JP2016054231A - Imprint device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imprint device capable of filling in high concentration a space between a template and a substrate with a replacement gas before imprinting even when continuously imprinting a resin coated on the substrate for a plurality of shots.SOLUTION: The imprint device includes: first gas supply means 15 for supplying a first space 20 between a template and a substrate 2 with a replacement gas; and first gas recovery means 17 for recovering a gas leaked from the first space, and controls to stop the gas recovery with the first gas recovery means at least during a period from immediately before releasing a pattern part from a resin to completing to release a mold.SELECTED DRAWING: Figure 2

Description

  The present invention generally relates to a processing apparatus, and more particularly to a processing apparatus for transferring a fine pattern of a template as an original to a substrate or the like. The present invention is particularly suitable for a processing apparatus using imprint technology.

  Imprinting is a technique that replaces a method for forming a fine pattern on a semiconductor device using photolithography using ultraviolet rays, X-rays, or an electron beam. Imprinting means that a template (template) on which a fine pattern is formed by electron beam exposure or the like is pressed (imprinted) onto a substrate such as a substrate coated with a resin material (resist), thereby forming a pattern on the resist. Transcript. It has already been shown that transfer of a fine shape of about 10 nm is possible, and in particular, it has been attracting attention as a means for creating a fine periodic structure of a magnetic recording medium, and research and development has been actively conducted in various places. .

  As an imprint method, there is known a method (photocuring method) in which an ultraviolet curable resin is used as a resist and the template is peeled after being exposed to light and cured in a state of being stamped with a transparent template. The semiconductor integrated circuit pattern has a minimum line width of 100 nm or less, and it is necessary to use a low-viscosity resin material in order to ensure that the resin enters the fine structure of the template.

  In addition, the imprint apparatus normally transfers the pattern sequentially onto the wafer surface by a step-and-repeat method. Here, the “step-and-repeat method” is a method in which the wafer is stepped for each batch transfer of a wafer shot and moved to the transfer area of the next shot. At this time, since the viscosity of the resin is low, it is difficult to apply the resin in advance on the entire surface of the substrate as in the exposure apparatus, and to transport and mount it. For this reason, a method has been proposed in which an appropriate amount of resin is dropped and applied to each shot or a plurality of shots.

  It is also known that when a template is imprinted on a substrate coated with a resin, if a bubble remains between the template and the resin on the substrate surface, the formed pattern is distorted. As a countermeasure, a gas such as helium or carbon dioxide (hereinafter referred to as “replacement gas”) that is highly soluble in the resin is poured between the template and the substrate to replace the air in the gap between the substrate and the template. Is disclosed in Patent Document 1.

Special table 2007-509769 gazette

  Here, it is more advantageous from the viewpoint of throughput to apply a plurality of shots of resin to the substrate at a time and continuously imprint it. However, when performing imprinting continuously, air is entrained in the space between the template and the substrate at the time of release, and the replacement gas concentration in the space between the template and the substrate cannot be sufficiently increased by the next imprinting. Occurs.

  Therefore, the present invention reduces the consumption of the replacement gas when continuously imprinting a plurality of shots of resin applied to the substrate, and the replacement gas is introduced into the space between the template and the substrate in a short time. An object of the present invention is to provide an imprint apparatus that can satisfy a high density.

  In order to achieve the above object, an imprint apparatus according to the present invention is the imprint apparatus in which a pattern portion formed on a template is continuously imprinted and released from a plurality of shots of resin applied on a substrate. A first gas supply means for supplying a replacement gas to a first space between the template and the substrate; a first gas recovery means for recovering a gas leaked from the first space; , And control is made to stop the recovery of the gas by the first gas recovery means at least from the time immediately before the mold release that separates the pattern portion from the resin to the end of the mold release.

  According to the present invention, even when a plurality of shots of resin applied to a substrate are continuously imprinted, the space between the template and the substrate can be filled with a replacement gas at a high concentration before the shot imprinting step. .

Schematic of the imprint apparatus in the first embodiment of the present invention The figure explaining operation | movement of the imprint apparatus in 1st Example of this invention. Schematic of the imprint head unit in the second embodiment of the present invention The figure explaining the stamping process of 1 shot in a prior art example The figure explaining the stamping process of the multiple shot in a prior art example

  A first embodiment of the present invention will be described below with reference to the accompanying drawings. In addition, in each figure, about the same member, the same reference number is attached | subjected and the overlapping description is abbreviate | omitted.

  FIG. 1A is a schematic cross-sectional view of the imprint apparatus 24 of the present invention. FIG. 1B is a bottom view of the imprint head unit 25. The substrate 2 on which the resins 91 and 92 are applied is mounted on the wafer stage 1. A mirror 12 is mounted on the wafer stage 1. After the reflected light 13 reflected by the mirror 12 and reference light (not shown) are caused to interfere with each other by the laser interferometer 11, the interference light is accurately detected to detect the interference of the substrate 2. The position can be measured.

  The wafer stage 1 is configured to control the position using the value of the laser interferometer 11. The method for measuring the position of the wafer stage 1 is not limited to the laser interferometer 11 shown in this embodiment, and other methods such as a linear scale may be used. The wafer stage 1 has not only positioning but also means for adjusting the posture of the substrate 2.

  The template 3 on which the transfer pattern 4 is formed is mounted on a chuck 5 integrally formed with an imprint head 7 for holding the template 3 by suction means 6 such as vacuum suction, and constitutes an imprint head unit 25. ing. The imprint head 7 includes a driving means (not shown) for moving up and down, a posture dosing mechanism (not shown), a posture control and a rotation method alignment means so that the transfer pattern 4 and the substrate 2 are in close contact with each other. (Not shown).

  The chuck 5 is provided with a hole 10 so that exposure light can be irradiated from the light source (not shown) and the illumination system 10 to the resins 91 and 92 on the substrate 2 through the template 3.

  The light source includes a halogen lamp that generates UV light, and the illumination system 10 includes a lens, an aperture, and a shutter for switching between irradiation and light shielding.

  The resins 91 and 92 are applied onto the substrate 2 by a coating device 19 provided separately.

  A nozzle 8 for supplying a replacement gas is provided in the vicinity of the template 3, and the gas supply port 16 is supplied to the first space 20 surrounded by the nozzle 8, the template 3, and the substrate 2 by the first gas supply means 15. The replacement gas is supplied from. The first gas supply means 15 is supplied with a replacement gas from a gas supply source 41. The nozzle 8 is provided near the template 3 in order to efficiently supply the replacement gas to the first space with a small amount of the replacement gas. The gas supply port 16 may be provided over the entire circumference of the nozzle 8 or may be provided separately on the + X side and the −X side of the template 3 as shown in FIG. In this case, for example, the replacement gas may be supplied from the −X side gas supply port 16 when the substrate 2 is moved in the + X direction, and from the + X side gas supply port 16 when the stage 1 is moved in the −X direction.

  A first wall member 61 extending in the direction of the substrate 2 is provided on the outer peripheral portion of the chuck 5 to form a second space 21 surrounded by the first wall member 61, the chuck 5, the nozzle 8, and the substrate 2. . Reference numeral 17 denotes first gas recovery means for recovering the gas leaked from the first space 20 to the second space 21 from the gas recovery port 18. The gas recovered by the first gas recovery means 17 is sent to the gas recovery unit 42.

  In this embodiment, the first wall member 61 is provided in order to reduce the gas leaking from the second space 21 to the external space 22, but this is not always necessary, and the stage leaks with a small amount of gas leaking to the external space 22. If there is no inconvenience in position control 1 etc., it can be omitted.

  Each operation of the imprint apparatus 24 described above is controlled by a command from a central controller (not shown).

  Here, in order to clarify the feature of the present invention, an imprint operation in the prior art will be described with reference to FIGS. FIG. 4 is a schematic view showing an example of a conventional technique for replacing the air in the space between the template and the substrate with a replacement gas.

  In FIG. 4, a white arrow indicates a flow of gas having a high replacement gas concentration, a hatched arrow indicates a flow of gas having a low replacement gas concentration, and a black arrow indicates air. In the example of FIG. 4, the nozzle 51 for supplying the replacement gas is disposed in the vicinity of the side surface of the template 3, and the replacement gas 50 supplied from the nozzle 51 is moved to the space between the template 3 and the substrate 2 using the movement of the substrate 2. 20 is filled with a replacement gas. As shown in FIG. 4C, a high concentration region 52 of the replacement gas (indicated by a broken-line square) is formed in the space 20 between the template 3 and the substrate 2 before the stamping process (FIG. Region) can be formed.

  FIG. 5 shows a state in which two shots of resins 91 and 92 are applied to the substrate 2 and are continuously stamped. When continuous imprinting is performed by the method shown in the example of the prior art, a mold releasing step (FIG. 5 (D) for separating the template 3 and the substrate 2 after imprinting on the first shot of the resin 91 (FIG. 5 (d)). e)), outside air is caught in the space 20 between the template 3 and the substrate 2 (FIG. 5E). In such a state, since the distance between the first shot and the second shot is short, the movement distance of the substrate 2 cannot be taken sufficiently. Therefore, when the resin 92 of the second shot comes under the template 4, the template 4 and the substrate 2 and the low concentration region 53 of the replacement gas remains in the space 20 between the two. Therefore, it is necessary to allow time for the replacement gas concentration in the space 20 to increase before the second shot is stamped, resulting in a decrease in throughput.

  Next, the operation of the imprint apparatus 24 according to the first embodiment of the present invention will be described with reference to FIG. In the process shown in FIG. 2A, the substrate 2 coated with the resins 91 and 92 by the coating device 19 moves in the −X direction so that the resin 91 is positioned under the pattern 4 in order to perform the first shot. 71 and 72 are flow rate adjusting valves, and 73 is a switching valve.

  The switching valve 73 switches the flow path so as to supply the replacement gas from the upstream side of the movement of the substrate 2. During the movement of the substrate 2, the replacement gas is supplied to the first space 20 by the first gas supply means 15, and the gas is recovered from the second space 21 by the first gas recovery means 17. At this time, the supplied replacement gas fills the first space 20 as the substrate 2 moves.

  In the next step shown in FIG. 2B, the movement of the substrate 2 stops when the resin 91 is positioned below the pattern 4, and alignment for imprinting the pattern 4 on the resin 91 is performed. At this time, a high concentration region 52 of the replacement gas is formed in the first space 20.

  In the next step shown in FIG. 2C, the pattern 4 is imprinted on the resin 91, and the resin 91 is exposed with exposure light. After the stamping, the gas recovery from the first gas recovery means 17 is stopped by the flow rate adjusting valve 72. Further, the flow path is switched by the switching valve 73 and the replacement gas is supplied from all the replacement gas supply ports 16. Since the gas recovery from the second space 21 is stopped, the second space 21 is filled with the replacement gas, and a high concentration region 52 of the replacement gas is formed. Further, since the replacement gas is supplied from the first gas supply means 15 to the second space 21, the second space 21 becomes a positive pressure with respect to the external space 22, and air inflow from the external space 22 to the second space 21 is suppressed. Is done.

  In the next step shown in FIG. 2D, the pattern 4 is released from the exposed resin 91. At this time, the volume of the first space 20 becomes large and a negative pressure is generated with respect to the second space 21, so that the gas flows from the second space 21 into the first space 20. Since the gas recovery from the second space 21 is stopped, the amount of replacement gas to be supplied is increased from the volume of the first space 20 and the second space 21 that increase due to the separation, so that the external space 22 The flow of air entering the second space 21 can be suppressed. In addition, since the concentration of the air that has entered the second space 21 can be reduced by increasing the volume of the second space 21 without increasing the amount of replacement gas to be supplied, the first space 20 can be reduced. A decrease in the concentration of the replacement gas flowing into the gas can be suppressed.

  In the next step shown in FIG. 2E, the substrate 2 moves in the −X direction so that the resin 92 is positioned under the pattern 4 in order to perform the second shot. At this time, the flow path is switched by the switching valve 73, and the replacement gas is supplied to the first space 20 by the first gas supply means 15 upstream of the movement of the substrate 2. Further, the flow rate adjusting valve 72 is opened and the gas is recovered from the second space 21. In the previous step shown in FIG. 2D, the first space 20 is maintained in a high substitution gas concentration state before the substrate 2 starts moving.

  In the next step shown in FIG. 2F, the movement of the substrate 2 is stopped when the resin 92 is positioned below the pattern 4, and alignment for imprinting the pattern 4 on the resin 92 is performed. Although the distance L that the substrate 2 has moved from the first shot to the second shot is as short as about 30 mm, the substitution gas concentration in the first space 20 has already increased from the previous step shown in FIG. When the substrate 2 is stopped, a high concentration region 52 of the replacement gas is formed in the first space 20.

  In the next step shown in FIG. 2G, the pattern 4 is imprinted on the resin 92, and the resin 92 is exposed with exposure light. In the stamping process of the final shot (second shot in the present embodiment) when a plurality of shots are continuously stamped, the recovery of gas from the second space 21 may be continued, or replacement with the first space 20 is performed. The gas supply may be stopped.

  As described above, according to the first embodiment of the present invention, even when a plurality of shots of resin are continuously imprinted, the replacement gas is increased in the space between the template and the substrate before the imprinting process of all shots. Can be filled to concentration.

  Next, a second embodiment of the present invention will be described. In the first embodiment, since the first gas recovery means is stopped from the time immediately before the release (FIG. 2 (c)) to the completion of the release (FIG. 2 (d)), until the release is started. The replacement gas may leak into the outer space 22. Further, when the volume of the second space is large, it takes time until the replacement gas concentration in the second space becomes high. In this second embodiment, the replacement gas concentration in the second space can be quickly increased even when the volume of the second space is large while preventing the replacement gas from leaking into the external space 22. An example of a possible imprint head unit is shown.

  FIG. 3 shows a main part of the imprint head unit 25 according to the second embodiment of the present invention. 3A is a schematic sectional view of the imprint head unit 26, and FIG. 3B is a bottom view of the imprint head unit 26. The imprint head unit 26 is provided with a second wall member 30 outside the chuck 5 of the imprint head unit 25 described in the first embodiment, and the first wall member 61, the second wall member 30, the substrate 2, and the like. A third space 23 surrounded by is formed.

  The first gas supply means 15 for supplying the replacement gas to the first space 20 controls the switching of the supply position, the supply, and the recovery by switching the switching valve 73 as in the imprint head unit 25. I can do it.

  The switching valve 74 can switch the connection between the pipe 31 and the replacement gas supply source 41 or the gas recovery unit 42, supply replacement gas to the second space 21 via the air supply / exhaust port 32, The gas can be recovered from the second space 21 through the air supply / exhaust port 32.

  The flow rate adjusting valve 75 can control the recovery and stop of gas from the third space 23 via the recovery port 34.

  Next, replacement gas supply and gas recovery steps using the imprint head unit 26 will be described. The operation of the switching valve 73 is the same as that shown in the first embodiment.

  The operation of the switching valve 74 is connected to the replacement gas supply source 41 and supplies the replacement gas to the second space 21 at least from immediately before the release to the completion of the release, and in other processes, the gas recovery unit 42. And the gas is recovered from the second space 21. That is, the first gas recovery means 35 is stopped at least from immediately before release until completion of release, and functions as a gas supply means during that time. Since the replacement gas is positively supplied to the second space 21 at least immediately before the release to the completion of the release, the replacement gas concentration in the second space 21 can be quickly increased.

  The operation of the switching valve 75 is connected to the gas recovery unit 42 while supplying the replacement gas to the second space 21, and gas that leaks from the second space 21 to the third space 23 is recovered from the recovery port 34. to recover. Therefore, even if the replacement gas is supplied to the second space, the replacement gas can be prevented from leaking into the external space 22.

  As described above, in the second embodiment of the present invention, the replacement gas concentration in the second space can be quickly increased, and the leakage of the replacement gas to the external space can be reduced.

1 stage, 2 substrates, 3 templates, 4 transfer patterns, 5 chucks,
6 adsorption means, 7 imprint head, 8 nozzles, 9 resin, 91 resin,
92 resin, 14 illumination system, 15 first gas supply means,
17, 31 1st gas recovery means, 61 1st wall member, 30 2nd wall member,
20 first space, 21 second space, 22 external space, 23 third space,
41 Replacement gas supply source, 42 Gas recovery unit, 71 Flow rate adjustment valve,
72 Flow adjustment valve, 73 switching valve, 74 switching valve,
75 Flow adjustment valve

Claims (4)

In an imprint apparatus that continuously stamps and releases a pattern portion formed in a template on a resin for a plurality of shots applied on a substrate,
First gas supply means for supplying a replacement gas to a first space between the template and the substrate;
First gas recovery means for recovering gas leaking from the first space;
Have
An imprint apparatus for controlling to stop the gas recovery by the first gas recovery means at least from immediately before releasing the pattern portion from the resin until the end of releasing.   The imprint apparatus according to claim 1, wherein a first wall member for forming a second space is provided outside a region including the template and a supply port of the gas supply unit.   The imprint apparatus according to claim 2, further comprising a second gas recovery unit configured to recover gas leaked from the second space.   A second gas supply means for supplying a replacement gas to the second space, and when the gas recovery by the first gas recovery means is stopped, the replacement gas is supplied from the second gas supply means; The imprint apparatus according to claim 2, wherein an imprinting apparatus is provided.