WO2008072498A1

WO2008072498A1 - Mold for optical element, having nanostructure, mold for nanostructure, method for manufacturing the mold, and optical element

Info

Publication number: WO2008072498A1
Application number: PCT/JP2007/073321
Authority: WO
Inventors: Kazuma Kurihara; Takayuki Shima; Junji Tominaga
Original assignee: National Institute Of Advanced Industrial Science And Technology
Priority date: 2006-12-13
Filing date: 2007-12-03
Publication date: 2008-06-19

Abstract

This invention provides a method for manufacturing a mold for an optical element, having a nanostructure of nano-order fine concavoconvex face on a surface of a substrate (2) through a simple process. One or more etching transfer layers (3) are formed on a substrate (2). A thin film (4) for semispherical fine particle formation is formed on the etching transfer layer (3). Aggregation, decomposition, or nucleation is allowed to take place in a material constituting the thin film (4) by taking advantage of any of a thermal reaction, a photoreaction, and a gas reaction, or a complex reaction of these reactions, whereby a plurality of semispherical island-shaped fine particles are formed. The etching transfer layer (3) and the substrate (2) are successively etched by a reactant gas using the plurality of island-shaped fine particles (5) as a protective mask to form a fine conical pattern on the substrate (2) and thus to manufacture a mold (1) for an optical element, having a fine concavoconvex face (a nanostructure mold face) (1') on a surface of the substrate (2).

Description

Specification

Mold for optical element having nanostructure, mold for nanostructure, manufacturing method thereof and optical element

Technical field

TECHNICAL FIELD [0001] The present invention relates to an optical element having a nanostructure used for high-sensitivity detection in the bio or medical field, or a mold for forming a nanostructure, a method for producing the same, and an optical element. The mold for nanostructure is a superordinate concept of “mold for optical element having nanostructure”.

The “nanostructure” mentioned here is a high-spectrum nanostructure used for high-sensitivity detection in the bio and medical fields, and the “nanostructure mold” has the high aspect ratio. This is a mold used to mold nanostructures. Moreover, this nanostructure can be used, for example, for heat dissipation control, heat conduction control of materials, and wettability control.

The “optical element having a nanostructure” referred to herein is a sensing chip or the like used for highly sensitive detection in the bio or medical field, and the “molding die for an optical element having a nanostructure” It is a shaping | molding die used for shaping | molding of the sensing chip of this.

Background art

[0004] Conventionally, nanostructures can improve detection sensitivity in optical elements used for fluorescence analysis and polarization analysis in the bio and medical fields. For this reason, surface treatment is performed on the substrate surface in order to achieve high detection sensitivity. As a specific method of this surface treatment, a method of forming a fine and dense uneven shape on the substrate surface is known.

[0005] When a periodic uneven shape is provided on the substrate surface in this way, the surface area of the substrate can be dramatically increased, so that the detection sensitivity can be greatly improved (for example, patents) Reference 1 and Patent Reference 2).

[0006] In order to realize such a fine nanostructure, a fine pattern with a wavelength equal to or less than a wavelength is required. Therefore, an electron beam lithography method is used to produce such a fine structure. The method is known. In this method, after applying an electron beam resist, patterning is performed using an electron beam, and processing (etching) of the substrate is performed using reactive etching. How to do it.

[0007] It is also known that a nano-periodic structure can be produced using anodized porous alumina to produce a fine nanostructure (see, for example, Patent Document 3 and Patent Document 4). The preparation method using anodized porous alumina is a method in which aluminum is anodized in a strong alkali solution such as sulfuric acid to self-form periodic nanoholes on the aluminum surface.

Patent Document 1: Japanese Patent Application Laid-Open No. 2006-300726

Patent Document 2: JP 2005-337771 A

Patent Document 3: Japanese Patent Laid-Open No. 2006-62049

Patent Document 4: Japanese Unexamined Patent Application Publication No. 2006-68827

Disclosure of the invention

Problems to be solved by the invention

[0009] However, in the method of manufacturing a nanostructure using an electron beam drawing apparatus, it is necessary to perform patterning by scanning an electron beam, and thus it takes time to form a pattern with extremely slow drawing throughput. In addition, for this reason, there is a problem that the cost is increased in order to cope with an optical element having a large area.

[0010] In addition, the method for producing a fine nanostructure using anodized porous alumina can form a large-area periodic nanostructure at once, but the substrate material is limited. There's a problem.

[0011] Furthermore, the method using anodized porous alumina has a problem in that high-precision voltage / current control is required to produce a uniform nanostructure over a large area. In addition, the processing conditions change depending on the substrate size and processing area, and it is difficult to obtain reproducibility.

[0012] The present invention aims to solve the above-mentioned problems, and an object of the present invention is to provide a molding die for an optical element having the following nanostructure, and molding for a nanostructure. It is a point which implement | achieves a type | mold, its manufacturing method, and an optical element.

(1) The mold for an optical element or nanostructure having a nanostructure according to the present invention has a nanostructure consisting of a large-area and complex-shaped structure uniformly on the substrate surface. In an optical element having a nanostructure and used for fluorescence analysis or polarization analysis in bio or medical fields, the detection sensitivity can be further improved.

(2) The method for producing a molding die for optical elements or a nanostructure according to the present invention is a method that can be produced by only a dry process with a small number of steps and high productivity.

(3) The optical element according to the present invention has a nanostructure having a fine uneven surface on the substrate surface and a high aspect ratio nanopattern arranged in a random manner. Preferably, the nanopattern is a light source. It is an optical element provided with a nano pattern having a structure in which an interval equal to or less than the wavelength is maintained.

Means for solving the problem

[0013] In order to solve the above-mentioned problems, the present invention provides a method for manufacturing a mold for an optical element or nanostructure having a nanostructure having a fine uneven surface on a substrate surface, wherein one layer is formed on the substrate. The above-described etching transfer layer is formed, and a thin film for generating island-shaped fine particles is formed on the etching transfer layer, and either a thermal reaction, a photoreaction, a chemical reaction, or a composite reaction thereof is used for the thin film. Then, a plurality of island-shaped fine particles are formed by causing an aggregation action, a decomposition action, or a nucleation action of the thin film material, and the etching transfer layer and the substrate are sequentially etched using the plurality of island-shaped fine particles as a protective mask. Thus, a method for producing a nanostructure or an optical structure having a nanostructure, characterized by forming a convex high aspect ratio pattern on a fine surface of a substrate.

[0014] Each of the plurality of island-shaped fine particles has a nanometer order, and forms a nano-pattern that is randomly arranged while maintaining an interval equal to or smaller than the wavelength of the light source targeted. I prefer to do it.

[0015] The material of the thin film is mainly composed of a substance containing silver, gold, platinum, or palladium as a main component, or a component of silver, gold, platinum, palladium, tungsten, bismuth, or tellurium. Preferred is oxide or nitride! /.

[0016] The island-shaped fine particles have an average particle diameter of 5 nm to OOOnm, and the average interval between the plurality of island-shaped fine particles is preferably 10 nm to 2000 nm.

[0017] The substrate is made of quartz glass, resin, silicon, gallium nitride, gallium arsenide, indium phosphide.

Metals based on nickel, iron, titanium, carbon, sapphire, or carbon nitride Or it is preferable to be non-metallic.

[0018] The etching transfer layer is preferably composed of a single layer of oxide, nitride or carbide, or a multilayer of oxide, nitride and / or carbide! /.

In order to solve the above-described problems, the present invention provides a mold for optical elements or a mold for nanostructures having a nanostructure manufactured by a method for manufacturing a mold for optical elements.

[0020] In order to solve the above problems, the present invention has a nano-structure with fine irregularities on the substrate surface.

An optical element comprising a high-aspect-ratio nanopattern arranged randomly is provided.

[0021] Preferably, the nanopattern of the optical element having the nanostructure has a configuration in which an interval equal to or less than a wavelength of a light source is maintained.

The invention's effect

[0022] According to the present invention, the following effects occur.

(1) The optical element molding die according to the present invention has a nanostructure uniformly and stably on a substrate surface having a large area and a complicated free-form surface, and has a large area at a lower cost. High sensitivity sensor chips can be manufactured.

(2) The method for producing a mold for an optical element or nanostructure having a nanostructure according to the present invention can be produced by only a dry process with a small number of steps and high productivity.

Brief Description of Drawings

FIG. 1 is a diagram illustrating Example 1 of the present invention.

FIG. 2 is a diagram for explaining Example 1 of the present invention.

FIG. 3 is a diagram for explaining Example 1 of the present invention.

FIG. 4 is a diagram for explaining Example 2 of the present invention.

[Fig. 5] Injection molding using a mold for optical elements having the nanostructure of Example 1 of the present invention. It is a figure explaining manufacture of a form, shaping | molding of a nanostructure, and an optical element.

FIG. 6 is a diagram for explaining the production of an injection mold using the mold for an optical element having a nanostructure of Example 2 of the present invention, the molding of the optical element having a nanostructure, and the optical element. .

Explanation of symbols

1 Mold for optical elements with nanostructures

2 Board

3 Etching transfer layer

4 Thin films for the production of island-shaped fine particles

5 Island-like fine particles

6 Molds for optical elements with nanostructures

7 Board

8 Injection mold

9 Optical elements with nanostructures

10 Injection mold

11 Optical elements with nanostructures

BEST MODE FOR CARRYING OUT THE INVENTION

[0025] An optical element having a nanostructure according to the present invention or a mold for forming a nanostructure, a manufacturing method thereof, and a best mode for carrying out the optical element will be described below with reference to the drawings based on the embodiments. Explained.

The present invention is for an optical element or a nanostructure for molding an optical element having a fine uneven structure (nanostructure) on the surface for obtaining a highly sensitive sensing effect such as biotechnology or medical treatment. A mold and a manufacturing method thereof. The steps of the method for producing the molding die for optical elements according to the present invention are as follows.

(1) Thin film formation process on the substrate

A plurality of etching transfer layers are formed on the substrate, and a thin film is formed all at once. These forming steps are performed by a vacuum dry process.

[0027] (2) Formation of nanopattern Using the power of thermal reaction, photoreaction, gas reaction, or a composite reaction that combines two or more of these reactions, the thin film is caused to agglomerate, decompose, or nucleate, and the nanometer Ordered fine hemispherical island-shaped fine particles Force nano-patterns that exist randomly at intervals less than the wavelength of the target light source.

[0028] The substance that becomes the island-shaped fine particles is mainly a material mainly containing one of silver, gold, platinum, and radium, or one of silver, gold, platinum, palladium, tungsten, bismuth, and tellurium. By using an oxide material or nitride as a component, it is possible to form a nanopattern in which the interval between the plurality of island-shaped fine particles is narrow. At this time, the average particle size of the hemispherical island-shaped fine particles is 5 nm to 1 OOOnm, and the average interval between adjacent island-shaped fine particles is preferably 1 Onm to 200 Onm or less! /.

[0029] (3) Etching the etching transfer layer using the formed nano-pattern, that is, using the island-shaped fine particles as a protective mask, and finally etching to the target substrate, A nano-structure with a fine cone shape is formed on the substrate, and a mold for an optical element having a nano structure or a mold for a nano structure is produced.

[0030] In this case, as described above, a plurality of etching transfer layers are provided between the island-shaped substance and the substrate, so that an optical element including a nanostructure having a high aspect ratio can be molded. Concave and convex surfaces (nanostructure mold surfaces) can be efficiently produced on the surface of the mold for optical elements.

[0031] If this optical element mold is used, as will be described in the following examples, a nanostructure having a fine uneven surface on the surface of the substrate and arranged in a random manner has a high aspect ratio. Preferably, the nanopattern is an optical element having a nanopattern that is configured to maintain a distance equal to or smaller than the wavelength of the light source.

Example 1

Hereinafter, with reference to the drawings, Embodiment 1 of an optical element molding die and a manufacturing method thereof according to the present invention will be described in detail. FIG. 1 is a diagram for explaining the steps of a manufacturing method for manufacturing a mold 1 for an optical element according to Example 1 of the present invention using a reactive ion etching method.

[0033] (1) Using a film forming apparatus (not shown), the surface of the planar substrate 2 is composed of one or more layers. An etching transfer layer 3 and a thin film 4 for producing island-shaped fine particles are formed (FIG. 1 (a)). Based on a verification test, the inventors of the present invention randomly deposited island-like particles 5 on the surface of the substrate 2 on the surface of the substrate 2 at intervals less than the wavelength of the target light source. Confirm that it is effective as a material for the thin film 4 to form!

[0034] (2) Next, using the agglomeration action, the nucleation adoption, or the decomposition action, the island-like fine particles 5 arranged in the random space are produced at intervals equal to or shorter than the wavelength (FIG. 1 (b)). 2 (a) and 2 (b) are a cross-sectional view and a plan view showing island-shaped fine particles 5 formed on the substrate 2 and the etching transfer layer 3.

By the way, by using thermal reaction, light reaction, gas reaction and the like as parameters, the aggregation reaction and nucleation reaction of the material can be controlled to control the average particle diameter and interval of the island-shaped fine particles 5. It is possible. In addition, the present inventors have confirmed that the average particle diameter and interval of the island-shaped fine particles 5 can be controlled by adding impurities to the material of the thin film 4.

[0036] In addition, when an oxide mainly composed of any of silver, gold, platinum, palladium, tungsten, bismuth, and tellurium is used, by using heat, light, or gas decomposition action, It is possible to control the average particle size and interval of the island-shaped fine particles 5.

[0037] (3) Next, using the formed island-shaped fine particles 5 as a mask, a reactive gas (for example, CF, CH

Four

F, CH, CF, H, C0, NH, CI, BC1)

3 4 6 2 3 2 3

(Fig. L (c)). Here, the etching transfer layer 3 maintains the same shape as the island-shaped fine particles 5, is etched, and sequentially functions as a masking layer for the next etching transfer layer 3 or the substrate 2.

[0038] When the fine irregular surface (nanostructure type surface) 1 'having a substantially conical shape for forming the nanostructure on the surface of the optical element is formed on the surface of the substrate 2 using the island-shaped fine particles 5, As described above, by providing the etching transfer layer 3, it is possible to produce a substantially conical shape having a high aspect ratio structure. As a material for the etching transfer layer 3, for example, when island-like fine particles 5 mainly composed of silver are used as a masking layer, materials mainly composed of carbon, silicon, silicon oxide, silicon nitride, etc. are effective. is there.

Here, when the main component of the island-like fine particles 5 is silver, the etching transfer layer 3 is carbon, and the substrate 2 is quartz, the etching rate between the island-like fine particles 5 and the etching transfer layer 3 is “island-like”. Fine particle 5 Etching rate ”<<“ Etching rate of etching transfer layer 3 ”Reactive etching is performed using a gas species. Thereby, the island-shaped fine particles 5 generate a masking effect, and a pattern can be formed on the etching transfer layer 3.

[0040] Next, in the case of etching between the etching transfer layer 3 and the substrate 2, the gas type in which the etching rate ratio is "etching rate of the etching transfer layer 3" <<"etching rate of the substrate 2" Reactive etching using is performed. As a result, it is possible to produce a substantially cone-shaped nanostructure masked on the surface of the substrate 2 based on the island-shaped fine particles 5. Further, the etching transfer layer 3 does not need to be a single layer, and can be produced in multiple layers by a process design for etching.

[0041] A similar process is performed on the second and subsequent etching transfer layers 3 (FIG. 1 (d)). Finally, the substrate 2 is etched, and the surface of the substrate 2 is finely formed with a substantially conical shape. An optical element molding die 1 having an uneven surface (nanostructure mold surface) 1 ′ is formed (FIG. 1 (f)).

[0042] By using the above manufacturing method, the substrate 2 has a fine concavo-convex structure formed on the surface of the substrate 2 densely at intervals equal to or less than the wavelength of the target light source and randomly in a substantially conical shape only by a dry process. Things are possible. As a result, even an optical substrate having a complicated shape can be easily manufactured, and the manufacturing process can be simplified.

FIG. 3 shows a representative SEM image (scanning electron microscope image) of the island-shaped fine particles 5 obtained by the Example 1 of the present inventors. As a result, it was confirmed that island-shaped fine particles 5 could be randomly formed on the surface of the substrate 2 at intervals equal to or less than the wavelength of the target light source. In addition, from this SEM image, it was confirmed by Example 1 that the effective material for the thin film 4 is a substance mainly composed of silver.

[0044] In addition, through the demonstration test of Example 1, the inventors have realized control of the aggregation reaction and nucleation reaction of these materials by controlling the thermal reaction, photoreaction, or gas reaction, It was also confirmed that the average particle size and interval of the island-shaped fine particles 5 can be controlled. It was also confirmed that the average particle size and spacing of the island-shaped fine particles 5 can be controlled by adding impurities to these materials.

[0045] Further, when an oxide mainly composed of any of gold, platinum, palladium, tungsten, bismuth and tellurium is used as the thin film forming the island-shaped fine particles 5, heat, light Or, by using the gas decomposition action, I was confident that I was able to control the average particle size and spacing of the island-shaped fine particles 5.

[0046] The fluorescence intensity was measured using the optical element molding die 1 (not the optical element itself) produced using the optical element molding die 1 having the nanostructure manufactured according to Example 1. As a result, it was confirmed that the detection sensitivity could be improved 50 times in the presence of nanostructures compared to the case without nanostructures.

[0047] Because of this fact, the present invention can produce a substantially concave and convex surface (nanostructure-type surface) 1 'having a substantially conical shape on the surface of the substrate 2 only by a dry process, thereby reducing costs and productivity. I assured that this is an excellent method.

[0048] Further, as a material of the substrate 2, a resin such as quartz, glass, polycarbonate, PMMA, gallium nitride, gallium arsenide, indium phosphide, uckel, iron, titanium, carbon, sapphire, carbon nitride, or the like may be used. , Confirmed that there is a similar effect.

Example 2

[0049] Fig. 4 is a diagram for explaining a process for performing the manufacturing method of the optical element mold 6 according to Example 2 of the present invention using the reactive ion etching method in the same manner as in Example 1. . Example 2 relates to a molding die for an optical element that molds an optical element having a nanostructure on a substrate having a free-form surface, and the substrate 7 has a free-form surface and is different in its manufacturing method. Therefore, the description thereof is omitted.

[0050] In the mold 6 for an optical element having a nanostructure obtained by the manufacturing method according to Example 2, the surface of the substrate 6 is formed with a substantially conical fine uneven surface (nanostructure mold surface) 1 '. As for the reflection characteristics, the same effect as in Example 1 can be obtained.

[0051] (Method of manufacturing injection mold and molding of optical element having nanostructure)

Next, using the schematic diagram shown in FIG. 5, a method for producing an injection molding die from the optical element molding die 1 having the nanostructure described above will be described, and the nanostructure using this injection molding die An example of a mass production method of an optical element having a body will be described.

FIG. 5 (a) shows an optical element molding die 1 having a silicon nanostructure obtained in Example 1 of the present invention (an optical element molding die having a quartz glass nanostructure). 1 is acceptable. Using this mold 1 for optical elements having nanostructures made of silicon, Fig. 5 (b) As shown in FIG. 5, an injection mold 8 as shown in FIG. 5 (c) is produced by performing a normal nickel electroplating process.

Next, as shown in FIG. 5 (d) using the injection mold 8, the optical element 9 having the nanostructure as shown in FIG. 5 (e) is used using the injection mold 8. Can be mass-produced. This optical element 9 has a nano-structure with fine irregularities on the substrate surface and is provided with a high-aspect-ratio nano-pattern that is randomly arranged. Preferably, this nano-pattern has an interval less than the wavelength of the light source. It is an optical element provided with the nano pattern which is the structure maintained.

[0054] Specifically, the nanopattern of the optical element 9 is island-shaped, and the average diameter thereof is preferably 5 nm to 100 Onm, and the average interval between adjacent islands is preferably 10 nm to 2000 nm or less.

FIG. 6 is a diagram for explaining a method using the optical element mold 6 (see FIG. 6 (a)) having the nanostructure obtained in Example 2 of the present invention. This method is exactly the same as the method shown in FIG. 5, and an injection mold 10 (see FIG. 6 (c)) is created by performing a normal nickel electroplating process (see FIG. 6 (b)). .

[0056] Further, as shown in FIG. 6, an optical element having a nanostructure is injection-molded using the injection mold 10 (see FIG. 6 (d)). An optical element 11 with a body (see Fig. 6 (e)) can also be mass-produced.

Industrial applicability

[0057] Since the present invention has the above-described configuration, the optical element in general (for example, a projector lens, an optical pickup, a display, etc.), the light emitting element in general (for example, LED, laser, etc.), the light receiving element in general (photo (Applicable to diodes, solar cells, etc.), bioanalysis chips, thermal control plates, fluid sensors, and acceleration sensors.

Claims

The scope of the claims

[1] A method for producing a molding die for an optical element or a nanostructure for molding an optical element having a nano structure with fine irregularities on a substrate surface,

Forming one or more etching transfer layers on the substrate, forming a thin film for generating island-shaped fine particles on the etching transfer layer;

A plurality of island-shaped fine particles are produced by causing the thin film material to agglomerate, decompose, or nucleate using a thermal reaction, a light reaction, a chemical reaction, or a composite reaction thereof. Forming,

For an optical element having a nanostructure, characterized in that an etching transfer layer and the substrate are sequentially etched using the plurality of island-shaped fine particles as a protective mask to form a high aspect ratio pattern on a fine surface of the substrate. Or the manufacturing method of the shaping | molding die for nanostructures.

[2] The plurality of island-shaped particles are hemispherical, each having a nanometer order, and a nanopattern formed randomly arranged while maintaining an interval equal to or less than the wavelength of the target light source. The method for producing a mold for an optical element or a nanostructure having a nanostructure according to claim 1, wherein the mold is formed.

[3] The material of the thin film is mainly composed of a substance mainly composed of silver, gold, platinum, or palladium, or any component of silver, gold, platinum, palladium, tungsten, bismuth, and tellurium. 3. The method for producing a mold for an optical element or nanostructure having a nanostructure according to claim 1 or 2, wherein the mold is an oxide or a nitride.

[4] The island-shaped fine particles may have an average particle diameter of 5 nm or more;! OOOnm, and an average interval between the plurality of island-shaped fine particles may be 10 nm to 2000 nm. A method for producing a mold for an optical element or a nanostructure having the nanostructure according to item 1.

[5] The substrate is made of quartz glass, resin, silicon, gallium nitride, gallium arsenide, indium phosphide, nickel, iron, titanium, carbon, sapphire, or a metal or non-metal mainly composed of carbon nitride. A method for producing a mold for an optical element or a nanostructure having the nanostructure according to any one of claims 1 to 4.

[6] The etching transfer layer is composed of a single layer of oxide, nitride, or carbide, or a multilayer composed of any of oxide, nitride, and carbide. A method for producing a mold for an optical element or a nanostructure having the nanostructure according to any one of the above.

[7] An optical element- or nanostructure-forming mold having a nanostructure produced by the method for producing an optical element-molding mold according to any one of [1] to [6].

[8] An optical element characterized in that it has a nanopattern with a high aspect ratio, which is formed by randomly arranging nano-structures with fine irregularities on the substrate surface.

9. The optical element according to claim 8, wherein the nanopattern of the optical element having the nanostructure is configured to maintain an interval equal to or less than a wavelength of a light source.