JP2015139936A - Structure production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce time required for reducing a solvent amount included in a coating film, in room temperature imprint.SOLUTION: A structure production method is characterized to have: a step for coating a coating agent including an inorganic material and solvent to a base material for forming a coating film; a step for reducing the solvent amount included in the coating film by a predetermined amount; and a step for bringing the coating film and a mold at least whose one side facing the coating film has a solvent adsorption property into contact each other, thereby transferring the mold surface shape to the coating film surface.

Description

  The present invention relates to a method for manufacturing a structure.

A room temperature nanoimprint lithography technique that is attracting attention as a fine pattern formation technique is disclosed in Patent Document 1. After applying a coating agent containing a material such as SOG (Spin-On-Glass) and a solvent to the substrate surface to form a coating film, the solvent is volatilized and imprinted on the coating film with a mold before curing is completed. Thereafter, a nano-accurate SiO ₂ fine pattern can be formed by separating the mold from the coating film.

  In addition, the SOG material is imprinted using a mold made of polydimethylsiloxane having solvent absorbability (hereinafter referred to as “PDMS”), and the solvent contained in the coating film is absorbed on the mold side to form a pattern. The forming technique is also disclosed in Non-Patent Document 1.

Japanese Patent Laid-Open No. 2003-100609

“Room-Temperature Nanoimpringing Using Liquid-Phase Hydrogen Silsesquioxane with Hard Poly (dimethylsiloxane) Mold, Jpn. J. Appl. Phys. 49 (2010) 06GL 13 (5 pages).

  However, there is a problem that it takes time to absorb the solvent on the mold side.

  An object of the present invention is to shorten the time for reducing the solvent contained in a coating film in room temperature imprinting.

  One embodiment of the present invention includes a step of forming a coating film by applying a coating agent containing an inorganic material and a solvent to a substrate, and a step of reducing a predetermined amount of the solvent contained in the coating film. A step of transferring the shape of the surface of the mold to the surface of the coating film by bringing the coating film into contact with a mold having a solvent absorption property at least on the side facing the coating film. This is a manufacturing method of the structure.

  As another aspect of one embodiment of the present invention, the mold may have flexibility.

  As another aspect of an embodiment of the present invention, the predetermined amount may be an amount by which a part of the coating film can be filled in the unevenness of the mold by its own weight.

  As another aspect of an embodiment of the present invention, the inorganic material may be a siloxane polymer.

  As another aspect of an embodiment of the present invention, the mold is preferably a resin having a porous structure.

  ADVANTAGE OF THE INVENTION According to this invention, the time which reduces the solvent contained in a coating film can be shortened in room temperature imprint.

It is a figure which shows the manufacturing process of the structure by one embodiment of this invention. It is a figure which shows typically the mode of the time change of the solvent amount after HSQ application completion.

  Hereinafter, a structure manufacturing method according to an embodiment of the present invention will be described in detail with reference to the drawings. In the following, a process of applying a coating agent containing an inorganic material and a solvent as a coating film to a substrate and forming the coating film using a solvent-absorbing mold will be described as an example.

  FIG. 1 is a process diagram showing a main process of the structure manufacturing method according to the present embodiment. As shown to Fig.1 (a), the coating film 3 is formed by apply | coating the coating agent containing an inorganic material and a solvent on the base material 1 (coating film formation process). The coating film 3 can be formed by a known coating method, and typically a spin coating method can be used. When the coating film 3 is formed by spin coating, a uniform thin film can be formed by increasing the solvent amount of the coating agent and decreasing the viscosity of the coating agent. Although there is no restriction | limiting in particular in the thickness of the coating film 3, For example, it can form in 0.01 micrometer-0.5 micrometer.

  The substrate 1 is not particularly limited. For example, glass materials such as silicon, metal, quartz glass, soda glass, fluorite, calcium fluoride, magnesium fluoride, acrylic glass, borosilicate glass, polycarbonate, polypropylene, polyethylene In addition to resin materials such as polyolefins, ceramic materials such as low expansion ceramics can be used. In addition, the substrate 1 may be provided with solvent absorbability. In this case, for example, a porous structure such as porous silicon, porous silica, ceramics, PDMS, or a solvent such as paper or fiber can be impregnated. A material having a three-dimensional network structure can be used.

  The inorganic material contained in the coating agent may be any material that can provide a hard inorganic film when the coexisting solvent decreases. For example, semiconductors such as silicon, titanium, nickel, cobalt, gold, silver, copper, palladium Materials such as platinum, tin, rhodium, indium, ruthenium, zinc, aluminum, molybdenum, chromium and the like, and inorganic polymers having oxides and nitrides thereof, or colloids thereof. be able to. In the illustrated example, an example using a siloxane polymer, which is a silicon-containing inorganic polymer, is disclosed, and in particular, an example using a hydrogenated silsesquioxane polymer (HSQ) among siloxane polymers is shown.

  The solvent contained in the coating agent can be appropriately selected according to the inorganic material. For example, methanol, ethanol, xylene, toluene, butyl acetate, cyclohexane, ethylbenzene, isopropyl alcohol, 1-propanol, 2-propanol , Methoxypropyl acetate, propylene glycol monoethyl ether acetylate and the like.

  Next, after waiting for a predetermined time, the solvent contained in the coating film 3 is decreased by a predetermined amount to form a coating film 3a in which the amount of the solvent is decreased to a predetermined amount as shown in FIG. 1B (solvent reduction step). . At this time, it is preferable to wait for a decrease in the solvent contained in the coating film 3 at room temperature. This is because when the temperature rises, a standby time required for cooling after the temperature rise may be required, or temperature unevenness may occur in the base material 1 and the amount of solvent decrease may become uneven.

  Next, as shown in FIG. 1C, the surface of the mold 5 on which the uneven pattern is formed is brought into contact with the coating film 3a. Thereby, the pattern on the surface side of the substrate 1 of the mold 5 is transferred to the surface of the coating film 3a on the substrate 1 (transfer process). The mold 5 has solvent absorbability at least on the side facing the coating film 3a. In addition, the whole mold 5 may have a solvent absorptivity. As the mold 5 having solvent absorbability, for example, a material having a porous structure can be used, and a resin having a porous structure is preferable. Specifically, PDMS may be used. Although there is no restriction | limiting in particular in the thickness of the mold 5, It is good to set in the range of 100 micrometers-3000 micrometers so that it may have flexibility. This is because, when having flexibility, the stress at the time of peeling can be reduced, and the followability to the shape on the substrate side can be improved. Note that not only the mold 5 but also both the base material 1 and the mold 5 may be made of a solvent-absorbing material, and the decrease rate of the solvent contained in the coating film 3 may be increased. The solvent contained in the coating film 3 is also absorbed by the substrate 1, whereby the coating film 3 is cured.

  As shown in FIG. 1D, by separating the mold 5 from the cured coating film 3a on the substrate 1, the pattern of the mold 5 is transferred to the coating film 3a side, and, for example, an opening O1 is formed. The coating film pattern 3b can be formed. Usually, since the substrate 1 and the mold 5 are arranged at a predetermined interval during imprinting, a part of the coating film in the opening O1 remains as a remaining film 3b '.

Further, when it is desired to remove the residual film 3b ', as shown in FIG. 1E, etching back is performed by reactive ion etching or the like for removing the residual film to completely remove the residual film. it can. If necessary, as shown in FIG. 1F, for example, a reactive ion etching method using CF ₄ , CHF ₃ or the like, for example, a Si substrate as a base material 1 and a coating film pattern 3b are formed. By processing as a mask, the substrate 1 can be finely processed.

FIG. 2 is a diagram schematically showing a change over time in the amount of the solvent contained in the coating film. Reference numeral L1 indicates a conventional example that does not undergo the solvent reduction process that is the step of FIG. 1B in the present embodiment, while reference numeral L2 indicates the present embodiment. As indicated by reference numeral L1, is started pressing of the mold at the time t _0, applied by solvent contained in the coating film decreases gradually being absorbed into the mold side, solvents a certain amount at time t ₃ is reduced The film is cured. That is, the time required for the coating film to cure is t ₃ -t ₀ .

On the other hand, in the present embodiment, as shown at L2, it waits until time t ₁ without pressing the mold at time t _0. At this time, since the surface of the coating film on the side not in contact with the base material is exposed and exposed, the solvent evaporates from the surface. The decreasing rate of the solvent that volatilizes in the opened state is faster than the decreasing rate of the solvent absorbed on the mold side in a state where the mold is in contact with the coating film. Then, for example, at time t _1, it is contacted with the mold to the coating film. Solvent contained in the coating film decreases gradually being absorbed into the mold side, to cure the coating film by reducing the solvent a certain amount at time t _2. The time required for the amount of solvent to reach the predetermined amount is t ₂ −t ₀ . Thus, according to the present embodiment, it is possible to shorten the time required for reducing the solvent in the coating film.

  Here, the timing at which the mold in this embodiment is brought into contact with the coating film can be determined according to the following policy. When the solvent of the coating film decreases and the hardness of the coating film increases, it is necessary to apply a load from at least one side of the mold and the substrate in order to perform imprinting. However, for example, when the mold has flexibility, the load causes distortion of the pattern itself and the mold housing itself. For this reason, if the solvent contained in the coating film is reduced too much, the hardness of the coating film increases, and the fidelity of pattern transfer is lost during imprinting.

  Therefore, it is preferable that the solvent in the coating film is reduced to such an extent that imprinting can be performed without applying a load that causes deformation of the mold. As such an aspect, for example, a state in which the solvent in the coating film is reduced to such an extent that imprinting can be performed by the weight of the mold can be given. In this way, the solvent contained in the coating film is formed immediately after the coating agent is applied to the base material, so as not to require a load that is accompanied by deformation of the mold, specifically, the coating film is formed mainly by the weight of the mold. What is necessary is just to perform imprint until the hardness which can be obtained is obtained.

  As described above, according to the present embodiment, it is possible to shorten the time for reducing the solvent contained in the coating film in the room temperature imprint.

Example 1
A coating agent having the following composition was prepared.

[Coating composition]
Inorganic material: Silsesquioxane hydride (Toray Dow Corning FOX-16: about 20 wt%)
・ Solvent: Methyl isobutyl ketone (about 80 wt%)
The total of inorganic material and solvent was 100 wt%.

  A quartz glass substrate (outer diameter 20 cmΦ, thickness 0.725 cm) is prepared as a base material, and a coating agent is applied onto the quartz glass substrate by a spin coat method (2500 rpm, 60 seconds) to form a coating film having a thickness of 0.05 μm. Got.

  The coating film was allowed to stand on a quartz glass substrate at room temperature, and after about 120 seconds, a PDMS mold (outer diameter 20 cmΦ, thickness 1000 μm) was gently placed on the coating film without applying a load. After waiting for 5 minutes in a state where the mold and the coating film were in contact with each other, the mold was separated from the coating film to obtain a patterned silicon oxide layer on the quartz glass substrate.

  In the above-described embodiment, the configuration and the like illustrated in the accompanying drawings are not limited to these, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  Each component of the present invention can be arbitrarily selected, and an invention having a selected configuration is also included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Base material, 3 ... Coating film, 5 ... Mold.

Claims (5)

Forming a coating film by applying a coating agent containing an inorganic material and a solvent to the substrate;
Reducing the solvent contained in the coating film by a predetermined amount;
A step of transferring the shape of the surface of the mold to the surface of the coating film by bringing the coating film into contact with a mold having a solvent absorbability at least on the side facing the coating film. Manufacturing method of structure.   The method of manufacturing a structure according to claim 1, wherein the mold has flexibility.   3. The structure according to claim 2, wherein the coating film in which the predetermined amount of the solvent is reduced is in a state in which a part of the coating film can be filled in the unevenness of the mold by the weight of the mold. Manufacturing method.   The method for manufacturing a structure according to any one of claims 1 to 3, wherein the inorganic material is a siloxane polymer.   The method for producing a structure according to any one of claims 1 to 4, wherein the mold is a resin having a porous structure.

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