JP2015149390A - Imprint device, die, and method of manufacturing article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imprint device which is advantageous for inhibiting particles from being attached to a pattern part of a die.SOLUTION: An imprint device 100 is formed by a dielectric body and transfers a pattern to an imprint material supplied to a substrate using a die 5 having a pattern part 5a in which the pattern is formed and a first conductive film 30. This device includes: a second conductive film 31 that is installed at a position opposite to the first conductive film 30 via a body of the die 5; and a power supply 32 that is connected to the first conductive film 30 and the second conductive film 31 and electrifies electrical charges by energizing the first conductive film 30 and the second conductive film 31.

Description

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

  In addition to the conventional photolithography technology, there is a microfabrication technology in which a resin (imprint material, photocurable resin) on a substrate is molded with a mold (also referred to as a mold or a template) to form a resin pattern on the substrate. This technique is also called an imprint technique, and can form a fine structure on the order of several nanometers on a substrate. For example, one of the imprint techniques is a photocuring method. In an imprint apparatus employing a photocuring method, first, a resin is applied (supplied) to one of the pattern formation regions on the substrate. Next, a resin on the substrate is molded using a mold having a pattern portion. Then, the resin pattern is formed on the substrate by irradiating light to cure the resin and then separating it. In addition to the photocuring method, for example, there is a thermal cycle method, but these differences are in the method of curing the resin, and the process until the resin pattern is molded using a mold is basically the same. It is.

  In such an imprint apparatus, miniaturization is required as described above, and the adhesion of particles (dust, foreign matter) to the pattern portion of the mold may affect the pattern to be molded, and is desirable. Absent. Here, the cause of foreign matter adhering to the pattern portion is generated when the mold and the resin on the substrate are peeled off, and static electricity that attracts surrounding particles to the mold is raised. Therefore, in order to remove static electricity generated in the mold when it is peeled off, Patent Document 1 discloses a transfer apparatus including an ionizer that performs static elimination of the mold. Patent Document 2 discloses a transfer device in which a conductive film is arranged in a pattern portion and the static electricity is guided to the ground via a holder. On the other hand, Patent Document 3 discloses a substrate transport device that suppresses the adhesion of particles to the substrate by generating static electricity in the surroundings, although different from the transfer device.

JP 2009-286085 A JP 2009-241372 A JP 2008-300778 A

  Here, the techniques disclosed in Patent Documents 1 and 2 are effective in promoting the movement and removal of particles themselves by gravity by removing static electricity from the mold. However, particles having a small particle size have a low effect of gravity sedimentation and continue to float on the spot, so that it is difficult to prevent particles from adhering to the pattern portion. On the other hand, the technique disclosed in Patent Document 3 is effective for particles having a small particle diameter. However, even if this technology is applied to an imprinting device and static electricity is generated at a location away from the mold, particles floating near the mold or the substrate cannot be moved easily. It is difficult to suppress the adhesion of particles.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an imprint apparatus that is advantageous for suppressing adhesion of particles to a pattern portion of a mold, for example.

  In order to solve the above-described problems, the present invention provides a pattern formed on a substrate using a mold that is formed of a dielectric and has a pattern portion on which a pattern is formed and a first conductive film. An imprint apparatus for transferring the first conductive film, the second conductive film disposed at a position facing the first conductive film through the main body of the mold, and connected to the first conductive film and the second conductive film. And a power source that electrifies and charges the film and the second conductive film.

  According to the present invention, for example, it is possible to provide an imprint apparatus that is advantageous for suppressing adhesion of particles to a pattern portion of a mold.

It is a figure which shows the structure of the imprint apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the mold in 1st Embodiment, and the part in connection with it. It is a graph which shows the speed with respect to the particle size of a particle. It is a figure explaining operation | movement of the imprint apparatus in 2nd Embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First embodiment)
First, the imprint apparatus according to the first embodiment of the present invention will be described. FIG. 1 is a schematic diagram illustrating a configuration of an imprint apparatus 100 according to the present embodiment. The imprint apparatus 100 is used for manufacturing a semiconductor device or the like as an article. The imprint apparatus 100 is formed by bringing an uncured resin 15 applied on a wafer 1 (on a substrate) into contact with a mold 5 to form the resin on the wafer 1. This is an apparatus for forming 15 patterns. Here, an imprint apparatus employing a photocuring method is used. Further, in the following drawings, the Z axis is taken in the vertical direction (vertical direction), and the X axis and the Y axis perpendicular to each other are taken in a plane perpendicular to the Z axis. First, the imprint apparatus 100 includes an illumination system 6, a mold holding mechanism 16, an alignment measurement system 11, a wafer stage 3, a coating unit 17, and a control unit 18.

  The illumination system 6 adjusts the ultraviolet rays 19 emitted from the light source to light suitable for imprinting and irradiates the mold 5 during imprint processing. The light source may be a lamp such as a mercury lamp, but is not particularly limited as long as it is a light source that transmits light having a wavelength that passes through the mold 5 and cures the resin 15. Here, since a light source that irradiates ultraviolet rays 19 is used, an ultraviolet curable resin is used as the resin 15. In this embodiment, since the photocuring method is employed, the illumination system 6 is installed. However, for example, when the thermosetting method is employed, the thermosetting resin is cured instead of the illumination system 6. The heat source part will be installed.

  The mold 5 includes a pattern portion 5a on a surface facing the wafer 1 in which a concavo-convex pattern to be transferred such as a circuit pattern is formed three-dimensionally. Details of the mold 5 will be described later. The mold holding mechanism 16 is supported by the surface plate 10 and includes a mold chuck (holding unit) 20 that holds the mold 5, and a mold driving mechanism (not shown) that holds the mold chuck 20 and moves the mold 5. The mold chuck 20 can hold the mold 5 by attracting the outer peripheral area of the irradiation surface of the ultraviolet ray 19 in the mold 5 by a vacuum adsorption force or electrostatic force. Further, the mold chuck 20 and the mold driving mechanism have an opening region at the center (inner side) so that the ultraviolet rays 19 irradiated from the illumination system 6 pass through the mold 5 toward the wafer 1. The mold driving mechanism moves the mold 5 in each axial direction so as to selectively perform pressing or separation between the mold 5 and the resin 15 on the wafer 1. As a power source that can be employed in the mold drive mechanism, for example, there is a linear motor or an air cylinder. Moreover, in order to correspond to the highly accurate positioning of the mold 5, you may be comprised from several drive systems, such as a coarse motion drive system and a fine motion drive system. In addition to the Z-axis direction, there is also a configuration having a position adjustment function in the X-axis direction, the Y-axis direction, or the θ (rotation around the Z-axis) direction, a tilt function for correcting the tilt of the mold 5, and the like. obtain. Note that the pressing and separating operation during the imprint process may be realized by moving the mold 5 in the Z-axis direction, but may be realized by moving the wafer stage 3 in the Z-axis direction, or Both of them may be moved relatively.

  Although not shown, the alignment measurement system 11 optically observes the alignment mark formed in advance on the mold 5 and the alignment mark formed on the wafer 1 simultaneously. The controller 18 refers to the result observed by the alignment measurement system 11 when aligning the mold 5 and the wafer 1 and obtains the relative positional relationship between them. As the alignment measurement system 11, for example, an automatic adjustment scope (AAS) can be adopted.

  The wafer 1 is, for example, a single crystal silicon substrate or an SOI (Silicon on Insulator) substrate, and a resin 15 is applied to the surface to be processed. The wafer stage 3 holds the wafer 1 and performs alignment between the mold 5 and the resin 15 when pressing the mold 5 and the resin 15 on the wafer 1. The wafer stage 3 has a wafer chuck 2 that holds the wafer 1 by an attractive force, and a stage drive that holds the wafer chuck 2 by mechanical means and can move at least in the direction along the surface of the wafer 1 on the stage surface plate 4. Mechanism. Examples of power sources that can be used in the stage drive mechanism include a linear motor and a planar motor. The stage drive mechanism may also be composed of a plurality of drive systems such as a coarse drive system and a fine drive system in each direction of the X axis and the Y axis. Furthermore, there may be a configuration having a drive system for position adjustment in the Z-axis direction, a position adjustment function in the θ direction of the wafer 1, or a tilt function for correcting the tilt of the wafer 1.

  The application unit 17 is installed in the vicinity of the mold holding mechanism 16 and applies the resin 15 with a desired application amount and a desired application distribution onto a shot as a pattern formation region existing on the wafer 1. Here, since the pattern part 5a formed in the mold 5 has a density distribution, it is desirable that the application part 17 apply an amount of the resin 15 on the wafer 1 according to the density distribution. Therefore, an ink jet method is suitable as a method for applying the resin 15. In this case, the application unit 17 includes an ink jet type discharge unit 7, a tank 8 that stores the resin 15, and a supply pipe 9 that supplies the resin from the tank 8 to the discharge unit 7. The resin 15 is a photo-curable resin (imprint material) having a property of being cured by receiving ultraviolet rays 19 and is appropriately selected according to various conditions such as an article manufacturing process. The resin 15 is mixed with a release agent for facilitating separation after pressing the mold 5.

  The control unit 18 can control operation and adjustment of each component of the imprint apparatus 100. The control unit 18 is configured by, for example, a computer and is connected to each component of the imprint apparatus 100 via a line, and can control each component according to a program or the like. The control unit 18 may be configured integrally with other parts of the imprint apparatus 100 (in a common casing), or separate from other parts of the imprint apparatus 100 (in another casing). To).

  Next, the mold 5 and the configuration related thereto will be described in detail. FIG. 2 is a schematic view showing the mold 5 and parts related thereto. FIG. 2A is a side view showing the mold 5 held by the mold chuck 20 and the components connected to the mold 5. FIG. 2B is a plan view showing a surface (hereinafter referred to as “first surface”) on which the pattern portion 5 a of the mold 5 is formed. The mold 5 has a polygonal shape (preferably rectangular or square) and has a pattern portion 5a at the center of the first surface. The material of the mold 5 is preferably capable of transmitting the ultraviolet light 19 and has a low coefficient of thermal expansion, and may be quartz, for example. Moreover, the mold 5 has a first conductive film 30 that can be connected to a power source 32 described later on the first surface. Similarly, the mold 5 has the second conductive film 31 on the second surface which is the surface opposite to the first surface (the surface irradiated with light from the illumination system 6). As a material of each of the conductive films 30 and 31, for example, carbon may be used in addition to various metals. Here, the first conductive film 30 and the second conductive film 31, in particular, as shown in FIG. 2A representing the first conductive film 30, there is a pattern portion 5a, and light from the illumination system 6 is present. It is not provided in the area where light is transmitted. The imprint apparatus 100 is installed in the power supply 32, the conductive wire 33 connected from the power supply 32 to the first conductive film 30 and the second conductive film 31, and the conductive wire 33. And a switch 34 for switching.

  Next, the operation of the mold 5 having the conductive films 30 and 31 will be described. Since the material of the main body of the mold 5 is a dielectric, when the control unit 18 switches the switch 34 and energizes, an electric field is generated between the first conductive film 30 and the second conductive film 31, and the conductive films 30 and 31. Electric charge is stored in. Thereby, particles existing in the vicinity (space) of the pattern portion 5a are attracted (collected) on the first conductive film 30 by the electrostatic force.

FIG. 3 is a graph showing the velocity V (m / s) with respect to the particle diameter D _p (μm) of particles as floating particles. In FIG. 3, the solid line indicates the gravitational settling speed (speed at which fine particles settle in the fluid) V _g expressed by the formula (1) (so-called Stokes formula). On the other hand, the dotted line indicates the velocity V _e regarding the electrostatic force expressed by the formula (2) (velocity when the fine particles move at a constant velocity in a fluid to which an electric field is applied).

Where ρ _p is the particle density (kg / m ³ ), ρ is the fluid density (kg / m ³ ), μ is the fluid viscosity (Pa · s), and g is the gravitational acceleration (m / s ² ). Show.

Where q is the number of charged particles, e is the elementary charge (c), E is the electric field (V / m), and C _c is Cunningham's correction coefficient.

As shown in FIG. 3, the particle is less affected by gravity as the particle size is smaller, and conversely, the influence of electrostatic force is increased. The intersection of the curves of the velocity V _e regarding gravitational settling velocity V _g and electrostatic forces shows this state, a particle size of approximately 0.05 .mu.m. Therefore, it can be seen that small (minimal) particles having a particle size of 0.05 μm or less are easily affected by electrostatic force, so that the attracting effect according to the present embodiment is large.

  Here, since the 1st electrically conductive film 30 is installed in the surface except the installation part of the pattern part 5a in a 1st surface as mentioned above, even if it supplies with electricity, a particle adheres to the pattern part 5a. There is no. Further, the polarity (positive or negative) of the stored charge can be switched by changing the switching method of the power source 32. That is, the control unit 18 can attract negatively charged particles by controlling the first conductive film 30 to store positive charges, that is, to generate a positive electrostatic force. In addition, the control unit 18 can attract positively charged particles by controlling the first conductive film 30 to store negative charges, that is, to generate a negative electrostatic force. . For the particles attracted to the first conductive film 30, for example, by installing a device having a charge eliminating effect such as an ionizer on the wafer stage 3 and appropriately scanning the vicinity of the surface of the first conductive film 30, It is good also as what removes electricity with an ionizer. Alternatively, the attracted particles may be collected by attaching a sticky substance (for example, polyimide) to the surface of the first conductive film 30 and removed later.

  Furthermore, although not shown, the control unit 18 may be configured to connect the conductive films 30 and 31 to the ground by switching the electric circuit and remove the electric charge stored in the conductive films 30 and 31. This is effective for removing the charge of the mold chuck 20 in advance in order to suppress the peeling charging between the mold 5 and the wafer 1 during the imprint process. Further, in order to remove the charge generated in the mold 5 when the mold 5 is separated from the cured resin 15 (released), the conductive films 30 and 31 may be connected to the ground after the release. By removing the charge from the mold 5 after the mold release, it is possible to prevent particles from adhering to the pattern portion 5a.

  As a result, the imprint apparatus 100 can suitably remove particles existing in the vicinity of the pattern portion 5a, so that the particles are prevented from adhering to the pattern portion 5a and are formed on the wafer 1 as a result. Generation of pattern defects can be reduced.

  As described above, according to the present embodiment, it is possible to provide an imprint apparatus that is advantageous in suppressing the adhesion of particles to the pattern portion 5a of the mold 5.

  In the above description, the second conductive film 31 is disposed on the second surface of the mold 5, but the present invention is not limited thereto, and the surface of the mold chuck 20 (the surface facing the first surface of the mold 5 is Even if it is installed on the contact surface), the same effect is obtained. In the above description, each of the conductive films 30 and 31 is provided only on the first surface or the second surface and a surface parallel to the XY plane. However, the present invention is not limited to this. . For example, as long as the first conductive film 30 and the second conductive film 31 are not in contact with each other, the conductive films 30 and 31 may extend to the side surface of the mold 5. In addition, the first conductive film may not be formed in all regions except the pattern portion 5 a on the first surface of the mold 5. Similarly, the second conductive film 31 may be formed not only on the entire second surface but also on a part of the second surface.

(Second Embodiment)
Next, an imprint apparatus according to the second embodiment of the present invention will be described. In the first embodiment, attention is paid to particles floating in the vicinity of the pattern portion 5a of the mold 5. For example, the particles existing on the wafer 1 or the wafer stage 3 are also shown in the present embodiment. The removal can be suitably performed by driving.

  FIG. 4 is a schematic side view for explaining the operation of the imprint apparatus according to this embodiment. The control unit 18 energizes the conductive films 30 and 31 as in the first embodiment. Further, in the present embodiment, the control unit 18 drives the wafer stage 3 on which the wafer 1 is placed as it is, and moves it in the XY axis direction. As a result, even when particles are present on the wafer 1 or the wafer stage 3, the particles can be attracted by the electrostatic force of the first conductive film 30. By performing such particle removal operation before normal imprint operation (pressing operation), for example, during an alignment operation that optimizes the relative positional relationship between the wafer 1 and the pattern portion 5a of the mold 5, throughput is achieved. There is also an advantage that the influence on can be suppressed.

(Product manufacturing method)
A method for manufacturing a device (semiconductor integrated circuit element, liquid crystal display element, etc.) as an article includes a step of forming a pattern on a substrate (wafer, glass plate, film-like substrate) using the above-described imprint apparatus. Furthermore, the manufacturing method may include a step of etching the substrate on which the pattern is formed. In the case of manufacturing other articles such as patterned media (recording media) and optical elements, the manufacturing method may include other processes for processing a substrate on which a pattern is formed instead of etching. The method for manufacturing an article according to the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

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

DESCRIPTION OF SYMBOLS 5 Mold 5a Pattern part 30 1st electrically conductive film 31 2nd electrically conductive film 32 Power supply 100 Imprint apparatus

Claims (8)

An imprint apparatus for transferring the pattern to an imprint material supplied on a substrate using a mold having a pattern portion formed with a dielectric and having a pattern and a first conductive film,
A second conductive film disposed at a position facing the first conductive film via the main body of the mold;
A power source connected to the first conductive film and the second conductive film and energized to charge the first conductive film and the second conductive film;
An imprint apparatus comprising:   The imprint apparatus according to claim 1, wherein the second conductive film is disposed on the mold. A holding portion for holding the mold;
The second conductive film is disposed on a surface of the holding portion that contacts the mold;
The imprint apparatus according to claim 1.   The imprint apparatus according to any one of claims 1 to 3, further comprising a mechanism for switching a polarity of electric charges charged in the first conductive film and the second conductive film.   5. The imprint apparatus according to claim 1, further comprising an electric circuit that connects the first conductive film and the second conductive film to ground. 6.   The imprint apparatus according to any one of claims 1 to 5, wherein the first conductive film is provided with a sticky substance on a surface facing the space. A mold for use in an imprint apparatus that has a pattern portion on which a pattern is formed, and that transfers the pattern to the imprint material by bringing the pattern portion into contact with the imprint material supplied on the substrate. ,
A first conductive film is formed on a surface formed of a dielectric and having the pattern portion formed thereon,
The first conductive film is connectable to a power source together with a second conductive film disposed at a position facing the first conductive film via the main body of the mold, and is charged with electric current from the power source.
A type characterized by that. Forming an imprint material pattern on a substrate using the imprint apparatus according to any one of claims 1 to 6;
Processing the substrate on which the pattern is formed in the step;
A method for producing an article comprising:

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