IMPRINTING APPARATUS, METHOD OF CREATING DATA ON MATERIAL DISTRIBUTION, IMPRINTING METHOD, AND ARTICLE MANUFACTURING METHOD

Provided is an imprinting apparatus that forms patterns sequentially on a plurality of areas of a substrate by using a mold and imprint material. The apparatus includes a moving unit configured to be movable along a horizontal plane while carrying the substrate on which the imprint material is provided, and an applying unit configured to apply the imprint material onto the substrate based on information related to a state of the imprint material and information related to an order of pattern formation, the information related to the state of the imprint material varying with the movement of the moving unit.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an imprinting apparatus, a method of creating data on material distribution, an imprinting method, and an article manufacturing method.

2. Description of the Related Art

An imprinting method is known as a method of forming a microscopic pattern on a substrate so as to manufacture a semiconductor device or the like. In the imprinting method, imprint material (such as light-curable resin) is cast into a pattern that is formed on a substrate by using a mold having a relief pattern. If the substrate carrying the pattern is further processed in a state where a residual layer formed at the bottom of the pattern has significantly nonuniform thickness (in a state where the nonuniformity in the thickness of the residual layer is significant), a resulting article may fail to exhibit desired performance.

U.S. Patent Laid-Open No. 2007/0228593 has disclosed a method of reducing the nonuniformity in the thickness of the residual layer. Specifically, new data on the distribution of imprint material to be applied onto the substrate is created in accordance with the nonuniformity in the thickness of the residual layer that has been acquired by measuring the residual layer in a plurality of areas of the pattern formed of the imprint material. For example, a method of creating data on material distribution has been disclosed in which a larger amount of imprint material is applied to areas where the residual layer is expected to be thinner than in other areas.

SUMMARY OF THE INVENTION

The present inventors have found that the uniformity in the thickness of the residual layer is affected by the state of the imprint material that changes while the substrate carrying uncured imprint material moves along a horizontal plane. This aspect is not referred to in U.S. Patent Laid-Open No. 2007/0228593.

The present invention provides an imprinting apparatus, a method of creating data on material distribution, and an imprinting method in each of which data on a distribution of imprint material that reduces nonuniformity in the thickness of a residual layer is created.

According to an aspect of the present invention, there is provided an imprinting apparatus that forms patterns sequentially on a plurality of areas of a substrate by using a mold and imprint material. The apparatus includes a moving unit configured to be movable along a horizontal plane while carrying the substrate on which the imprint material is provided, and an applying unit configured to apply the imprint material onto the substrate based on information related to a state of the imprint material and information related to an order of pattern formation, the information related to the state of the imprint material varying with the movement of the moving unit.

DESCRIPTION OF THE EMBODIMENTS

First Embodiment

Configuration of Apparatus

FIG. 1illustrates an imprinting apparatus1according to a first embodiment of the present invention. Referring toFIG. 1, a substrate stage9carries a substrate3such as a wafer and moves along a horizontal plane. The term “horizontal plane” refers to a plane that is perpendicular to the direction of gravitational force. The phrase “to move along the horizontal plane” encompasses a case where the substrate stage9moves while inclining with respect to the horizontal plane by a small angle within a range of control error that may occur when the substrate stage9is driven. In the first embodiment, a term “information related to the state of imprint material” refers to likely nonuniformity in the thickness of a residual layer2b(seeFIGS. 6A to 6D) included in a pattern formed of imprint material that are estimated from the direction of movement of the substrate stage9(the information is hereinafter referred to as “likely residual-layer information”). The likely residual-layer information will be described later.

The imprinting apparatus1forms a relief pattern of ultraviolet-curable resin (imprint material)2by using a mold7and ultraviolet light4. A light source5is a device such as a halogen lamp or a light-emitting diode (LED) and emits the ultraviolet light4toward the substrate3. The light source5is provided vertically above (on the +Z side of) a mold stage6and applies the ultraviolet light4to the imprint material2on the substrate3through the mold7.

The mold stage6that holds the mold7on a side (−Z side) thereof facing the substrate3positions the mold7while holding the mold7. The mold7has a relief pattern in a central part8. While the first embodiment concerns a case where the mold7has a relief pattern covering one shot area20(seeFIGS. 3A and 3B), the mold7may have a relief pattern covering a plurality of shot areas20.

The substrate stage (moving unit)9that is movable while carrying the substrate3having the imprint material2applied (supplied) thereto is capable of positioning the substrate3in three axial directions including the direction in which the horizontal plane extends.

The mold stage6includes a coarse-adjustment stage10that coarsely adjusts the position of the mold7, a fine-adjustment stage11that finely adjusts the position of the mold7by units of a smaller length than the coarse-adjustment stage10does, and a holding portion12that holds the mold7, which are stacked in that order from the top. The mold7can be positioned in six axial directions by the coarse-adjustment stage10and the fine-adjustment stage11.

The coarse-adjustment stage10has an opening10ain a central part thereof. The fine-adjustment stage11has an opening11ain a central part thereof. The mold7is made of a material (such as quartz) that transmits the ultraviolet light4. Hence, the ultraviolet light4emitted from the light source5is transmitted through the mold7and falls onto the imprint material2on the substrate3. Note that a plate member (not illustrated) that transmits the ultraviolet light4is provided between the fine-adjustment stage11and the holding portion12.

The holding portion12is capable of holding the mold7by the use of a vacuum suction force or an electrostatic force. The holding portion12has an opening in a central part thereof in such a manner as to hold only a peripheral part of the relief pattern. The opening is provided between the mold7and the plate member, whereby a space13is provided.

A pressure-adjusting unit14communicates with the space13. The pressure-adjusting unit14includes a vacuum pump (not illustrated) and adjusts the pressure in the space13. To form a pattern on the substrate3, the shape of the mold7is changeable such that relevant parts of the mold7project or are depressed in the vertical direction.

In the following description, to bring the imprint material2on the substrate3and the mold7into contact with each other and fill the mold7having the relief pattern with the imprint material2(this process is hereinafter referred to as “imprinting”), the mold stage6is moved in the Z-axis direction. Alternatively, as long as imprinting is performable, at least one of the mold stage6and the substrate stage9may be moved in the Z-axis direction.

A dispenser (applying unit)15applies the imprint material2to a predetermined position of the substrate3while receiving the supply of imprint material2from a tank16that stores uncured imprint material2.FIG. 2is a bottom view of the dispenser15. The dispenser15has a line of ejection ports15A from which the imprint material2is ejected.

Each of the ejection ports15A ejects the imprint material2toward the substrate3by units of a predetermined amount (the unit is hereinafter defined as “drop”). The amount of ejection per drop ranges from subpicoliters to several picoliters. The dispenser15applies the imprint material2onto the substrate3along lines that are at intervals of several micrometers to dozens of micrometers. The dispenser15ejects an amount of imprint material2that is necessary for a single imprinting action on a single shot area20while the substrate3is moving below the dispenser15. Thus, uncured imprint material2(hereinafter simply referred to as “imprint material2”) is applied to a single shot area20.

The dispenser15applies the imprint material2to an area on the substrate3in accordance with an imprint-material-droplet pattern (data on the distribution of imprint material2) created by a creating unit18to be described later. The droplet pattern is also referred to as an application map or a drop recipe. The droplet pattern is data representing the droplet layout and the amount of imprint material2necessary in a single imprinting action (also referred to as “data on material distribution”). The data on material distribution is adjustable by increasing or decreasing at least one of the amount of imprint material2to be ejected and the number of positions of application of the imprint material2in a single imprinting action.

Referring now toFIG. 1, a control unit17includes a central processing unit (CPU), a random access memory (RAM), a hard disk drive (HDD), and so forth. The control unit17generally controls a series of operations of the imprinting apparatus1(hereinafter referred to as “imprinting process”) that are performed for forming a relief pattern made of the imprint material2. For example, the control unit17notifies the target position of the mold stage6and the target position of the substrate stage9, instructs the light source5to emit the ultraviolet light4toward the substrate3at a predetermined timing, reads a desired droplet pattern from a storage unit19storing different imprint-material-droplet patterns, transmits the droplet pattern to the dispenser15, and notifies the pressure-adjusting unit14of a target pressure to be generated during the imprinting process.

The storage unit19stores relief patterns prepared for the mold7, mold information related to the mold7of interest, and droplet patterns created by the below-described creating unit18. The storage unit19further stores dispenser information, imprinting-atmosphere information, information related to the direction of movement of the substrate stage9, information related to the order of imprinting in accordance with which imprinting is performed sequentially on a plurality of shot areas20of the substrate3(information related to the order of pattern formation; seeFIG. 3), and so forth.

The mold information is a set of pieces of information related to the mold7of interest and includes, for example, the line width, the density, and any defects of the relief pattern of the mold7, the number of times of performance of the imprinting process using a specific mold7, the number of times of performance of a cleansing process regarding a specific mold7, and so forth. The dispenser information is a set of pieces of information related to the dispenser15and includes, for example, the number of ejection ports15A of the dispenser15, the average amount of imprint material2ejected per ejection port15A, the actual amounts of imprint material2ejected from the respective ejection ports15A, the actual positions to which the imprint material2is ejected from the respective ejection ports15A, and so forth. The imprinting-atmosphere information is a set of pieces of information related to the imprinting process and includes, for example, the ambient temperature, the air current, and the oxygen concentration around the location where imprinting is performed, the kind of the imprint material2, the volatility of the imprint material2, and so forth.

The information related to the direction of movement of the substrate stage9represents the direction in which the substrate3to which the imprint material2has been applied moves from a position facing the dispenser15to a position facing the mold7(hereinafter referred to as “imprinting position”) where imprinting is to be performed. The storage unit19according to the first embodiment stores the likely residual-layer information that correlates with the information related to the direction of movement of the substrate stage9.

The storage unit19stores a program for creating a droplet pattern, which is summarized as a flow chart inFIG. 7, and a program for performing the imprinting process on all of the shot areas20of the substrate3, which is summarized as a flow chart inFIG. 9.

The creating unit18that creates a droplet pattern includes a CPU. When the creating unit18runs the program summarized inFIG. 7, a droplet pattern is created. The creating unit18creates a droplet pattern on the basis of the mold information, the dispenser information, and the likely residual-layer information.

Now, how the substrate stage9moves will be described with reference toFIGS. 3A, 3B, 4, 5A to 5F, and 6A to 6D.FIGS. 3A and 3Beach illustrate an order of imprinting. The imprinting apparatus1forms patterns sequentially on a plurality of shot areas (a plurality of areas)20, which are objects of pattern formation, respectively. The numbers in parentheses given in the respective shot areas20represent the order of imprinting. Specifically, in the case illustrated inFIG. 3A, patterns start to be formed on shot areas20in the first row sequentially in the +X direction, and then on shot areas20in the second row sequentially in the +X direction.

In the case illustrated inFIG. 3B, patterns start to be formed on shot areas20in the first row sequentially in the +X direction, and then on shot areas20in the second row sequentially in the −X direction. After the completion of every imprinting action of forming a pattern on a single shot area20, the substrate stage9moves from the imprinting position to the position facing the dispenser15.

A relationship between the direction of movement of the substrate stage9and the likely residual-layer information will now be described. The substrate stage9is positioned with a delay in response to a control command (a command that indicates the target position with respect to time) issued thereto. In the graph illustrated inFIG. 4, the horizontal axis represents time, and the vertical axis represents the position of the substrate stage9for the solid line and the positional deviation of the substrate stage9from the instructed position (the positional error of the substrate stage9with respect to the instructed position) for the dotted line. For example, the graph shows that, even if the substrate stage9is instructed to start to move at time t1and to stop at time t2, the substrate stage9is not stabilized at time t2but the positional deviation of the substrate stage9falls into a permissible range of deviation at time t3.

FIGS. 5A to 5Fillustrate the direction of movement of the substrate stage9and the inclination of the substrate stage9.FIGS. 5A and 5Deach illustrate a state of the substrate stage9during a period from time t1to time t2.FIGS. 5B and 5Eeach illustrate a state of the substrate stage9during a period from time t2to time t3.FIGS. 5C and 5Feach illustrate a state of the substrate stage9after time t3. As illustrated inFIGS. 5B and 5E, the substrate stage9moving in the +X direction tends to incline slightly such that the +X side thereof is positioned lower than the other side thereof, and the substrate stage9moving in the −X direction tends to incline slightly such that the −X side thereof is positioned lower than the other side thereof.

In the first embodiment, the control unit17puts the priority on the throughput and controls the mold stage6such that imprinting is performed during the period from time t2to time t3. In such a case, if the creating unit18does not create any droplet pattern by using the below-described method, the imprint material2and the mold7are brought into contact with each other while the substrate3is inclined downward on the leading side (seeFIG. 6A or 6B). Consequently, a residual layer2bwhose thickness is significantly nonuniform is formed at the bottom of patterned imprint material2a(hereinafter referred to as “imprint-material pattern2a”; seeFIG. 6C or 6D). The residual layer2brefers to a layer of imprint material2that is formed at the bottom (in the valleys) of the imprint-material pattern2ain the imprinting process.

The information related to the direction of movement of the substrate stage9that is used in the first embodiment is the direction in which the substrate stage9moves from the position facing the dispenser15to the position where imprinting is performed. That is, in the case of the imprinting apparatus1, the direction of movement of the substrate stage9is the +X direction. The likely residual-layer information according to the first embodiment is the information indicating that the residual layer2bis likely to be thicker on the leading side (+X side) than on the trailing side (−X side) that is opposite the leading side in a single shot area20(seeFIGS. 5A to 5F and 6A to 6D). The trailing side is opposite the leading side.

(Method of Creating Droplet Pattern)

A method100of creating a droplet pattern according to the first embodiment will now be described with reference toFIG. 7. The method100is performed for reducing the variation in the thickness of the residual layer2b, i.e., the nonuniformity in the thickness of the residual layer2b. That is, a droplet pattern with which the nonuniformity in the thickness of the residual layer2bincluded in the resulting pattern that may occur in accordance with the direction of movement of the substrate stage9is reduced is created.

FIG. 7is a flow chart illustrating the method100of creating a droplet pattern. In step S101, the creating unit18acquires pieces of information necessary in creating a droplet pattern: namely, the mold information, the dispenser information, the imprinting-atmosphere information, and so forth. In step S102, the creating unit18creates data on the distribution of imprint material2, which is an estimation of the required amount of imprint material2for each of sections of a single shot area20, on the basis of the pieces of information acquired in step S101.

In step S103, the creating unit18calculates the number of droplets of imprint material2that is required for a single imprinting action from information indicating the size of each droplet ejected from the dispenser15. In step S104, the calculated number of droplets are roughly allocated among the sections of the shot area20, whereby a preliminary droplet pattern is created. An example of the preliminary droplet pattern is illustrated inFIG. 8A. The area illustrated inFIG. 8Acorresponds to a single shot area20. Blank rectangular sections21correspond to sections where no imprint material2is to be applied. Black rectangular sections22correspond to sections where the imprint material2is to be applied.

Referring toFIG. 7, in step S105, the creating unit18acquires the information related to the direction of movement of the substrate stage9and the likely residual-layer information corresponding to the information related to the direction of movement of the substrate stage9from the storage unit19. In step S106, the creating unit18creates a droplet pattern to be set on the dispenser15from the likely residual-layer information and the preliminary droplet pattern that have been acquired in steps S104and S105. The droplet pattern created in step S106is composed of the same number of droplets of imprint material2as the preliminary droplet pattern, but the droplets are distributed in a different way. In step S107, the creating unit18stores the droplet pattern that have been acquired in step S106to the storage unit19.

For example, the creating unit18creates a droplet pattern illustrated inFIG. 8B. In this droplet pattern, the density of the imprint material2to be applied (hereinafter also referred to as “application density”) on the leading side (a side nearer to the destination) on which the residual layer2btends to be thick is made lower than the density of the imprint material2to be applied on the trailing side (a side farther from the destination) on which the residual layer2btends to be thin. If the imprint material2is applied on the basis of the droplet pattern created in step S106, the nonuniformity in the thickness of the residual layer2bincluded in the resulting pattern is reduced. The term “application density” refers to the amount of imprint material2per unit area. The application density is adjustable by increasing or decreasing at least one of the amount of imprint material2to be ejected from the dispenser15in a single ejecting action (the amount of imprint material2per droplet) and the number of points to which the imprint material2is to be applied.

If the dispenser15is on the +X side with respect to the mold7and the substrate3having the imprint material2moves in the −X direction toward the imprinting position, another droplet pattern is created.FIG. 8Cillustrates an exemplary droplet pattern created in the case where the substrate stage9moves in the −X direction. In the case where the substrate stage9moves in the −X direction also, a droplet pattern is created such that the density of the imprint material2to be applied on the leading side on which the residual layer2btends to be thick becomes lower than the density of the imprint material2to be applied on the trailing side on which the residual layer2btends to be thin.

The creating unit18creates a plurality of droplet patterns for one kind of mold information. The reason for this is as follows. Occasionally, in the imprinting process, part of the relief pattern of the mold7may protrude from the substrate3. Therefore, a droplet pattern with which the imprint material2is prevented from being ejected toward such protruding part of the relief pattern also needs to be created.

A flow of the imprinting process will now be described with reference toFIGS. 9 and 10A to 10E.FIG. 9is a flow chart illustrating a program of the imprinting process.FIGS. 10A to 10Eillustrate steps of the imprinting process. When the control unit17runs the program illustrated inFIG. 9, the imprinting process is performed.

First, in step S100, the creating unit18creates a droplet pattern in accordance with the method100described above. In step S200, a conveying mechanism (not illustrated) mounts the mold7having a desired relief pattern onto the mold stage6.

In step S300, the control unit17acquires the mold information related to the mold7of interest and acquires a set of droplet patterns corresponding to that mold7. The control unit17selects a shot area20on which a pattern is to be formed, and sets one of the droplet patterns that corresponds to the direction of movement of the substrate stage9in that shot area20on the dispenser15.

In step S400, the dispenser15applies uncured imprint material2onto the substrate3in accordance with the droplet pattern that has been set as above (seeFIG. 10A). In step S500, when the substrate3has moved from the position facing the dispenser15to the imprinting position, the mold7is pressed into the imprint material2at a predetermined timing (seeFIG. 10B). The predetermined timing refers to a point of time (between time t2and time t3) before the positional deviation of the substrate stage9falls into the permissible range.

In step S600, after the recesses of the mold7are filled with the imprint material2(seeFIG. 10C), the light source5emits the ultraviolet light4for over a predetermined period of time, whereby the imprint material2, which has not been cured, is cured (seeFIG. 10D). In step S700, the mold stage6removes the mold7(seeFIG. 10E). Thus, an imprint-material pattern2ais formed on the substrate3.

The droplet pattern created by the creating unit18is based on the likely residual-layer information. Since the dispenser15applies the imprint material2in accordance with the droplet pattern created for reducing the nonuniformity in the thickness of the residual layer2b, the thickness of the residual layer2bof the imprint-material pattern2abecomes substantially uniform. In step S800, the control unit17checks if all of the shot areas20of the substrate3have been provided with respective patterns. If so (YES), the process proceeds to step S1000, in which the control unit17allows the substrate3to be carried out.

If there are any shot areas20provided with no patterns (NO), the process proceeds to step S900, in which the control unit17selects one of such shot areas20and checks if the droplet pattern needs to be changed in performing imprinting on that shot area20.

The droplet pattern needs to be changed if, for example, the direction of movement of the substrate stage9in a shot area20that is to be subjected to imprinting next is different from the direction of movement of the substrate stage9in another shot area20that has been subjected to imprinting last time or if part of the relief pattern of the mold7protrudes from the substrate3during the imprinting process. If the droplet pattern needs to be changed, the process returns to step S300, in which another appropriate droplet pattern is selected. Then, steps S400to S900are performed again. If the droplet pattern does not need to be changed, steps S400to S900are performed with the same droplet pattern. Regarding the next substrate3and substrates3included in the next lot also, patterns are formed on the basis of appropriate droplet patterns selected by the control unit17.

The droplet pattern may be reselected after patterns are formed on a predetermined number of shot areas20or after a single substrate3is processed, by acquiring information related to any defective-pattern inspection or any information related to irregular-pattern detection from the inside or the outside of the imprinting apparatus1. Alternatively, a brand new droplet pattern may be created. The defective-pattern information refers to the result of any measurement of the accuracy in the transfer of the pattern made of the imprint material2and is acquired by an inspection device (not illustrated). The information related to irregular-pattern detection includes pieces of information indicating any irregularity in the accuracy of arrangement of droplets ejected by the dispenser15, any irregularity in the force of pressing or releasing the mold7, the presence of any impurities taken in during the imprinting process, the exceeding of a predetermined number of times of use of the mold7, and so forth.

As described above, in the first embodiment, the creating unit18creates a droplet pattern on the basis of the information related to the direction of horizontal movement of the substrate stage9and the likely residual-layer information that correlates with the information related to the direction of movement of the substrate stage9. Then, the dispenser15applies the imprint material2in accordance with the droplet pattern created by the creating unit18. Even if the priority is put on the throughput and imprinting is performed before the substrate3is stabilized, the nonuniformity in the thickness of the residual layer2bof the imprint-material pattern2acan be made lower (the uniformity in the thickness of the residual layer2bcan be made higher) than in a case where the first embodiment is not applied.

The likely residual-layer information is stored in advance in the storage unit19. Therefore, even if the substrate stage9moves in a new direction to the imprinting position, the creating unit18can create a droplet pattern that reduces the nonuniformity in the thickness of the residual layer2bwithout the performance of the measurement of the thickness of the residual layer2b. Hence, at least a period of time that may be consumed for the first measurement of the thickness of the residual layer2bat the beginning of the imprinting process can be saved.

If the substrate3having the imprint material2and moving away from the position facing the dispenser15moves to the imprinting position without taking the shortest route, the information related to the direction of movement of the substrate stage9may indicate a direction in which the substrate stage9moves from a position of the last stop to the imprinting position.

Second Embodiment

The inclination of the substrate stage9at the imprinting position varies with the speed of the substrate stage9. In a second embodiment of the present invention, the creating unit18creates droplet patterns with different levels of nonuniformity in the application density on the basis of the direction of movement of the substrate stage9, the likely residual-layer information estimated from the direction of movement of the substrate stage9, and information related to the speed at which the substrate stage9moves along the horizontal plane.

The information related to the speed of the substrate stage9is information indicating the level of the speed or the rate of acceleration or the like of the substrate stage9. Creating droplet patterns on the basis of such information related to the speed of the substrate stage9provides a residual layer2bhaving substantially uniform thickness, even if the inclination of the substrate stage9at the imprinting position varies with the speed of the substrate stage9.

In step S105of the flow chart illustrated inFIG. 7described in the first embodiment, the creating unit18according to the second embodiment acquires the information related to the speed of the substrate stage9as well, and creates a droplet pattern on the basis of those pieces of information. For example, in a droplet pattern created for the substrate stage9moving fast, the application density varies wider among areas of the substrate3than in a droplet pattern created for the substrate stage9moving more slowly.

Third Embodiment

Information related to the state of the imprint material2according to a third embodiment of the present invention corresponds to the likely residual-layer information or may indicate the state of the imprint material2that correlates with the likely residual-layer information and that is observed while the substrate stage9is moving. For example, the information related to the state of the imprint material2indicates the way the volume of each of the droplets applied to the substrate3changes because of volatilization.

Information related to the order of pattern formation according to the third embodiment corresponds to the order of imprinting: that is, as illustrated inFIGS. 3A and 3B, information indicating in what ordinal number each of the shot areas20undergoes pattern formation. The information related to the order of pattern formation may indicate the order of imprinting in a case where patterns are formed on a plurality of shot areas23in a single imprinting action.

In the imprinting apparatus1according to the third embodiment, the creating unit18creates droplet a pattern on the basis of the order of imprinting and the likely residual-layer information. Even if the direction of movement of the substrate stage9from the position facing the dispenser15to the imprinting position is constant, the state of the residual layer2bmay be affected by factors such as the air current in the imprinting apparatus1or the air current occurring with the movement of the substrate stage9. The third embodiment is advantageous in a case where the state of the residual layer2bis not constant because of the difference in the order of imprinting.

FIG. 11illustrates a relationship between the order of imprinting and the likely residual-layer information in a case where the imprint-material pattern2ais formed in the order of imprinting that is illustrated inFIG. 3B. The size of circles drawn in each of a plurality of shot areas20corresponds to the thickness of the residual layer2b. Specifically, the larger the circle, the thicker the residual layer2b.

FIGS. 12A and 12Beach illustrate a relationship between the order of imprinting and the state of pattern formation. A shot area23(a first area) has the imprint material2but is yet to undergo pattern formation. On the other hand, shot areas24(second areas) each have an imprint-material pattern2a. InFIGS. 12A and 12B, the states of the droplets of imprint material2on the shot area23have changed because of volatilization that has occurred while the substrate stage9has been moving.

Referring toFIG. 11, in the first row, patterns are formed sequentially toward the leading side (+X side) of the substrate stage9. That is, as illustrated inFIG. 12A, the substrate stage9moves with the shot area23being on the leading side of the substrate stage9with respect to the shot areas24. In this case, the likely residual-layer information indicates that the residual layer2btends to be thicker on the leading side of the substrate stage9than on the trailing side opposite the leading side.

Referring toFIG. 11, in the second row, patterns are formed sequentially toward the trailing side (the −X side) opposite the leading side. That is, as illustrated inFIG. 12B, the substrate stage9moves with the shot areas24being on the leading side of the substrate stage9with respect to the shot area23. In this case, the likely residual-layer information indicates that the residual layer2btends to be thinner on the leading side of the substrate stage9than on the trailing side opposite the leading side.

Now, the imprinting apparatus1according to the third embodiment will be described. The storage unit19according to the third embodiment stores the order of imprinting, and the likely residual-layer information that correlates with the order of imprinting. The likely residual-layer information according to the third embodiment indicates the tendency of the nonuniformity in the thickness of the residual layer2bthat is estimated from the order of imprinting and the direction of movement of the substrate stage9. In the third embodiment, imprinting is performed in a state where the substrate stage9has been stabilized with the positional deviation thereof being within the permissible range. The imprinting process performed in the third embodiment is the same as that described in the first embodiment, except the method of creating a droplet pattern by the creating unit18. Therefore, redundant description is omitted.

The creating unit18creates a droplet pattern in accordance with the order of imprinting (information that correlates with the state of the imprint material2and that varies with the movement of the moving unit) and the likely residual-layer information that correlates with the order of imprinting.

A case where patterns are formed sequentially toward the leading side of the substrate stage9as in the case of the first row illustrated inFIG. 11will now be described. The creating unit18creates a droplet pattern with which the imprint material2can be applied to the shot area23such that the density of the imprint material2becomes lower on the leading side on which the residual layer2btends to be thick than on the trailing side on which the residual layer2btends to be thin (seeFIG. 8B). In other words, the creating unit18creates a droplet pattern (second data) such that, in the state where the shot area23is on the trailing side of the substrate stage9with respect to the shot areas24, the density of the imprint material2applied on the leading side becomes lower than the density of the imprint material2applied on the trailing side.

A case where patterns are formed sequentially toward the trailing side of the substrate stage9as in the case of the second row illustrated inFIG. 11will now be described. The creating unit18creates a droplet pattern (first data; seeFIG. 13) with which the imprint material2can be applied to the shot area23such that the density of the imprint material2becomes higher on the leading side on which the residual layer2btends to be thin than on the trailing side on which the residual layer2btends to be thick. In other words, the creating unit18creates a droplet pattern such that, in the state where the shot area23is on the leading side of the substrate stage9with respect to the shot areas24, the density of the imprint material2applied on the leading side becomes higher than the density of the imprint material2applied on the trailing side.

Since the creating unit18creates a droplet pattern on the basis of the order of imprinting and the likely residual-layer information, a droplet pattern that reduces the nonuniformity in the thickness of the residual layer2bcan be created even if the likely state of the residual layer2bvaries with the order of imprinting.

The information related to the order of pattern formation only needs to be information that clarifies the positional relationship between the shot area23and the shot areas24. That is, any information other than the information related to the order of imprinting may also be taken.

For example, comparing the position of a shot area20on which a pattern has been formed in an n-th order and the position of a shot area20on which a pattern is to be formed in an n+1-th order, information indicating whether or not the direction from the shot area20on which the pattern has been formed in the n-th order toward the shot area20on which the pattern is to be formed in the n+1-th order is the same as the direction of movement of the substrate stage9(information related to the positional relationship between patterns that are formed successively) may be taken. Alternatively, information indicating whether or not the shot areas24are present on the leading side of the substrate stage9(information indicating the presence of the second area on the leading side with respect to the first area) may be taken. Alternatively, information indicating where in the XY plane the shot areas24are present (information related to the position of the second area) may be taken.

Alternatively, the creating unit18may create a droplet pattern on the basis of the position of a member (not illustrated) that supplies inert gas to an area around the imprinting position so as to push away the ambient air. Alternatively, the creating unit18may create a droplet pattern on the basis of the distance and the direction of movement of the substrate stage9up to the imprinting position. As in the second embodiment, the creating unit18may create a droplet pattern on the basis of information related to the speed of the substrate stage9. The order of imprinting is not limited to those illustrated inFIGS. 3A and 3B. Imprinting may be performed in a random order, a zigzag order, or the like.

Other Embodiments

Other embodiments of the present invention will now be described.

The imprinting apparatus1may include a plurality of dispensers15. In that case, the direction from the position facing any of the dispensers15that has ejected the imprint material2to a shot area20of interest toward the imprinting position is regarded as the direction of movement of the substrate stage9. The creating unit18creates a suitable droplet pattern on the basis of the likely residual-layer information related to the imprint-material pattern2athat is acquired from information related to different movements of the substrate stage9that are based on the different dispensers15.

Since different dispensers15are used in accordance with the position of the shot area23of the substrate3, the number of pieces of likely residual-layer information increases. Even in such a case, both the nonuniformity in the thickness of the residual layer2bin a single shot area20and the nonuniformity in the thickness of the residual layer2bamong a plurality of shot areas20can be reduced.

The direction of movement of the substrate stage9is identified by the position of the shot area20of interest on the substrate3, the position of the dispenser15, and the imprinting position. The direction of movement of the substrate stage9may be identified by the creating unit18from the foregoing pieces of information, or may be calculated by the control unit17and be stored in the storage unit19so as to be used later.

The creating unit18may be provided on the outside of the imprinting apparatus1. The data on the droplet pattern that is created by the creating unit18may be supplied to the storage unit19through an information-storage medium or over wired or wireless communications. The control unit17, the storage unit19, and the creating unit18may be all provided on a single control board or on separate control boards, as long as the units17,18, and19have the respective functions described above.

To reduce the nonuniformity in the thickness of the residual layer2b, the method of creating a droplet pattern according to each of the first to third embodiments may be combined with a method of adjusting the inclination of the mold7. In that case, when the inclination of the mold7is changed, the creating unit18changes the nonuniformity in the application density of the imprint material2in the droplet pattern.

While the first to third embodiments each concern an optical imprinting method in which the imprint material2, which is curable with light, is cured with the application of the ultraviolet light4thereto, the present invention is not limited to such an imprinting method. The imprint material2may be a material that is curable with any kind of electromagnetic radiation including light, or a material that is curable with heat.

Article Manufacturing Method

A method of manufacturing an article (a semiconductor integrated-circuit device, a liquid-crystal-display device, an imaging device, a magnetic head, a compact disc rewritable (CD-RW), an optical device, a photomask, or the like) according to an embodiment of the present invention includes a step of forming a pattern on a substrate3(a monocrystalline silicon wafer, a silicon on insulator (SOI), a glass plate, or the like) by using the imprinting apparatus1, and a step of performing at least one of etching and ion implantation on the substrate3having the pattern. The method may further include any known processing steps (oxidization, film formation, deposition, planarization, resist stripping, dicing, bonding, packaging, and so forth).

This application claims the benefit of Japanese Patent Application No. 2015-074495, filed Mar. 31, 2015, which is hereby incorporated by reference herein in its entirety.