IMPRINT APPARATUS, IMPRINT METHOD, AND ARTICLE MANUFACTURING METHOD

Provided is an imprint apparatus that brings a mold into contact with an imprint material on a substrate to perform patterning on the substrate, and includes a mold holder configured to hold the mold; a substrate holder configured to hold the substrate; a driving device configured to move at least one of the mold holder and the substrate holder; a detector configured to detect a state of the driving device; and a controller configured to perform decision that release of the mold is started based on an output of the detector and to control the driving device so as to decrease a force for the release by the driving device in accordance with the decision.

BACKGROUND OF THE INVENTION

1. Field of the Invention

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

2. Description of the Related Art

There is a microfabrication technology that forms a pattern on a substrate by imprint processing for molding an imprint material on the substrate with use of a mold. This technology is also referred to as an “imprint technology”, by which a pattern (structure) with dimensions of a few nanometers can be formed on a substrate. One example of imprint technologies includes a photo-imprint method. An imprint apparatus employing the photo-imprint method first supplies a photo-curable material (resin) to a shot area on a substrate. Next, the imprint material on the substrate is molded with use of a mold. After the imprint material is irradiated with light for curing, the cured imprint material is released from the mold, whereby a pattern is formed on the substrate. Imprint technologies include not only the photo-imprint method but also the thermal imprint method with use of a thermoplastic material (resin) or the like.

In regard to the improvement in throughput of the imprint apparatus, an increase in speed in mold-releasing is also effective. Japanese Patent Laid-Open No. 2007-81048 discloses an imprint apparatus that detects the timing at which the mold releasing is started with use of an optical sensor, temporarily stops the mold-releasing operation once the mold-releasing is started to wait for the sufficient progress of the mold-releasing, and then completes the mold-releasing at a high speed. In this manner, both the decrease in occurrence of a pattern defect and a greater throughput can be achieved.

Here, the timing at which the mold-releasing is started and the magnitude of the mold-releasing force to be applied at that time exhibit poor reproducibility and are highly likely to vary from time to time. Thus, if an attempt is made by the technology as disclosed in Japanese Patent Laid-Open No. 2007-81048 to reduce such variation by the temporal stop of the mold-releasing operation before and after the start of mold-releasing, there is a limitation in improvement in throughput. On the other hand, it is also contemplated that a greater mold-releasing force is applied for a short time to achieve greater throughput, which however results in further reduction in reproducibility. The mold-releasing force and the reaction force are balanced from the start of applying the mold-releasing force to the start of mold-releasing, so that both the substrate stage and the mold holding mechanism are substantially stationary. Once the mold-releasing is started, the reaction force is rapidly decreased. Thus, an abrupt change may occur at the position of the substrate stage. The mold-releasing force may reach to, for example, about 100 N. Hence, if the mold-releasing force is not quickly decreased with a decrease in the reaction force, the mold-releasing force that is greater than necessary is applied to a pattern or a mold, resulting in the occurrence of a defect therein.

SUMMARY OF THE INVENTION

The present invention provides, for example, an imprint apparatus which is advantageous in terms of compatibility between accurate patterning and throughput.

According to an aspect of the present invention, an imprint apparatus that brings a mold into contact with an imprint material on a substrate to perform patterning is provided that includes a mold holder configured to hold the mold; a substrate holder configured to hold the substrate; a driving device configured to move at least one of the mold holder and the substrate holder; a detector configured to detect a state of the driving device; and a controller configured to perform decision that release of the mold is started based on an output of the detector and to control the driving device so as to decrease a force for the release by the driving device in accordance with the decision.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, a description will be given of a vibration type actuator according to an embodiment of the present invention with reference to the drawings.

First Embodiment

First, a description will be given of an imprint apparatus according to a first embodiment of the present invention.FIG. 1is a schematic view illustrating a configuration of an imprint apparatus100according to the present embodiment. The imprint apparatus100is used to manufacture a semiconductor device, etc. as an article, brings an uncured resin (imprint material)20coated on a substrate21into contact with a mold10, and forms a pattern to the resin20on the substrate21. Note that the imprint apparatus100is intended to employ a photo-imprint method as an example. In the following drawings, a description will be given where the Z axis is aligned in the up and down direction (vertical direction) and mutually orthogonal axes X and Y are aligned in a plane perpendicular to the Z axis. The imprint apparatus100includes an illumination system (not shown), a mold holding mechanism (mold holder)1, a substrate stage (substrate holder)2, a dispenser (not shown), and a controller4.

The illumination system is a resin curing unit that irradiates the mold10with ultraviolet light emitted from a light source by adjusting the ultraviolet light to light suitable for curing the resin20. The light source may be any light source as long as it emits not only ultraviolet light but also light having a wavelength that transmits through the mold10and cures the resin20. For example, when a thermal-curing method is employed, a heating unit for curing a thermosetting resin is disposed instead of the illumination system as a resin curing unit in the vicinity of the substrate stage2.

The mold10is a mold that has a rectangular planar shape and has a concave-convex pattern, such as a three-dimensionally formed circuit pattern or the like, formed at the central portion of the surface opposite to the substrate21. As the material of the mold10, any ultraviolet light transmissive material such as quartz may be employed.

The mold holding mechanism (mold holder)1has a mold chuck11for holding the mold10, a mold driving mechanism (driving device)14for supporting and moving the mold chuck11, and a flexure12. The mold chuck11holds the mold10by suctioning or attracting the outer peripheral area of the surface of the mold10to be irradiated with ultraviolet light using a vacuum suction force or an electrostatic force. Also, each of the mold chuck11and the mold driving mechanism14has an aperture area at the central portion (the inside thereof) such that ultraviolet light emitted from the illumination system is directed toward the substrate21by passing through the mold10. The mold driving mechanism14moves the mold10when the mold10is roughly aligned with the substrate21in the Z-axial direction at the time of bringing them into contact with each other or retracts the mold10during the attaching/detaching operations of the mold10or at an abnormal time. The flexure12is warped when the load is applied on the mold10by bringing the mold10into contact with the substrate21so as to conform the mold10to the surface of the substrate21. The mold chuck11is connected to a supporting table13via the flexure12. The supporting table13is connected to a main body31via the mold driving mechanism14. The main body31is mounted on a surface plate33via a mount32for vibration insulation.

The mold holding mechanism1further generates a force (load, physical quantity) to be applied to the mold10i.e., a mold-releasing force and has a force sensor (detector)15that, detects a quantity (state) relating to the driving of a fine movement stage22for receiving a reaction force. In other words, the state refers to a force acting on at least one of the mold holding mechanism1and the substrate stage2. As the force sensor15, a load cell, a strain gauge, a piezoelectric element, or the like may be employed. For example, when a strain gauge is employed as the force sensor15, the strain gauge is attached to the flexure12to detect a bending of the flexure12. Here, in order for the force sensor15to detect a force to be applied to the mold10upon releasing the mold10from the resin20on the substrate21, the force sensor15needs to be configured such that it can detect a force in the Z-axial direction (releasing direction). At least six force sensors15need to be arranged for detecting a force in six axial directions as a whole.

The substrate21is a wafer consisting of, for example, single crystal silicon. For use in the manufacture of articles other than semiconductor devices, as the material of the substrate21, an optical glass such as quartz may be employed for an optical element and GaN, SiC or the like may be employed for a light-emitting element.

The substrate stage (substrate holder)2is movable while holding the substrate21. The substrate stage2aligns the mold10with the substrate21and moves the substrate21in the Z-axial direction so as to selectively bring the mold10into contact with the resin20on the substrate21or release the mold10from the resin20. The substrate stage2includes a fine movement stage22and a coarse movement stage24. The fine movement stage22includes a top plate on which the substrate21is placed and at least six linear motors (driving devices)23capable of performing positioning in six degrees of freedom. Note that an electromagnet or the like may also be used instead of a linear motor. The fine movement stage22is supported in a non-contact by the driving force of the linear motor23, and thus, can be positioned with high accuracy. The position of the fine movement stage22is detected with use of a laser interferometer (detector)25on the main body31. As the position detector, an encoder or the like may also be used instead of the laser interferometer25. The controller4can also determine a relative displacement between the fine movement stage22and the mold10by simultaneously causing the laser interferometer25to detect the position of the mold10or the mold chuck11and taking a difference between the position of the mold10or the mold chuck11and the position detection value of the fine movement stage22. In this manner, even if the position of the mold10varies, the fine movement stage22can be accurately aligned with the mold10. On the other hand, the coarse movement stage24mounts the fine movement stage22in a non-contact via the linear motor23, and can move a multiphase type linear motor (actuator) (not shown) capable of long-distance driving in the X-Y axial directions which are the combination of the X- and Y-axial directions. As the actuator, a plane motor which is movable in the X- and Y-axial directions may be used instead of a multiphase type linear motor. The coarse movement stage24can move the transfer position, at which the concave-convex pattern is to be transferred onto the substrate21, directly below the mold10.

The dispenser applies the uncured resin20to a shot area (pattern forming area) preset on the substrate21with a desired application pattern. The resin20serving as the imprint material needs to have fluidity when it is filled between the mold10and the substrate21but to be solid for retaining its shape after being molded. In particular, in the present embodiment, the resin20is an ultraviolet light curable resin (photocurable resin) that exhibits curing properties to such a degree that when exposed to ultraviolet light, but a thermosetting resin, a thermoplastic resin, or the like may also be employed instead of a photocurable resin depending on various conditions such as article manufacturing processes.

The controller4is constituted by, for example, a computer or the like and is connected to the components of the imprint apparatus100through a line so as to control the operations and adjustment of the components by a program or the like. In particular, in the present embodiment, the controller4may execute control in the mold-releasing step as shown in the following. Note that the controller4may be integrated with the rest of the imprint apparatus100(provided in a shared housing) or may be provided separately from the rest of the imprint apparatus100(provided in a separate housing).

Next, a description will be given of the basic flow of imprint processing (imprint method) performed by the imprint apparatus100. First, the controller4causes the dispenser to apply the resin20to a predetermined shot area on the substrate21, and then places the substrate21on the substrate stage2so as to position the transfer position for each shot area, at which the concave-convex pattern is to be transferred onto the substrate21, directly below the mold10(positioning step). Next, the controller4drives at least one of the linear motor23and the mold driving mechanism14to move at least one of the mold holding mechanism (mold holder)1and the substrate stage (substrate holder)2. In this manner, the substrate21and the mold10can be approximated to a predetermined interval (e.g., a few nm to 100 nm) (contacting step). Then, the resin20on the substrate21is filled into the mold10in accordance with the concave-convex pattern shape thereof. At this time, the controller4needs to control the posture of the substrate stage2so as to make an interval between the substrate21and the mold10uniform. Next, the controller4causes the illumination system to illuminate ultraviolet light on the resin20to cure (curing step). Then, as in the contacting step, the controller4moves at least one of the mold holding mechanism (mold holder)1and the substrate stage (substrate holder)2and stretches an interval between the substrate21and the mold10to release the mold10from the cured resin20(mold-releasing step).

Next, a description will be given of control in the mold-releasing step in the present embodiment. First, as a Comparative Example, a description will be given of the relationship of forces applied to the components in the mold-releasing step when the present invention is not applied.FIG. 7is a graph illustrating changes in a force detection value and a command value in the Z-axial direction in the mold-releasing step in a Comparative Example, where a time is plotted on the horizontal axis. In the stage of the curing step, the mold driving mechanism14is driven to generate an imprint force for pressing the mold10toward the negative side in the Z-axial direction. The reason for this is to promote the resin20to be filled in the concave-convex pattern of the mold10. At this time, the fine movement stage22receives a force directed toward the negative side in the Z-axial direction and the linear motor23generates a force directed toward the positive side in the Z-axial direction for overcoming the negative side force. When the process shifts to the mold-releasing step (T1) after completion of the curing step, the mold driving mechanism14is driven to generate a mold-releasing force for peeling the mold10toward the positive side in the Z-axial direction. At this time, the fine movement stage22receives a force directed toward the positive side in the Z-axial direction and the linear motor23generates a force directed toward the negative side in the Z-axial direction for overcoming the positive side force. The mold-releasing force needs to be appropriately generated at the transfer position on the substrate21. When the transfer position particularly changes, the positional relationship between the linear motor23and the transfer position changes, and thus, the controller4changes the distribution ratio between forces generated by the individual linear motors23depending on the transfer position. The mold10receives the force generated by the linear motor23via the resin20, but the force received by the mold10is supported by the mechanism of the components constituting the mold holding mechanism1and the driving force of the mold driving mechanism14, so that the position of the mold10is maintained. On the other hand, the fine movement stage22receives a reaction force from the mold holding mechanism1via the resin20, but the force generated by the linear motor23and the reaction force are balanced, so that the position of the fine movement stage22is also maintained. Next, if the force generated by the linear motor23exceeds a bonding force between the resin20and the mold10, the resin20and the mold10are peeled off therefore the mold-releasing is started (T2). The reaction force generated via the resin20rapidly decreases upon start of the mold-releasing, but the reaction force becomes zero upon completion of the mold-releasing (T3).

However, the reproducibility of the timing of start of the mold-releasing (T2) may not be obtained or feedback control may fail to meet the timing of start of the mold-releasing as shown in the command value to be given to the linear motor23inFIG. 7. In this case, the mold-releasing force may be continuously applied in spite of the fact that the mold-releasing force actually becomes unnecessary after completion in the mold-releasing or the displacement of the fine movement stage22may remain, which may result in damaging the concave-convex pattern formed on the mold10. Thus, in the present embodiment, the controller4executes the following control in the mold-releasing step.

FIG. 2is a block diagram illustrating an exemplary control system relating to the fine movement stage22in the controller4in the present embodiment. A position detection value output from the laser interferometer25is converted into an orthogonal coordinate system of X, Y, θz, Z, θx, and θy by a coordinate converter42. A position controller (position controlling unit)41includes a PID controller, a filtering unit, a limiting unit, and the like and generates a command value for each axis based on a difference between a position target value and a position detection value. Each command value is converted by the thrust force distribution43into a command value for each linear motor23and then is output to each linear motor23to drive the fine movement stage22. A force command generating unit44generates a force command required for mold-releasing. A command converting unit45converts a force command into a corresponding position target value. Note that the control system illustrated inFIG. 2is a position control system but may also be switched to a force control system in the curing step and the mold-releasing step.

FIG. 3is a block diagram illustrating an exemplary configuration of a force command generating unit44. The force command generating unit44holds a first force command waveform (first waveform) and a second force command waveform (second waveform), and outputs a force command (command value) based on any one of the force command waveforms. Here, both the first force command waveform and the second force command waveform have a shape to cancel out (reduce) a reaction force received by the fine movement stage22. Among them, the first force command waveform is a waveform that increases the absolute value of the force directed toward the mold-releasing direction with time. Note that the first force command waveform may be a waveform that partially decreases the absolute value as long as it increases as a whole. On the other hand, the second force command waveform is a waveform that decreases the absolute value of the force directed toward the mold-releasing direction with time. Note that the second force command waveform may be a waveform that partially increases the absolute value as long as it decreases as a whole. A force waveform analyzer441first performs decision of start of the mold-releasing based on a detection value output from the force sensor15. In this case, the detection value is a value of a force serving as a physical quantity used for the decision of start of the mold-releasing. The force waveform analyzer441selects either one of the first force command waveform or the second force command waveform based on the judged timing of start of the mold-releasing and causes a switch442to switch to the selected force command waveform.

Here, when the linear motor23applies the mold-releasing force, the force sensor15detects a force pulled downward by a reaction force transferred to the mold holding mechanism1via the resin20. Upon start of the mold-releasing, the force to be detected rapidly decreases due to the absence of the reaction force, so that the force waveform analyzer441may perform decision of start of the mold-releasing from a temporal change of the force. More specifically, the following judging methods are contemplated. First, as the first method, the force waveform analyzer441may judge the timing at which the shape of the waveform of the detection value obtained by the force sensor15is similar to the pre-detected shape before and after start of the mold-releasing as the timing of start of the mold-releasing. Next, as the second method, the force waveform analyzer441may judge the timing at which the absolute value of the detection value obtained by the force sensor15does not exceed its maximum value, i.e., the absolute value of the detection value changes from increase to decrease as the timing of start of the mold-releasing. Next, as the third method, the force waveform analyzer441may judge the timing at which the sign of the determined differentiated value (corresponding to speed) of the detection value obtained by the force sensor15changes (reverses) as the timing of start of the mold-releasing. As the fourth method, the force waveform analyzer441may judge the timing at which the double differentiated value (corresponding to acceleration) of the detection value obtained by the force sensor15exceeds a predetermined set value as the timing of start of the mold-releasing. Note that these specific timings are illustrated in the followingFIG. 4. Since a change in the reaction force can be detected from a change in the command value given to the linear motor23, the command value given to the linear motor23may also be used for the decision of the timing of start of the mold-releasing, but the command given to the linear motor23changes behind a change in the reaction force. Thus, it is desirable that the detection value obtained by the force sensor15be used for the decision of the timing of start of the mold-releasing as described above.

Note that the force waveform analyzer441may also judge the timing of start of the mold-releasing using a plurality of judging methods instead of any one of the above judging methods. Also, the force waveform analyzer441sets the judging condition of the timing of start of the mold-releasing and the shape of each force command waveform in advance based on a predicted value for a required maximum mold-releasing force (Fmax), a mold-releasing time (T3-T2), a delay time in detecting the timing of start of the mold-releasing, or delay properties of the position controller41. In particular, when the force waveform analyzer441detects the timing of start of the mold-releasing, a slight delay may occur due to a response delay of the force sensor15or a processing time of the control system. Hence, the force waveform analyzer441may modify the judging method in advance so as to make the detected timing adjust beforehand by the amount of delay time. It is desirable that the force waveform analyzer441change the maximum value of the second force command waveform as appropriate depending on the maximum mold-releasing force detected by the force sensor15. It is desirable that the absolute value of the second force command waveform be slightly greater than the reaction force received from the mold10to promote the mold-releasing. However, if the absolute value is too greater than the reaction force, variation in the posture of the fine movement stage22increases due to the difference therebetween. Hence, the force waveform analyzer441may reference the detection value obtained by the force sensor15after start of the mold-releasing at any time and change a force waveform so as to maintain the force slightly greater than the detection value. Furthermore, in order to cancel out variation in posture caused by a difference between the reaction force and the force command, the force waveform analyzer441may be configured to apply a force in the reverse direction for a shot time immediately after the reaction force becomes substantially zero.

In order to avoid malfunction, the time at which the force sensor15starts detection may be limited to the time after elapse of a predetermined time subsequent to the application of the first force command waveform. The force command waveform must cancel out the reaction force at the pattern transfer position on the substrate21. In particular, when a pattern is transferred to the peripheral portion on the substrate21, the imbalance of force may occur not only in the Z-axial direction but also in the θx- and θy-directions. Hence, the force waveform analyzer441may also be adapted to distribute and output the force command waveforms in the θx- and θy-directions depending on the pattern transfer position.

The controller4may also include database47that records a predicted value for a required maximum mold-releasing force or a mold-releasing time for each type of resin or each shape of the concave-convex pattern formed on the mold10. The mold-releasing condition varies depending on the type of resin or the shape of the concave-convex pattern, resulting in a variance in the optimum value of the mold-releasing force. Hence, the database47records the relationship between a mold-releasing force and a mold-releasing time which are predetermined for each resin which may be employed or for each concave-convex pattern. In this manner, the force waveform analyzer441can select the judging condition of the timing of start of the mold-releasing which is optimum for a resin to be employed or a concave-convex pattern or the shape of the force command waveform with reference to the relationship recorded in the database47.

Furthermore, the controller4may also be adapted to include a data recording unit46that records at least any one log data of the position detection value of the substrate stage2, the amount of operation of each axis, and the detection value obtained by the force sensor15in the mold-releasing step. In this manner, the force waveform analyzer441can change the judging condition of a more appropriate timing of start of the mold-releasing and the shape of the force command waveform with reference to log data recorded in the data recording unit46. Furthermore, the judging condition of the optimized timing of start of the mold-releasing and the shape of the force command waveform are recorded in the database47, so that the force command generating unit44can use the optimum value in subsequence.

FIG. 4is a graph illustrating changes in a force detection value and a command value in the Z-axial direction in the mold-releasing step in the present embodiment, where a time is plotted on the horizontal axis. First, when the controller4causes the linear motor23to start application of the mold-releasing force (T1), the force waveform analyzer441causes the switch442to select the first force command waveform required for the mold-releasing to generate and output a force command. As shown inFIG. 2, the generated force command is added to a command generated by the position controller41as a feedforward (FF) command, and is input to the command converting unit45to be converted into a corresponding position target value. More specifically, the force waveform analyzer441gives a position target value slightly downwardly offset with respect to the position controller41to thereby generate a relative displacement between the mold10and the substrate21. In this manner, the position controller41generates a mold-releasing force as a feedback (FB) command for overcoming the reaction force in order to maintain the position target value. In this case, it should be noted that a position target value needs to be determined by calculating in advance how much reaction force is generated with respect to the amount of displacement from the position target value. Briefly, the controller4calculates the displacement of the resin corresponding to a predetermined force command using the rigidity value, i.e., the spring constant of the resin to determine a position target value based on the displacement. Here, if conversion of the first force command waveform into the position target value is appropriate, almost all commands become feedforward commands and only a few feedback commands are generated. Next, when the force waveform analyzer441detects the timing of start of the mold-releasing (T2) judged by the judging method as described above, the force waveform analyzer441causes the switch442to select the second force command waveform to generate and output a force command. The second force command waveform is a waveform for decreasing the mold-releasing force and is added as a feedforward command to a command generated by the position controller41. Note that the controller4may change the position target value of the substrate stage2in parallel fashion. For example, the controller4may cause the substrate stage2to start movement toward the next transfer position by further reducing the Z axis target value to ensure an interval between the mold10and the substrate21and changing XY-target values. In this manner, the imprint apparatus100can perform the mold-releasing step more quickly, resulting in an improvement in throughput. When a force command waveform cannot be appropriately set due to some malfunction, the force command waveform and the reaction force cannot be cancelled out. Consequently, it is also contemplated that the substrate stage2is largely displaced, and thus, for example, the fine movement stage22rises to collide with the mold10. Thus, in order to avoid such an operation, the controller4may also be adapted to stop to output a force command when the speed of movement of the fine movement stage22increases in the course of the mold-releasing.

As described above, the imprint apparatus100can suppress application of the mold-releasing force more than necessity in the mold-releasing step, and thus, can suppress a breakage of the concave-convex pattern of the mold10. In addition, in order to suppress application of the mold-releasing force more than necessity, the imprint apparatus100does not temporarily stop the mold-releasing after the mold-releasing starts, resulting in an improvement in throughput. Furthermore, variation in posture of the substrate stage2is suppressed even if the mold-releasing force is more rapidly applied thereto, resulting in a reduction in the application time of the mold-releasing force, which also can lead to an improvement in throughput. The configuration of the substrate stage which may be applied in the present embodiment is not limited to include the fine movement stage22which is supported in a non-contact by the coarse movement stage24and is controlled along six axes by the actuator as long as the force command generating unit44or the like is present. It should be noted that the imprint apparatus100which employs the substrate stage2having such a fine and coarse movement configuration exhibits an excellent floor vibration insulation performance, resulting in achieving highly-accurate positioning. In particular, in a non-contact stage such as the fine movement stage22, it is contemplated that a breakage due to an impact may occur on the non-contact stage if an excessive mold-releasing force acts, whereas to the present embodiment is also advantageous to be capable of suppressing such a breakage due to an impact.

As described above, according to the present embodiment, an imprint apparatus and an imprint method which are advantageous for improving throughput and suppressing a breakage of the concave-convex pattern formed on the mold may be provided.

Second Embodiment

Next, a description will be given of an imprint apparatus according to a second embodiment of the present invention. In the above first embodiment, the force sensor15serving as a force detector is used as a detector for detecting a physical quantity (the state of the driving device) for judging the timing of start of the mold-releasing. In contrast, a feature of the imprint apparatus according to the present embodiment lies in the fact that the laser interferometer25serving as a position detector is employed as the physical quantity detector instead of the force detector in the imprint apparatus100according to the first embodiment. In this case, the detection value is a value of the position of the fine movement stage22(the position of the substrate stage2) as the physical quantity.

If no reaction force is produced, the force generated by the linear motor23cannot be balanced, resulting in variation in the posture of the fine movement stage22. Thus, the force waveform analyzer441may analyze a variation in posture using the position detection value of the fine movement stage22detected by the laser interferometer25to judge the timing of start of the mold-releasing. More specifically, the following judging methods are contemplated. First, as the first method, the force waveform analyzer441may judge the timing at which the Z axis deviation of the fine movement stage22exceeds a predetermined value as the timing of start of the mold-releasing. Next, as the second method, the force waveform analyzer441may judge the timing which exceeds a predetermined value based on a temporal change in the Z axis speed of the fine movement stage22as the timing of start of the mold-releasing. Next, as the third method, the force waveform analyzer441may judge the timing which exceeds a predetermined value based on a temporal change in the Z axis acceleration of the fine movement stage22as the timing of start of the mold-releasing. Also, in the present embodiment, the force waveform analyzer441may judge the timing of start of the mold-releasing using a plurality of judging methods instead of any one of the above judging methods.

According to the present embodiment, the same effect as that in the first embodiment is provided and the laser interferometer has a higher responsibility than that of the force sensor, so that the timing of start of the mold-releasing can be judged quickly.

Third Embodiment

Next, a description will be given of an imprint apparatus according to a third embodiment of the present invention. In the above embodiments, the force command generating unit44is provided in the control system for the substrate stage2(the fine movement stage22). In contrast, a feature of an imprint apparatus200according to the present embodiment lies in the fact that the same force command generating unit44is provided in the control system for the mold driving mechanism14included in the mold holding mechanism1.

FIG. 5is a schematic view illustrating a configuration of the imprint apparatus200according to the present embodiment. In the imprint apparatus200, components corresponding to or similar to those in the imprint apparatus100according to the first embodiment are designated by the same reference numerals, and explanation thereof will be omitted. In the present embodiment, the mold driving mechanism14moves the mold10in the Z-axial direction so as to selectively bring the mold10into contact with the resin20on the substrate21or release the mold10from the resin20. In contrast to the substrate stage2in the first embodiment, the substrate stage3included in the imprint apparatus200does not have the fine movement stage22but has an XY stage241which is similar to the coarse movement stage24. In other words, the XY stage241is mounted on the surface plate33, places the substrate21, and moves in the XY-directions for positioning.

FIG. 6is a block diagram illustrating an exemplary control system relating to the mold driving mechanism14included in the controller4in the present embodiment. Here, the substrate stage3does not have an actuator in the Z-axial direction, and thus, cannot send a force command in the Z-axial direction to the control system relating to the substrate stage3. The mold-releasing force is generated by the mold driving mechanism14. In this case, when the mold driving mechanism14starts application of the mold-releasing force, the force command generating unit44outputs a force command so as to gradually increase an upward force. Then, as in the above embodiments, the physical quantity for judging the timing of start of the mold-releasing is detected with use of the force sensor15or the like. After decision of the timing of start of the mold-releasing, the force command generating unit44calculates an upward force with reference to the database47and transmits it to the mold driving mechanism14. The present embodiment also provides the same effect as that in the above embodiments.

A method of manufacturing article such as the aforementioned device (e.g., a microchip, a liquid crystal display) according to an embodiment of the present invention may include a step of forming a pattern on an object (e.g., wafer, glass plate, film substrate) using the aforementioned imprint apparatus. Furthermore, the article manufacturing method may include etching. When other articles such as a patterned medium (storage medium), an optical element, or the like are manufactured, the manufacturing method may include another step of processing the substrate on which a pattern has been formed instead of the etching step. The article manufacturing method of this embodiment has an advantage, as compared with a conventional article manufacturing method, in at least one of performance, quality, productivity and production cost of a device.

This application claims the benefit of Japanese Patent Application No. 2015-041491 filed on Mar. 3, 2015, which is hereby incorporated by reference herein in its entirety.