JP2006130841A - Method for producing member having reflection preventing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a member having a high precision reflection preventing structure even when the surface has a large area and is shaped in a curved surface. <P>SOLUTION: A core having a catalytic function is formed on the surface of an original board material. Next, needle crystals are formed on the surface of the original board material by growing crystals on the core. Next, a mold is formed by using the original board material with the needle crystals formed. When the mold is an electroformed mold, a molding resin raw material is molded by injection molding, press molding, a nano-imprinting method, or the like by using the electroformed mold. An original board material mainly containing quartz glass is used as the original board material, and the surface of the original board material is subjected to dry etching with the needle crystals used as a mask. Next, when the mold is formed by forming a protective mold releasing film, a molding raw material of multi-component glass is press-molded by using the obtained mold. In this way, the member having the reflection preventing structure good in surface precision which comprises a resin having a large area and the shape of a curved surface and the multi-component glass. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method of manufacturing a member including an antireflection structure, and more specifically, includes an antireflection structure that can form an antireflection structure with high accuracy even on a large-area and curved surface. The present invention relates to a method for manufacturing a member.

  Optical elements such as lenses and optical components such as camera barrels that have been subjected to antireflection treatment for incident light are used in various applications. The optical functional surfaces of these optical elements and optical components are generally subjected to antireflection treatment by techniques such as vapor deposition, sputtering, and coating, and are provided with a single layer film or a low refractive index layer comprising a low refractive index layer. And an antireflective film such as a multilayer film in which a high refractive index layer is laminated (for example, Patent Document 1).

  Such an antireflection film has been widely used because it can be formed by a general method such as vapor deposition or sputtering, but a complicated process is required to control the optical film thickness of the antireflection film with high accuracy. Therefore, improvement in productivity and cost has been desired. In addition, since such an antireflection film has wavelength dependency, the antireflection effect at a wavelength other than a predetermined wavelength is reduced, and good antireflection is achieved over the entire visible light region required in the imaging optical apparatus. In addition, since there is an angle dependency problem that the antireflection effect decreases as the incident angle increases, an antireflection method with improved wavelength dependency and angle dependency is desired. It was.

  Therefore, as a method for solving these problems, in recent years, a technology for forming a structure called an antireflection structure on which the surface of an optical element or optical component is arranged in a very fine conical uneven shape is arranged in an array. Has attracted attention. More specifically, the antireflection structure is a structure in which conical uneven shapes are arranged in an array at a pitch equal to or smaller than the wavelength of incident light (for example, submicron pitch in the case of visible light). The aspect ratio, which is the ratio of the pitch and height of the concavo-convex shape, is 1 or more.

  When such an antireflection structure is formed on the surface of an optical element or optical component, the refractive index distribution on the surface changes very smoothly, and incident light having a wavelength longer than the arrangement pitch of the conical concavo-convex shape is not received. , Almost all enter the inside of the optical element or optical component. Therefore, reflection of light from the surface of the optical element or optical component can be prevented. Moreover, even if the incident angle of incident light increases, the antireflection effect does not decrease so much. Thus, if the antireflection structure can be formed on the surface of the optical element or optical component, the wavelength dependency and the incident angle dependency, which are problems in the antireflection film, can be solved.

As a method of forming the antireflection structure, for example, there is one described in Patent Document 2. In this method, first, a resist pattern is formed by patterning on the material surface of an optical element made of quartz glass or the like by an electron beam (EB) drawing method, and on the surface of the optical element material based on the resist pattern. A chromium (Cr) mask having a submicron pitch structure is directly formed. Then, the portion other than that covered with the mask of the optical element material is finely processed by dry etching.
JP 2001-127852 A JP 2001-272505 A

  However, in the microfabrication method using the dry etching process as in the method described in Patent Document 2, depending on the optical material used, the surface may be very rough after the etching process or the etching rate may be very slow. There is a problem that optical materials that can be used are limited. That is, there is no particular problem as long as it is a single component material such as quartz glass, but for example, the above-described method is applied to multi-component glass and resin materials used in imaging optical devices designed with various optical constants. Then, a desired selection ratio cannot be obtained, and an optical element or an optical component including an antireflection structure having a large aspect ratio cannot be obtained.

  In addition, as in Patent Document 2, the EB drawing method is generally used to form a very fine pattern with a submicron pitch. However, if the EB drawing method is used for patterning the submicron pattern, a very long drawing time is required. Depending on the pattern shape and conditions to be drawn, for example, it takes about 5 hours to draw a circular pattern (diameter 0.2 μm) at a pitch of 0.25 μm in a 5 mm square region. Therefore, for example, drawing on an area (50 mm square) corresponding to the entire inner surface of the camera barrel requires 500 hours of drawing time, and mass production is performed by directly forming an antireflection structure on the optical material. Is practically impossible and it is also quite difficult to manufacture molds.

  Furthermore, in the method using the EB drawing method, it is very difficult to draw a fine pattern on a curved surface such as a lens, and an electron beam drawing apparatus provided with a stage capable of very special three-dimensional position control. Is required. Therefore, in reality, it is impossible to form an antireflection structure on the lens surface using electron beam drawing.

  Therefore, an object of the present invention is to provide a method for manufacturing a member provided with an antireflection structure that can form an antireflection structure with high accuracy even on a large-area and curved surface.

  This invention which solves the said subject is a manufacturing method of the member provided with the reflection preventing structure which consists of the following processes. That is, first, nucleation having a catalytic function is performed on the surface of the master material. Next, acicular crystals are formed on the surface of the master material by growing crystals on the nuclei. Next, a mold is formed using a master material on which needle-like crystals are formed. Then, a member provided with the antireflection structure is formed using the obtained mold. Thus, by forming a needle crystal on the core formed on the surface of the master material, a highly accurate antireflection structure can be formed even on a large area and curved surface. A mold having such an antireflection structure can be manufactured at low cost. Since such a mold can be easily manufactured, an antireflection structure can be easily formed on various members.

  The member in the present invention is specifically an optical element or an optical component. As described above, even if the surface has a large area and a curved surface, a mold having a high-precision anti-reflection structure can be easily manufactured. Therefore, an anti-reflection structure can be easily applied to either an optical element or an optical component. The body can be formed.

  When forming acicular crystals on the surface of the master material, any one of chemical vapor deposition, vapor phase epitaxy, molecular beam epitaxy, and electroless plating may be used. A crystal containing at least one selected from silicon nitride, silicon dioxide, boron nitride, and metal is grown.

  Further, when an electroforming mold is formed when forming a mold, a molding material made of a resin material is molded using the electroforming mold when forming a member. The molding process here is performed by any one of injection molding, press molding, and nanoimprinting. Further, when forming the electroforming mold, the water repellent treatment may be applied to the molding surface of the electroforming mold.

Further, in the present invention, when forming the mold, if it is obtained by performing a dry etching process on the surface of the master material using the acicular crystal as a mask and then forming a protective release film, A molding material made of multi-component glass is press-molded using the obtained mold. The master material at this time is preferably a material with less surface roughness caused by dry etching. Specifically, a silicon oxide (SiO ₂ ) film or silicon (on silica glass, silicon, nickel (Ni) alloy, and cemented carbide) It is desirable that it is one selected from the group consisting of Si) films.

  The protective release film is preferably formed of at least one metal selected from the group consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, rhenium, tungsten and tantalum.

  When forming a press mold, a carbon film or boron nitride film may be formed on the surface of the mold after the protective release film is formed. Then, when the molding material made of multi-component glass is press-molded, it is released without cooling. By such treatment, even if multi-component glass is used as an optical element or optical component, it can be easily released without impairing the shape of the formed antireflection structure. The same effect can be obtained by forming the carbon film or boron nitride film on the surface of the molding material made of multi-component glass.

  The acicular crystals in the present invention are formed in an array at a pitch equal to or less than the wavelength of light that should be prevented from being reflected in the member, and the aspect ratio is 1 or more.

  As described above, according to the present invention, a mold for forming a member having an antireflection structure is formed. A nucleus having a catalytic function is formed on the surface of a master material, and a needle-like crystal is formed on the nucleus. By forming the film, it is possible to easily form an antireflection structure having a very small wavelength dependency and incident angle dependency even on a large area or a curved surface. Then, by molding an optical material using the obtained mold, it is possible to very easily form a highly accurate antireflection structure on various members made of various optical materials, that is, optical elements and optical components. .

(First embodiment)
Below, the manufacturing method of the member provided with the reflection preventing structure which concerns on the 1st Embodiment of this invention is demonstrated. In this embodiment, first, an electroforming mold is formed by forming a needle-like crystal on the surface of a master material, and a member provided with an antireflection structure is formed using this electroforming mold. Specifically, the members in the present embodiment include optical elements such as lenses, prisms, filters, optical sheets, and diffraction gratings, and mechanical parts for holding optical elements such as lens barrels. In the following description, an optical sheet will be described as an example.

  FIG. 1 is a cross-sectional view of a substrate and a mold at each stage in the process of manufacturing an electroforming mold according to the present embodiment. FIG. 1 (a) shows a master material used to form an electroforming mold. As the master material, a single crystal silicon wafer substrate 11 having a diameter of 100 mm oriented in the (100) plane is used, and the surface thereof is smoothly polished to a surface roughness Ra of about 2 nm. Nuclei having a catalytic function are formed on the surface of the single crystal silicon wafer substrate 11. Here, the nucleus having a catalytic function is a substance that adsorbs a reactive gas on the surface of the nucleus and causes a redox reaction or the like on the surface of the nucleus. For example, a metal element having d electrons is deposited. The small nuclei formed initially on the substrate surface by the method or the sputtering method can be mentioned.

  FIG. 1B shows a state in which island islands 12 of Cr are formed on the surface of the single crystal silicon wafer substrate 11 as nuclei having a catalytic function. In order to obtain the substrate in the state shown in FIG. 1B, first, Cr is deposited on the surface of the single crystal silicon wafer substrate 11 by electron beam vacuum deposition using Cr metal as a raw material. Then, the deposition is stopped when the Cr island-like crystal 12 is formed. The obtained island crystals 12 were oriented in the (100) plane, and were formed almost uniformly and densely on the surface of the single crystal silicon wafer substrate 11 at a pitch of 250 nm.

  FIG. 1C shows a state in which the needle-like crystal 13 is formed on the island-like crystal 12. In order to obtain a substrate in such a state, first, the single crystal silicon wafer substrate 11 on which the island-like crystals 12 are formed is exposed to a TEOS (tetraethoxysilane) gas atmosphere, the substrate temperature is 200 ° C., the gas pressure is A discharge plasma is generated by applying a high frequency of 13.56 MHz under the condition of 50 Pa. Then, a crystal of silicon (Si) is grown on the island-like crystal 12 by a CVD (chemical vapor deposition) method to form a needle-like crystal 13. Crystal growth stops when the size of the acicular crystal 13 reaches a diameter of 250 nm and a height of 800 nm. In addition, the needle-like crystal 13 in the present invention has a pitch equal to or less than a wavelength of light (hereinafter referred to as a use wavelength) that should be prevented from being reflected when using a member on which an antireflection structure is formed, here, an optical sheet. It is formed in an array shape so that the aspect ratio is 1 or more.

FIG. 1 (d) shows a state in which the electroforming mold 14 that is duplicated from the single crystal silicon wafer substrate 11 on which the needle-like crystal 13 is formed is formed. In order to obtain a substrate in such a state, first, the surface of the single crystal silicon wafer substrate 11 on which the needle-like crystals 13 are formed is activated with palladium (Pd). Next, this substrate is immersed in an electroless nickel (Ni) -phosphorus (P) plating solution to form an electroless Ni—P plating layer having a thickness of 10 nm on the surface of the needle-like crystal 13. Give. Next, using an electroless Ni—P plating layer as a cathode electrode and a platinum (Pt) plate as a counter electrode, in a sulfamic acid Ni plating solution, under a current density of 0.5 A / dm ^{2 to} 5 A / dm ² . The electroforming 14 is obtained by performing electroplating until the thickness of the plated portion becomes about 2 mm.

  FIG. 1E is a cross-sectional view showing the configuration of the electroforming mold 14 provided with the antireflection structure 15. The electroforming mold 14 is obtained by separating the single-crystal silicon wafer substrate 11 on which the needle-like crystals 13 are formed and the electroforming mold 14 from the substrate in the state shown in FIG. On the molding surface of the obtained electroforming mold 14, an antireflection structure 15 is formed in which the inverted shape of the needle crystal 13 having a diameter of 250 nm and a height of 800 nm is formed almost uniformly and densely at a pitch of 250 nm. The

  In the electroforming mold 14 manufactured as described above, a nucleus having a catalytic function is formed in advance on a master material (single crystal silicon wafer substrate 11), and a needle crystal 13 is grown on the nucleus. Therefore, it is possible to easily manufacture an antireflection structure having very small wavelength dependency and incident angle dependency. The electroforming mold 14 provided with such an antireflection structure can be used as a mold for directly injection-molding or press-molding heat-softened resin, low melting point glass, or the like. Below, the process of forming an antireflection structure on an optical sheet using the electroforming mold 14 manufactured as described above will be described.

  FIG. 2 is a cross-sectional view of the device at each stage in the process of manufacturing an optical sheet including the antireflection structure according to the present embodiment. Here, a polyolefin resin is used as a molding material for forming the optical sheet, and the optical sheet is formed by press molding. Fig.2 (a) is sectional drawing which shows the structure of the molding machine used for manufacture of an optical sheet. The molding machine includes a lower die 21, an upper die 23, a preheating stage 24, a press stage 25, a cooling stage 26, an upper head 27, a cylinder 28, a die inlet 29, and a die outlet 210.

  In FIG. 2A, the electroforming mold 14 formed in the above process is fixed as an upper mold 23 to an upper head 27 that is configured to be movable in a vertical direction (arrow direction in the figure) by a cylinder 28. A press stage 25 is disposed at a position facing the upper mold 23, and both the upper mold 23 and the press stage 25 are heated to a predetermined temperature (here, 180 ° C.). The lower mold 21 that forms a pair with the upper mold 23 is a flat quartz glass (diameter 100 mm, thickness 2 mm) whose surface is polished to a mirror surface, and mounts a polyolefin resin having a diameter 80 mm and a thickness 1 mm, which is a molding material 22. In the state where it is placed, it is supplied from the mold inlet 29 to the preheating stage 24. The preheating stage 24 is heated to 180 ° C. The lower mold 21 supplied to the preheating stage 24 is sequentially conveyed to the press stage 25 and the cooling stage 26.

  FIG. 2B shows a state in which the molding material 22 supplied to the press stage 25 is subjected to press molding. As the cylinder 28 descends, the upper mold 23 descends, and the molding material 22 is press-molded by the upper mold 23 and the lower mold 21. Here, the molding material 22 is pressed for 1 minute at a pressure of 5,000 N on the press stage 25 set to 180 ° C. by the upper mold 23 and the lower mold 21 which are also set to 180 ° C. Next, while maintaining the pressure as it is, when the temperature of the press stage, the upper mold 23 and the lower mold 21 is lowered to 100 ° C., the upper mold 23 is raised together with the upper head 27 by raising the cylinder 28. Then, the upper mold 23 is released from the molding material 22. As a result, the antireflection structure 15 formed on the upper mold 23 is transferred to the surface of the molding material 22, and an optical sheet 211 having a diameter of 90 mm on which the antireflection structure 20 is formed is obtained. When the upper mold 23 is released, the lower mold 21 is provided with the antireflection structure 20 because the outer peripheral portion is pressed against the press stage 25 so as to be fixed to the press stage 25 (not shown). The optical sheet 211 remains on the lower mold 21. In this state, the lower mold 21 on which the optical sheet 211 is placed is conveyed to the cooling stage 26 that is water-cooled.

  FIG. 2C shows a state where the lower mold 21 on which the optical sheet 211 is placed is conveyed to the cooling stage 26. The optical sheet 211 that has been transported and cooled to the cooling stage 26 is carried out of the molding die 210 to the outside of the molding machine together with the lower die 21. And the shaping | molding process of the optical sheet 211 provided with the reflection preventing structure 20 is completed by removing the optical sheet 211 cooled from the lower mold | type 21. FIG. The obtained optical sheet 211 had a diameter of 90 mm and a thickness of 0.7 mm. When the surface reflectance was measured, the wavelength was 600 nm and the reflectance was 0.1%.

  As described above, the time required to form the optical sheet 211 provided with the antireflection structure 20 using the electroforming mold 14 provided with the antireflection structure 15 is about several minutes. Further, the total processing time is about several hours for the time required for manufacturing the electroforming mold 14 itself. On the other hand, when an antireflection structure is formed by a conventional EB drawing method, it is only necessary to form an antireflection structure on the surface of a polyolefin resin sheet of the same size (diameter 90 mm). It takes more time to draw. Therefore, it can be said that the productivity of the manufacturing method of the present invention has been dramatically improved.

  The electroforming mold 14 described above may be further provided with a step of performing a water repellent treatment on the molding surface of the electroforming mold 14 after the step of FIG. A conventionally known material can be used as the water repellent agent used for the water repellent treatment, and when the electroforming mold 14 is used as a mold by coating the water repellent treatment material on the molding surface of the electroforming mold 14. Furthermore, adhesion of the molding material 22, particularly the resin material, can be prevented. Therefore, if the molding surface of the electroforming mold 14 is subjected to water repellent treatment, the electroforming mold 14 (upper mold 23) can be easily obtained without lowering the temperature of the molding die or the like to 100 ° C. in the step of FIG. ) Can be released, and the molding cycle is further shortened.

In the above description, an example in which the Si needle crystal 13 is formed on the surface of the master material by the CVD method has been described. However, the present invention is not limited to this, and a vapor phase is substituted for the CVD method. Any one of an epitaxy (VPE) method, a molecular beam epitaxy (MBE) method, and an electroless plating method can be applied. Further, not only the Si needle crystal 13 but also a crystal containing one or more of carbon (C), silicon nitride (SiC), silicon dioxide (SiO ₂ ), boron nitride (BN), and metal is grown. It can also be made into acicular crystals.

  Further, in the above description, the example in which the member provided with the antireflection structure is formed by the press molding method using the electroforming mold 14 as an upper mold has been described, but the present invention is not limited thereto, The electroforming mold 14 can be used for a lower mold or both an upper mold and a lower mold. Moreover, when molding a member provided with an antireflection structure, it can be applied not only to a press molding method but also to an injection molding method, a nanoimprint method, and the like.

(Embodiment 2)
Below, the manufacturing method of the member provided with the reflection preventing structure which concerns on the 2nd Embodiment of this invention is demonstrated. In the present embodiment, a method for manufacturing a double-sided convex lens having an antireflection structure will be described. This embodiment is different from the first embodiment in that a master disk material mainly composed of quartz glass is used as a master material, and a double-sided convex lens made of multicomponent glass is formed as a member having an antireflection structure. However, the process of forming the needle crystal on the master material and the basic configuration of the molding machine that performs press molding are substantially the same as those in the first embodiment.

  FIG. 3 is a cross-sectional view of the master material at each stage in the process of manufacturing a convex lens molding die provided with the antireflection structure according to this embodiment. Here, a process of manufacturing a mold for manufacturing a double-sided convex lens made of multicomponent glass provided with a conical antireflection structure having a pitch of 250 nm and a depth of 800 nm will be described. FIG. 3A shows the state of the master material of the convex lens molding die. In the present embodiment, such a master material uses a cylindrical quartz glass substrate 31 having a thickness of 2 mm and a diameter of 5 mm, and performs high-precision grinding and polishing on the surface (press surface) of the quartz glass substrate 31. A molding surface 31a having a concave curved surface, which is an inverted shape of a convex lens, is formed on the surface obtained by applying and polishing.

  FIG. 3B shows a state in which Pd island-like crystals 32 are formed on the molding surface 31 a of the quartz glass substrate 31 as nuclei having a catalytic function. In order to obtain the island-shaped crystal 32 shown in FIG. 3B, first, Pd is sputtered on the molding surface 31a of the quartz glass substrate 31 processed into a concave curved surface by a sputtering method using argon (Ar) gas. To do. Then, the sputtering is stopped when the Pd island crystal 32 is formed. At this time, the pressure of Ar gas is 0.5 Pa, and the supplied high frequency (RF) power is 300 W.

  FIG. 3C shows a state in which the needle crystal 33 is formed on the island crystal 32. In order to obtain a substrate in such a state, first, Ni—Cu—P needle crystals 33 are grown on Pd island crystals 32 by electroless plating, and Ni—Cu—P needles are obtained. Crystal growth is stopped when the size of the crystal 33 reaches a diameter of 250 nm and a height of 200 nm. As a result, a needle-like crystal 33 made of Ni—Cu—P and having a diameter of 250 nm and a height of 200 nm is formed on the molding surface 31a of the quartz glass substrate 31 as a mask corresponding to the antireflection structure. The mask of the Ni—Cu—P needle-like crystals 33 is densely formed in an array at a pitch equal to or shorter than the wavelength used.

FIG. 3D shows a state where the molding surface 31a of the quartz glass substrate 31 is dry-etched using the needle-like crystal 33 as a mask. In order to obtain a substrate in such a state, a quartz glass substrate 31 on which a mask of Ni—Cu—P needle crystals 33 is formed is placed in an RF dry etching apparatus, and CHF ₃ gas, O ₂ gas, Is used to etch the surface of the quartz glass substrate 31 until the mask of the Ni—Cu—P needle crystals 33 disappears. Thereby, the convex lens molding die 34 in which the conical antireflection structure 30 having a pitch of 250 nm and a height of 800 nm is formed on the molding surface 31 a of the quartz glass substrate 31 is obtained. From this result, it is understood that the etching selectivity between the mask of the Ni—Cu—P needle crystal 33 and the quartz glass is 4 in this embodiment.

  Finally, a sputtering method was used to form a Pt—Ir—W alloy film (not shown) with a thickness of 0.05 μm as a release protection film for surface protection via a Cr film. Thus, a convex lens molding die 34 having an antireflection structure was obtained. In the obtained convex lens molding die 34, the antireflection structure 30 having a fine shape on the curved molding surface was uniformly formed.

  Hereinafter, a method for producing a biconvex lens made of multi-component glass having an antireflection structure using the convex lens molding die 34 produced as described above will be described. FIG. 4 is a cross-sectional view showing a configuration of a molding machine used for manufacturing a biconvex lens. The basic configuration of the molding machine is almost the same as the molding machine shown in FIG. 2 described in the first embodiment.

In the molding machine shown in FIG. 4 (a), two convex lens molding dies 34 having antireflection structures are prepared, and one of them is provided with a C sputtered film in order to further improve mold release properties. It is formed with a thickness of 05 μm. The convex lens molding die 34 on which the C sputtered film was formed was fixed to the upper head 47 as the upper die 43, and the convex lens molding die 34 on which the sputtered film was not formed was placed on the preheating stage 44 as the lower die 41. Then, in order to prevent the oxidation of the mold, N ₂ gas is introduced into the molding machine from the gas inlet 412 at a flow rate of 30 liters / minute, and the press stage 45 is heated to a predetermined temperature (here, 580 ° C.). At the same time, the preheating stage 44 was also heated to 580 ° C. As the molding material 42, a marble crown-type borosilicate glass (glass transition point (Tg): 501 ° C., yield point (At): 549 ° C.) having a diameter of 4.3 mm and a thickness of 2 mm is used. In the state of being placed on top, it was introduced into the molding machine through the mold inlet 49 and heated on the preheating stage 44 set at 580 ° C. for 3 minutes.

  FIG. 4B shows a state in which the forming material 42 supplied to the press stage 45 is subjected to press working. The press stage 45 is set to 580 ° C., and the upper die 43 is lowered when the cylinder 48 is lowered, and the molding material 42 is press-molded by the upper die 43 and the lower die 41. The pressing conditions are 2 minutes at a pressure of 1000 N. Then, without lowering the temperature as it is, the cylinder 48 is raised, the upper die 43 is raised together with the upper head 47, and the upper die 43 is released from the molding material 42. As a result, the antireflection structure 30 formed on the upper mold 43 and the lower mold 41 is transferred to the surface of the molding material 42, and a biconvex lens having the antireflection structure 30 formed on the surface is formed as the optical element 411. can get. When the upper mold 43 is released, the lower mold 41 is pressed against the press stage 45 so that the lower mold 41 is fixed to the press stage 45 (not shown). The provided optical element 411 is put on the lower mold 41, and in that state, it is transported to the cooling stage 46 set to 300 ° C. and cooled for 3 minutes.

  FIG. 4C shows a state in which the lower mold 41 on which the optical element 411 having the antireflection structure is placed is conveyed to the cooling stage 46. The optical element 411 conveyed to the cooling stage 46 is carried out of the molding machine through the mold take-out port 410 together with the lower mold 41. And by removing from the lower mold | type 41, manufacture of the optical element 411 provided with the reflection preventing structure is completed. The obtained optical element 411 was a biconvex lens having a diameter of 4.5 mm and a thickness of 1.3 mm. When the surface reflectance was measured, the wavelength was 600 nm and the reflectance was 0.05%.

  As described above, according to the method for manufacturing the member provided with the antireflection structure according to the present embodiment, even if multi-component glass is used as the molding material 42, as described in the process of FIG. Even without lowering the temperature, that is, without cooling the molding material 42, the mold can be easily released without impairing the shape of the antireflection structure. Further, the antireflection structure can be easily formed on a curved surface such as a biconvex lens. Therefore, it can be applied to optical elements and optical components for various uses.

  In the above description, the example in which the C film is formed on the surface of the molding die has been described. However, a boron nitride film can be applied in addition to the C film, and the molding material 42 can be used instead of the molding die. Even if these films are formed on the surface, the same effect can be obtained. In the above description, a cylindrical master material is used to form the convex lens mold in the above description, but the shape is not particularly limited, and depends on the shape of the optical element and optical component to be manufactured. Can be selected as appropriate.

  In the above description, the example in which the Pt—Ir—W alloy film is formed as the protective release film has been described. However, the present invention is not limited to this, and platinum, palladium, iridium, rhodium, A material formed of at least one metal selected from the group consisting of osmium, ruthenium, rhenium, tungsten and tantalum is applicable.

Furthermore, in the above description, Ni-Cu-P needle-like crystals by electroless plating were used to form the shape of the antireflection structure, but after performing nucleation with a catalytic function on the surface of the master material, By growing a crystal containing one or more of C, Si, SiC, SiO ₂ , BN, and metal on the core by CVD, VPE, or MBE, the acicular crystal is formed on the surface of the master material. Can be formed.

  Since the present invention has a feature that a highly accurate antireflection structure can be formed even on a large surface and a curved surface, such as a lens element, a prism element, and a mirror element that require an antireflection effect. Widely applicable to optical components such as optical elements and lens barrels, etc., optical pickup optical systems of optical reproduction recording devices in which these optical elements and optical components are used, photographing optical systems such as digital still cameras, projectors Suitable for projection systems, illumination systems, optical scanning optical systems, and the like.

The figure explaining the manufacturing method of the electroforming mold provided with the anti-reflective structure concerning the 1st Embodiment of this invention The figure explaining the manufacturing method of the optical sheet provided with the reflection preventing structure concerning the embodiment The figure explaining the manufacturing method of the convex lens shaping | molding die provided with the reflection preventing structure which concerns on the 2nd Embodiment of this invention. The figure explaining the shaping | molding method of the biconvex lens provided with the reflection preventing structure which concerns on the same embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Single-crystal silicon wafer substrate 12 Island-like crystal 13 Needle-like crystal 14 Electromold 15 Antireflection structure 20 Antireflection structure 21, 41 Lower mold 22, 42 Molding material 23, 43 Upper mold 24, 44 Preheating stage 25, 45 Press stage 26, 46 Cooling stage 27, 47 Upper head 28, 48 Cylinder 29, 49 Type inlet 210, 410 Type outlet 211, 411 Optical element 31 Quartz glass substrate 32 Island crystal 33 Needle crystal 34 For convex lens molding Type 412 Gas inlet

Claims (12)

Nucleation process with catalytic function on the surface of the master material;
Forming acicular crystals on the surface of the master material by growing crystals on the nuclei;
Forming a mold using a master material on which the needle-like crystals are formed;
Forming a member provided with the antireflection structure using the mold, and a method for producing the member provided with the antireflection structure.   The method for producing a member having an antireflection structure according to claim 1, wherein the member is an optical element or an optical component.   The step of forming the acicular crystal on the surface of the master material is performed by any one of chemical vapor deposition, vapor phase epitaxy, molecular beam epitaxy, and electroless plating, and on the nucleus, The member having an antireflection structure according to claim 1, wherein a crystal containing at least one selected from carbon, silicon, silicon nitride, silicon dioxide, boron nitride, and metal is grown. Production method. In the step of forming the mold, an electroforming mold is formed,
The method for producing a member having an antireflection structure according to claim 1, wherein in the step of forming the member, a molding material made of a resin material is molded using the electroforming mold.   The method for producing a member having an antireflection structure according to claim 4, wherein the step of performing the molding process is performed by any one of an injection molding method, a press molding method, and a nanoimprint method.   The method of manufacturing a member having an antireflection structure according to claim 4, wherein the step of forming the electroforming mold further includes a step of performing a water repellent treatment on a molding surface of the electroforming mold. The step of forming the mold includes a step of performing a dry etching process on the surface of the master material using the acicular crystal as a mask, and a step of forming a protective release film,
The method for producing a member having an antireflection structure according to claim 1, wherein the step of forming the member comprises press-molding a molding material made of multi-component glass using the mold.   The master material is a material with less surface roughness caused by dry etching, and is one selected from the group consisting of quartz glass, silicon, nickel alloy, and cemented carbide formed with a silicon oxide film or a silicon film. The manufacturing method of the member provided with the reflection preventing structure of Claim 7 characterized by the above-mentioned.   The protective release film is formed of at least one metal selected from the group consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, rhenium, tungsten and tantalum. The manufacturing method of the member provided with the reflection preventing structure of description. The step of forming the press molding die further includes the step of forming a carbon film or a boron nitride film on the surface of the die after forming the protective release film,
The method for producing a member having an antireflection structure according to claim 7, wherein the molding material made of multicomponent glass is press-molded without being cooled. Prior to the press molding, further comprising a step of forming a carbon film or a boron nitride film on the surface of the molding material made of the multicomponent glass,
The method for producing a member having an antireflection structure according to claim 7, wherein the molding material made of multicomponent glass is press-molded without being cooled. 2. The antireflection structure according to claim 1, wherein the acicular crystals are formed in an array at a pitch equal to or less than a wavelength of light to be prevented from being reflected in the member, and an aspect ratio is 1 or more. The manufacturing method of the member provided with.

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