JP5647029B2 - Imprint apparatus and article manufacturing method - Google Patents

Description

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

  As the miniaturization of semiconductor devices progresses, attention has been paid to a microfabrication technique in which a resin pattern corresponding to a fine uneven pattern formed on a mold is formed on the substrate by pressing the resin and the mold on the substrate together. . Such a technique is called an imprint technique and can form (transfer) a fine concavo-convex structure on the order of several nanometers on a substrate.

  In the imprint technique, a photocuring method is known as one of resin curing methods for curing an uncured resin. The photocuring method generally includes an application step, a filling step, a positioning step, an exposure step, and a release step. In the application step, a resin (uncured resin) is applied (supplied) onto the substrate. In the filling step, the resin on the substrate is brought into contact with the mold to fill the mold pattern with the resin. In the positioning step, the substrate and the mold are positioned. In the exposure step, the resin is cured by irradiating ultraviolet rays through the mold. In the release step, the mold is released (peeled) from the resin (cured resin).

  In the imprint apparatus using the imprint technique, if air or the like remains in the mold pattern during the filling process, an unfilled defect (not filled with resin) occurs. In order to prevent the occurrence of such unfilled defects, a technique for supplying a gas (soluble gas) having high solubility in a resin to the space between the mold and the substrate has been proposed (Patent Document 1 and Patent Document 1). 2). On the other hand, when the soluble gas leaks to the periphery of the mold, the refractive index of the measurement optical path of the laser interferometer used for positioning the substrate stage holding the substrate is changed (measurement error). For this reason, the positioning accuracy of the substrate stage is significantly reduced. For example, if helium gas having a large refractive index difference from air is used as the soluble gas, stage positioning errors may occur on the nanometer order even at a spatial concentration of several ppm. Therefore, the conventional imprint apparatus has a recovery port for recovering the soluble gas supplied to the space between the mold and the substrate and a substrate facing the recovery port in order to prevent leakage of the soluble gas. And an opposing surface (plate member) held by the stage.

US Patent Application Publication No. 2005/72757 JP 2009-81421 A

  In order to recover the soluble gas from the recovery port without leaking to the periphery of the mold, the interval between the recovery port and the facing surface needs to be maintained at a constant interval. In addition, from the viewpoint of the productivity of the imprint apparatus, a soluble gas is supplied during a period during which imprint processing (application process, filling process, positioning process, exposure process, and release process) is performed on one substrate. Is required to continue. Therefore, it is necessary to always maintain the interval between the recovery port and the facing surface at a constant interval even during the period in which the substrate stage is moving. For this purpose, a very large facing surface is required.

  However, if the substrate stage holds such a large opposing surface, the opposing surface vibrates due to acceleration or deceleration of the substrate stage, and the substrate stage positioning is caused by vibration of the opposing surface remaining when the substrate stage is stopped. The accuracy is significantly reduced.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a technique that is advantageous in terms of positioning accuracy of a stage that holds a substrate.

  In order to achieve the above object, an imprint apparatus according to one aspect of the present invention cures the resin in a state where the resin on the substrate is in contact with the mold, and peels the mold from the cured resin. An imprint apparatus for transferring a pattern onto the substrate, the first stage holding and moving the substrate, and a first stage arranged so as to surround the periphery of the substrate held on the first stage The first plate member and the first stage are configured separately, a second stage that moves while holding the first plate member, the mold, the substrate, and the first plate member A gas mechanism including a supply port for supplying a gas to a space between, a recovery port for recovering the gas supplied to the space, and the second stage following the movement of the first stage Said to move And a control unit which controls the first stage and the second stage, and having a.

  Further objects and other aspects of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  According to the present invention, for example, a technique that is advantageous in terms of positioning accuracy of a stage that holds a substrate can be provided.

It is the schematic which shows the structure of the imprint apparatus as 1 side surface of this invention. It is a figure which shows the vicinity of the space between the mold and a board | substrate in an imprint apparatus. It is the schematic which shows the structure of the imprint apparatus as 1 side surface of this invention. It is the schematic which shows the structure of the imprint apparatus as 1 side surface of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. In addition, in each figure, the same reference number is attached | subjected about the same member and the overlapping description is abbreviate | omitted.

<First Embodiment>
FIG. 1 is a schematic diagram showing a configuration of an imprint apparatus 1 as one aspect of the present invention. The imprint apparatus 1 cures the resin in a state where the resin on the substrate and the mold are in contact with each other, and removes the mold from the cured resin to transfer the mold pattern (uneven pattern) onto the substrate. It is the processing device which performs. Here, as shown in FIG. 1, the Z axis is defined in the direction parallel to the irradiation axis of the ultraviolet rays on the mold, the X axis is defined in the direction in which the substrate moves in a plane perpendicular to the Z axis, and the X axis is The Y axis is defined in the orthogonal direction.

  The imprint apparatus 1 includes an illumination system 101, a mold head 103 that holds a mold 102, a fine movement stage 105 that holds a substrate 104 such as a wafer, a coarse movement stage 106 that supports the fine movement stage 105, and a measurement unit (first 1 measuring unit) 107. Furthermore, the imprint apparatus 1 includes a resin supply unit 108, a gas mechanism 109, a first plate member 110, a plate member stage (second stage) 111, and a measurement unit (second measurement unit) 112. And a control unit 113. In the present embodiment, the fine movement stage 105 and the coarse movement stage 106 constitute a substrate stage (first stage) that holds the substrate 104 and moves in the X-axis direction and the Y-axis direction.

  The illumination system 101 irradiates the resin on the substrate 104 with ultraviolet rays through the mold 102 during imprint processing (in a state where the resin supplied to the substrate 104 and the mold 102 are in contact with each other). The illumination system 101 includes a light source and a plurality of optical elements for adjusting light (ultraviolet rays) emitted from the light source to light suitable for imprint processing.

  The mold 102 has a rectangular shape, and has a pattern portion 102a for transferring a pattern (for example, an uneven pattern such as a circuit pattern) to the substrate 104 at the center of the substrate-side surface (surface facing the substrate 104). . The surface of the pattern portion 102a is processed with a high degree of flatness in order to improve the adhesion with the resin on the substrate 104. The mold 102 is made of a material that transmits ultraviolet rays from the illumination system 101 (for example, quartz).

  The mold head 103 is a holding device that holds and fixes the mold 102 by vacuum suction or electrostatic force. The mold head 103 includes a mechanism for driving the mold 102 in the Z-axis direction. The mold 102 is impressed (pressed) on the resin (uncured resin) on the substrate 104 with an appropriate force. The mold 102 is peeled (released) from the cured resin. The mold head 103 is provided with an observation system for observing the alignment mark on the substrate 104 via the mold 102.

  The coarse movement stage 106 supports the fine movement stage 105 in a non-contact manner, and moves in a longer stroke than the fine movement stage 105 in the XY plane. However, in this embodiment, it is not essential that the coarse movement stage 106 supports the fine movement stage 105 in a non-contact manner, and the coarse movement stage 106 and the fine movement stage 105 may be in physical contact.

  The substrate stage constituted by the fine movement stage 105 and the coarse movement stage 106 receives the substrate 104 conveyed by the conveyance mechanism and holds the substrate 104. Each of fine movement stage 105 and coarse movement stage 106 has an actuator for moving in the XY plane. The substrate 104 is corrected to a flat surface by being sucked by a chuck provided on the fine movement stage 105, and moves in the XY plane integrally with the fine movement stage 105 and the coarse movement stage 106. In the present embodiment, the substrate stage is configured to move in the XY plane. However, in order to achieve nanometer-order positioning accuracy required for imprint processing, the substrate stage moves not only in the XY plane, but also in the Z-axis direction, Z-axis rotation, X-axis rotation, and Y-axis rotation. May be configured.

  In this embodiment, the measurement unit 107 is composed of a two-frequency heterodyne laser interferometer, and measures the position of the fine movement stage 105. In this embodiment, the measurement unit 107 measures the position of the substrate stage by measuring the position of the fine movement stage 105. However, a measurement unit that measures the positions of the fine movement stage 105 and the coarse movement stage 106 is provided. Then, the position of the substrate stage may be measured. The measurement unit 107 is not limited to a laser interferometer, and may be an encoder, a capacitance sensor, an optical sensor, a laser displacement meter, or the like.

  The resin supply unit 108 includes a dispenser head including a nozzle that drops liquid photo-curing resin (imprint material), and has a function of supplying the resin to the substrate 104. The dispenser head constituting the resin supply unit 108 is, for example, a line nozzle in which nozzles are arranged in a line. The resin supply unit 108 employs a piezo jet method, a micro solenoid method, or the like, and can supply a very small volume of resin of about 1 pL (picoliter) to the substrate 104. By moving the substrate stage (scanning movement or step movement) while supplying the resin from the resin supply unit 108, the resin can be applied onto the substrate 104 (shot region).

  The gas mechanism 109 has a function of replacing the space SP1 between the mold 102, the substrate 104, and the first plate member 110 with a gas (soluble gas) having high solubility in the resin supplied to the substrate 104. When the resin on the substrate 104 and the mold 102 are brought into contact with each other (in the filling process), the gas mechanism 109 prevents (reduces) that air or the like remains in the pattern portion 102 and unfilled defects occur. . The gas mechanism 109 includes a supply port 109a that supplies a soluble gas to the space SP1, and a recovery port 109b that recovers the soluble gas supplied to the space SP1. The gas mechanism 109 includes a control valve, a flow rate adjustment valve, and the like for controlling supply and recovery of the soluble gas.

  The supply port 109a is constituted by, for example, a nozzle having a plurality of holes, and the soluble gas supplied from the supply port 109a is directed to the pattern portion 102a of the mold 102 so as not to protrude from the mold 102 to the substrate side. Thus, it arrange | positions in the vicinity of the mold 102a. The recovery port 109b is disposed outside the supply port 109a with respect to the mold 102 and so as to surround the supply port 109a. The recovery port 109b is connected to a negative pressure source, and recovers a soluble gas (particularly, a soluble gas leaking in the vicinity of the space SP1) together with surrounding air by gas suction due to the negative pressure. The recovery port 109b only needs to be able to efficiently recover the soluble gas, and includes, for example, a nozzle having a plurality of holes or a nozzle having a plurality of grooves.

  The first plate member 110 is disposed so as to face the mold 102 and surround the periphery of the substrate 104 held by the fine movement stage 105. In the present embodiment, the first plate member 110 makes the surface of the substrate 104 held by the fine movement stage 105 and a region outside the substrate 104 substantially flush with each other. The first plate member 110 prevents the soluble gas supplied to the space SP1 from the gas mechanism 109 (supply port 109a) from leaking from the space SP1 (particularly, leaking in the vicinity of the measuring unit 107). Placed in.

  The plate member stage 111 is configured separately from the substrate stage including the fine movement stage 105 and the coarse movement stage 106, and holds the first plate member 110. The plate member stage 111 has an actuator for moving in the XY plane. The first plate member 110 moves in the XY plane integrally with the plate member stage 111 while being held by the plate member stage 111.

  In this embodiment, the measurement unit 112 is configured by a two-frequency heterodyne laser interferometer, and measures the position of the plate member stage 111. However, the measuring unit 112 is not limited to the laser interferometer, and it is sufficient that the position of the plate member 110 can be measured. For example, the measurement unit 112 may be an encoder, a magnetostrictive sensor, an ultrasonic distance sensor, a capacitance sensor, or the like.

  The control unit 113 includes a CPU, a memory, and the like, and controls the entire (operation) of the imprint apparatus 1. For example, the control unit 113 controls the movement of the substrate stage based on the measurement result (the position of the substrate stage) of the measurement unit 107, and the plate member stage based on the measurement result of the measurement unit 112 (position of the plate member stage 111). The movement of 111 is controlled. At this time, the control unit 113 follows the movement of the substrate stage (synchronously) so that the plate member stage 111 moves, that is, the distance between the substrate stage and the plate member stage 111 is kept constant. Thus, the substrate stage and the plate member stage 111 are controlled.

  An operation (imprint process) of the imprint apparatus 1 will be described. First, when the substrate stage receives the substrate 104 from the transport mechanism, the substrate 104 is held on the fine movement stage 105, and a soluble gas is supplied from the supply port 109a of the gas mechanism 109 to the space SP1. Further, the soluble gas leaking from the space SP1 is recovered from the recovery port 109b of the gas mechanism 109. At this time, the interval between the recovery port 109b and the substrate 104 and the first plate member 110 is maintained at a constant interval (about 0.1 mm to 2 mm), and the recovery port 109b efficiently recovers the soluble gas. be able to. Specifically, the recovery port 109b sucks the soluble gas on the inner side and sucks air on the outer side. As described above, since the first plate member 110 held by the plate member stage 111 is disposed around the substrate 104, the dissolved gas supplied to the space SP1 is prevented from leaking from the space SP1. can do. The supply and recovery of the soluble gas by the gas mechanism 109 is continued until the imprint process for one substrate 104 is completed.

  Next, the substrate stage is moved so that the target shot region on the substrate 104 (the shot region to which the pattern of the mold 102 is to be transferred) is positioned below the resin supply unit 108 (resin supply position). The resin is supplied (applied) to the target shot area. At this time, since the plate member stage 111 holding the first plate member 110 moves following the movement of the substrate stage, the interval between the recovery port 109b, the substrate 104, and the first plate member 110 is constant. Maintained at intervals. Therefore, it is possible to prevent the soluble gas supplied to the space SP1 from leaking from the space SP1.

  Next, the substrate stage is moved so that the target shot area on the substrate 104 is positioned below (imprinting position) of the mold 102, and the resin supplied to the target shot area is brought into contact with the mold 102. Further, the substrate 104 (target shot region) and the mold 102 are positioned. Also at this time, since the plate member stage 111 holding the first plate member 110 moves following the movement of the substrate stage, the interval between the recovery port 109b and the substrate 104 and the first plate member 110 is as follows. Maintained at regular intervals. Therefore, it is possible to prevent the soluble gas supplied to the space SP1 from leaking from the space SP1.

  Next, in a state where the resin on the substrate 104 is in contact with the mold 102, the resin on the substrate 104 is irradiated with ultraviolet rays from the illumination system 101 through the mold 102 to cure the resin. Next, the mold 102 is peeled from the cured resin on the substrate 104. As a result, the pattern of the mold 102 is transferred to the target shot area on the substrate 104.

  Such an operation is performed on all shot regions on the substrate 104, and the pattern of the mold 102 is transferred to all shot regions on the substrate 104. Then, the substrate 104 held on the substrate stage (that is, the substrate 104 on which the imprint process has been completed) is transferred to the transport mechanism, and the supply of the soluble gas to the space SP1 by the gas mechanism 109 is stopped. Specifically, the supply of the soluble gas from the supply port 109a of the gas mechanism 109 is stopped, and the soluble gas supplied to the space SP1 is recovered from the recovery port 109b of the gas mechanism 109.

  As described above, in order to keep the interval between the recovery port 109b, the substrate 104, and the first plate member 110 constant, the first plate member 110 is dissolved by the gas mechanism 109. It is necessary to have a size that always covers the supply area of the sex gas. In other words, the first plate member 110 has a soluble gas supply region at all positions positioned by the plate member stage 111 during a period from when the substrate stage receives the substrate 104 to when the substrate 104 is delivered. It must have a size to cover. Thereby, the 1st board member 110 will enlarge and it will become easy to vibrate by acceleration or deceleration of a stage. However, in the present embodiment, since the first plate member 110 is held by the plate member stage 111 configured separately from the substrate stage, even if the first plate member 110 is likely to vibrate. The positioning accuracy of the substrate stage is not affected. Further, as described above, since the soluble gas is prevented from leaking in the vicinity of the measurement unit 107 used for positioning the substrate stage, the refractive index in the vicinity of the measurement unit 107 does not vary, and the substrate The stage can be positioned with high accuracy. Therefore, in the imprint apparatus 1, the substrate 104 can be positioned with high accuracy at the resin supply position and the stamping position, and the substrate 104 and the mold 102 can be positioned with high accuracy.

<Second Embodiment>
The imprint apparatus 1 may further include a second plate member 114 as shown in FIG. The second plate member 114 is disposed between the substrate 104 and the first plate member 110 so as to face the mold 102 and surround the periphery of the substrate 104 held by the fine movement stage 105 (substrate stage). In the present embodiment, the second plate member 114 substantially covers the surface of the substrate 104 held by the fine movement stage 105 and the first plate member 110 and the region between the substrate 104 and the first plate member 110. Make the same plane. The second plate member 114 is held by the fine movement stage 105 (substrate stage).

  A space (space SP1) on the mold side of the substrate 104 between the first plate member 110 and the second plate member 114 without bringing the first plate member 110 and the second plate member 114 into contact with each other. It is preferable to provide a separation unit 115 that separates the space SP2 on the opposite side of the space. For example, the separating portion 115 extends from the first plate member 110 and extends from the second plate member 114 and the member 115a having a convex portion at the tip on the second plate member 114 side. It is comprised with the member 115b which has a recessed part in the front-end | tip at the side of the plate member 110 of this. The convex part of the member 115a and the concave part of the member 115b are fitted in a non-contact manner. As described above, by providing the separation unit 115, the dissolved gas supplied to the space SP <b> 1 is located between the first plate member 110 and the second plate member 114 in the space SP <b> 2, that is, in the vicinity of the measurement unit 107. Leakage can be prevented.

  In the present embodiment, since the fine movement stage 105 holds the second plate member 114, the weight of the fine movement stage 105 increases. Therefore, the size of the second plate member 114 is preferably made sufficiently smaller than the size of the first plate member 110 so that the increase in the weight of the fine movement stage 105 by the second plate member 114 can be ignored.

<Third Embodiment>
The first plate member 110 can be held not on the plate member stage 111 but on the coarse movement stage 106 as shown in FIG. Fine movement stage 105 is supported in a floating state by a linear motor having a self-weight cancel function attached to coarse movement stage 106 without physically contacting coarse movement stage 106. In the present embodiment, fine movement stage 105 is controlled based on the measurement result of measurement unit (first measurement unit) 107. On the other hand, coarse movement stage 106 is configured by a laser interferometer or the like, and is controlled based on the measurement result of measurement unit (second measurement unit) 118 that measures the position of coarse movement stage 106. Therefore, the coarse movement stage 106 can be regarded as being configured separately from the fine movement stage 105.

  In the present embodiment, since the first plate member 110 is held by the coarse movement stage 106, the vibration of the first plate member 110 due to the acceleration or deceleration of the stage mainly affects the coarse movement stage 106. However, since fine movement stage 105 is supported in a non-contact manner on coarse movement stage 106, the vibration of first plate member 110 does not directly affect fine movement stage 105. Therefore, the positioning accuracy of the fine movement stage 105 is not lowered by the vibration of the first plate member 110, and the substrate 104 held by the fine movement stage 105 can be positioned with high accuracy at the resin supply position or the stamping position.

  In this embodiment, the position of the coarse movement stage 106 is directly measured by the measuring unit 118. However, a measurement unit that measures the relative position between the fine movement stage 105 and the coarse movement stage 106 may be provided, and each of the fine movement stage 105 and the coarse movement stage 106 may be controlled based on the measurement result of the measurement unit.

<Fourth Embodiment>
When the imprint apparatus 1 is maintained or when the chuck provided on the fine movement stage 105 is replaced, the first plate member 110 disposed near the mold 102 or the substrate 104 may become an obstacle. In such a case, as shown in FIG. 4, an attachment / detachment mechanism 120 for attaching / detaching the first plate member 110 to / from the stage (coarse movement stage 106 or plate member stage 111) may be provided. The attachment / detachment mechanism 120 includes, for example, an attachment / detachment arm, and has a function of holding the first plate member 110 on the stage and removing the first plate member 110 from the stage. Specifically, the stage holding the first plate member 110 is moved so that the first plate member 110 is positioned under the attachment / detachment arm constituting the attachment / detachment mechanism 120. Then, the first plate member 110 is lifted in the Z-axis direction by the detachable arm, and the first plate member 110 is removed from the stage and away from the vicinity of the mold 102 and the substrate 104. As a result, a space for maintenance of the imprint apparatus 1 and replacement of the chuck can be secured, and these operations can be easily performed.

<Fifth Embodiment>
As described above, the imprint apparatus 1 can position the substrate 104 at the resin supply position or the stamping position with high accuracy, and can position the substrate 104 and the mold 102 with high accuracy. Therefore, the imprint apparatus 1 can manufacture high-quality devices (semiconductor devices, liquid crystal display elements, etc.) with high productivity. The method for manufacturing a device as an article includes a step of transferring (forming) a pattern onto a substrate (wafer, glass plate, film-like substrate, etc.) using the imprint apparatus 1. The manufacturing method further includes a step of etching the substrate on which the pattern is transferred. In addition, when manufacturing other articles, such as a pattern dot media (recording medium) and an optical element, this manufacturing method includes the other process step which processes the board | substrate with which the pattern was transferred instead of an etching step. .

  As mentioned above, although preferable embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

Claims (8)

An imprint apparatus that cures the resin in a state where the resin on the substrate is in contact with the mold, and transfers the pattern onto the substrate by peeling the mold from the cured resin,
A first stage that holds and moves the substrate;
A first plate member disposed so as to surround the periphery of the substrate held by the first stage;
A second stage configured separately from the first stage and moving while holding the first plate member;
A gas mechanism including a supply port for supplying gas to a space between the mold and the substrate and the first plate member; and a recovery port for recovering the gas supplied to the space;
A controller for controlling the first stage and the second stage so that the second stage moves following the movement of the first stage;
An imprint apparatus comprising:   The first plate member is positioned during a period from when the first stage receives the substrate from a transport mechanism that transports the substrate to when the substrate is transferred to the transport mechanism. The imprint apparatus according to claim 1, wherein the imprint apparatus has a size that covers a supply region of the gas from the supply port to the space at all positions. A first measurement unit for measuring the position of the first stage;
A second measuring unit for measuring the position of the second stage;
Further comprising
The control unit controls movement of the first stage based on a measurement result of the first measurement unit, and controls movement of the second stage based on a measurement result of the second measurement unit. The imprint apparatus according to claim 1. The first stage is a fine movement stage;
The imprint apparatus according to claim 1, wherein the second stage is a coarse movement stage that supports the fine movement stage in a non-contact manner. A second plate member disposed between the substrate and the first plate member so as to surround the periphery of the substrate held by the first stage;
The imprint apparatus according to claim 1, wherein the second plate member is held by the first stage.   A separation unit that separates the space on the mold side of the substrate from the space on the opposite side of the space on the mold side of the substrate without contacting the first plate member and the second plate member. The imprint apparatus according to claim 5, further comprising:   The apparatus further comprises an attaching / detaching mechanism for holding the first plate member on the second stage and removing the first plate member held on the second stage from the second stage. The imprint apparatus according to claim 1. Forming a resin pattern on a substrate using the imprint apparatus according to claim 1;
Processing the substrate on which the pattern is formed;
A method for producing an article comprising:

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