for imprinting. The emitted light 109 passes through the mold 108 and is irradiated onto the imprint material on the substrate. Note that in this embodiment, the curing unit 102 is configured to emit light 109 in order to adopt a photocuring method, but if, for example, a thermal curing method is adopted, the curing unit 102 will include a heat source for curing the imprint material made of a thermosetting composition.

[0018] The mold 108 has a pattern portion 8a formed in a three-dimensional shape on a first surface facing the substrate 111. A concave-convex pattern to be transferred to the substrate, such as a circuit pattern, is formed on the pattern portion 8a. The mold 108 is made of a material capable of transmitting light 109, such as quartz. The mold 108 may have a shape having a cavity (concave) 8b on the opposite side to the first surface to facilitate deformation of the mold 108 in the Z direction. The cavity 8b has, for example, a circular planar shape as viewed from the Z direction, and a thickness (depth) is appropriately set depending on the size and material of the mold 108. In addition, a light transmitting member 113 is installed in an opening region 117 in the mold holding part 103 to close a space 112 surrounded by a part of the opening region 117 and the cavity 8b, and the pressure in the space 112 may be controlled by a pressure adjusting device (not shown). For example, when the mold 108 is brought into contact with the imprint material 114 on the substrate 111, the pressure in the space 12 is set higher than the outside thereof by a pressure adjusting device, thereby bending the pattern portion 8a into a convex shape toward the substrate 111. As a result, contact with the imprint material 114 begins from the center of the pattern portion 8a. Thereafter, by gradually reducing the pressure in the space 12, contact progresses from the center of the pattern portion 8a to the periphery. This prevents gas from being trapped between the pattern portion 8a and the imprint material 114, and allows the imprint material 114 to fill every corner of the uneven portions of the pattern portion 8a.

[0019] The mold holding unit 103, also called an imprint head, has a mold chuck 115 that attracts and holds the mold 108 by vacuum suction force or electrostatic force, and a mold driving unit 116 that holds the mold chuck 115 and moves the mold chuck 115 (i.e., the mold 108). The mold chuck 115 and the mold driving unit 116 have an opening area 117 in the center so that light 109 irradiated from the light source of the curing unit 102 is irradiated toward the substrate 111.

[0020] The mold holding unit 103 also has a shape correction unit 118 that corrects the shape of the mold 108 (pattern portion 8a) by applying an external force to multiple points on the side surface of the mold 108. The shape correction unit 118 can deform the shape of the mold 108 in accordance with the shape of the pattern already formed on the substrate 111.

[0021] The mold driving unit 116 moves the mold 108 in the Z direction so as to selectively contact and separate (release) the mold 108 from the imprint material 114 on the substrate 111. Examples of actuators that can be used for the mold driving unit 116 include a linear motor or an air cylinder. In addition, in order to accommodate high-precision positioning of the mold 108, the mold driving unit 116 may include a plurality of driving systems, such as a coarse movement driving system and a fine movement driving system. Furthermore, the mold driving unit 116 may have a position adjustment function not only in the Z direction but also in the X direction, Y direction, or θZ direction, a tilt function for correcting the inclination of the mold 108, and the like. Note that the contact and release operations in the imprint apparatus 100 may be realized by moving the mold 108 in the Z axis direction as described above, but may also be realized by moving the substrate stage 104 in the Z axis direction, or both of them may be moved relatively.

[0022] The substrate stage 104 holds and moves the substrate 111. The substrate stage 104 has a substrate chuck 119 (substrate holding unit) that holds the substrate 111 by suction force, and a stage driving unit 120 that holds the substrate chuck 119 and allows it to move within the XY plane. The substrate chuck 119 may have a plurality of suction units (not shown) that suction-hold the back surface of the substrate 111 in a plurality of regions. These suction units are each connected to a pressure adjustment device different from the above. Each pressure adjustment device adjusts the pressure between the substrate 111 and the suction unit to generate a suction force, thereby holding the substrate 111 on the chuck surface. At this time, the pressure value (suction force) can be changed independently for each suction unit. The number of divisions (installation number) of the suction units is not particularly limited, and may be any number. The substrate stage 104 also has a reference mark 121 used when aligning the mold 108 on its surface. The stage driving unit 120 may employ, for example, a linear motor as an actuator. The stage driving unit 120 may also include a plurality of driving systems, such as a coarse movement driving system and a fine movement driving system, for each of the X and Y directions. Furthermore, the stage driving unit 120 may have a driving system for adjusting the position in the Z direction, a position adjustment function for the θ direction of the substrate 111, or a tilt function for correcting the inclination of the substrate 111. By driving the substrate stage 104, the substrate 111 can be aligned with the mold 108.

[0023] The supply unit 105 supplies (places) the imprint material on the substrate 111. The supply unit 105 has a discharge nozzle that discharges the imprint material. The amount of the imprint material discharged from the discharge nozzle is appropriately determined depending on the desired thickness of the imprint material 114 formed on the substrate 111, the density of the pattern to be formed, and the like.

[0024] The TTM measurement unit 122 is installed, for example, in the opening region 117, and has a scope including an optical system and an imaging system for measuring the positional deviation in the X and Y directions between the alignment mark formed on the substrate 111 and the alignment mark formed on the mold 108. Note that "TTM" is an abbreviation for "Through The Mold" and is intended to observe the mark on the mold side and the mark on the substrate side through the mold.

[0025] On the other hand, the off-axis measurement unit 131 has a scope including an optical system and an imaging system for detecting the alignment mark formed on the substrate 111 without using the mold 108. By using the TTM measurement unit 122 and the off-axis measurement unit 131, the relative positioning of the mold 108 and the substrate 111 can be performed.

[0026] The imprint apparatus 100 also includes a base plate 124 on which the substrate stage 104 is placed, a bridge plate 125 to which the mold holding part 103 is fixed, and supports 126 extending from the base plate 124 and supporting the bridge plate 125. The imprint apparatus 100 also includes a mold transport mechanism (not shown) that transports the mold 108 from outside the apparatus to the mold holding part 103, and a substrate transport mechanism (not shown) that transports the substrate 111 from outside the apparatus to the substrate stage 104.

[0027] The control unit 107 can control the operation and adjustment of each component of the imprint apparatus 100. The control unit 107 is configured as a computer including, for example, a processor (CPU) and a memory, and can be connected to each component of the imprint apparatus 100 via a line and control each component according to a program. The control unit 107 may be configured integrally with other parts of the imprint apparatus 100 (in a common housing), or may be configured separately from the other parts of the imprint apparatus 100 (in a different housing).

[0028] [Imprint process overview] 2 and 3, an imprint process (imprint method) for forming a pattern on a substrate by bringing an imprint material 114 on the substrate into contact with a mold 108 will be described. In S300, the control unit 107 controls the mold transport mechanism to transport the mold 108 specified in the lot from the mold stocker to the mold holding unit 103, and fix it to the mold chuck 115. In S302, the control unit 107 controls the substrate transport mechanism to transport the substrate 111 to be processed from the substrate carrier to the substrate stage 104, and fix it to the substrate chuck 119.

[0029] Next, the control unit 107 performs pre-alignment measurement to measure the relative position between the mold 108 and each shot in the substrate 111. In S304, the control unit 107 observes the mold side mark 63 on the mold 108 with the TTM measurement unit 122 and measures the position. Next, the control unit 107 observes a mark (not shown) on the substrate stage 104 with the TTM measurement unit 122 and measures the position of the substrate stage 104 with respect to the TTM measurement unit 122.

[0030] In S306, global alignment measurement is performed. In the global alignment measurement, the control unit 107 drives the substrate stage 104 so that the substrate 111 is positioned under the off-axis measurement unit 131. Thereafter, the control unit 107 uses the off-axis measurement unit 131 to measure the positional deviation of marks in a plurality of sample shot areas in the substrate 111 based on the substrate stage 104. The positional deviation here refers to the positional deviation of the marks with respect to the measurement position that is detected when the substrate stage 104 is driven so that the marks in each sample shot area are positioned at the measurement position of the off-axis measurement unit 131 based on the design data of the shot arrangement. Thereafter, the control unit 107 performs statistical processing such as abnormal value processing and function fitting based on the obtained positional deviation of each sample shot area. Through this statistical processing, the position coordinates of all shot areas on the substrate 111 are identified and global alignment information including information on the positional relationship between the plurality of shot areas is acquired.

[0031] The control unit 107 specifies a shot area that has not yet been imprinted. An area in the substrate to be imprinted (area to be processed) is called a "shot area (or simply a shot)". The imprinting order may be, for example, as shown in FIG. 4, in the order of Shot 1, 2, 3, 4, ..., 6, 7, 8, ..., 14, ..., which are consecutive shot areas on the substrate 111. The imprinting order is not limited to this order, and orders such as a staggered order and random order can be set, but the imprinting order in which adjacent shot areas are imprinted sequentially as shown in FIG. 4 is a typical example that is advantageous in terms of throughput. The shot layout and the imprinting order are stored in advance as a recipe in a memory or the like possessed by the control unit 107.

[0032] In order to align the substrate and the mold with higher accuracy, pre-alignment measurement is performed in S308. Pre-alignment measurement is performed as follows. Based on the global alignment information acquired in S306, the control unit 107 controls the substrate stage 104 so that the shot area to be imprinted first is located at a measurement position corresponding to the imprint position under the pattern portion 8a of the mold 108. Thereafter, as shown in FIG. 3(a), the control unit 107 simultaneously observes the substrate-side mark 62 and the mold-side mark 63 using the TTM measurement unit 122 and measures the relative positional deviation between them.

[0033] In S310, the control unit 107 controls the substrate stage 104 so that the target shot area (the shot area that will undergo imprint processing) is positioned at the supply position below the supply unit 105, and the supply unit 105 supplies the imprint material 114 to the target shot area.

[0034] S312 is a contact step. In this contact step, first, the control unit 107 controls the substrate stage 104 so that the target shot area is positioned under the mold holding unit 103 (imprint position). At this time, the control unit 107 drives the substrate stage 104 based on the global alignment information acquired in S306 and the relative positional deviation obtained by the pre-alignment measurement in S308. Thereafter, the control unit 107 controls the mold holding unit 103 to drive the mold 108 in the Z direction, thereby bringing the imprint material 114 on the target shot area into contact with the pattern portion 8a of the mold 108. As described above, the pressure in the space 12 can be adjusted at the time of contact in order to prevent air bubbles from being generated. Due to this contact, as shown in FIG. 3(b), the imprint material 114 flows along the concave-convex pattern formed in the pattern portion 8a, and fills the space between the substrate 111 and the pattern portion 8a.

[0035] In S314, the control unit 107 uses the TTM measurement unit 122 to measure the relative positional deviation between the substrate-side mark 62 and the mold-side mark 63, and controls the substrate stage 104 and the shape correction unit 118 so that the amount of relative positional deviation falls within a predetermined tolerance. In this way, alignment between the pattern portion 8a of the mold 108 and the target shot area is performed. This alignment is performed for each shot area, and is called die-by-die alignment.

[0036] In S316, while the mold 108 and the imprint material 114 are in contact with each other, the control unit 107 causes the curing unit 102 to irradiate light 109 to cure the imprint material (curing step). After the imprint material 114 has cured, in S318, the control unit 107 controls the mold holding unit 103 to separate the cured imprint material 114 from the mold 108, as shown in Fig. 3(c) (mold releasing step).

[0037] In S320, the control unit 107 determines whether there is a shot area to be processed next. If there is a shot area to be processed next, the process returns to S310, and the imprint process of the next shot area is performed. In the imprint process of the next shot area, the shot area is moved from the supply position of the imprint material to under the mold holding unit 103 for the contact step in S312. At this time, too, the substrate stage 104 is driven based on the global alignment information acquired in S306 and the relative positional deviation obtained by the pre-alignment measurement in S308. If it is determined in S320 that there is no shot area to be processed next, the process proceeds to S322. In this manner, the imprint process is performed on all the shot areas specified in the lot, and a pattern is formed on the entire surface of the substrate 111.

[0038] In S322, the control unit 107 controls the substrate transport mechanism to collect the substrate 111 that has been subjected to the imprint processing and is placed on the substrate chuck 119. In S324, the control unit 107 determines whether there is a substrate to be processed next. If there is a substrate to be processed next, the processing returns to S30. 2 Then, the process returns to step S325, and the imprint process is performed on the next substrate. If there is no substrate to be processed next, the process proceeds to step S326. In step S326, the control unit 107 controls the mold transport mechanism to retrieve the mold 108 held by the mold chuck 115.

[0039] [Improvement of pre-alignment measurement] The die-by-die alignment performed in S314 aligns the target shot area with the pattern portion 8a of the mold 108. Since the imprint material 114 on the substrate 111 and the mold 108 are in contact with each other during the die-by-die alignment, the amount of alignment is limited and the alignment takes time. Therefore, it is necessary to reduce the amount of alignment between the substrate 111 and the mold 108 during the die-by-die alignment. The pre-alignment measurement in S308 performed before the imprint material 114 on the substrate 111 and the mold 108 are brought into contact with each other determines the amount of alignment between the substrate 111 and the mold 108 during the die-by-die alignment. The improved pre-alignment measurement will be described below.

[0040] As described above, according to the example of FIG. 4, imprinting is performed on the substrate 111 in the order of successive Shots 1, 2, 3, 4, ..., 6, 7, 8, ..., 14, .... Incidentally, these shot areas also include "peripheral shot areas" located on the periphery of the substrate 111. The peripheral shot areas are also called partial fields (PF). Shot areas other than the peripheral shot areas are called complete shot areas or full fields (FF). For the purpose of maximizing the effective area of ​​the substrate 111 (the area of ​​the area to which a pattern is transferred), imprint processing can also be performed on the peripheral shot areas.

[0041] FIG. 5 is a diagram showing an example of classification of peripheral shot areas (PF) and complete shot areas (FF). The "peripheral shot area" typically includes a "missing shot area" in which a part of the pattern portion 8a of the mold 108 protrudes from the peripheral portion (outer periphery) of the substrate 111 when the mold 108 is brought into contact with the imprint material on the substrate 111, and only a part of the pattern portion 8a is transferred. Even if there is no "missing", a shot area whose corner only touches the peripheral portion of the substrate or a shot area located close to the peripheral portion of the substrate may also be classified as a peripheral shot area. For example, an area within a predetermined distance (e.g., 3 mm) from the outer periphery of the substrate is susceptible to the influence of the previous process, and may be regarded as an invalid area that is not subject to imprinting. A shot area partly overlapping such an invalid area may also be classified as a peripheral shot area.

[0042] As shown in FIG. 6, the PF has a smaller area than the FF, so the degree of freedom in mark placement is restricted compared to the FF. For example, in the FF, marks (AM131, AM132, AM133, AM134) can be placed at the four corners, whereas in the PF, only three marks (AM011, AM012, AM013) can be placed at close intervals. For this reason, in the PF, the averaging effect is small when calculating translation components by statistically processing each mark, so the accuracy may decrease. In the PF, the span between the mark and the scope is also short because of restrictions on the placement of marks (distance between marks). This may increase correction errors such as rotation components. In addition, in the PF, there is a higher possibility that the marks are not formed properly due to the process in the previous step. For example, the mark AM013 is located near the invalid area on the outer periphery of the substrate. Marks at such positions may not be formed properly. If pre-alignment measurement is performed using marks that are not formed properly, the alignment accuracy decreases and the alignment amount during die-by-die alignment increases.

[0043] In this embodiment, the shot area where the pre-alignment measurement in S308 is performed is not the target shot area, but the FF that is geometrically closest to the target shot area. In the example of FIG. 4, Shot1 (first shot area) where imprint is performed first is the PF. According to this embodiment, when Shot1 is the target shot area, Shot13 (second shot area), which is the FF that is geometrically closest to Shot1, is selected as the shot area where the pre-alignment measurement in S308 is performed. The geometrically closest shot area refers to, for example, a shot area where the distance between the shot centers is the smallest. Note that the relationship between the first shot area and the second shot area is not necessarily limited to the relationship between the PF and the FF, and may be any relationship that can obtain sufficient effects from the viewpoints of the accuracy and productivity of the pre-alignment measurement.

[0044] FIG. 7 is a flowchart of the imprint process according to this embodiment. This flowchart is generally similar to the flowchart of FIG. 2, but S308' is executed instead of S308 as the pre-alignment measurement. In S308', the pre-alignment measurement is performed in a shot area different from the target shot area. For example, as described above, when Shot1 is the target shot area, the pre-alignment measurement is performed not in Shot1 but in Shot13, which is the geometrically nearest FF from Shot1. Specifically, the control unit 107 controls the substrate stage 104 based on the global alignment information acquired in S306 so that Shot13 is located at a measurement position corresponding to the imprint position under the pattern portion 8a of the mold 108. Thereafter, the control unit 107 uses the TTM measurement unit 122 to simultaneously observe the substrate side mark 62 and the mold side mark 63, and measures the relative positional deviation between them.

[0045] Thereafter, in S310, the control unit 107 controls the substrate stage 104 so that Shot1, which is a target shot area, is located at a supply position below the supply unit 105, and the supply unit 105 supplies the imprint material 114 to Shot1. In S312, the control unit 107 controls the substrate stage 104 so that Shot1 is located below the mold holding unit 103 (imprint position). At this time, the control unit 107 drives the substrate stage 104 based on the global alignment information acquired in S306 and the result obtained by the pre-alignment measurement in S308' (i.e., the pre-alignment measurement at Shot13).

[0046] Thereafter, the control unit 107 controls the mold holding unit 103 to drive the mold 108 in the Z direction, thereby bringing the imprint material 114 on Shot 1, which is the target shot area, into contact with the pattern portion 8 a of the mold 108. Also, in the imprint processes from Shot 2 onwards, the substrate stage 104 is driven based on the global alignment information acquired in S306 and the results obtained by the pre-alignment measurement for Shot 13 in S308'.

[0047] In the above example, the substrate stage is driven to the next shot position based on the pre-alignment measurement result of Shot 13, but the present invention is not limited to this. For example, the target position of the substrate stage may be corrected based on the measurement value of the TTM measurement unit 122 during die-by-die alignment, in addition to the pre-alignment measurement result. Specifically, the substrate stage 104 is driven using the positional deviation measurement value at the start of die-by-die alignment as the correction amount. In addition, after imprinting a plurality of shot areas, the positional deviation measurement value at the start of die-by-die alignment may be statistically processed, and the substrate stage position may be corrected based on the result. This makes it possible to further reduce the alignment amount during die-by-die alignment.

[0048] Thus, according to this embodiment, when the target shot area has restrictions on the placement and formation accuracy of marks such as PF, pre-alignment measurement is performed in a FF (e.g., Shot 13) near the target shot area. Therefore, it is less susceptible to restrictions on the placement of the substrate-side marks 62 measured by the TTM measurement unit 122, or problems such as the substrate-side marks 62 not being formed properly due to a previous process. As a result, the amount of alignment between the substrate 111 and the mold 108 in die-by-die alignment can be reduced.

[0049] In this embodiment, the case where the pre-alignment measurement is performed only in Shot1, which is the first target shot area, has been described. However, the pre-alignment measurement may be performed for each shot area, or may be performed at a predetermined shot area interval of two shot areas or more and less than all shot areas, such as when the column or row of the shot area is changed. When the pre-alignment measurement is performed for each shot area, the pre-alignment measurement is performed before the imprint material is supplied to the target shot area, and after the imprint material is supplied, the substrate stage is driven based on the pre-alignment measurement result. At this time, when the target shot area is PF, the unimprinted shot area (FF) geometrically closest to the target shot area is selected as the shot area for the pre-alignment measurement. The same applies when the pre-alignment measurement is performed at a shot area interval of two shot areas or more and less than all shot areas.

[0050] Also, the method of discharging the imprint material may not be the inkjet method, and the imprint process as described above may be performed on a substrate on which the imprint material has already been placed. In this case, the imprint material supply step S310 in Fig. 7 is eliminated, and S312 is performed immediately after the pre-alignment measurement in S308'.

[0051] (Modification) FIG. 8 is a flowchart according to a modified example of FIG. 7. In FIG. 8, after the global alignment in S306 is completed, in S307, the control unit 107 determines whether the target shot area is a PF by, for example, referring to a shot layout stored as a recipe in a memory. Alternatively, the recipe may have information on whether each shot area is a FF or a PF in advance. If the target shot area is a PF, the process proceeds to S308' similar to FIG. 7, and pre-alignment measurement is performed in a nearby FF different from the target shot area. On the other hand, if the target shot area is a FF rather than a PF, there is no need to bother to use information on other shot areas, so the process proceeds to S308 similar to FIG. 2, and pre-alignment measurement is performed in the target shot area itself.

[0052] As described above, according to this embodiment, it is possible to reduce the amount of alignment during die-by-die alignment, and it is possible to form a pattern while maintaining good overlay accuracy without reducing productivity even when the imprint process is repeatedly performed.

[0053] <Second embodiment> In the first embodiment, the imprint process is described as SFD (Single Field Dispense), but in this embodiment, the imprint process is performed by MFD (Multi Field Dispense). In the SFD, as described in the first embodiment, a sequence of imprint material supply, contact, hardening, and release is performed for each shot area. In contrast, in the MFD, imprint material is continuously supplied to two or more shot areas, and then a sequence of contact, hardening, and release is performed for each shot area to which the imprint material is supplied. The MFD has a smaller substrate stage drive amount than the SFD, which performs an imprint material supply operation for each shot area, and therefore can improve productivity. FIG. 9 shows an example of imprint process when MFD is performed. In the MFD, imprint material is continuously supplied to two or more shot areas, and then contact and hardening are performed for each shot area. Therefore, the exposure light for hardening may affect the imprint material already placed in the adjacent shot areas. To mitigate such effects, in the example of FIG. 9, contact, hardening, and release are performed by skipping one shot area.

[0054] First, the imprint process using a conventional MFD will be described. In the conventional imprint process, the pre-alignment measurement is performed on Shot1 (first pre-alignment shot), which is the first target shot area in the shot area row. For Shot1, the TTM measurement unit 122 simultaneously observes the substrate side mark 62 and the mold side mark 63 to measure the positional deviation. After the measurement, the substrate stage 104 moves to below the supply unit 105. Thereafter, the control unit 107 controls the substrate stage 104 and the supply unit 105 to successively supply the imprint material 114 to Shot1, Shot2, and Shot3, which exist on the substrate 111, one shot area apart. Next, the substrate stage 104 is driven to place Shot1, to which the imprint material 114 has been supplied, at a predetermined position (imprint position) below the mold holding unit 103. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement at Shot1. The mold holding unit 103 drives the mold 108 in the Z direction to bring the pattern portion 8a of the mold 108 into contact with the imprint material 114 on Shot 1, thereby performing die-by-die alignment. Thereafter, the imprint material 114 is cured and released, and the imprint process of Shot 1 is completed.

[0055] Next, Shot 2 is placed at the imprint position below the mold holding part 103 by driving the substrate stage 104. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement in Shot 1. Thereafter, die-by-die alignment, curing, and demolding are performed, and the imprint process of Shot 2 is completed. The imprint process of Shot 3 is performed in the same manner.

[0056] Thereafter, pre-alignment measurement is performed again at Shot 4 (second pre-alignment shot) between Shot 1 and Shot 2. For Shot 4, the TTM measurement unit 122 simultaneously observes the substrate side mark 62 and the mold side mark 63 to measure the positional deviation. After the measurement, the substrate stage 104 moves to below the supply unit 105. Thereafter, the control unit 107 controls the substrate stage 104 and the supply unit 105 to successively supply the imprint material 114 to Shot 4, Shot 5, and Shot 6, which exist on the substrate 111 at intervals of one shot area. Next, the substrate stage 104 is driven to position Shot 4, to which the imprint material 114 has been supplied, at the imprint position below the mold holding unit 103. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement at Shot 4. The mold holding unit 103 drives the mold 108 in the Z direction to bring the pattern portion 8a of the mold 108 into contact with the imprint material 114 on Shot 4, thereby performing die-by-die alignment. Thereafter, the imprint material 114 is cured and released, and the imprint process of Shot 4 is completed.

[0057] Next, Shot 5 is placed at the imprint position below the mold holding part 103 by driving the substrate stage 104. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement in Shot 4. Thereafter, die-by-die alignment, curing, and demolding are performed, and the imprint process of Shot 5 is completed. Similarly, the imprint process of Shot 6 is also performed.

[0058] Thereafter, each time the shot area starts a new line, pre-alignment is performed by the first pre-alignment shot and the second pre-alignment shot. According to such a conventional example, since the pre-alignment is performed in the PF, there is a possibility that the accuracy of the pre-alignment is reduced.

[0059] Next, the imprint process by the MFD in this embodiment will be described with reference to FIG. 10. In the imprint process of this embodiment, the first pre-alignment is performed in Shot 2. For Shot 2, the TTM measurement unit 122 simultaneously observes the substrate side mark 62 and the mold side mark 63 to measure the positional deviation. After the measurement, the substrate stage 104 moves to below the supply unit 105. Thereafter, the control unit 107 controls the substrate stage 104 and the supply unit 105 to successively supply the imprint material 114 to Shot 1, Shot 2, and Shot 3 present on the substrate 111, one shot apart from the other. Next, the substrate stage 104 is driven to position Shot 1, to which the imprint material 114 has been supplied, at the imprint position below the mold holding unit 103. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement in Shot 2. The mold holding unit 103 drives the mold 108 in the Z direction to bring the pattern portion 8a of the mold 108 into contact with the imprint material 114 on Shot 1, thereby performing die-by-die alignment. Thereafter, the imprint material 114 is cured and released, and the imprint process of Shot 1 is completed.

[0060] Next, Shot 2 is placed at the imprint position below the mold holding unit 103 by driving the substrate stage 104. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement in Shot 2. Thereafter, die-by-die alignment, curing, and demolding are performed, and the imprint process of Shot 2 is completed. The imprint process of Shot 3 is performed in the same manner.

[0061] Thereafter, pre-alignment measurement is performed again with Shot 5 as the second pre-alignment shot. For Shot 5, the TTM measurement unit 122 simultaneously observes the substrate side mark 62 and the mold side mark 63 to measure the positional deviation. After the measurement, the substrate stage 104 moves to below the supply unit 105. The control unit 107 then controls the substrate stage 104 and the supply unit 105 to successively supply the imprint material 114 to Shot 4, Shot 5, and Shot 6 that exist on the substrate 111, spaced apart by one shot area. Next, the substrate stage 104 is driven to position Shot 4, to which the imprint material 114 has been supplied, at the imprint position below the mold holding unit 103. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement at Shot 5. The mold holding unit 103 drives the mold 108 in the Z direction to bring the pattern portion 8a of the mold 108 into contact with the imprint material 114 on Shot 4, thereby performing die-by-die alignment. Thereafter, the imprint material 114 is cured and released, and the imprint process of Shot 4 is completed.

[0062] Next, Shot 5 is placed at the imprint position below the mold holding part 103 by driving the substrate stage 104. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement of Shot 5. Thereafter, die-by-die alignment, curing, and demolding are performed, and the imprint process of Shot 5 is completed. The imprint process of Shot 6 is performed in the same manner.

[0063] Next, the shot area is changed to a new line, and pre-alignment measurement is performed on Shot 11 as the first pre-alignment shot. After the positional deviation is measured for Shot 11, the substrate stage 104 moves to below the supply unit 105. Thereafter, the control unit 107 controls the substrate stage 104 and the supply unit 105 to successively supply the imprint material 114 to Shot 7, Shot 8, Shot 9, and Shot 10 on the substrate 111, which are present at intervals of one shot area. Next, the substrate stage 104 is driven to position Shot 7, to which the imprint material 114 has been supplied, at the imprint position below the mold holding unit 103. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement of Shot 11. The mold holding unit 103 drives the mold 108 in the Z direction to bring the pattern portion 8a of the mold 108 into contact with the imprint material 114 on Shot 7, and die-by-die alignment is performed. Thereafter, the imprint material 114 is cured and released, and the imprint process of Shot 7 is completed.

[0064] Next, Shot 8 is placed at the imprint position below the mold holding part 103 by driving the substrate stage 104. At this time, the substrate stage 104 is driven based on the global alignment information and the result of the pre-alignment measurement in Shot 11. Thereafter, die-by-die alignment, curing, and demolding are performed, and the imprint process of Shot 8 is completed. The imprint processes of Shot 9 and Shot 10 are performed in the same manner.

[0065] Next, pre-alignment measurement is performed again with Shot 11 as the second pre-alignment shot. Similarly, imprint processing is performed for Shot 11, Shot 12, Shot 13, and Shot 14. Thereafter, each time a shot area starts, a first pre-alignment shot and a second pre-alignment shot are selected and pre-alignment measurement is performed.

[0066] In the example of FIG. 5 in the first embodiment, Shot 74 and Shot 77 are defined as PFs, but even PFs may have a large area and may be able to ensure the required accuracy of pre-alignment measurement. In that case, for example, as shown in FIG. 10, Shot 74 can be used as the first pre-alignment shot and Shot 77 can be used as the second pre-alignment shot. When imprinting the row including Shot 73 to Shot 78, there are no FFs on which imprint processing has not been performed (because Shot 74 and Shot 77 are defined as PFs). However, by using shot areas such as Shot 74 and Shot 77 that are larger in area than Shot 73 and Shot 76, the accuracy of pre-alignment measurement can be improved.

[0067] In addition, in the present embodiment, for example, the pre-alignment measurement is performed in Shot 2, and then imprinting is performed in the order of Shot 1, Shot 2, and Shot 3. However, the present invention is not limited to this. For example, after the pre-alignment measurement is performed in Shot 2, imprinting may be performed in the order of Shot 2, Shot 1, and Shot 3.

[0068] <Third embodiment> In the third embodiment, a method for selecting a pre-alignment shot will be described. As described in the first embodiment, in the imprint apparatus, the off-axis measurement unit 131 and the TTM measurement unit 122 are used to individually measure the positions of the substrate 111 and the mold 108 based on the apparatus coordinates. The TTM measurement unit 122 measures the position of the mold 108 based on the position reference of the TTM measurement unit 122 by observing the mold side mark 63. Meanwhile, the substrate stage 104 holding the substrate 111 moves below the off-axis measurement unit 131, and the off-axis measurement unit 131 is used to perform global alignment measurement for estimating the position coordinates of all shot areas on the substrate 111. In the global alignment measurement, the off-axis measurement unit 131 measures marks of a plurality of sample shot areas on the substrate 111, thereby measuring the positions of each sample shot area in the substrate 111 based on the substrate stage 104. After the global alignment measurement, the above-described pre-alignment measurement is performed for the designated shot area.

[0069] FIG. 11 shows an example of this embodiment. In global alignment measurement, the control unit 107 drives the substrate stage 104 to sequentially send each of the sample shot areas Shot1′ to Shot6′ to the measurement position (first measurement position) of the off-axis measurement unit 131. Thereafter, the off-axis measurement unit 131 is used to measure the marks of each sample shot area. At this time, when the off-axis measurement unit 131 is measuring Shot6′, Shot6″ is located near the measurement position (second measurement position) where the measurement is performed by the TTM measurement unit 122. Therefore, the control unit 107 selects Shot6″ as the pre-alignment shot. After Shot6′ is measured by the off-axis measurement unit 131, the control unit 107 moves Shot6″ selected as the pre-alignment shot to the measurement position where the measurement is performed by the TTM measurement unit 122. Thereafter, Shot6″ is measured by the TTM measurement unit 122 as the pre-alignment shot. This allows the driving distance of the substrate stage to be shortened, thereby improving productivity.

[0070] <Embodiment of the article manufacturing method> The pattern of the cured product formed by using the imprint 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 sensors, and FPGAs.

[0071] The pattern of the cured product is used as it is as at least a part of a component of the article, or is used temporarily as a resist mask, which is removed after etching or ion implantation in a substrate processing step.

[0072] Next, a method for manufacturing an article will be described. In step SA of Fig. 12, a substrate 1z such as a silicon substrate having a workpiece 2z such as an insulator formed on its surface is prepared, and then an imprint material 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, a state in which the imprint material 3z in the form of multiple droplets is applied onto the substrate is shown.

[0073] In step SB of Fig. 12, the mold 4z for imprinting is placed with the side on which the concave-convex pattern is formed facing the imprint material 3z on the substrate. In step SC of Fig. 12, the substrate 1z to which the imprint material 3z has been applied is brought into contact with the mold 4z, and pressure is applied. The imprint 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 energy for curing, the imprint material 3z is cured.

[0074] 12, 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. In this cured product pattern, the recesses of the mold correspond to the protrusions of the cured product, and the protrusions of the mold correspond to the recesses of the cured product, i.e., the recessed and protruding patterns of the mold 4z are transferred to the imprint material 3z.

[0075] In step SE of Fig. 12, etching is performed using the pattern of the cured material as an etching-resistant mask, and the portions of the surface of the workpiece 2z where there is no cured material or where only a thin layer remains are removed to form grooves 5z. In step SF of Fig. 12, the pattern of the cured material is removed to obtain an article 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 be used as an interlayer insulating film included in a semiconductor element or the like, that is, a component of an article, without being removed after processing.

[0076] (Other embodiments) The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) for implementing one or more of the functions.

[0077] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0078] 100: imprint apparatus, 103: mold holding unit, 104: substrate stage, 105: supply unit, 107: control unit, 122: TTM measurement unit, 131: off-axis measurement unit

Claims

1. An imprinting method for performing an imprinting process, the method including: a contacting step of bringing an imprinting material supplied onto a substrate into contact with a mold; a curing step of curing the imprinting material in a state in which the imprinting material and the mold are in contact with each other; and a demolding step of separating the imprinting material after the imprinting material has been cured from the mold, the method comprising the steps of: an acquisition step of acquiring global alignment information including information for identifying position coordinates of each of a plurality of shot areas including a first shot area and a second shot area of ​​the substrate by global alignment measurement that measures a position of a sample shot area among the plurality of shot areas using an off-axis measurement unit; a pre-alignment measurement step of moving the second shot area located near the sample shot area to a measurement position where measurement is performed by an alignment measurement unit based on the acquired global alignment information, and measuring a relative positional deviation between the second shot area and the mold by the alignment measurement unit; a control step of moving the first shot area to an imprint position where the imprint processing is performed based on the global alignment information and the measured relative positional deviation, and then starting the contact step; 1. An imprint method comprising the steps of:

2. 2. The imprinting method according to claim 1, further comprising an alignment step of measuring a relative positional deviation between the first shot area and the mold while the imprint material on the first shot area is in contact with the mold by the contact step started by the control step, and aligning the first shot area with the mold based on the relative positional deviation.

3. 3. The imprint method according to claim 1, wherein the second shot area is a shot area having a full field to which the entire pattern of the mold is transferred, and is not a peripheral shot area located on the periphery of the substrate.

4. 4. The imprint method according to claim 3, wherein the first shot area is a shot area having a partial field to which only a part of the pattern of the mold is transferred, and is the peripheral shot area.

5. The imprint method according to claim 4 , wherein the second shot area is a shot area in which a distance between shot centers is minimum with respect to the first shot area.

6. a supply step of moving the first shot area to a supply position of the imprint material after the pre-alignment measurement step, and supplying the imprint material onto the first shot area at the supply position, The control step moves the first shot area from the supply position to an imprint position where the imprint processing is performed based on the global alignment information and the measured relative positional deviation, and then starts the contact step. The imprint method according to any one of claims 1 to 5.

7. The imprint method according to claim 6 , wherein the supplying step supplies the imprint material to two or more shot regions consecutively before the contacting step.

8. The imprint method according to claim 6 , wherein the supplying step supplies the imprint material to two or more shot areas successively, every other shot area, before the contacting step.

9. An imprinting method for carrying out an imprinting process including a contacting step of bringing an imprinting material supplied onto a substrate into contact with a mold, a curing step of curing the imprinting material while the imprinting material and the mold are in contact with each other, and a demolding step of separating the imprinting material after the imprinting material has been hardened from the mold, a global alignment measurement process of measuring a position of a sample shot area among the plurality of shot areas using an off-axis measurement unit to acquire global alignment information including information specifying position coordinates of each of the plurality of shot areas including a first shot area and a second shot area of ​​the substrate; a pre-alignment measurement step of moving the second shot area to a measurement position where measurement is performed by an alignment measurement unit based on the acquired global alignment information, and measuring a relative positional deviation between the second shot area and the mold by the alignment measurement unit; a control step of moving the first shot area to an imprint position where the imprint processing is performed based on the global alignment information and the measured relative positional deviation, and then starting the contact step; having The pre-alignment measurement step selects, as the second shot area, a shot area located near a second measurement position where measurement is performed by the alignment measurement unit when the sample shot area is located at a first measurement position where measurement is performed by the off-axis measurement unit in the global alignment measurement step, moves the shot area selected as the second shot area to the second measurement position after measurement of the sample shot area by the off-axis measurement unit, and measures a relative positional deviation between the second shot area and the mold by the alignment measurement unit.

1. An imprint method comprising:

10. An imprinting apparatus for performing an imprinting process including a contacting step of bringing an imprinting material supplied onto a substrate into contact with a mold, a curing step of curing the imprinting material in a state in which the imprinting material and the mold are in contact with each other, and a demolding step of separating the imprinting material after the curing from the mold, a substrate stage that holds and moves the substrate; an alignment measurement unit that measures a relative positional deviation between the mold and a shot area of ​​the substrate held by the substrate stage; A control unit that controls execution of the imprint process; The control unit includes: acquiring global alignment information including information specifying position coordinates of each of a plurality of shot areas including a first shot area and a second shot area of ​​the substrate by global alignment measurement that measures a position of a sample shot area among the plurality of shot areas using an off-axis measurement unit; based on the acquired global alignment information, moving the second shot area located near the sample shot area to a measurement position where measurement is performed by the alignment measurement unit, and performing pre-alignment measurement using the alignment measurement unit to measure a relative positional deviation between the second shot area and the mold; controlling the substrate stage based on the global alignment information and the measured relative positional deviation so that the first shot area is positioned at an imprint position where the imprint processing is performed, and then starting the contact step; 1. An imprint apparatus comprising:

11. forming a pattern on a substrate by the imprint method according to any one of claims 1 to 9; processing the substrate on which the pattern is formed; and producing an article from the processed substrate.

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