CN101566699B - The manufacture method of antireflection material, optical element, display device and pressing mold and employ the manufacture method of antireflection material of pressing mold - Google Patents

Abstract

Antireflection material of the present invention is the antireflection material forming the little convex-concave pattern of the minimal wave length of its period ratio incident light on a surface of a substrate in x direction and y direction, when the minimal wave length of supposition incident light is λ _min, incident light maximum incident angle be θ i _max, incident medium cycle in refractive index to be cycle in x direction in ni, convex-concave pattern be Λ x and y direction when being Λ y, meet following formula (1), [mathematical expression 1] <maths num=" 0001 " > </maths> thereby, it is possible to suppress the generation of the diffraction light of short-wavelength light composition in wide wave band.

Description

The manufacture method of antireflection material, optical element, display device and pressing mold and employ the manufacture method of antireflection material of pressing mold

The application is the divisional application of following application,

Denomination of invention: the manufacture method of antireflection material, optical element, display device and pressing mold and employ the manufacture method of antireflection material of pressing mold

The applying date: on Dec 1st, 2005

Application number: 200580041596.9

Technical field

The present invention relates to the superior antireflection material of antireflective property and be equipped with optical element and the display device of this antireflection material.In addition, the manufacture method of the manufacture method that the invention still further relates to pressing mold (also referred to as " metal pattern " or " mold ") and the antireflection material employing pressing mold and antireflection material.

Background technology

In the optical element for the display device of TV and mobile phone etc. and camera lens etc., in order to reduce surface reflection to improve the transit dose of light, usually implement antireflection technology.This is because, such as, as the situation that light incides the interface of air and glass, when light passes through the interface of the different medium of refractive index, utilize Fresnel reflection etc. reduce the transit dose of light and reduce visual cause.

As antireflection technology, such as, can enumerate the method for the antireflection multilayer film of the multilayer film having arranged stacked on a surface of a substrate to be formed by organic fine particles such as inorganic particulate or acrylic acid such as silicon dioxide.But, because antireflection multilayer film is usually by film forming such as vacuum vapour depositions, so there is the problem that film formation time is long, cost is high.Particularly, under the environment that light is very strong around, owing to requiring higher antireflective property, so the stacked number of plies of antireflection multilayer film must be increased, cost is caused to rise further.In addition, because antireflection multilayer film utilizes the interference of light, so antireflection effect is strongly depend on incident angle and the wavelength of light.Therefore, once incident angle or wavelength exceed scope of design, then antireflection effect reduces significantly.

As other antireflection technology, can enumerate and be formed the method for the micro concavo-convex figure of concavo-convex periodic Control below the wavelength of visible ray (patent documentation 1 to patent documentation 5) on the surface of the substrate.This process employs the principle of so-called moth eye (Motheye) structure, by making the refractive index refractive index of the light incided on substrate being varied continuously to substrate along concavo-convex depth direction from the refractive index of incident medium, thus suppress the reflection for antireflecting wave band.As convex-concave pattern, exemplify the cone-shaped body such as circular cone or rectangular pyramid (with reference to patent documentation 3 to patent documentation 5).

With reference to Figure 11 (a) and (b), explain the antireflection effect caused because of the formation of micro concavo-convex figure.Figure 11 (a) schematically shows the sectional view defining the concavo-convex substrate of rectangle, and Figure 11 (b) schematically shows the sectional view defining the concavo-convex substrate of triangle.

First, with reference to Figure 11 (a).The substrate 1 defining the rectangle concavo-convex 2 as shown in Figure 11 (a) produces the effect same with the substrate defining single thin film.

At the beginning, the antireflection effect of single thin film is described simply.Such as, consider that defining wavelength on the glass substrate that thickness is the single thin film of d be the situation of the visible ray incidence of λ.Be zero to make the reflected light of vertical incidence light (incident angle=0 °), the reflected light that must be formed on the membrane surface carries out mutually the such single thin film of destructive interference with the reflected light of the interface at film and glass substrate.Specifically, the thickness d of single thin film and refractive index n can be set as d=λ/4n and n=(ni × ns) respectively ^1/2(assuming that the refractive index of air is ni, the refractive index of glass is ns).Refractive index ni due to air is 1.0, the refractive index ns of glass is about 1.5, so the refractive index n calculating single thin film is about 1.22.Therefore, in principle, be 1/4 wavelength place at thickness, by forming the single thin film that refractive index is about 1.22 on the surface of glass substrate, can inhibitory reflex completely., owing to being used in the refractive index of the organic system material of film up to about more than 1.5, even refractive index is less than the mineral-type materials of organic system material, also have an appointment about 1.3 refractive index, so reality is, such substrate cannot be formed.

Then, the antireflection effect in the fine rectangle concavo-convex 2 as shown in Figure 11 (a) is described.Now, by making concavo-convex cycle optimization, can play and define refractive index and be about the same effect of the situation of the single thin film of 1.22, can inhibitory reflex completely.But, in the same manner as the situation of single thin film, be difficult to play broadband antireflection effect or the antireflection effect little with incident angle dependency.

In contrast, as shown in Figure 11 (b), under concavo-convex shape is leg-of-mutton situation, owing to changing along concavo-convex depth direction, so reduce surface reflection to the refractive index of the light incided on substrate.In addition, when such as shown in Figure 11 (b) define convex-concave pattern, compared with above-mentioned antireflection multilayer film, except playing except wide wave band and the little antireflection effect of incident angle dependency, also have and be applicable to multiple material, on substrate, directly can form the advantages such as convex-concave pattern.Consequently, a kind of low cost, high performance antireflection material can be provided.

Usually; moth ocular structure is the pressing mold (metal pattern or mold) of the structure adopting the shape from the teeth outwards with the concaveconvex shape reversion making it fine; by pressing, injection moulding or casting process etc., the micro concavo-convex shape of stamper surface is copied and is produced on translucent resin etc.

In the past, as the manufacture method of pressing mold, be generally laser interference exposure method or electron beam (EB) exposure method.But, by these methods or large-area pressing mold cannot be made, or extremely difficult.

On the other hand, in patent documentation 6, disclose to adopt and aluminium is carried out anodic oxidation and the method for pressing mold produced at an easy rate in batches by anodic oxidation porous (porous) aluminium oxide that obtains.

Herein, the anodic oxidation Woelm Alumina obtained by aluminium is carried out anodic oxidation is described simply.So far, the manufacture method that make use of anodised cell structure is just noticeable as the simple and easy method of cylindric pore of the nanometer scale that can form ordered arrangement.As being immersed in the acidic electrolysis baths such as sulfuric acid, oxalic acid or phosphoric acid or alkaline electrolyte solution by matrix material, and apply voltage as anode, then can carry out being oxidized and dissolving on the surface of matrix material simultaneously, form punctulate oxide film thereon in its surface.Because this columned pore is to oxide film vertically orientation, (kind, temperature etc. of voltage, electrolytic solution) demonstrates the order of Ad hoc mode under certain conditions, so be expected to be applied to various functional material.

Anodic oxidation porous alumina layer 10 schematically as shown in figure 12, is made up of the structure cell 16 of the constant dimensions with pore 12 and restraining barrier 14.The shape of the structure cell 16 when the porous alumina layer made under specified conditions viewed from the direction vertical with face is roughly regular hexagon with regard to schematically.During structure cell 16, taking at two-dimensional directional with the arrangement of most high density filling viewed from the direction vertical with face.Each structure cell 16 wherein centre place has pore 12, and the arrangement of pore 12 has periodically.Herein, the arrangement of pore 12 has periodicity and refers to, viewed from the direction vertical with face time, just says from the geometry center of gravity (below, being only called " center of gravity ") of certain pore towards the vector summation of the respective center of gravity of the whole pores adjoined with this pore be zero.In the example shown in Figure 12, owing to having identical length from the center of gravity of certain pore 12 towards 6 vectors of the respective center of gravity of 6 adjacent pores 12, its direction is mutually each differs from 60 degree, so the summation of these vectors is zero.In the porous alumina layer of reality, if the summation of above-mentioned vector is less than 5% of vector total length, then can be judged as having periodically.Because porous alumina layer 10 is formed, so be formed on aluminium lamination 18 by carrying out anodic oxidation to the surface of aluminium.

The formation of structure cell 16 is results that local tunicle dissolves and grows, and bottom the pore being referred to as restraining barrier 14, dissolving and the growth of tunicle are carried out simultaneously.Now known, the size i.e. interval of adjacent pore 12 of structure cell 16 is equivalent to roughly 2 times of the thickness on restraining barrier 14, is roughly directly proportional to voltage during anodic oxidation.In addition we know, although the diameter of pore 12 depends on the kind, concentration, temperature etc. of electrolytic solution, about 1/3 of the size (length of the most long-diagonal of the structure cell 16 time viewed from the direction vertical with face) of structure cell 16 is generally.

In such Woelm Alumina, the pore generated under given conditions shows the order of height, and in addition, depending on the difference of condition, can form its order has the pore of entanglement to a certain degree to arrange.

Patent documentation 6 discloses a kind of method: as embodiment, and (1) adopts anodic oxidation Woelm Alumina etc. on Si wafer to be mask, by carrying out dry etching to Si wafer, Si wafer surface is formed fine concavo-convex.Also disclosing a kind of method in addition: (2) form anodic oxidation Woelm Alumina on the surface of Al plate, with this Woelm Alumina for mask, by carrying out dry etching to metal A l, being formed fine concavo-convex in its surface.Disclose a kind of method in addition: (3) form anodic oxidation Woelm Alumina on the surface of Al plate, carry out dry etching to this alumina layer, retain a part wherein, formed concavo-convex from the teeth outwards.

Patent documentation 1: special table 2001-517319 publication

Patent documentation 2: JP 2004-205990 publication

Patent documentation 3: JP 2004-287238 publication

Patent documentation 4: JP 2001-272505 publication

Patent documentation 5: JP 2002-286906 publication

Patent documentation 6: JP 2003-43203 publication

Non-patent literature 1: the people such as beneficial field, the 52nd applied physics relation associating oratorical contest, gives a lecture pre-original text collection (spring in 2005, SaitamaYu university) 30p-ZR-9, p.1112.

But antireflection technology described in patent documentation 1 to 5 has following problem.

The first, according to existing convex-concave pattern, owing to depending on incident angle and diffraction light based on short-wavelength light occurs in specific angle, so there is the visual problem reduced.Particularly, when the antireflection material defining micro concavo-convex figure is used in display device, there is bluish diffraction light etc., visual reduction.

The second, there is the problem insufficient to the antireflection effect of the reflection diffracting light of normal reflection and zero degree.Such as, if antireflection material to be used for the mobile display etc. that the strong open air of sunlight uses, then visually significantly to reduce.In order to improve antireflection effect, generally known, be advisable to increase the concavo-convex aspect ratio ratio of concavo-convex cycle (height with).From the viewpoint of batch production etc., convex-concave pattern is usually to adopt the replica method of metal pattern (pressing mold) to make.But the concavo-convex metal pattern made for the formation of aspect ratio is large is very difficult.In addition, the metal pattern that namely enable making is such, is also difficult to copy convex-concave pattern accurately.Consequently, if by copying makes antireflection material, then mostly can not get desired antireflection effect.

In addition; because the manufacture method of the pressing mold of above-mentioned disclosed in patent documentation 6 (1) ~ (3) have employed dry process; device that must be expensive; and be subject to the restriction of plant bulk, thus be difficult to the pressing mold making the special shape such as large-area pressing mold or roller (roll).

Summary of the invention

One of fundamental purpose of the present invention is, even if providing a kind of suppresses the generation of the diffraction light of short-wavelength light composition in wide ranges of incidence angles, also can prevent the generation of normal reflection and by copying makes and also can play the antireflection material of superior antireflection effect.

In addition, another object of the present invention is to, a kind of moulding die making method being also suitable for the pressing mold manufacturing large area or special shape is provided.Particularly, a kind of pressing mold and the manufacture method thereof that are suitable for being formed the surface relief structure of the antireflection material that make use of moth ocular structure is provided.

Antireflection material of the present invention is the antireflection material defining the little convex-concave pattern of the minimal wave length of its period ratio incident light on a surface of a substrate in x direction and y direction, when the minimal wave length of the above-mentioned incident light of supposition is λ _min, above-mentioned incident light maximum incident angle be θ i _max, incident medium cycle that refractive index is ni, the refractive index of above-mentioned antireflection material is ns, the cycle in x direction in above-mentioned convex-concave pattern is Λ x and y direction when being Λ y, meet following formula (1)

[mathematical expression 1]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\mathrm{ni}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(1\right)$

Be denoted as " Λ x, y " further, Λ x and Λ y is merged.

In certain embodiment, above-mentioned formula (1) also meets following formula (2)

[mathematical expression 2]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\max \{\mathrm{ni},\mathrm{ns}\}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(2\right)$

(in formula, max{ni, ns} mean the large side of refractive index among ni and ns).

In certain embodiment, when the coordinate axis of short transverse supposing above-mentioned convex-concave pattern be h axle, the peak of protuberance in above-mentioned convex-concave pattern is h=d, the minimum point of recess in above-mentioned convex-concave pattern is h=0 time, with the effective refractive index n of the function representation of h _effh () meets following formula (3).

In certain embodiment, above-mentioned effective refractive index n _effdifferential coefficient (the dn of (h) _eff(h)/dh) also meet following formula (4).

In certain embodiment, above-mentioned effective refractive index n _eff(h) and use following formula (5).

N _eff(h)＝{(n _eff(h＝0)-n _eff(h＝d))/d}×h+n _eff(h＝0)···(5)

The function N represented _effh () is upper at least on one point intersects, and meets following formula (6).

|N _eff(h)-n _eff(h)|≤|n _eff(h＝d)-n _eff(h＝0)|×0.2···(6)

In certain embodiment, when the coordinate axis of short transverse supposing above-mentioned convex-concave pattern be h axle, the peak of protuberance in above-mentioned convex-concave pattern is h=d, the minimum point of recess in above-mentioned convex-concave pattern is h=0 time, raised part goes up roughly on one point and connects with the xy face of h=d, and above-mentioned recess is gone up roughly on one point and connected with the xy face of h=0.

In certain embodiment, above-mentioned recess configures symmetrically relative to the xy face of h=d/2 and raised part.

In certain embodiment, the raised part of above-mentioned convex-concave pattern has step-like side.

Optical element of the present invention comprises above-mentioned arbitrary described antireflection material.

Display device of the present invention comprises above-mentioned optical element.

The manufacture method of pressing mold of the present invention is the manufacture method of the pressing mold on surface with minute concave-convex structure, it is characterized in that, comprise following operation: (a) prepares to comprise from the teeth outwards at least containing the operation of the matrix material of the aluminium lamination of more than aluminium 95 quality %; B () by carrying out anodic oxidation partly to above-mentioned aluminium lamination, thus forms the operation with the porous alumina layer of multiple fine concave portions; And (c) contacts with the etching agent of aluminium oxide by making above-mentioned porous alumina layer, thus make the operation that above-mentioned multiple fine concave portions of above-mentioned porous alumina layer expand, by alternately repeatedly carrying out above-mentioned operation (b) and (c), above-mentioned porous alumina layer forms multiple fine concave portions separately with step-like side.When above-mentioned aluminium lamination comprises the element beyond aluminium, ideally, more than 1 quality % is comprised and less than Ti and/or Si of 5 quality %.Above-mentioned aluminium lamination also can contain more than aluminium 99.99 quality %.

In certain embodiment, in the above-mentioned operation (b) of repeatedly carrying out and (c), last operation is above-mentioned operation (b).

In certain embodiment, the most deep of above-mentioned multiple fine concave portions is in fact a little.

In certain embodiment, the fine concave portions that the fine protuberance that above-mentioned multiple fine concave portions comprises more than 3 less than 6 is formed around.

In certain embodiment, above-mentioned matrix material in the substrate of above-mentioned aluminium lamination also containing metal level or the semiconductor layer with electric conductivity.As conductive metal, be advisable with platinum (Pt), gold (Au), silver (Ag) or copper (Cu).In addition, as conductive semiconductor layer, be advisable with silicon (Si).

In certain embodiment, above-mentioned metal level is formed by valve metal (ValveMetal).So-called valve metal, it is the general name of the oxidized metal of anode, in addition to aluminum, tantalum (Ta), niobium (Nb), Mo (molybdenum), titanium (Ti), hafnium (Hf), zirconium (Zr), zinc (Zn), tungsten (W), bismuth (Bi), antimony (Sb) is also comprised.Particularly, be advisable with tantalum (Ta), niobium (Nb), Mo (molybdenum), titanium (Ti), tungsten (W).

In certain embodiment, also comprise following operation: define above-mentioned multiple fine concave portions with above-mentioned step-like side on above-mentioned porous alumina layer after, form high rigidity metal level, make it to cover above-mentioned porous alumina layer.

In certain embodiment, also comprise following operation: define above-mentioned multiple fine concave portions with above-mentioned step-like side on above-mentioned porous alumina layer after, carry out surface treatment.

In certain embodiment, above-mentioned matrix material is cylindric or cylindric, and above-mentioned surface is the outer peripheral face of above-mentioned matrix material, and above-mentioned outer peripheral face is jointlessly formed above-mentioned multiple fine concave portions.

In certain embodiment, cylindrically, and above-mentioned surface is the inner peripheral surface of above-mentioned matrix material to above-mentioned matrix material, and above-mentioned inner peripheral surface is jointlessly formed above-mentioned multiple fine concave portions.

In certain embodiment, above-mentioned matrix material, under above-mentioned aluminium lamination, has another concaveconvex structure being greater than 780nm.

In certain embodiment, the distance of above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure has between adjacent fine concave portions is in the scope of more than 100nm below 200nm.

In certain embodiment, form above-mentioned fine concave portions, above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure is had is not periodically.

In certain embodiment, also comprise following operation: adopt the duplicate of the above-mentioned porous alumina layer being formed with above-mentioned multiple fine concave portions separately with step-like side or the surface structure replicating above-mentioned porous alumina layer to make metal stamping and pressing.

The manufacture method of antireflection material of the present invention uses pressing mold to manufacture the method for antireflection material, it is characterized in that, comprise: the operation manufacturing above-mentioned pressing mold by above-mentioned any one method; And copy the operation of minute concave-convex structure on above-mentioned surface of above-mentioned pressing mold.

Pressing mold of the present invention is the pressing mold from the teeth outwards with minute concave-convex structure, it is characterized in that, has: matrix material; Be arranged on aluminium lamination on above-mentioned matrix material, that at least contain more than aluminium 95 quality %; And the porous alumina layer be arranged on above-mentioned aluminium lamination, above-mentioned porous alumina layer has multiple fine concave portions of each own step-like side.When above-mentioned aluminium lamination comprises the element beyond aluminium, ideally, more than 1 quality % is comprised and less than Ti and/or Si of 5 quality %.Above-mentioned aluminium lamination also can contain more than aluminium 99.99 quality %.

In certain embodiment, the most deep of above-mentioned multiple fine concave portions is in fact a little.

In certain embodiment, the fine concave portions that the fine protuberance that above-mentioned multiple fine concave portions comprises more than 3 less than 6 is formed around.

In certain embodiment, above-mentioned matrix material in the substrate of above-mentioned aluminium lamination also containing metal level or the semiconductor layer with electric conductivity.

In certain embodiment, above-mentioned metal level is formed by valve metal.

In certain embodiment, also there is the high rigidity metal level covering above-mentioned porous alumina layer.

In certain embodiment, surface treatment is implemented to above-mentioned minute concave-convex structure.Surface treatment is such as the demoulding process etc. that replicability is improved.

In certain embodiment, above-mentioned matrix material is cylindric or cylindric, and above-mentioned surface is the outer peripheral face of above-mentioned matrix material, and above-mentioned outer peripheral face is jointlessly formed above-mentioned multiple fine concave portions.

In certain embodiment, cylindrically, and above-mentioned surface is the inner peripheral surface of above-mentioned matrix material to above-mentioned matrix material, and above-mentioned inner peripheral surface is jointlessly formed above-mentioned multiple fine concave portions.

In certain embodiment, above-mentioned matrix material, under above-mentioned aluminium lamination, has another concaveconvex structure being greater than 780nm.With in the antireflection material manufactured by this pressing mold, above-mentioned minute concave-convex structure presents anti-reflection function, and another concaveconvex structure above-mentioned presents anti-dazzle (anti-glare) function.

In certain embodiment, the distance of above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure has between adjacent fine concave portions is in the scope of more than 100nm below 200nm.Using in the antireflection material manufactured by this pressing mold, because the diffraction of reflected light is suppressed, from but desirable.

In certain embodiment, be configured to above-mentioned multiple fine concave portions not periodicity that above-mentioned minute concave-convex structure has.Using in the antireflection material manufactured by this pressing mold, because the diffraction of reflected light is suppressed, from but desirable.

Anti-reflective film of the present invention is the antireflection material from the teeth outwards with minute concave-convex structure, and above-mentioned minute concave-convex structure comprises the multiple fine protuberance separately with step-like side.

In certain embodiment, the fine protuberance that the fine concave portions that above-mentioned multiple fine protuberance comprises more than 3 less than 6 is formed around.

In certain embodiment, the distance between the arbitrary protuberance adjoined each other among the above-mentioned multiple fine protuberance of supposition is P, the minimal wave length of incident light is λ _min, above-mentioned incident light maximum incident angle be θ i _max, incident medium refractive index be ni, the refractive index of above-mentioned antireflection material is when being ns, meets following formula (1 ')

[mathematical expression 3]

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\mathrm{ni}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(1^{,}\right).$

In certain embodiment, above-mentioned formula (1 ') also meets following formula (2 ')

[mathematical expression 4]

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\max \{\mathrm{ni},\mathrm{ns}\}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(2^{,}\right)$

(in formula, max{ni, ns} mean the large side of refractive index among ni and ns).

Invention effect

According to the present invention, a kind of antireflection material little with incident angle dependency in wide wave band can be provided.In addition, according to the present invention, owing to suppressed sufficiently the generation of normal reflection, thus can provide a kind of be suitable for the environment that light is very strong around under the antireflection material of removable (mobile) equipment such as the mobile phone that uses etc.

In addition, according to the present invention, even if a kind of by copying can be provided to make the antireflection material that also can play superior antireflection effect.

According to the present invention, a kind of moulding die making method being also suitable for the pressing mold (such as roll) manufacturing large area or special shape can be provided.Fine concave portions due to pressing mold has step-like side, so relative surface area is wider, consequently, surface-treated effect is enhanced.

According to the present invention, can easily manufacture large-area antireflection material.In addition, multiple fine protuberance due to antireflection material of the present invention can have the step-like side of the wavelength much smaller than visible ray, so with have same pitch with height antireflection material compare, be not easy the reflection (reflection diffraction of 0 time) causing light.In addition, can be manufactured on fine multiple protuberances formed on the surface does not have periodic antireflection material, and such antireflection material is not easy the diffraction causing light.

Accompanying drawing explanation

Fig. 1 be represent on the substrate defining micro concavo-convex figure wavelength be the light of λ incident time the sectional view in path.

Fig. 2 (a) is the sectional view representing the situation that the transmission diffraction light of the reflection diffracting light of zero degree and transmission diffraction light and-1 time is propagated in antireflection material, and (b) is the sectional view representing the situation that the reflection diffracting light of zero degree and transmission diffraction light are propagated in antireflection material.

Fig. 3 is the stereographic map of the structure of the antireflection material schematically showing embodiments of the present invention 1.

Fig. 4 (a) is the curve map of the diffraction efficiency represented in antireflection material I, and (b) is the curve map of the diffraction efficiency represented in antireflection material II, and (c) is the curve map of the diffraction efficiency represented in antireflection material III.

Fig. 5 (a) be shown schematically in substrate surface on define the stereographic map of the structure of the antireflection material of cone, (b) be shown schematically in substrate surface on define the stereographic map of the structure of the antireflection material of rectangular pyramid.C () is the effective refractive index n represented in the antireflection material shown in (a) He (b) _effh the curve map of the relation of () and concavo-convex height (h/d), (d) is the curve map of the reflection diffraction efficiency of the zero degree represented in the antireflection material shown in (a) He (b) and the relation with the concavo-convex height (d/ λ) represented by the relation of the wavelength X with incident light.

Fig. 6 (a) to (e) is the stereographic map of the structure of the antireflection material (structure A is to structure E) schematically showing embodiments of the present invention 3.

Fig. 7 (a) represents that structure A is to the effective refractive index n in structure E _effthe curve map of the relation of (h) and concavo-convex height (h/d), b () is the figure projected to by the convex-concave pattern of structure A to structure E on xh face, (c) represents the curve map of structure A to the reflection diffraction efficiency of the zero degree in structure E and the relation with the concavo-convex height (d/ λ) represented by the relation of the wavelength X with incident light.

Fig. 8 (a) to (c) is the stereographic map of the structure of the antireflection material (structure F is to structure H) schematically showing embodiments of the present invention 4.

Fig. 9 (a) represents that structure F is to the effective refractive index n in structure H _effthe curve map of the relation of (h) and concavo-convex height (h/d), b () is the sectional view of the y=y ' plane along Fig. 8 (a) to (c), (c) represents the curve map of structure F to the reflection diffraction efficiency of the zero degree in structure H and the relation with the concavo-convex height (d/ λ) represented by the relation of the wavelength X with incident light.

Figure 10 (a) is the planimetric map seen from the top of protuberance in the convex-concave pattern of the structure A shown in Fig. 6 (b), b () is the planimetric map seen from the top of protuberance in the convex-concave pattern of the structure F shown in Fig. 8 (a), c () is the sectional view of the c-c along (b), (d) is the sectional view of the d-d along (b).

Figure 11 (a) is the sectional view schematically showing the concavo-convex substrate defining rectangle, and (b) schematically shows the sectional view defining leg-of-mutton concavo-convex substrate.

Figure 12 is the figure of the structure schematically showing porous alumina layer.

Figure 13 (a) ~ (g) is the schematic sectional view of the manufacture method of pressing mold for illustration of embodiments of the present invention.

Figure 14 (a) and (b) are the schematic diagram of the shape of the pore 12a representing the porous alumina layer 10a obtained by the manufacture method of the pressing mold of embodiments of the present invention.

Figure 15 (a) and (b) are the schematic diagram of the shape of the pore 12b representing the porous alumina layer 10b obtained by the manufacture method of the pressing mold of embodiments of the present invention.

Figure 16 (a) and (b) are the schematic diagram of the shape of the pore 12c representing the porous alumina layer 10c obtained by the manufacture method of the pressing mold of embodiments of the present invention.

Figure 17 (a) and (b) are after being shown schematically in and defining the pore 12a shown in Figure 14, then the figure of the structure of porous alumina layer 10a ' by obtaining with each operation repeating anodic oxidation and etching under same condition.

Figure 18 (a) and (b) are after schematically showing and each defining the porous alumina layer 10c shown in porous alumina layer 10b and Figure 16 shown in Figure 15, by repeat anodic oxidation operation and etching procedure under the condition suitably controlling pore formation volume and etch amount until the figure of the structure of the protuberance porous alumina layer 10b ' that becomes pointed projections and obtain and porous alumina layer 10c '.

Figure 19 is the schematic diagram forming the method for concaveconvex structure for illustration of the manufacture method of pressing mold of application embodiments of the present invention on the whole outer peripheral face of the matrix material 22a of roll.

Figure 20 is the schematic diagram forming the method for concaveconvex structure for illustration of the manufacture method of pressing mold of application embodiments of the present invention on the whole inner peripheral surface of the matrix material 22b of cylindrical shape.

Figure 21 is the figure of the electron micrograph of the concaveconvex structure of the stamper surface representing embodiments of the invention, and (a) represents the front elevation of concaveconvex structure, and (b) represents stereographic map, and (c) represents sectional view.

Figure 22 is the figure representing the result of observing the surface of the antireflection material of embodiments of the invention with scanning electron microscope, and (a) represents the SEM picture of about 63500 times, and (b) represents the SEM picture of about 36800 times.

Figure 23 is the curve map of the spectral reflectivity characteristic of the normal reflection light of the antireflection material representing embodiments of the invention.

Figure 24 (a) is the schematic diagram of the arrangement represented for the protuberance of simulating, b () is the figure of the form (without differential continuous side, the step-like side of 10 grades, the step-like side of 5 grades) of the side representing protuberance, (c) is the curve map of the wavelength dependency represented by simulating 0 diffraction efficiency (reflection efficiency) tried to achieve.

Symbol description

1 substrate

2 convex-concave patterns

3 antireflection material

4 rectangular pyramids

10 porous alumina layers

12 pores (fine recess)

14 restraining barriers

16 structure cells

18 aluminium laminations (Al layer)

Embodiment

(embodiment 1)

Below, with reference to accompanying drawing, the 1st embodiment of antireflection material of the present invention is described.The antireflection material of present embodiment is the antireflection material defining the little convex-concave pattern of the wavelength of its period ratio incident light on a surface of a substrate, when the minimal wave length of supposition incident light is λ _min, incident light maximum incident angle be θ i _max, incident medium refractive index be ni, the cycle in the refractive index of antireflection material to be cycle in x direction in ns, convex-concave pattern be Λ x and y direction is when being Λ y, meets following formula (1).Be denoted as " Λ x, y " further, Λ x and Λ y is merged.

[mathematical expression 5]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\mathrm{ni}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(1\right)$

Utilize the antireflection material of present embodiment, can suppress to depend on the generation of incident angle to the diffraction light of specific angular spread.

First, with reference to Fig. 1, illustrate that wavelength is the light of λ path when inciding the antireflection material defining micro concavo-convex figure.On Fig. 1, for convenience's sake, the structure of the antireflection material of convex-concave pattern having been carried out one dimension configuration is shown.Have again, when defining one dimension convex-concave pattern as shown in Figure 1, although see specific refractivity, when having two-dimentional convex-concave pattern between TE (electric field) pattern and TM (magnetic field) pattern, but can't see this species diversity, is isotropic.

As shown in Figure 1, when light incides antireflection material, reflection and transmission each process in, there occurs the diffraction light (reflection diffracting light and transmission diffraction light) of various number of times.As the refractive index supposing incident medium (herein for air) be ni, to define the refractive index of the antireflection material of convex-concave pattern be ns, then reflection diffracting light and transmission diffraction light defer to grating equation (TheGratingEquations), meet the relation of following formula (5-1) and following formula (5-2) separately.

[mathematical expression 6]

$\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;m}-\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;i}=m\frac{\mathrm{\&lambda;}}{\mathrm{\&Lambda;}}\&CenterDot;\&CenterDot;\&CenterDot;(5-1)$

[mathematical expression 7]

$\mathrm{ns}\&CenterDot;\sin \mathrm{\&theta;m}-\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;i}=m\frac{\mathrm{\&lambda;}}{\mathrm{\&Lambda;}}\&CenterDot;\&CenterDot;\&CenterDot;(5-2)$

In formula, m represent diffraction number of times (0, ± 1, ± the integers such as 2), λ represents the wavelength of incident light, Λ represents concavo-convex cycle, θ i represents incident angle, θ m represents the angle of diffraction of m time.The order of diffraction number of times shown in Fig. 1 represents, θ i and θ m is just with the direction of arrow shown in Fig. 1.

From these formula, the diffraction light of reflection and transmission, wavelength X all along with incident light is elongated, or shortens along with concavo-convex periods lambda, becomes fadout light (evanescentlight) (light do not propagated) from the higher diffraction light that diffraction number of times is large successively.Therefore, when the concavo-convex cycle is little far beyond the wavelength of incident light, due to one time, diffraction light also becomes fadout light, the diffraction light (transmission diffraction light and reflection diffracting light) of zero degree only occurs, therefore improves visuality.

If consider these contents, then the visual principal element reduced is considered to depend on short-wavelength light (indigo plant) that incidence angle θ i propagates to specific diffraction angle m in existing antireflection material-1 inferior reflection diffracting light that is main body.According to this viewpoint, above formula (1) is determined the condition for-1 inferior reflection diffracting light being all decided to be fadout light, only having zero degree diffraction light (normal reflection) to propagate by the present inventor.

But above formula (1) is the formula deciding the only condition that zero degree diffraction light is propagated with regard to reflecting with the relation of the wavelength X of concavo-convex periods lambda and reflected light, also has the situation of the diffraction light occurred beyond zero degree with regard to transmission.Once there is the transmission diffraction light etc. of-1 time, then there is the visual possibility reduced.

In order to ensure more superior visuality, ideally, reflection and the diffraction light about a transmission also propagation zero degree is not only.According to above formula (1), following formula (2) is determined for the condition that reflection diffracting light and the transmission diffraction light of zero degree are propagated.

[mathematical expression 8]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\max \{\mathrm{ni},\mathrm{ns}\}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(2\right)$

In formula, max{ni, ns} mean the large side of refractive index among ni or ns.

With reference to Fig. 2 (a) and Fig. 2 (b), illustrate by by concavo-convex periodic Control in above formula (1), preferably the scope of above formula (2), suppresses the situation of the generation of the diffraction light of-1 time.

Below, consider that wavelength is that the visible ray (λ=380nm ~ 780nm) of λ incides from all orientation (0 < θ i < 90 °) of (refractive index ni=1.0) air the substrate (refractive index defining convex-concave pattern ) on situation.

First, as shown in Fig. 2 (a), calculate according to above formula (1) and only suppress the reflection diffracting light of-1 time and make the condition that the reflection diffracting light of zero degree and transmission diffraction light are propagated.In above formula (1), once substitution θ i _max=90 °, ni=1.0, then derive following formula (7).

[mathematical expression 9]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{2}\&CenterDot;\&CenterDot;\&CenterDot;\left(7\right)$

That is, by concavo-convex periods lambda x and Λ y all being controlled, into 1/2 (namely less than 190nm) of the minimal wave length (λ min=380nm) less than incident light, the generation of the reflection diffracting light of-1 time can be prevented.

Secondly, as shown in Fig. 2 (b), calculate the reflection diffracting light not only suppressing-1 time according to above formula (2), also suppress the transmission diffraction light of-1 time, and make the condition that the reflection diffracting light of zero degree and transmission diffraction light are propagated.In above formula (2), once substitution θ i _max=90 °, ni=1.0, max{ni, ns}=1.5, then derive following formula (8).

[mathematical expression 10]

$\frac{\mathrm{\&Lambda;x},y}{{\mathrm{\&lambda;}}_{\min }}<\frac{2}{5}\&CenterDot;\&CenterDot;\&CenterDot;\left(8\right)$

That is, by concavo-convex periods lambda x and Λ y all being controlled, into 2/5 (namely less than 152nm) of the minimal wave length (λ min=380nm) less than incident light, also can prevent the generation of the transmission diffraction light of-1 time.Thus, the antireflection material that visuality is further enhanced can be realized.

Have again, in above-mentioned example, although calculate assuming that the minimal wave length λ min of visible ray is 380nm, due to for preventing the scope of the visible ray reflected different because applying the purposes etc. of antireflection material, so λ min can be set to suitable scope after considering these situations.

Such as, in above-mentioned example, prevent more than 400nm visible ray reflection situation (λ min=400nm) under, only make the condition of the reflection diffracting light disappearance of-1 time be, according to above formula (7), as long as Λ x and Λ y is all controlled into less than 200nm.On the other hand, the condition that the transmission diffraction light both sides of the reflection diffracting light of-1 time and-1 time are all disappeared is, according to above formula (8), as long as all controlled by Λ x and Λ y as less than 160nm.

Below, with reference to Fig. 3, the antireflection effect of the antireflection material of present embodiment is explained.

Fig. 3 is the stereographic map of the structure of the antireflection material schematically shown for present embodiment.As shown in Figure 3, on the surface of substrate 1, as convex-concave pattern, to form cycle in x direction be cycle in Λ x, y direction is the rectangular pyramid 4 in Λ y cycle.The height d of rectangular pyramid 4 is 380nm, and the refractive index defining the antireflection material 3 of rectangular pyramid 4 is 1.5.Herein, assuming that Λ x=Λ y=200nm, 180nm, 150nm (antireflection material I ~ III).

Wherein, antireflection material II (Λ x=Λ y=180nm) is although be meet the example that above formula (1) does not meet the present embodiment of above formula (2).By θ i _max=85 °, ni=1.0, λ min=380nm substitute into above formula (1) calculate the Λ x of antireflection material II and the value of Λ y, this calculated value is set to the scope meeting above formula (1).

Antireflection material III (Λ x=Λ y=150nm) is the preferred example of the present embodiment meeting above formula (2).By θ i _max=85 °, ni=1.0, λ min=380nm, max{ni, ns}=1.5 substitute into above formula (2) calculate the Λ x of antireflection material III and the value of Λ y, this calculated value is set to the scope meeting above formula (2).

In contrast, antireflection material I is any one comparative example not meeting above formula (1) and above formula (2).

Wavelength is that the visible ray (λ min=380nm) of λ incides in these antireflection material from roughly all orientation (0 < θ i < 85 °) of (refractive index ni=1.0) air, the simulation of the diffraction efficiency obtained by Vector Diffraction Theory, calculates the diffraction efficiency of each time.Although diffraction efficiency is calculated by Vector Diffraction Theory or scalar diffraction theory etc., but according to Vector Diffraction Theory, as in the present embodiment, even the concavo-convex cycle much smaller than the situation of the wavelength of incident light, also can try to achieve diffraction efficiency roughly exactly.In contrast, because scalar diffraction theory is only only applicable to the situation that the concavo-convex cycle is fully greater than the wavelength of incident light, therefore will not adopt in the present embodiment.Diffraction efficiency based on Vector Diffraction Theory can be calculated according to parameters such as the degree of polarization of incident light or incident angle, the cycle of convex-concave pattern, the refractive indexes of substrate.Details such as can refer to M.G.Moharam: " Coupled-WaveAnalysisofTwo-DimensionalDielectricGratings ", SPIE883 (1988), p8-11 etc.

In Fig. 4 (a) to (c), represent the diffraction efficiency in antireflection material I ~ III respectively.In each figure of Fig. 4 (a) to (c), the chart in left side is shown with and closes 0 time of reflection and the diffraction light of-1 time, and the chart on right side is shown with and closes 0 time of transmission and the diffraction light of-1 time.The diffraction efficiency of-1 time is suppressed to the situation being roughly 0% under all incident angles to mean and can realize superior antireflection effect at wide wave band.

When have employed the antireflection material I of the important document not meeting present embodiment, as shown in Fig. 4 (a), if incident angle is about 50 ° ~ more than 60 °, then reflection and transmission both sides, there is the diffraction light of-1 time.Particularly, if incident angle exceedes about 50 °, then the transmission diffraction light of-1 time sharply rises.Therefore known, in antireflection material I, the diffraction light of-1 time can not be suppressed completely.

In contrast, when have employed the antireflection material II meeting above formula (1), as shown in Fig. 4 (b), the reflection diffracting light of-1 time can not occur all completely under any incident angle.But, if incident angle exceedes about 60 °, then there is the transmission diffraction light of-1 time.

When have employed the antireflection material III meeting above formula (1) and above formula (2), as shown in Fig. 4 (c), the diffraction light of-1 time can not occur completely.

From above result, according to present embodiment, because no matter incident angle is how many, the diffraction light of-1 time all disappears, so can provide the antireflection material that a kind of visuality is superior.

(embodiment 2)

Then, the 2nd embodiment of antireflection material of the present invention is described.In the antireflection material of present embodiment for meeting above formula (1), preferably meet the antireflection material of the embodiment 1 of above formula (2), and the minimum point supposing the coordinate axis of the short transverse of the convex-concave pattern recess that to be the peak of protuberance in h axle, convex-concave pattern be in h=d, convex-concave pattern is when being h=0, with the effective refractive index n of the function representation of h _effh () also meets following formula (3).

Utilize the antireflection material of present embodiment, the generation of normal reflection (reflection diffracting light of zero degree) can be suppressed fully.

Effective refractive index is determined by the concavo-convex occupation rate (FillFactor) of occupying in incident medium (such as air etc.).The computing method of effective refractive index such as can refer to the people such as PLalanne, J.WodernOptics, Vol.43, No.10, P.2063 (1996) etc.The method adopting effective refractive index to design convex-concave pattern is as reproducing the short-cut method of diffraction phenomena of the convex-concave pattern of resolving difficulty and known roughly exactly.

In above formula (3), so-called " ", mean and be positioned at n _eff(h=0) in the scope of=ns ± 7%, so-called " ", mean and be positioned at n _eff(h=d) in the scope of=ni ± 7%.

As the concavo-convex shape meeting above formula (3), such as, the polygonal pyramids such as triangular pyramid, rectangular pyramid, pentagonal pyramid, hexagonal pyramid are exemplified.The side that polygonal pyramid is positioned at 1 point (summit) outside this bottom surface and bottom surface by polygonal bottom surface and linking and is formed is formed.According to the shape of bottom surface, be called triangular pyramid, rectangular pyramid etc.The shape of side is not particularly limited, and both can be the polygons such as the triangle as shown in Fig. 6 (a) described later, or can be again the shape beyond the polygon as shown in Fig. 6 (b) to (e) described later.

Described in patent documentation 3 to 5 described above, in order to improve antireflection effect, ideally, concavo-convex shape is made the cone-shaped such as circular cone or rectangular pyramid, it is believed that circular cone might as well, the polygonal pyramids such as rectangular pyramid might as well, can play the effect of same degree, but the present inventor expects in the present invention, in order to suppress the generation of the reflection diffracting light of zero degree, insufficient with circular cone, discovery must make the polygonal pyramids such as rectangular pyramid.That is, circular cone does not meet in above formula (3)

Below, with Fig. 5 (a) to (d), explain the anti-normal reflection effect of the antireflection material of present embodiment.Specifically, with regard to the antireflection material that concavo-convex shape is rectangular pyramid (meeting the example of above-mentioned (3)) or cone (not meeting the example of above-mentioned (3)), both effective refractive indexs and the reflection diffraction efficiency of zero degree are compared.

Fig. 5 (a) be shown schematically in substrate (not shown) surface on define the stereographic map of the structure of the antireflection material of cone, Fig. 5 (b) be shown schematically in substrate (not shown) surface on define the stereographic map of the structure of the antireflection material of rectangular pyramid.Antireflection material shown in Fig. 5 (a) and the antireflection material shown in Fig. 5 (b) are that concavo-convex shape is different, and the cycle of convex-concave pattern and height are identical.No matter which kind of antireflection material, all formed on a surface of a substrate by the periods lambda y=200nm in the periods lambda x=200nm in x direction, y direction, concavo-convex maximum height d form concavo-convex.The refractive index ns of antireflection material is 1.5.

The visible ray now studied at wavelength X=550nm to impinge perpendicularly on the effective refractive index n in the situation in these antireflection material respectively with incidence angle θ i=0 ° from (refractive index ni=1.0) air _effthe reflection diffraction efficiency (normal reflection rate) of (h) and zero degree.

Specifically, follow the method described in document of the people such as above-mentioned PLalanne, in the scope that concavo-convex height is 0 ((h/d)=0) to d ((h/d)=1.0), calculate the effective refractive index n with the function representation of h _eff(h).The simulation of the diffraction efficiency obtained by above-mentioned Vector Diffraction Theory, tries to achieve the reflection diffraction efficiency of zero degree in the scope that the concavo-convex height (d/ λ) represented with the relation of the wavelength X with incident light is 0.4 to 1.8.In Fig. 5 (c), represent effective refractive index, in Fig. 5 (d), represent the reflection diffraction efficiency of zero degree.

From Fig. 5 (d), by concavo-convex shape being made rectangular pyramid (in figure, representing with ■), as compared to cone (in figure, representing with zero), improve anti-normal reflection effect.In cone, even if the concavo-convex height that increase represents with (d/ λ) is (following, be sometimes referred to as standardization height), also the generation of the reflection diffracting light of zero degree cannot be made to disappear completely, and in rectangular pyramid, by being about 1.8 by standardization Altitude control, the generation of the reflection diffracting light of zero degree can be made roughly to disappear.Due to λ is set as 550nm, so in order to make the reflection diffracting light of zero degree roughly disappear, as long as concavo-convex height d is controlled in the scope of about 990nm.

Like this, make rectangular pyramid by concavo-convex shape is not made cone, improve anti-normal reflection performance, its reason is, with regard to effective refractive index n _eff(h=0), although cone does not meet above formula (3), rectangular pyramid meets the cause of above formula (3).As shown in Fig. 5 (c), n _eff((h/d)=1.0) are all roughly equal with ni, and in rectangular pyramid n _eff(h=0) consistent with ns (1.5) (in figure, representing with ■), on the other hand, n in cone _eff(h=0) 1.4 are about, less than ns (in figure, representing with zero).When rectangular pyramid, because the xy face at h=0 only exists rectangular pyramid, so n _eff(h=0) consistent with the refractive index (ns) of rectangular pyramid, and when cone, owing to there is cone and this two side of incident medium in the xy face of h=0, n _eff(h=0) determined, so be less than ns by the cone of this xy plane and the area ratio of incident medium.

Therefore known, in order to suppress the generation of the reflection diffracting light of zero degree, importantly to meet in addition, if met then contribute to reducing reflectivity.

(embodiment 3)

Then, the 3rd embodiment of antireflection material of the present invention is described.The antireflection material of present embodiment is for meeting the antireflection material of the embodiment 2 of above formula (3), effective refractive index n _eff(h) and use following formula (5)

N _eff(h)＝{(n _eff(h＝0)-n _eff(h＝d))/d}×h+n _eff(h＝0)···(5)

The function N represented _effh () is upper at least on one point intersects, but also meets following formula (6).

|N _eff(h)-n _eff(h)|≤|n _eff(h＝d)-n _eff(h＝0)|×0.2···(6)

According to present embodiment, even if make the standardization represented with (d/ λ) highly more be less than the antireflection material of embodiment 2, also normal reflection rate can be suppressed below 0.1%.

According to the above-mentioned important document specified in present embodiment, with the effective refractive index n of the concaveconvex shape of the function representation of concavo-convex height h _effh () goes up at least on one point with the concavo-convex height represented with above formula (5) is the function N of steady state value from slope in the gamut of 0 to d _effh () is intersected.In addition, as shown in above formula (6), function N _eff(h) and effective refractive index n _effh the refractive index of difference (absolute value) relative to substrate media of () and the specific refractivity (absolute value) of incident medium, be positioned at the scope within 20%.The present inventor expects in the present invention, and in order to suppress the generation of normal reflection fully, discovery must meet above-mentioned important document.

Below, with Fig. 6 (a) to (e) and Fig. 7 (a) to (c), the anti-normal reflection effect of the antireflection material of present embodiment is explained.Specifically, respectively relatively and the reflection diffraction efficiency of the effective refractive index studied in the rectangular pyramid of the various shapes shown in Fig. 6 (a) to (e) and zero degree.Below, respectively the antireflection material shown in Fig. 6 (a) to (e) is called that structure A is to structure E.Wherein, structure A has the shape identical with the rectangular pyramid shown in above-mentioned Fig. 5 (b).

In Fig. 7 (b), the figure projected to by the convex-concave pattern of structure A to structure E on xh face is shown.The refractive index of these structures is identical with the structure shown in Fig. 5 (b) with the cycle of convex-concave pattern.

With regard to these structures, study the effective refractive index n during incidence of vertical incidence light in the same manner as above-mentioned embodiment 2 _effthe reflection diffraction efficiency of (h) and zero degree.In Fig. 7 (a), represent effective refractive index, in Fig. 7 (c), represent the reflection diffraction efficiency of zero degree.

From Fig. 7 (c), structure D (in figure, using ◆ represent) is even if its anti-normal reflection performance is also best in structure A to structure E.As shown in Fig. 7 (a), structure D meets the above-mentioned important document specified in the present embodiment.In structure D, effective refractive index n _effh () exists , , these 3 upper function N _effh () is intersected.In addition, when structure D, although effective refractive index n _effh () be function N on above-mentioned 3 _effh () is intersected, but be not limited thereto, and intersects as long as upper wherein.

In detail, in structure D, the effective refractive index distribution in (h/d)=0 ~ 0.5 is pole-changing point with (h/d)=0.5, distributes symmetrical substantially with the effective refractive index in (h/d)=0.5 ~ 1.0.In structure D, as structure B described later or structure C, can't see the rate of change region that great changes will take place sharp of effective refractive index.In structure D, vicinity and near, gently form the region that the rate of change (tangent slope) of effective refractive index is smaller.

According to structure D, by controlling as about more than 1.2 (ideally about more than 1.4) by (d/ λ), generation 100% disappearance haply of the reflection diffracting light of zero degree can be made.Due to λ is set as 550nm, as long as so concavo-convex height d is controlled, in the scope of about 660nm (situations of (d/ λ)=1.2) ~ 770nm (situations of (d/ λ)=1.4), the reflection diffracting light of zero degree can be made to disappear completely haply.Therefore, by concavo-convex shape is made structure D, even if make the standardization represented with (d/ λ) highly be less than the antireflection material of embodiment 2, also can further improve anti-normal reflection effect.

Other structure except structure D is all the comparative example (with reference to Fig. 7 (a)) not meeting the above-mentioned important document specified in the present embodiment.Have the region of the rate of change change of effective refractive index in arbitrary scope that concavo-convex height (h/d) is 0 to d due to these structures, so compared with structure D, its anti-normal reflection effect reduces.Below, the anti-normal reflection effect in respective structure is described one by one.

Effective refractive index distribution (being in Fig. 7 (a)) in reference structure body A.In structure A, in the rate of change ratio of effective refractive index in the rate of change of effective refractive index slightly little.Like this, in the region that the change of effective refractive index is little relative to the change of concavo-convex height, as shown in Fig. 7 (c), the reflection diffraction efficiency of zero degree depends on concavo-convex height (d/ λ) and vibrates and go to zero.Occur to vibrate and the region of decaying in diffraction efficiency, be presumed to and there occurs the interference substantially same with single thin film, in order to play superior antireflection effect at wide wave band, standardization height (d/ λ) must be increased, thus reduce from the accuracy of repetition of metal pattern.

Then, effective refractive index distribution (being △ and * in Fig. 7 (a)) in reference structure body C and structure E.In structure C and structure E, near (situation of structure C) or the rate of change of the effective refractive index of neighbouring (situation of structure E) sharply rises.Like this, the region large relative to the change of concavo-convex height in the change of refractive index is deposited in case, and as shown in Fig. 7 (c), even if increase standardization height (d/ λ), the reflection diffraction efficiency of zero degree does not also go to zero.In such region, due to the generation of the same diffraction phenomena of the structure considered with the discontinuous interface that distributes from effective refractive index is formed, so the generation of normal reflection cannot be suppressed fully.

Structure B (being zero in Fig. 7 (a)) have concurrently the larger region of the rate of change of effective refractive index ( near) and smaller region ( ).Therefore, as shown in Fig. 7 (c), although the normal reflection rate of structure B depends on standardization height and vibrates and reduce, also do not go to zero even if increase concavo-convex height.

From above result, in order to play the antireflection effect that fully can suppress normal reflection at wide wave band, ideally, the rectangular pyramid meeting the above-mentioned important document specified in the present embodiment is made.

(embodiment 4)

Then, the 4th embodiment of antireflection material of the present invention is described.The antireflection material of present embodiment is, by any one antireflection material of above-mentioned embodiment 1 to 3, protuberance is gone up roughly on one point connect with the xy face of h=d, recess is gone up roughly on one point fetch formation mutually with the xy face of h=0.Ideally, recess configures symmetrically relative to the xy face of h=d/2 and protuberance.According to present embodiment, even if by copying makes, also can obtain meeting the antireflection material of the above-mentioned important document of regulation in embodiment 3 while meeting above formula (3), or be met the antireflection material of above formula (3) and following formula (4).

Herein, above formula (4) is described.Above formula (4) means that the differential coefficient (tangent slope) of the effective refractive index that the left side represents is consistent substantially with the mean value of the effective refractive index that the right represents.In other words, the changes delta n of effective refractive index is meaned _effrelative to ratio (the Δ n of the changes delta h of concavo-convex height h _eff/ Δ h) less constant in the gamut that concavo-convex height is 0 to d.

In this manual, so-called " meeting the situation of above formula (4) " refers to that the differential coefficient (left side) of effective refractive index is positioned at the ± situation of the scope of 20% relative to the mean value (the right) of effective refractive index.

In the present embodiment, even if make the viewpoint that also can form the superior convex-concave pattern of antireflection effect such with good precision from by copying to determine above-mentioned important document.As mentioned above, convex-concave pattern is usually to adopt the replica method of metal pattern to make, but the convex-concave pattern (antireflection material) formed with replica method is in the majority by the shape of pruning with the top of the bottom or protuberance that become recess.Such as, when antireflection material has the shape of above-mentioned structure B or structure C, because the rate of change of the effective refractive index in this antireflection material exists vicinity sharply increase, so there is the significantly reduced possibility of anti-normal reflection performance.Therefore, even if make desirable to provide a kind of by copying, the effective refractive index distribution of convex-concave pattern also can meet the above-mentioned important document of regulation or the antireflection material of above formula (4) in embodiment 3 while meeting above formula (3).

Below, with Fig. 8 (a) to (c) and Fig. 9 (a) to (c), the anti-normal reflection effect of the antireflection material of present embodiment is explained.Specifically, respectively relatively and the reflection diffraction efficiency of the effective refractive index that have studied in the antireflection material of the concaveconvex shape shown in Fig. 8 (a) to (c) and zero degree.In Fig. 8 (a) to (c), the concaveconvex shape of one-period part among the convex-concave pattern showing each antireflection material.Y=y ' plane in figure is the face comprising y=y ' among the face parallel with xh face.Below, respectively the antireflection material shown in Fig. 8 (a) to (c) is called that structure F is to structure H.

In Fig. 9 (b), the sectional view of the y=y ' plane along Fig. 8 (a) to (c) is shown.As a reference, the perspective view of structure A is remembered in the lump in Fig. 9 (b).Structure F is identical with structure A with refractive index to the cycle (Λ x and Λ y) of the convex-concave pattern in structure H, and Λ x=Λ y=200nm, refractive index ns is 1.5.Structure A is bottom surface is quadrilateral, side is leg-of-mutton rectangular pyramid, but structure F all configures relative to the xy face of h=d/2 and protuberance symmetrically to the recess in structure H.

Difference for the convex-concave pattern making the convex-concave pattern of structure A and structure F becomes more significantly object, in Figure 10 (a) and (b), the planimetric map along concavo-convex short transverse is shown respectively.Figure 10 (a) is the planimetric map seen from the top of protuberance in the convex-concave pattern of the structure A shown in Fig. 6 (a), and Figure 10 (b) is the planimetric map seen from the top of protuberance in the convex-concave pattern of the structure F shown in Fig. 8 (a).In addition, in structure F, the sectional view of the c-c along Figure 10 (b) has been shown in Figure 10 (c), the sectional view of the d-d along Figure 10 (b) has been shown in Figure 10 (d).As a reference, in Figure 10 (c) and (d), describe the sectional view of the structure A made in the same manner as the situation of structure F in the lump.Even if further, in the convex-concave pattern of structure G and structure H, also the figure identical with Figure 10 (b) to (d) can be obtained.

As shown in Figure 10 (b) to (d), in structure F, recess configures symmetrically relative to the xy face of h=d/2 and protuberance, and, protuberance is formed roughly on one point (to connect with the xy face of h=d for f) upper in figure, recess is formed roughly on one point (to connect with the xy face of h=0 for g) upper in figure, meets the important document determined in the present embodiment.In contrast, in structure A, as shown in Figure 10 (a), although (connect with the xy face of h=d for f) upper in figure, recess (bottom surface) does not meet the important document determined in the present embodiment to protuberance roughly on one point.

With regard to these antireflection material, in the same manner as above-mentioned embodiment 2, study the effective refractive index n during incidence of vertical incidence light respectively _effthe reflection diffraction efficiency of (h) and zero degree.Effective refractive index is shown in Fig. 9 (a), the reflection diffraction efficiency of zero degree has been shown in Fig. 9 (c).As a reference, in Fig. 9 (a) and (c), describe the reflection diffraction efficiency of effective refractive index in structure A and zero degree in the lump.

First, description architecture body F and G.As shown in Fig. 9 (a), because the effective refractive index in structure F and structure G is distributed in the important document all meeting above formula (3) and specify in embodiment 3 in the gamut of (h/d)=0 ~ 1.0, so anti-normal reflection superior performance (with reference to Fig. 9 (c)).In structure F and structure G, effective refractive index n _effh () exists , , these 3 upper function N _effh () is intersected.

In detail, the effective refractive index distribution in (h/d)=0 ~ 0.5 is pole-changing point with (h/d)=0.5, distributes symmetrical substantially with the effective refractive index in (h/d)=0.5 ~ 1.0.In structure F and structure G, as above-mentioned structure B or structure C, can't see the rate of change region that great changes will take place sharp of effective refractive index.In structure F and structure G, vicinity and near, gently form the region that the rate of change (tangent slope) of effective refractive index is smaller.

On the other hand, in structure H, in the gamut of (h/d)=0 ~ 1.0, the rate of change of effective refractive index is completely constant, meets above formula (3) and above formula (4).Consequently, anti-normal reflection superior performance (with reference to Fig. 9 (c)).According to structure H, even if make the standardization represented with (d/ λ) highly more be less than the antireflection material of embodiment 2, also normal reflection can be suppressed fully.

Below, illustrate with Figure 10 (a) and (b), according to structure F to structure H, even if by copying makes, the reason that effective refractive index distribution is also almost constant.Below, for convenience's sake, structure F and structure A is carried out comparative illustration.

As mentioned above, effective refractive index is determined by the area ratio of the concaveconvex shape medium on xy face and incident medium.When structure A, as shown in Figure 10 (a), the xy face of h=0 only there is structure A (bottom surface) exist.That is, in the xy face of h=0, it is believed that the boundary line of concaveconvex shape medium and incident medium exists with mesh, the effective refractive index of h=0 is consistent with the refractive index ns of concaveconvex shape medium., as by copying makes structure A, then in most cases cannot reproduce this boundary line with good precision, because boundary line is the 2 dimension regions with limited spread, so the area ratio/occupancy ratio of incident medium increases.Consequently, according to the area ratio/occupancy ratio in the xy face of h=0 and the effective refractive index calculated greatly reduce than ns.

In contrast, in structure F, as shown in Figure 10 (b), recess is gone up roughly on one point and is connected with the xy face of h=0 (for g) in figure.Even if by copying makes structure F, only have the minimum point of recess namely to put the expansion that g has 2 dimensions, the said circumstances that the change of the effective refractive index of h=0 is opened up with 2 dimensional expansions than boundary line is little.

Therefore, according to structure F, even if by copying makes, effective refractive index distribution is also almost constant, thus can obtain superior antireflection effect.

Then, according to Fig. 9 (c), structure F is explained to the anti-normal reflection effect in structure H.According to structure F (in figure, representing with zero), by concavo-convex height (d/ λ) is decided to be about 1.8, normal reflection rate can be made to be entirely zero.On the other hand, according to structure H (in figure, with-represent), by concavo-convex height (d/ λ) is decided to be about 0.8 ~ 0.9, normal reflection rate can be made to be roughly zero.According to structure G (in figure, represent with △), because the normal reflection rate be about in the scope of 0.6 ~ 1.3 at concavo-convex height (d/ λ) is less than 0.1%, constrained to lower compared with structure A, thus anti-normal reflection effect in the region that concavo-convex height is low is superior.

From above result, when wishing to get the highest anti-normal reflection effect, the shape especially making structure F is ideal situation.In addition, when reducing highly to come for playing strong anti-normal reflection effect with the standardization that (d/ λ) represents, the shape making structure H is useful.If consider the making easness etc. of metal pattern, ideally make the shape of structure H.This is because the protuberance of structure F and structure G and the front end of recess are acute angle, in contrast, because the protuberance of structure H and recess have curved shape, thus the metal pattern with desired shape is easily made.

Have again, in the present embodiment, even if make according to by copying and also can form the such viewpoint of the superior convex-concave pattern of antireflection effect with good precision, shape about protuberance and recess is defined as " protuberance is gone up roughly on one point and connected with the xy face of h=d; recess is gone up roughly on one point and connected with the xy face of h=0 ", but when the concaveconvex shape according to design can be made, but this condition might not be met.Such as, although not there is recess as structure H, show the structure that the effective refractive index identical with structure H distributes, but show superior antireflection effect same with structure H.

So far, the convex-concave pattern exemplified with the surface of antireflection material has periodic situation in x direction and y direction, but convex-concave pattern might not need to have periodicity at two dimensional surface (on xy face).

That supposes (or between recess) between arbitrarily adjacent protuberance is spaced apart P, with regard to above-mentioned periods lambda x or periods lambda y (Λ x, y) with regard to, if meet the following formula (1 ') and (2 ') that obtain by replacing Λ x, y with P in above-mentioned relation (above formula (1) and (2)), then can obtain same effect.Further, suppress the viewpoint of diffraction from the whole wave band (380nm ~ 780nm) at visible ray, ideally, between adjacent protuberance, the interval P of (or between recess) is positioned at the scope of more than 100nm below 200nm.

[mathematical expression 11]

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\mathrm{ni}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(1^{,}\right)$

[mathematical expression 12]

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\max \{\mathrm{ni},\mathrm{ns}\}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}\&CenterDot;\&CenterDot;\&CenterDot;\left(2^{,}\right)$

In addition, assuming that the coordinate axis of the short transverse of convex-concave pattern is h axle, due to about with the effective refractive index n of the function representation of h _effh the above-mentioned relation (such as the relation of above formula (3) ~ (6)) of () has nothing to do with the presence or absence of the two-dimensional and periodic of convex-concave pattern, thus former state can be suitable for above-mentioned explanation.

Further, above-mentioned anti-reflective film such as can make of the replica method that have employed pressing mold.Particularly, if utilize the formation method of the following anodic oxidation Woelm Alumina that will illustrate, then large-area pressing mold can be manufactured with comparalive ease.In the following description, the example being formed and have the multiple fine recess of step-like side is described, but also can forms the recess with smooth flanks.

Then, the manufacture method of the pressing mold of embodiments of the present invention is described.

The present inventor uses the formation method of anodic oxidation Woelm Alumina, have studied the moulding die making method of the manufacture of the pressing mold being also suitable for large area or special shape.Because anode oxidation alumina can use wet processing (wetprocess) to be formed, as long as so can the matrix material with aluminium lamination be immersed in electrolytic solution or etching solution etc., without the need to vacuum technology, thus have not too by the advantage of the restrictions such as plant bulk.In addition, if matrix material can be immersed in electrolytic solution or etching solution, then the impact of matrix material shape is not vulnerable to, so also the pressing mold of the special shapes such as roller can be manufactured.

But if antianode oxidized porous aluminium oxide carries out wet etching, then the entirety (structure cell wall and restraining barrier) of aluminium oxide pore is etched with isotropy, be difficult to control concavo-convex shape.Such as, the surface of anti-reflective film is difficult to the fine concaveconvex structure obtaining preferable shape.

In order to control concavo-convex shape, any technique forming Anisotropic shapes must be adopted.Therefore, the present inventor is conceived in the phenomenon vertical direction of substrate being formed to the pore (fine recess) in anodic oxidation Woelm Alumina.That is, the forming process of this pore itself has very large anisotropy.In addition, anodic oxidation Woelm Alumina has following feature: once carry out anodic oxidation under the same conditions again after stopping anodic oxidation, the bottom of the pore formed in then former process becomes starting point, again forms identical unit cell dimension and the pore in aperture in identical position.If use the manufacture method of pressing mold of the present invention, these features then can be utilized to manufacture a kind of pressing mold, this pressing mold is such as used to make the antireflection material including the surface with minute concave-convex structure, and wherein, minute concave-convex structure has high antireflective property.

The manufacture method of the pressing mold of embodiments of the present invention is a kind of manufacture methods from the teeth outwards with the pressing mold of minute concave-convex structure, comprises following operation: (a) prepares to comprise from the teeth outwards at least containing the operation of the matrix material of the aluminium lamination of more than aluminium 95 quality %; B (), by carrying out anodic oxidation partly to aluminium lamination, forms the operation with the porous alumina layer of multiple fine concave portions; And (c) contacts with the etching agent of aluminium oxide by making porous alumina layer, make the operation that multiple fine concave portions of porous alumina layer expand, by alternately repeatedly carrying out operation (b) and (c), porous alumina layer forms multiple fine concave portions separately with step-like side.

Herein, the manufacture method of the pressing mold of embodiments of the present invention is one of its feature to form multiple fine concave portions with step-like side.Be separated by not far nearest, in non-patent literature 1, disclosing by repeating anodizing of aluminium and bore expands process, making the content with the anode oxidation alumina of various shape.In addition, according to non-patent literature 1, to form the non-aluminium oxide hanging the coniform pore of bell is mold, and adopt PMMA to make the antireflection material with moth ocular structure, the reflectivity of this antireflection material is about less than 1%.But the side of the recess formed in the alumina layer described in non-patent literature 1 is level and smooth (continuous print), and is orthoscopic.

In contrast, in the pressing mold of embodiments of the present invention, fine concave portions has step-like side, so relative surface area is roomy, consequently, surface-treated effect is enhanced.Such as, by applying demoulding process to the surface of pressing mold, improve replicability.In addition, apply waterproof and anti-oil processing (such as fluorine process) by the surface of antagonistic reflex material, can preventing polluting effect be obtained.In addition, its fine protuberance of the antireflection material obtained owing to using this pressing mold has step-like side, thus with have same pitch with height antireflection material compare, there is the feature of the reflection (0 diffraction) being not easy to cause light.

Have again, in this manual, the concaveconvex shape of so-called stamper surface, refers to by means of the degree of depth of arrangement cycle of the multiple recesses in concaveconvex structure or recess, aperture area, also has aspect ratio (ratio to the degree of depth of openings of sizes) etc. and give the shape of feature.The size of recess opening such as can represent with the diameter being similar to bowlder of the same area.In addition, the concaveconvex structure shape on the surface of the so-called antireflection material made by replica stamper, is referred to by means of the height of arrangement cycle of the multiple protuberances in concaveconvex structure or protuberance, floorage, also has aspect ratio (ratio to the height of bottom surface size) etc. and give the shape of feature.The size of protuberance bottom surface such as can represent with the diameter being similar to bowlder of the same area.Herein, by the reason that the shape of concaveconvex structure carries out showing with form as above be, in the manufacture method of pressing mold adopting anode oxidation alumina, what directly carry out controlling is the cause of the plurality of recess (in antireflection material, replicating the protuberance of the recess of pressing mold).

Below, with reference to Figure 13, the manufacture method of the pressing mold of embodiments of the present invention is described.

First, as shown in Figure 13 (a), prepare the matrix material comprising aluminium lamination (Al layer) 18 from the teeth outwards.Herein, for simplicity, illustrate only aluminium lamination 18.In addition, when adopting insulativity material (such as glass) as matrix material, ideally, the substrate of aluminium lamination 18 forms metal level or the semiconductor layer with electric conductivity.This is because be formed uniformly pore (fine recess) by anodic oxidation.As conductive metal, be advisable with valve metal.Valve metal is the general name of anodized metal, in addition to aluminum, tantalum (Ta), niobium (Nb), Mo (molybdenum), titanium (Ti), hafnium (Hf), zirconium (Zr), zinc (Zn), tungsten (W), bismuth (Bi), antimony (Sb) is also comprised.Particularly, be advisable with tantalum (Ta), niobium (Nb), Mo (molybdenum), titanium (Ti), tungsten (W).In addition, as semiconductor, be advisable with silicon (Si).Even if due to the semiconductor such as valve metal and Si in anodised process with electrolyte contacts, also can not produce bubble, thus do not cause peel off and destroy when Absorbable organic halogens form oxide film thereon.

In the following description, illustrate the situation of Al layer 18 containing more than aluminium 99.99 quality %, but such as described in patent documentation 6, Al layer 18 also can comprise the element beyond aluminium.Now, to be advisable less than 5 quality % at more than 1 quality % containing Ti and/or Si.Because Si and Ti is difficult to and Al solid solution, so when forming Al layer 18 by vacuum vapour deposition etc., it act as and suppresses Al grain growth, thus has the advantage of the Al layer 18 that can obtain flat surfaces.In addition, except the method known by vacuum vapour deposition or melting Alplate method etc. is formed except Al layer 18, also available aluminum substrate metal forms matrix material itself.

Ideally, in advance by the surface planarisation of Al layer 18.Such as, the available electric field grinding etc. taking the mixed solution of perchloric acid and ethanol makes it planarization.This is because the generation of the pore of the flatness antianode oxidized porous aluminium oxide on the surface of Al layer 18 has an impact.

Then, as shown in Figure 13 (b), by under defined terms to this Al layer 18 partly (surface portion) carry out anodic oxidation, formed porous alumina layer 10 '.By means of anodised condition (kind of such as formation voltage, electrolytic solution, concentration, in addition anodizing time etc.), the size of pore can be controlled, generate the degree of depth etc. of density, pore.In addition, by controlling the size of formation voltage, the order of pore arrangement can be controlled.Such as, for obtaining the condition of the high arrangement of order be: (1) carries out anodic oxidation by the liquid-solid suitable constant voltage had of electrolysis; And (2) carry out anodic oxidation for a long time.The combination of known electrolytic solution now and formation voltage is: be 28V in sulfuric acid, being 40V in oxalic acid, is 195V in phosphoric acid.

In the porous alumina layer 10 ' that the starting stage generates, due to the trend being arranged with generation entanglement of pore, so as considered repeatability, then as shown in Figure 13 (c), ideally, the initial porous alumina layer 10 ' formed of removing.In addition, from the viewpoint of repeatability, the thickness of porous alumina layer 10 ' is advisable with more than 200nm, from the viewpoint of throughput rate, is advisable with below 2000nm.

Certainly, as required, also can not remove porous alumina layer 10 ', and carry out the later operation of following operation (e) ~ (g) that will illustrate.In addition, in Figure 13 (c), show and remove the example of porous alumina layer 10 ' completely, but (such as from surface to certain degree of depth) removing porous alumina layer 10 ' also can partly.The removing of porous alumina layer 10 ' such as can be used in phosphate aqueous solution or chromium phosphoric acid mixed liquor and makes it to flood the stipulated time and method that removing etc. are known is carried out.

Thereafter, as shown in Figure 13 (d), again carry out anodic oxidation, form the porous alumina layer 10 with pore 12.By controlling anodised condition and time, controlling the size of pore, generating density, the degree of depth of pore, the order etc. of arrangement.

Then, as shown in Figure 13 (e), by carrying out the etching of ormal weight by means of making the porous alumina layer 10 with pore 12 contact with the etching agent of aluminium oxide, the borehole enlargement of pore 12 is made.Herein, by adopting wet etching, isotropy mode can be shown greatly to expand porous wall and restraining barrier.By adjusting the kind of etching liquid, concentration and etching time, etch amount (that is, the size of pore 12 and the degree of depth) can be controlled.Such as, in phosphate aqueous solution or chromium phosphoric acid mixed liquor, make it the dipping stipulated time and remove.

Thereafter, as shown in Figure 13 (f), again by carrying out anodic oxidation partly to Al layer 18, while depth direction makes pore 12 grow, thicken porous alumina layer 10.Herein, because the growth of pore 12 is from the bottom of established pore 12, so the side of pore 12 is step-like.

Again, as shown in Figure 13 (g), by again carrying out etching the aperture expanding pore 12 further by means of making porous alumina layer 10 contact with the etching agent of aluminium oxide.

Like this, by repeating above-mentioned anodic oxidation operation (Figure 13 (d)) and etching procedure (Figure 13 (e)), obtain comprising the porous alumina layer 10 of the pore (fine recess) 12 with desired concaveconvex shape.By suitably setting the respective process conditions of anodic oxidation operation and etching procedure, can control pore 12 size, generate density, pore the degree of depth while, also can control the step shape of the side of pore 12.Further, the bottom in order to reduce pore 12, be advisable to end at anodic oxidation operation (not carrying out etching procedure thereafter).

Herein, describe the example of hocket anodic oxidation operation and etching procedure, but between anodic oxidation operation and etching procedure, or between etching procedure and anodic oxidation operation, carry out matting or also can carrying out drying process thereafter.

The manufacture method of the pressing mold of embodiments of the present invention is such as suitable for the manufacture of the antireflection material with moth ocular structure.Herein, the concaveconvex shape of the antireflection material that antireflective property is high is described.

For above-mentioned embodiment 1 ~ 4, as mentioned above, the antireflective property that have employed the antireflection material of concaveconvex structure depends on concaveconvex shape.Continuity and concavo-convex height (or aspect ratio) the antagonistic reflex performance of the change of the effective refractive index at incident medium (air etc.) and the interface of concaveconvex structure body and the interface of concaveconvex structure body and matrix material have a great impact.The interface of incident medium and concaveconvex structure body and the interface of concaveconvex structure body and matrix material preferably point, the area of contact portion is advisable with little.In addition, concavo-convex shape itself, namely the effective refractive index distribution antagonistic reflex performance of jog also has an impact.

Further, in order to suppress the generation of diffraction light, ideally, the recess in concaveconvex structure or the arrangement of protuberance do not have periodically.What is called does not have periodically, refers to if be more than 5% of vector total length from the center of gravity of certain pore towards the vector summation of the whole pores center of gravity separately adjoined with this pore, then can say and not have in fact periodically.In addition, under concaveconvex structure has periodic situation, ideally, its cycle is less than the wavelength of light.In addition, from the viewpoint suppressing diffraction in the whole wave band (380nm ~ 780nm) of visible ray, ideally, the interval (interval of protuberance adjacent in antireflection material) of adjacent recess is positioned at the scope of more than 100nm below 200nm.

Therefore, with regard to the pressing mold for the formation of antireflection material, as long as make the shape or this shape itself that control the desired concaveconvex shape reversion making antireflective property high of the contributive each factor of antireflective property as described above (factor) on the surface of matrix material.

Substrate material surface defines antireflective property high desired by concaveconvex shape itself, such as, make the metal stamping and pressing (such as Ni pressing mold) replicating the surface relief structure of above-mentioned alumina layer of electrocasting, and adopt this metal stamping and pressing by copying to make antireflection material.The technology that the making of Ni electroforming pressing mold etc. can suitably use electroplating method and electroless plating method etc. to know.In addition, the surface of matrix material has made make antireflective property high desired by concaveconvex shape reversed shape, by its former state be used as antireflection material make pressing mold.When former state uses as pressing mold when intensity deficiency, such as, the layer that the stacked material high by hardness such as Ni or W is formed on the surface with concaveconvex structure.

Certainly, the duplicate of the surface relief structure replicating above-mentioned alumina layer is copied again, also can make the metal stamping and pressing with the surface structure identical with the surface relief structure of alumina layer.

Then, with reference to Figure 14 ~ Figure 18, the example of the shape of the pore (fine recess) 12 of the porous alumina layer 10 that the manufacture method of the pressing mold of explanation embodiments of the present invention obtains.

As shown in Figure 14 (a) He (b), by repeating respectively at identical conditions to carry out the operation (Figure 13 (d)) of pore formation with anodic oxidation at depth direction (arrow A 1) and expand the operation (Figure 13 (e)) in aperture to be etched in direction in aluminium oxide aspect (arrow A 2), form the pore 12a of the repetition had by constant differential (highly) (3 little lattice parts) and width (1 little lattice part) and the step profile formed.If repeatedly repeat anodic oxidation operation and etching procedure with short interval, then as shown in the figure, can obtain roughly in cone shape pore 12a.In addition, place like this is illustrative, by ending at anodic oxidation operation, to reduce the area bottom pore 12a, can obtain the pore 12a that most deep is in fact point.

If application the present invention, then can easily control improving the important above-mentioned factor of antireflective property.First, determine that concaveconvex structure cycle of occurring with or without unwanted diffraction light and pore interval can control with formation voltage during anodic oxidation.Or, by making to make under the condition that changes into of the periodicity generation entanglement of pore (departing from the condition of the condition obtaining the high film of above-mentioned periodicity), the generation not needing diffraction light also can be eliminated.In addition, the degree of depth (aspect ratio) of concaveconvex structure, can control by anodised pore formation volume and etch amount.

Such as, as shown in figure 14, if make pore formation volume (degree of depth) larger than etch amount (size of opening), then the concaveconvex structure of high aspect ratio is formed.In raising antireflective property, the height (degree of depth) of the concaveconvex structure of antireflection material is most important.In addition, like this when having the pore 12a of step-like side, if the size of step (differential and width) is less than wavelength, even if then the arrangement of pore 12a has periodically, compared with the antireflection material with same pitch, be also not easy the diffraction (reflection) causing light.

With reference to Figure 24, show by being made up of antireflection material the protuberance with step-like side to suppress the situation of diffraction.Figure 24 (a) is the schematic diagram of the arrangement represented for the protuberance of simulating, to be the figure of the form (without differential continuous side, the step-like side of 10 grades, the step-like side of 5 grades) representing protuberance side, Figure 24 (c) be Figure 24 (b) represents the curve map of the wavelength dependency by simulating 0 diffraction efficiency (reflection efficiency) tried to achieve.Except 10 grades, 5 grades, also 4 grades, 6 grades and 7 grades are also simulated.

As shown in Figure 24 (a), herein, to be highly 500 μm, the reflecting member of a length of side of square bottom surface to be the protuberance of the tetrapyamid shape of 200 μm be periodic arrangement is studied.From Figure 24 (c), when the differential wavelength much smaller than visible ray (380nm ~ 780nm) of side step, with have same pitch with height antireflection material compare, be not easy the reflection (0 diffraction) causing light.That is, when the number of steps in side is more than 5 (differential is below 100nm), anti-reflection effect is strong, and particularly, when number of steps is 5 ~ 6, in the wide region of visible ray, anti-reflection effect is strong.But also depend on the height etc. of the concaveconvex structure of antireflection material due to reflection efficiency, so suitably can set best number of steps, but by having step-like side, antireflection efficiency is improved.In addition, under the arrangement of protuberance does not have periodic situation, the wavelength dependency of antireflection efficiency reduces further, can obtain high anti-reflection effect in wide wavelength coverage.

By adjusting pore formation volume in the anodic oxidation operation of repeatedly carrying out and etching procedure and etch amount, the shape of concaveconvex structure itself can be controlled.

Such as, the porous alumina layer 10b as shown in Figure 15 (a) He (b), the pore 12b with stepped shape and this stepped shape can be formed and have more dark milder differential.Further, to have changed into severity control that the time carries out pore formation not only easily but also good.Its reason is, in order to at the bottom of the pore formed for starting point forms pore again in identical position, preferably make kind or the conditions constant such as concentration, temperature of anodic oxidation voltage in each anodic oxidation operation and electric field solution.In addition, etch amount can be controlled by the kind of each etching solution or temperature, concentration and etching time etc.In addition, by strong for the dissolving powers such as sulfuric acid used for electrolyte in anodised situation, also electrolytic solution when not applying voltage can be used as etching solution.

As mentioned above, in order to obtain high antireflective property, ideally, improve the continuity of the effective refractive index at incident medium and the interface of concaveconvex structure body and the interface of concaveconvex structure body and matrix material, make the area of contact portion minimum.That is, in the concaveconvex structure of the pressing mold for making antireflection material with replica method, ideally, recess and protuberance are all sharp-pointed shape, are in fact a little.

The manufacture method of pressing mold according to the embodiment of the present invention, because the pore formed with anodic oxidation is recess, so as illustrated in Figure 14 and Figure 15, by not carrying out etching procedure after anodic oxidation operation, the area bottom pore can be made to be Min..

In addition, the porous alumina layer 10c as shown in Figure 16 (a) He (b), the pore 12c of further sharpening can be formed.That is, according to present embodiment, the pore 12c with stepped shape and this stepped shape can be formed and have more dark more precipitous differential.Further, differential low than its previous stage of the most deep of pore 12c differential, but be certainly not limited thereto, form higher differentially also can.

Then, with reference to Figure 17 (a) and (b), the sharpening of the protuberance (recess of antireflection material) of the concaveconvex structure of pressing mold is described.

Figure 17 (a) and (b) illustrate, after defining the pore 12a shown in Figure 14, also by repeating the porous alumina layer 10a ' that anodic oxidation obtains with each operation of etching (but final operation is anodic oxidation operation) at identical conditions.Like this, by repeating anodic oxidation operation and etching procedure, expand the pore 12a roughly in cone shape, the final part retained farthest away from the center of each pore 12a ', forms pointed projections (summit).In fig. 17, show the example of pore 12a ' ordered arrangement, even if but when not having order, by repeating anodic oxidation operation and etching procedure, also in the part at the center farthest away from each pore 12a ', finally pointed projections can be formed.Like this, method according to the embodiment of the present invention, can make the pressing mold with concaveconvex structure, and recess and the protuberance of this concaveconvex structure are sharp shape.

As the feature of the concaveconvex structure made by this method, as shown in Figure 17 (b), around point (pore center) at the bottom of, there are 3 to 6 pointed projections (summit).In addition, there is depression (saddle) between these summit and summits.

Illustrate respectively in Figure 18 (a) and (b), after defining the porous alumina layer 10c shown in porous alumina layer 10b and Figure 16 shown in Figure 15, by under the condition suitably controlling pore formation volume and etch amount, till the pointed projection of protuberance, repeat porous alumina layer 10b ' that anodic oxidation operation and etching procedure (but final operation is anodic oxidation operation) obtain and porous alumina layer 10c '.

Like this, by regulating the condition etc. of anodic oxidation operation and etching procedure, control the shape of pore and repeat pore formation and etch till protuberance comes to a point, also can control the shape (degree of depth etc. of saddle line) of saddle, can control respectively the relief region after copying effective refractive index distribution and recess and protuberance form sharp-pointed shape respectively.

Like this, if use the manufacture method of pressing mold of embodiment of the present invention, the pore shape of more freely antianode oxidized porous aluminium oxide shaping can be carried out.Therefore, can substrate material surface make desired by concaveconvex shape.Therefore, certainly can make the pressing mold of the shape with high antireflective property, and it is also conceivable to design pressing mold because of the change of shape copied with hardening of resin contraction etc. causes.

Further, in the surface treatment of display, anti-dazzle (anti-glare) effect same with anti-reflection effect in most cases also can be tried to achieve.So-called antiglare effect, refers to by the concavo-convex of surface and reflected light is spread, reducing mirroring of light source.The concave-convex surface with this antiglare effect has fully large size compared with the wavelength of light, is at least greater than 780nm, much larger than the size of the fine concaveconvex structure of performance anti-reflection effect.Therefore, the antiglare effect of macroscopical concaveconvex structure and the anti-reflection effect of minute concave-convex structure can be had concurrently.That is, form the concaveconvex structure being greater than 780nm playing antiglare effect at the aluminium of matrix material on the surface, be useful in the method this matrix material making above-mentioned minute concave-convex structure.By adopting the pressing mold made in this way to carry out copying to resin etc., the antireflection material (AGAR) having antiglare effect and anti-reflection effect concurrently can be made.

The manufacture method of the pressing mold of embodiments of the present invention, due to substantially in a wet process technique complete, so also can concaveconvex structure be formed on the surface of the matrix material of various shape.

When concaveconvex structure being copied on film (film), from the viewpoint of cost degradation, being advisable in the roll-to-roll mode adopting throughput rate high, copying of roll generally can be used to use pressing mold.Usually, adopt from pressing mold making pad (shim: thin pressing mold) flat board and the pressing mold be fixed on roller surfaces.Now, due to the pressing mold on flat board is fixed into roll, thus have to produce on convex-concave pattern seam, cannot the problem of large area continuous compound rate.According to such main points, seek to form copying of figure on whole of roller side and use pressing mold.

Figure 19 shows the manufacture method of the above-mentioned pressing mold of application, such as, on the whole outer peripheral face of the matrix material 22a of roll, form the method for concaveconvex structure.

First, outer peripheral face to have the matrix material 22a of the roll of aluminium (cylindric) for anode, be immersed in the electrolytic solution 32 in electrolytic bath 30, the negative electrode 24a of configuration cylindrical shape makes it the outside surrounding anode, applies voltage from power supply 40.As long as matrix material 22a exposes aluminium in most surface, be no matter the aluminium cylinder of discrete material (bulk), or on the surface of the roll matrix material made with other material, form the cylinder of aluminium lamination.In addition, the shape of matrix material 22a is not limited to cylinder, also can be cylinder.Certainly, section shape is also not limited to circle, for ellipse etc. also can.

On the matrix material 22a of this roll, by applying above-mentioned pressing mold method for making, on the whole surface of roller, the fine concaveconvex structure that shape is controlled can be formed in the lump.Thus, can the pressing mold of continuous compound rate when can obtain not forming seam on the figure of concaveconvex structure.

Further, for the object such as periodicity of arrangement improving pore, ideally, the electrolytic solution 32 in anodic oxidation keeps stationary state, but considers the shape etc. of matrix material 22a, also can stir electrolytic solution 32 as required.

Figure 20 shows the manufacture method of the above-mentioned pressing mold of application, such as, on the whole inner peripheral surface of the matrix material 22b of cylindrical shape, form the method for concaveconvex structure.

Now, by by the cylinder be made up of the aluminium of discrete material (bulk) or there is aluminium lamination on inner peripheral surface cylindrical substrate material 22b be used as anode, configure negative electrode 24b in this cylinder 22b inside and carry out anodic oxidation, on the inner peripheral surface of matrix material, making concaveconvex structure with said method.Further, also this inner peripheral surface can be used as pressing mold, but the technology that also can suitably use electroplating method and electroless plating method etc. to know makes the Ni electroforming pressing mold etc. of the shape replicating this inner peripheral surface, and used as pressing mold.

Use above-mentioned pressing mold, antireflection material can be manufactured with the replica method known.Such as, as the method (nanoin-printlithography: printing lithographic method in nanometer) of the structure of making nanometer scale, the replica method that have employed UV sclerosis or heat (circulation) can be enumerated.These methods carry out by die pressing the method that the figure (fine concaveconvex structure) from the pressing mold (ingot mould, mould, former dish) of the fine concaveconvex structure with nano-scale to ray hardening resin or thermoplastic resin copies.

Antireflection material, such as by the replica method that hardens with UV, is carried out following operation (a) ~ (e) successively and is made.

Operation (a): with turning painting machine (such as 3000rpm) by ray hardening resin (such as urethane acrylate (urethaneacrylate) is resin) even application on substrate (such as PET film).

Operation (b): in a vacuum the convex-concave surface of the pressing mold having implemented demoulding process is pressed into ray hardening resin film.

Operation (c): by being open in air, ray hardening resin is filled in the concaveconvex structure of pressing mold.

Operation (d): to the ray hardening resin irradiation ultraviolet radiation (such as, the ultraviolet 10mW of 365nm irradiates 360 seconds) in the concaveconvex structure of pressing mold, ray hardening resin is hardened.

Operation (e): by making pressing mold be separated with substrate, forms the sclerosis nitride layer replicating the ray hardening resin of the concaveconvex structure of pressing mold on a surface of a substrate.

[embodiment]

Referring again to Figure 13, further illustrate the manufacture method of the pressing mold of the embodiment of the present invention.

Matrix material adopts the aluminium sheet 18 (with reference to Figure 13 (a)) surface having been carried out the 10cm × 10cm of planarization.

With the oxalic acid of 0.05mol/L (temperature 3 DEG C, volume 5L, without stirring) as electrolytic solution, carry out anodic oxidation 5 minutes with the DC constant voltage power supply (not changing in time) of 80V, make anodic oxidation porous alumina layer (Figure 13 (b)) from the teeth outwards.

After cleaning with ultrapure water, in the phosphoric acid (30 DEG C) of 8mol/L, dipping 30 minutes, removes this porous alumina layer (Figure 13 (c)).

Then, again after cleaning, alternately repeat to carry out at identical conditions 30 seconds anodised operations (Figure 13 (d)) and dipping carries out the operation (Figure 13 (e)) that etches for 19 minutes 5 times in the phosphoric acid (30 DEG C) of 1mol/L.

Finally, anodic oxidation 30 second (Figure 13 (d)) is carried out under the same conditions.

Figure 21 shows the electron micrograph of the concaveconvex structure of the stamper surface made by the method.Figure 21 (a) represents the front elevation of concaveconvex structure, and (b) represents stereographic map, and (c) represents sectional view.

The adjacent pore interval of concaveconvex structure is about 200nm, although not periodically, pore is by intensive filling.The degree of depth of recess is about 840nm (aspect ratio is about 4.2), and the most deep of recess is in fact a little.Herein, owing to being repeated anodic oxidation operation and etching procedure fully, so as made an explanation with reference to Figure 17, the front end of protuberance also comes to a point, and becomes in fact a little.In addition, the most intensive filling haply that is configured to of recess configures and is formed.

In addition, the side of fine concave portions (pore) has by repeating multistage anodic oxidation operation and etching procedure and the stepped shape formed.

On the surface of concaveconvex structure with obtained pressing mold, by pressing coating UV hardening resin on a pet film, (ザ イ ンクデツ Network company manufactures, urethane acrylate system resin) film carry out UV irradiation (the ultraviolet 10mW of 365nm irradiates 360 seconds), obtain by antireflection material concaveconvex structure being copied to the resin molding on surface and form.

The result of observing the surface of the antireflection material obtained with scanning electron microscope is shown in Figure 22.Figure 22 (a) is about the SEM photo of 63500 times, and (b) is about the SEM photo of 36800 times.As can be seen from Figure 22, the side replicating the protuberance of recess of pressing mold also has step-like shape.The spectral reflectivity characteristic of the normal reflection light of this antireflection material is shown in Figure 23.The normal reflection rate of visible region (380nm ~ 780nm) is about less than 0.5%, does not produce diffraction light.

Like this, according to embodiments of the invention, the antireflection material with superior antireflective property can be obtained.

Industrial utilizability

According to the present invention, the generation that can prevent-1 diffraction light can be obtained, and then prevent the antireflection material of generation of zero degree reflection diffracting light.Antireflection material of the present invention can be widely used in the optical elements such as light guide plate, polarization plate, fender, anti-reflection plate or is equipped with liquid crystal display device, the display device such as electrochromism (electro-chromic) display device, electrophoretic display device, EDD etc. of such optical element.

In addition, according to the present invention, the manufacture method of the manufacture method that the pressing mold being suitable for making the antireflection material with moth ocular structure etc. can be provided and the antireflection material employing pressing mold and antireflection material.

Claims (28)

1. a manufacture method for pressing mold, this is the manufacture method of the pressing mold from the teeth outwards with minute concave-convex structure, it is characterized in that,

Comprise following operation:

A () prepares to comprise from the teeth outwards at least containing the operation of the matrix material of the aluminium lamination of more than aluminium 95 quality %;

B (), by carrying out anodic oxidation partly to above-mentioned aluminium lamination, forms the operation with the porous alumina layer of multiple fine concave portions; And

C () contacts with the etching agent of aluminium oxide by making above-mentioned porous alumina layer, make the operation that above-mentioned multiple fine concave portions of above-mentioned porous alumina layer expand,

By alternately repeatedly carrying out above-mentioned operation (b) and (c), above-mentioned porous alumina layer forms the fine concave portions of multiple conical shaped separately with step-like side,

The fine concave portions that the fine protuberance that above-mentioned multiple fine concave portions comprises more than 3 less than 6 is formed around, be formed at more than around this fine concave portions 3 less than 6 fine protuberance summit between be formed with saddle.

2. the manufacture method of pressing mold as claimed in claim 1, is characterized in that,

In the above-mentioned operation (b) of repeatedly carrying out and (c), last operation is above-mentioned operation (b).

3. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

The most deep of above-mentioned multiple fine concave portions is in fact a little.

4. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Above-mentioned matrix material in the substrate of above-mentioned aluminium lamination also containing metal level or the semiconductor layer with electric conductivity.

5. the manufacture method of pressing mold as claimed in claim 4, is characterized in that,

Above-mentioned metal level is formed by valve metal.

6. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Also comprise following operation: define above-mentioned multiple fine concave portions with above-mentioned step-like side on above-mentioned porous alumina layer after, form high rigidity metal level, make it to cover above-mentioned porous alumina layer.

7. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Also comprise following operation: define above-mentioned multiple fine concave portions with above-mentioned step-like side on above-mentioned porous alumina layer after, carry out surface treatment.

8. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Above-mentioned matrix material is cylindric or cylindric, and above-mentioned surface is the outer peripheral face of above-mentioned matrix material, and above-mentioned outer peripheral face is jointlessly formed above-mentioned multiple fine concave portions.

9. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Cylindrically, and above-mentioned surface is the inner peripheral surface of above-mentioned matrix material to above-mentioned matrix material, and above-mentioned inner peripheral surface is jointlessly formed above-mentioned multiple fine concave portions.

10. the manufacture method of pressing mold as claimed in claim 1 or 2, is characterized in that,

Above-mentioned matrix material, under above-mentioned aluminium lamination, has another concaveconvex structure being greater than 780nm.

The manufacture method of 11. pressing molds as claimed in claim 1 or 2, is characterized in that,

The distance of above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure has between adjacent fine concave portions is in the scope of more than 100nm below 200nm.

The manufacture method of 12. pressing molds as claimed in claim 1 or 2, is characterized in that,

Form above-mentioned fine concave portions, above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure is had or not periodically.

The manufacture method of 13. pressing molds as claimed in claim 1 or 2, is characterized in that,

Also comprise following operation: the duplicate adopting the above-mentioned porous alumina layer being formed and have above-mentioned multiple fine concave portions of step-like side separately or the surface structure replicating above-mentioned porous alumina layer, makes metal stamping and pressing.

The manufacture method of 14. 1 kinds of antireflection material, this uses pressing mold to manufacture the method for antireflection material, and it comprises:

The operation of above-mentioned pressing mold is manufactured by the method described in claim 1 or 2; And

Copy the operation of the minute concave-convex structure on the above-mentioned surface of above-mentioned pressing mold.

15. 1 kinds of pressing molds, this is the pressing mold from the teeth outwards with minute concave-convex structure, and it has:

Matrix material; Be arranged on aluminium lamination on above-mentioned matrix material, that at least contain more than aluminium 95 quality %; And the porous alumina layer be arranged on above-mentioned aluminium lamination,

Above-mentioned porous alumina layer has the fine concave portions of multiple conical shaped separately with step-like side,

The fine concave portions that the fine protuberance that above-mentioned multiple fine concave portions comprises more than 3 less than 6 is formed around, be formed at more than around this fine concave portions 3 less than 6 fine protuberance summit between be formed with saddle.

16. pressing molds as claimed in claim 15, is characterized in that,

The most deep of above-mentioned multiple fine concave portions is in fact a little.

17. pressing molds as described in claim 15 or 16, is characterized in that,

Above-mentioned matrix material in the substrate of above-mentioned aluminium lamination also containing metal level or the semiconductor layer with electric conductivity.

18. pressing molds as claimed in claim 17, is characterized in that,

Above-mentioned metal level is formed by valve metal.

19. pressing molds as described in claim 15 or 16, is characterized in that,

Also there is the high rigidity metal level covering above-mentioned porous alumina layer.

20. pressing molds as described in claim 15 or 16, is characterized in that,

Surface treatment is implemented to above-mentioned minute concave-convex structure.

21. pressing molds as described in claim 15 or 16, is characterized in that,

Above-mentioned matrix material is cylindric or cylindric, and above-mentioned surface is the outer peripheral face of above-mentioned matrix material, and above-mentioned outer peripheral face is jointlessly formed above-mentioned multiple fine concave portions.

22. pressing molds as described in claim 15 or 16, is characterized in that,

Cylindrically, and above-mentioned surface is the inner peripheral surface of above-mentioned matrix material to above-mentioned matrix material, and above-mentioned inner peripheral surface is jointlessly formed above-mentioned multiple fine concave portions.

23. pressing molds as described in claim 15 or 16, is characterized in that,

Above-mentioned matrix material, under above-mentioned aluminium lamination, has another concaveconvex structure being greater than 780nm.

24. pressing molds as described in claim 15 or 16, is characterized in that,

The distance of above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure has between adjacent fine concave portions is in the scope of more than 100nm below 200nm.

25. pressing molds as described in claim 15 or 16, is characterized in that,

Be configured to above-mentioned multiple fine concave portions that above-mentioned minute concave-convex structure has or not periodically.

26. 1 kinds of antireflection material, this is the antireflection material from the teeth outwards with minute concave-convex structure,

Above-mentioned minute concave-convex structure comprises the protuberance of the multiple fine conical shaped separately with step-like side,

The fine protuberance that the fine concave portions that above-mentioned multiple fine protuberance comprises more than 3 less than 6 is formed around, in the structure making above-mentioned minute concave-convex structure reverse, the fine concave portions that the fine protuberance that multiple fine concave portions comprises more than 3 less than 6 is formed around, be formed at more than around this fine concave portions 3 less than 6 fine protuberance summit between be formed with saddle.

27. antireflection material as claimed in claim 26, is characterized in that,

Distance between the arbitrary protuberance adjoined each other among the above-mentioned multiple fine protuberance of supposition is P, the minimal wave length of incident light is λ _min, above-mentioned incident light maximum incident angle be θ i _max, incident medium refractive index be ni, the refractive index of above-mentioned antireflection material is when being ns, meets following formula (1 ')

[mathematical expression 1 ']

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\mathrm{ni}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}...\left(1^{,}\right).$

28. antireflection material as claimed in claim 27, it is characterized in that, above-mentioned formula (1 ') also meets following formula (2 ')

[mathematical expression 2 ']

$\frac{P}{{\mathrm{\&lambda;}}_{\min }}<\frac{1}{\max \{\mathrm{ni},\mathrm{ns}\}+\mathrm{ni}\&CenterDot;\sin \mathrm{\&theta;}{i}_{\max }}...\left(2^{,}\right)$

In formula, max{ni, ns} mean the large side of refractive index among ni and ns.