JP2000284136A - Production of two-dimensional and three-dimensional photonic crystals - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method of easily producing two-dimensional and three- dimensional photonic crystals while facilitating the introduction of inhomogenenous parts. SOLUTION: This method of producing of the two-dimensional photonic crystal has a process for producing hyperfine structures in two-dimensional cyclic arrangement on a substrate 11, a process for forming a thin film of a material 12 with a refractive index n1 on the hyperfine structures, and a process for intruding the thin film into the hyperfine structure. By the method of producing the three-dimensional photonic crystal, a laminate body structure is formed by repating at least once the process for forming a 1st thin film of a 1st material with the refractive index n1, the process for processing a mold having specific hyperfine structures against the 1st thin film for imprinting, the process for laminating a 2nd thin film made of a 2nd material with the refractive index n2 on the 1st thin film, and the process for pressing the mold with specific hyperfine structures against the 2nd thin film for imprinting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing two-dimensional and three-dimensional photonic crystals applicable as optical devices such as optical waveguides and resonators.

[0002]

2. Description of the Related Art A photonic crystal is a periodic structure in which substances having different refractive indexes are periodically arranged. When the refractive index between the substances increases, light called a photonic band cap is formed based on multiple reflection. A frequency band that prohibits propagation appears. Therefore, if an inhomogeneous portion that disturbs the period is introduced into the periodic structure, light is confined in that portion, so that a photonic crystal can be applied as an optical waveguide or a resonator. Therefore, by introducing an inhomogeneous portion into a photonic crystal having a three-dimensional periodic structure (hereinafter also referred to as a three-dimensional photonic crystal), a higher light confinement effect can be achieved. High-performance optical devices such as three-dimensional optical circuits and ultra-low threshold lasers are expected to be realized.

As a conventional method for producing a three-dimensional photonic crystal, the following has been reported.

(1) A method using dry etching (CC Cheng et al., J. Vac. Sci. Technol., B. vol.
13, no. 6, pp. 2696-2700, 1995) In this method, holes are formed by dry etching on a substrate having a high refractive index such as gallium arsenide. At this time, holes are formed in three directions at 120 degrees at an inclination of about 35 degrees from an axis perpendicular to the surface of the substrate. This method theoretically shows that a periodic structure close to a diamond structure is obtained and a photonic band gap is formed in all directions.

(2) A method utilizing X-ray lithography (G. Feiertag, et al., Appl. Phys. Lett., Vol. 71,
no. 11, pp. 1441-1443) This method is a method of obtaining a diamond structure by applying X-ray lithography, similarly to the method (1). X-rays are applied to the curable photosensitive resin from the same direction as in the method (1) to cure the resin, and a photonic crystal is produced by development, leaving a portion corresponding to the hole in the method (1). is there.

(3) Method using self-arrangement of microspheres (H. Miguez, et al., Appl. Phys. Lett. Vol. 71, n
o. 9, pp. 1148-1150, 1997) This method forms photonic crystals by regularly growing and arranging fine particles of silicon dioxide having a uniform diameter in a three-dimensional direction from a colloidal dispersion.

(4) Method using bonding (S.N.
oda et al., Jpn. J. Appl. Phys., vol. 35, pp. L909-
912, 1996) In this method, a two-dimensional periodic structure is fabricated by lithography and dry etching on a high refractive index thin film formed on a substrate, and then the substrates are reverse-fused (fusion of the periodic structures).
-A three-dimensional photonic crystal is formed by repeatedly removing unnecessary portions of the substrate and stacking a two-dimensional periodic structure.

[0008] (5) A method utilizing the fine processing for each layer (KA McIntosh, et al., Appl. Phys. Lett., Vol. 7)
0, no. 22, pp. 2937-2939) In this method, a two-dimensional periodic structure is formed by forming a thin film, lithography, and dry etching for each layer, and the process is repeated to form a three-dimensionally stacked photonic. It forms a crystal.

(6) Method using multilayer bias sputtering (Kawakami et al., IEICE, CI, vol. J80-CI, no. 6,
pp. 296-299, 1997) In this method, a fine structure is formed on a substrate in advance, and silicon and carbon dioxide are alternately laminated on the substrate. A three-dimensional photonic crystal reflecting the above fine structure is formed.

In the above methods (3) to (6), a crystal is obtained by arranging a small volume element having a large refractive index in a medium having a small refractive index in a face-centered cubic structure. Its expression has been shown theoretically and experimentally.

[0011]

However, the above-mentioned conventional manufacturing method has the following problems to be solved.

First, in the above methods (1) to (3), although a photonic crystal can be produced, it is technically difficult to introduce a non-uniform portion which disturbs the periodic structure in the crystal. It is not suitable for practical device fabrication.

[0013] Next, the method (4) can introduce a portion having a non-uniform period at the time of producing a two-dimensional periodic structure, and is considered promising in terms of device production. In addition, a lithography process, a dry etching process, and a wafer fusion process are required for each layer, and the production process is complicated and takes a long time, so that there is a practical problem in processing a large number of substrates.

In the method (5), it is possible to introduce an uneven portion in the three-dimensional periodic structure as in the method (4). Three processes of dry etching are required, and there is a problem in manufacturing time.

Furthermore, the method (6) is the most promising at present because the fabrication process is simple and the material is a combination of silicon and silicon dioxide. Is easy in the stacking direction (direction perpendicular to the substrate), but not so easy in the horizontal direction (direction parallel to the substrate).

Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a method of manufacturing a two-dimensional and three-dimensional photonic crystal in which an uneven portion can be easily introduced and which can be easily manufactured.

[0017]

In order to solve the above-mentioned problems, a method for producing a two-dimensional photonic crystal according to the present invention has a laminated structure in which thin films are laminated on a substrate. A method for manufacturing a photonic crystal, comprising: forming a fine structure having a periodic two-dimensional arrangement on the substrate; and forming a thin film made of a material having a refractive index n1 (a material having a first refractive index) on the substrate. Forming a thin film on the structure; and pushing the thin film into the fine structure.

Further, according to the second aspect of the present invention,
The method for manufacturing a two-dimensional photonic crystal is a method for manufacturing a photonic crystal having a stacked structure in which thin films are stacked on a substrate, wherein a thin film made of a material having a refractive index n1 is formed on a first substrate. And forming a periodic two-dimensionally arranged fine structure on the second substrate, and pressing the fine structure on the second substrate into the thin film on the first substrate. It is characterized by the following.

In any of the above two-dimensional photonic crystal fabrication methods, it is preferable that the substrate be made of a material having a refractive index lower than that of the thin film. The microstructure preferably has a non-periodic part in a part of the periodic two-dimensional arrangement. The method for manufacturing a two-dimensional photonic crystal may further include a post-process of removing the substrate.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a three-dimensional photonic crystal having a stacked structure in which a plurality of thin films are stacked on a substrate. Forming a first thin film made of a first material having a refractive index n1, pressing a mold having a predetermined microstructure against the first thin film, and engraving the first thin film; On the first thin film, a refractive index n
Laminating a second thin film made of a second material having a refractive index of 2 (a material having a second refractive index), and stamping the second thin film with a mold having a predetermined microstructure. Is repeated at least once to form the laminate structure. Preferably, the method further includes a step of removing one of the first thin film and the second thin film.

According to an eighth aspect of the present invention, there is provided a method of manufacturing a three-dimensional photonic crystal having a stacked structure in which a plurality of thin films are stacked on a substrate. At least one step of forming a first thin film made of a first material having a refractive index n1 and laminating a second thin film made of a second material having a refractive index n2 on the first thin film is performed. Repeat the first
Forming a layered structure in which thin films of the above and the second thin film are alternately laminated, and stamping by pressing a mold having a predetermined fine structure against the layered structure. It is characterized by the following. Preferably, the method further comprises a step of removing one of the first thin film and the second thin film. Preferably, a fine structure having a periodic two-dimensional arrangement is used as the predetermined fine structure. Preferably, the predetermined microstructure has an aperiodic part in a part of the periodic two-dimensional arrangement.

Either of the materials having the first or second refractive index is made of an oxide or an oxide composite material.

As the oxide or oxide composite material,
Titanium, silicon, hydrogen, lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, cerium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, ruthenium, osmium, Cobalt, nickel, palladium, platinum, copper, silver, gold, zinc, cadmium, boron, aluminum, gallium, indium, thallium, carbon,
Those containing one or more elements such as germanium, tin, lead, nitrogen, phosphorus, arsenic, antimony, bismuth, sulfur, selenium, tellurium, fluorine, chlorine, bromine, and iodine can be used. It is generally known that an oxide or an oxide composite material containing the above element has a refractive index in the range of 1.3 to 3.0, and the first or second oxide is used so that the refractive index difference is as large as possible. It is preferable to use it as a material having a refractive index.

Either of the materials having the first or second refractive index is an organic polymer material. Examples of the organic polymer material include polyimide and photosensitive resin.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Method of Manufacturing Two-Dimensional Photonic Crystal> Hereinafter, an embodiment of a two-dimensional photonic crystal according to the present invention will be described in detail with reference to the drawings. The same reference numerals in the drawings denote the same components even in different drawings.

[First Embodiment] FIG. 1 is a view for explaining an example of a method for manufacturing a two-dimensional photonic crystal according to the present invention. FIGS. It is a typical sectional view for explaining. FIGS. 5 and 7 are schematic perspective views of an example of a structure having a two-dimensional uniform periodic structure used in such a manufacturing method. FIG.
In (a), the structure 14 (FIG. 5) or the structure 15 (FIG. 7) has one surface on which a periodic concavo-convex structure is formed along a two-dimensional direction (in a grid shape when viewed from a direction perpendicular to the surface). (Uneven structure formed). First, Figure 1
A structure 11 having a two-dimensional uniform periodic structure (see FIGS. 5 and 7) is manufactured as shown in FIG. Thereafter, a thin film of the material 12 having the refractive index n1 is formed on the structure 11. When the thin film is formed, the material 12 having the refractive index n1 is buried also in the fine structure of the structure 11, but when the fine structure is deep, the material 12 is usually not completely buried in FIG.
Voids and the like are generated as shown in FIG. Then, in order to complete the filling, after the formation of the thin film, the thin film is uniformly pressed into the fine structure by an appropriate external force (FIG. 1B). At this time, the material 12 having the refractive index n1 is compressed to increase the density, and in general, the refractive index increases, and the refractive index difference from the structure increases, which is advantageous in manufacturing a photonic crystal. By the above two steps, if the structure 11 is made of a material having a refractive index n0, a material having a refractive index n1 is two-dimensionally and periodically arranged in the material having a refractive index n0. A two-dimensional photonic crystal is manufactured (FIG. 1C). Further, in FIG. 1C, the structure 1
If 1 is removed, a photonic crystal having a structure in which a material having a refractive index n1 is two-dimensionally and periodically arranged in air (refractive index: about 1) is obtained (FIG. 1D). In this case, since the refractive index of air is about 1, the difference in refractive index can be increased, and structurally, it can be used irrespective of optical characteristics such as refractive index and light transmittance. There are advantages such as spreading. Further, in this case, it is preferable that the structure 12 is used repeatedly as a mold. FIG. 6 shows an example of a two-dimensional photonic crystal obtained by using a structure having a two-dimensional uniform period fine structure shown in FIG. 5 or 7 and embedding and removing a material having a refractive index n1.
Alternatively, it is shown in FIG. The microstructure patterns of the structures of FIGS. 5 and 7 are inverted (the concave portions of the structure 14 of FIG.
Corresponding to the projections of the structure 15), and the produced photonic crystals are obtained by inverting each other. Each of the functions as a photonic crystal shows a light filtering action.
That is, light of a certain wavelength can be transmitted based on the periodic structure of the photonic crystal and the refractive index difference, but light of other wavelengths cannot be transmitted (in FIGS. 6 and 8, light of wavelengths 1 and 2 respectively). ).

Next, a method for introducing a non-uniform portion that disturbs the period into the two-dimensional periodic structure will be described. In order to introduce a non-uniform portion, a structure in which a non-uniform portion is provided in a part of a structure 11 having a two-dimensional fine periodic structure in step (a) of FIG. 1 is used. FIGS. 9, 11, and 1 show examples of a structure provided with such an uneven portion.
3 or 15. In FIG. 9, a part of the two-dimensional periodic structure is filled with a concave portion, and a part of the two-dimensional periodic structure is provided with an uneven portion. In other words, the structure 16 has a structure in which a so-called tuning-fork-shaped convex portion in which one T-shape and two L-shapes are combined as viewed from above is present as an uneven portion. FIG. 10 shows a schematic perspective view of a two-dimensional photonic crystal made of the material 12 having the refractive index n1 manufactured by such a structure 16 (shown after the structure 16 is removed in the figure). In the two-dimensional photonic crystal of this example, a waveguide that enables T-shaped branching of light and bending at 90 degrees can be manufactured.
On the other hand, in the example of FIG. 11, a structure 17 having a structure in which the pattern is reversed from that of the structure 16 of FIG. FIG. 12 shows an example of a photonic crystal manufactured using this structure 17. The function as a photonic crystal is equivalent to that of FIG. FIG. 13 shows an example of a structure 18 in which a part of the concave portion is embeded in a circular shape to introduce an uneven portion.
FIG. 14 shows an example of a two-dimensional photonic crystal. In this case, light can be confined (light guided) in a direction parallel to the two-dimensional microstructure of the material 12 having the refractive index n1. The structure 19 in FIG. 15 has a reciprocal pattern relationship with the structure 18 in FIG. 13 similarly to the relationship between FIGS. 9 and 11, and the function of the photonic crystal has a two-dimensional fine structure as in FIG. The light is confined (light guided) in a direction parallel to FIG.
6).

A semiconductor lithography technique and a fine processing technique can be applied to manufacture a structure having a two-dimensional fine structure. Lithography means include ultraviolet light,
Electron beams and X-rays can be used. As a simple method, there is an anodization method using a stamping method, which has been recently developed (H. Masuda, et al., Appl. Phys. Le.
tt., vol. 71, no. 19, pp. 2770-2772, 1997). In this method, first, a mold having a predetermined fine structure is pressed on an aluminum substrate or the like to form a fine pattern depression on the surface of the substrate, and then anodic oxidation is performed. At this time, the dents serve as starting points and oxidation proceeds to reflect the fine structure of the above-mentioned type, so that a finely arranged fine structure can be manufactured on an aluminum substrate.

The structure 11 may be an integrated structure obtained by processing a two-dimensional fine structure on a single substrate as shown in FIG. 1A, or the fine structure may be formed as shown in FIG. It may be in a form penetrating the substrate. Alternatively, as shown in FIG. 4, it may be composed of a penetrating substrate 11a and a flat plate 11b.

For forming a thin film of a material having a refractive index n1 on the above-mentioned structure, a sputtering method, a vacuum deposition method, a chemical vapor deposition method, or the like can be applied. However, from the viewpoint of simplification of the process, sol-gel is used. The spin coating method using the method is most preferable.
The sol-gel method is, for example, as described in detail in “Application of the sol-gel method” by Sakubana Mio (Agune Jyofusha, 1997), by applying heat or heat to a previously prepared solution or dispersion of a thin film material. Light is used to cause a chemical reaction to solidify. In this method, since the starting material is a liquid, there is an advantage that thin films of various composite materials including glass materials can be formed by spin coating and at a relatively low temperature. In addition, since a soft thin film can be obtained by appropriately controlling the components and the production process, the thin film can be pushed into the microstructure by an appropriate external force.

Further, the refractive index n1 obtained in FIG.
In the case where it is difficult to handle a two-dimensional microstructure made of a material having the following characteristics due to insufficient strength or the like, a substrate supporting the two-dimensional microstructure may be provided, and the configuration shown in FIG. 2C shown in the second embodiment may be adopted. .

[Second Embodiment] FIGS. 2A to 2C illustrate a second example of a method for manufacturing a two-dimensional photonic crystal according to the present invention. It is a typical sectional view for explaining each process.

Hereinafter, a method for fabricating the two-dimensional photonic crystal of this embodiment will be described.

First, a thin film of the material 12 having the refractive index n1 is formed on the substrate 13 (FIG. 2A). Next, a structure 4 (FIG. 5) or a structure 15 (FIG. 7) having a two-dimensional uniform periodic structure similar to that of the first embodiment is manufactured and pressed against the thin film to form the material in the structure. 12
Is embedded (FIG. 2B). According to these two steps, if the structure 11 is made of a material having a refractive index n0, a material having a refractive index n1 is two-dimensionally and periodically arranged in the material having a refractive index n0. A photonic crystal is produced. Further, in FIG. 2B, if the structure 11 is removed, the refractive index n1 in air (about 1).
A photonic crystal having a structure in which the above materials are arranged two-dimensionally and periodically is obtained (FIG. 2C). In this case, since the refractive index of air is about 1, the refractive index difference can be increased, and the structure 12 can be used irrespective of optical characteristics such as the refractive index and light transmittance, so that there is no room for material selection. The first advantage is that the structure 12 is preferably used repeatedly as a mold.
This is as described in the embodiment.

In this embodiment, the introduction of the non-uniform portion into the two-dimensional periodic structure can be performed in the same manner as in the first embodiment. That is, instead of the structures 14 (FIG. 5) and 15 (FIG. 7) having a two-dimensional uniform periodic structure, structures 16 to 19 (FIGS. 9, 11, and 13) having non-uniform portions in the uniform periodic structure. , FIG. 15) may be used.
The functions of the photonic crystal are the same as those of the first embodiment.

The manufacturing process can be performed according to the first embodiment. However, in the present embodiment, the refractive index n1
Since the structure 11 is pressed against the thin film of the material 2 having the following and embedded in the structure, the object to be pressed is opposite to that of the first embodiment. Further, in order to facilitate the embedding process, it is preferable to perform the process while heating and softening the material 12.

An example in which a two-dimensional photonic crystal is specifically manufactured based on the method of any of the first and second embodiments will be described below.

[Example 1] A two-dimensional photonic crystal was manufactured by a manufacturing method based on the first embodiment.

Here, a silicon dioxide substrate (refractive index: about 1.4) finely processed by lithography as a structure having a two-dimensional fine structure, and a titanium oxide composite material (refractive index: about 1.4) as a material having a refractive index n1. Using 2.5), a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a chromium thin film was formed on a silicon dioxide substrate, and a resist was spin-coated and heat-treated. Next, the resist was exposed to an electron beam and developed to form a microstructure pattern (0.4 μm square pattern, pattern area 2 mm) having a period of 0.8 μm. In this electron beam exposure, FIG.
The fine structures of the six types of structures shown in FIGS. 7, 9, 11, 13 and 15 were exposed on one silicon dioxide substrate. Next, the chromium thin film was etched by reactive dry etching using a gas containing a halogen element, using the resist pattern as a mask. Then, the chromium thin film pattern is used as a mask to etch a silicon dioxide substrate using a gas containing a halogen element to a depth of 2 μm.
A silicon dioxide structure having a two-dimensional microstructure was fabricated.

Next, a titanium oxide composite material solution was spin-coated on the silicon dioxide structure to form a thin film of the titanium oxide composite material on the fine structure of silicon dioxide.
Then, after performing a heat treatment, the titanium oxide composite material film was uniformly pressed using a flat plate to ensure embedding in the fine structure. Thereafter, heat treatment was performed to solidify the titanium oxide composite material film. As a result, a two-dimensional uniform periodic structure and a two-dimensional periodic structure including non-uniform portions of the titanium oxide composite material arranged in the silicon dioxide substrate were produced.

Example 2 A two-dimensional photonic crystal was manufactured by the manufacturing method based on the first embodiment.

Here, a resist film finely processed by lithography as a structure having a two-dimensional fine structure and a titanium oxide composite material (refractive index about 2.5) as a material having a refractive index n1 are used. A two-dimensional periodic structure including a uniform periodic structure and a non-uniform part was manufactured.

First, a photoresist is spin-coated on a silicon substrate by 1 μm, heat-treated, exposed through a mask previously produced by an ultraviolet reduction projection exposure apparatus, developed, and developed to form a 0.8 μm periodic pattern (0.4 μm square). , Pattern area 2 mm). In this exposure, FIGS.
The fine structures of the six types of structures shown in FIGS. 9, 11, 13, and 15 were collectively exposed and developed to form a resist pattern. Thus, a resist structure having a two-dimensional fine structure was manufactured. Next, after the resist pattern was ultraviolet-cured, a titanium oxide composite material solution was spin-coated on the fine structure of the resist to form a thin film of the titanium oxide composite material on the fine structure of the resist. Then, after performing a heat treatment, the titanium oxide composite material film was uniformly pressed using a flat plate to ensure embedding in the fine structure. Thereafter, heat treatment was performed to solidify the titanium oxide composite material film. During the heat treatment, the resist as a structural body partially decomposed and disappeared, but the resist was completely removed by using a resist etching solution. Thereby, the two-dimensional uniform periodic structure of the titanium oxide composite material and the two-dimensional
A two-dimensional periodic structure was fabricated.

Example 3 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the first embodiment.

Here, as a structure having a two-dimensional fine structure, an aluminum substrate having a fine structure formed by anodization is used, and a titanium oxide composite material (refractive index: about 2.5) is used as a material having a refractive index n1. A two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a pattern of 0.8 μm periodic structure (0.4 μm hexagon, pattern area 2 mm) was formed on the aluminum substrate by the highly-aligned anodic oxidation method described in the first embodiment. The pattern depth was 5 μm. At this time, by appropriately processing the mold used for embossing the aluminum substrate, the fine structures of the three types of structures shown in FIGS. 5, 9 and 13 are formed on a single aluminum substrate to form a two-dimensional structure. An aluminum structure having a fine structure was manufactured. Next, a composite material solution of titanium oxide was spin-coated on the aluminum structure to form a thin film of the titanium oxide composite material on the fine structure of the aluminum structure. Then, after performing a heat treatment, the titanium oxide composite material film was uniformly pressed using a flat plate to ensure embedding in the fine structure. Thereafter, heat treatment was performed to solidify the titanium oxide composite material film. Furthermore, a two-dimensional uniform periodic structure and a periodic structure having a non-uniform portion of the titanium oxide composite material were produced by eluting the aluminum structure with an etchant.

Example 4 A two-dimensional photonic crystal was manufactured by the manufacturing method based on the first embodiment.

Here, a silicon dioxide substrate (refractive index: about 1.4) finely processed by lithography as a structure having a two-dimensional microstructure and lead zirconate titanate (hereinafter, referred to as a material having a refractive index n1). Called PZT.
Using a refractive index of about 2.6), a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a chromium thin film was deposited on a silicon dioxide substrate, and a resist was spin-coated and heat-treated. Next, the resist is exposed to an electron beam and developed to form a fine structure pattern having a period of 0.8 μm (0.4 μm square, pattern area 2 m).
m) was formed. In this electron beam exposure, FIGS.
The fine structures of the six types of structures shown in FIGS. 9, 11, 13 and 15 were exposed on one silicon dioxide substrate. Next, the chromium thin film was etched by reactive dry etching using a gas containing a halogen element, using the resist pattern as a mask. Next, a silicon dioxide structure having a two-dimensional fine structure was prepared by etching the silicon dioxide substrate using the chromium thin film pattern as a mask and using a gas containing a halogen element at a depth of 2 μm.

Thereafter, P is formed on the silicon dioxide structure.
The ZT solution was spin-coated to form the PZT thin film on the fine structure of silicon dioxide. Thereafter, after performing a heat treatment, the PZT film was uniformly pressed using a flat plate to ensure embedding in the fine structure. Thereafter, heat treatment was performed to solidify the PZT film. Thus, a two-dimensional periodic structure of PZT disposed in the silicon dioxide substrate and a two-dimensional periodic structure including a non-uniform portion were produced.

Example 5 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the first embodiment.

Here, a two-dimensional uniform periodic structure is formed using a resist thin film finely processed by lithography as a structure having a two-dimensional fine structure and PZT (refractive index about 2.6) as a material having a refractive index n1. , And a two-dimensional periodic structure including a non-uniform portion.

First, a photoresist is spin-coated on a silicon substrate by 1 μm, heat-treated, exposed through a mask previously prepared by an ultraviolet reduction projection exposure apparatus, developed, and developed to form a 0.8 μm periodic structure pattern (0.4 μm square square). , Pattern area 2 mm). In this exposure, FIGS.
The fine structures of the six types of structures shown in FIGS. 9, 11, 13, and 15 were collectively exposed and developed to form a resist pattern. Thus, a resist structure having a two-dimensional fine structure was manufactured. Next, after the resist pattern was cured by ultraviolet light, a PZT solution was spin-coated on the fine structure of the resist to form a thin film of the PZT on the fine structure of the resist. Then, after performing a heat treatment, the PZT film was uniformly pressed using a flat plate to ensure the filling in the fine structure. Thereafter, heat treatment was performed to solidify the PZT film. During the heat treatment, the resist as a structural body partially decomposed and disappeared, but the resist was completely removed by using a resist etching solution. Thus, a two-dimensional periodic structure including a two-dimensional uniform periodic structure and a non-uniform part of PZT was produced.

Example 6 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the first embodiment.

Here, an aluminum substrate having a fine structure formed by anodization as a structure having a two-dimensional fine structure and PZT (refractive index about 2.6) as a material having a refractive index n1 are used. A two-dimensional periodic structure including a uniform periodic structure and a non-uniform part was manufactured.

First, in the same manner as in Example 3, a 0.8 μm periodic structure pattern (0.4 μm hexagon, pattern area 2 mm) was formed on an aluminum substrate. The pattern depth was 5 μm. At this time, the mold used for embossing the aluminum substrate is appropriately processed so that the mold shown in FIGS.
The fine structures of the various types of structures were formed on a single aluminum substrate, and an aluminum structure having a two-dimensional fine structure was manufactured. Next, PZT is formed on the aluminum structure.
The solution is spin-coated and the P
A thin film of ZT was formed. Then, after performing a heat treatment, the PZT film was uniformly pressed using a flat plate to ensure the filling in the fine structure. Thereafter, heat treatment was performed to solidify the PZT film. Furthermore, a two-dimensional uniform periodic structure of PZT and a periodic structure having a non-uniform part were produced by eluting the aluminum structure with an etchant.

[Example 7] A two-dimensional photonic crystal was manufactured by a manufacturing method based on the first embodiment.

Here, a silicon dioxide substrate (refractive index 1.4) finely processed by lithography as a structure having a two-dimensional fine structure and selenium which is a kind of chalcogenite glass as a material having a refractive index n1 Using arsenic (refractive index: about 2.9, softening point: about 200 ° C.), a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a two-dimensional fine structure was processed on a silicon dioxide substrate by the method described in the first embodiment, and the six types of fine structures shown in FIGS. 5, 7, 9, 11, 13, and 15 were obtained. Was produced. Next, a thin film of arsenic selenide was formed on the silicon dioxide structure by a sputtering method. Next, the arsenic selenide film was uniformly pressed by using a flat plate while heating to ensure the embedding in the fine structure. Thereafter, heat treatment was performed to solidify the arsenic selenide film. Thus, a two-dimensional uniform periodic structure of arsenic selenide disposed in the silicon dioxide substrate and a two-dimensional periodic structure including a non-uniform portion were produced.

In this embodiment, arsenic selenide, which has a proven track record in the production of waveguides and the like, was used as a chalcogenide glass. Any material having high refractive index and low softening point is applicable.

Example 8 A two-dimensional photonic crystal was manufactured by the manufacturing method based on the first embodiment.

Here, an aluminum substrate having a fine structure formed by anodization as a structure having a two-dimensional fine structure, and arsenic selenide (a kind of chalcogenide glass having a refractive index of about 2 .9)
Was used to produce a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part.

First, a two-dimensional fine structure was processed on an aluminum substrate by the method described in the third embodiment, and FIGS.
An aluminum structure including the three types of microstructures indicated by was manufactured. Next, a thin film of arsenic selenide was formed on the aluminum structure by a sputtering method. Next, the arsenic selenide film was uniformly pressed by using a flat plate while heating to ensure the embedding in the fine structure. Thereafter, heat treatment was performed to solidify arsenic selenide. Furthermore, the aluminum structure was eluted with an etchant to produce a two-dimensional uniform periodic structure of arsenic selenide and a periodic structure having a non-uniform portion.

[Example 9] A two-dimensional photonic crystal was manufactured by the manufacturing method based on the second embodiment.

Here, a silicon dioxide substrate (refractive index: about 1.4) finely processed by lithography as a structure having a two-dimensional fine structure, and a titanium oxide composite material (refractive index: about 1.4) as a material having a refractive index n1. Using 2.5), a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a titanium oxide composite material solution was spin-coated on a silicon dioxide substrate and heat-treated to form a titanium oxide composite material thin film. Next, the silicon dioxide structure produced by the method described in Example 1 was pressed into the titanium dioxide composite material thin film, and the titanium dioxide composite material was embedded in the fine structure of the silicon dioxide structure. Thereafter, a heat treatment was performed to solidify the titanium dioxide composite material film. In this way, a two-dimensional periodic structure including a two-dimensional uniform periodic structure and a non-uniform part of the titanium dioxide composite material arranged in the silicon dioxide substrate was produced.

Example 10 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the second embodiment.

Here, as the structure having a two-dimensional fine structure, an aluminum substrate having a fine structure formed by anodization is used, and a titanium oxide composite material (refractive index: about 2.7) is used as a material having a refractive index n1. A two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a titanium oxide composite material solution was spin-coated on a silicon dioxide substrate and heat-treated to form a thin film of the titanium oxide composite material. Next, the aluminum structure produced by the method described in Example 3 was pressed into the titanium dioxide composite material thin film, and the titanium dioxide composite material was embedded in the fine structure of the aluminum structure. Thereafter, a heat treatment was performed to solidify the titanium dioxide composite material film. Furthermore, by eluting the aluminum structure with an etchant,
A two-dimensional uniform periodic structure and a periodic structure having a non-uniform portion of a titanium oxide composite material were fabricated.

Example 11 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the second embodiment.

Here, a silicon dioxide substrate (refractive index: about 1.4) finely processed by lithography as a structure having a two-dimensional fine structure, and PZT (refractive index: about 2.6) as a material having a refractive index n1. ) To produce a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform portion.

First, a PZT solution was spin-coated on a silicon dioxide substrate and heat-treated to form a PZT thin film. Next, the silicon dioxide structure produced by the method described in Example 1 was pushed into the PZT film, and PZT was embedded in the fine structure of the silicon dioxide structure. Thereafter, heat treatment was performed to solidify the PZT film. Thus, a two-dimensional periodic structure of PZT disposed in the silicon dioxide substrate and a two-dimensional periodic structure including a non-uniform portion were produced.

[Example 12] A two-dimensional photonic crystal was manufactured by the manufacturing method based on the second embodiment.

Here, an aluminum substrate having a fine structure formed by anodization as a structure having a two-dimensional fine structure and PZT (refractive index: about 2.6) as a material having a refractive index n1 are used. A two-dimensional periodic structure including a uniform periodic structure and a non-uniform part was manufactured.

First, a PZT solution was spin-coated on a silicon dioxide substrate and heat-treated to form a PZT thin film. Next, the aluminum structure manufactured by the method described in Example 3 was pushed into the PZT film, and PZT was embedded in the fine structure of the aluminum structure. After that, heat treatment is performed and P
The ZT film was solidified. Furthermore, a two-dimensional uniform periodic structure of PZT and a periodic structure having a non-uniform part were produced by eluting the aluminum structure with an etchant.

Example 13 A two-dimensional photonic crystal was manufactured by a manufacturing method based on the second embodiment.

Here, a silicon dioxide substrate (refractive index: about 1.4) finely processed by lithography as a structure having a two-dimensional fine structure, and selenide, a kind of chalcogenide glass, as a material having a refractive index n1 Using arsenic (refractive index: about 2.9), a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part were produced.

First, a thin film of arsenic selenide is formed on a silicon dioxide substrate by a sputtering method. Next, the silicon dioxide structure produced by the method described in Example 1 was pressed while heating the arsenic selenide thin film and the thin film to embed arsenic selenide in the fine structure of the silicon dioxide structure. Thereafter, heat treatment was performed to solidify arsenic selenide.
Thus, a two-dimensional uniform periodic structure of arsenic selenide disposed in the silicon dioxide substrate and a two-dimensional periodic structure including a non-uniform portion were produced.

[Example 14] A two-dimensional photonic crystal was manufactured by a manufacturing method based on the second embodiment.

Here, an aluminum substrate having a fine structure formed by anodic oxidation as a structure having a two-dimensional fine structure, and arsenic selenide (a kind of chalcogenide glass having a refractive index of about 2 .9)
Was used to produce a two-dimensional uniform periodic structure and a two-dimensional periodic structure including a non-uniform part.

First, a thin film of arsenic selenide is formed on a silicon dioxide substrate by a sputtering method. Next, the aluminum structure produced by the method described in Example 3 was pressed against the arsenic selenide thin film while heating the thin film to embed arsenic selenide in the fine structure of the silicon dioxide structure. Thereafter, heat treatment was performed to solidify arsenic selenide. Furthermore, the aluminum structure was eluted with an etchant to produce a two-dimensional uniform periodic structure of arsenic selenide and a periodic structure having a non-uniform portion.

<Method of Manufacturing Three-Dimensional Photonic Crystal> Next, a three-dimensional photonic crystal according to the present invention will be described in detail.

[Third Embodiment] FIGS. 17A to 17D illustrate an example of a method of manufacturing a three-dimensional photonic crystal based on the present invention. FIGS. It is a typical sectional view for explaining. FIG.
FIG. 8 is a perspective view of a mold used in such a manufacturing method. In FIG. 17A, the mold 4 is formed in a lattice shape when viewed from a direction perpendicular to the surface on which an uneven structure (hereinafter also referred to as a two-dimensional periodic structure) is formed periodically along a two-dimensional direction. Uneven structure). That is, a plurality of rectangular protrusions are arranged in a grid on one surface of the mold 4.

First, as shown in FIG. 17A, a thin film 2 made of a first material having a first refractive index (n1) is laminated on a substrate 1. Then, mold 4 (FIG. 17 (a)
Is pressed against the upper surface of the thin film 2 to imprint the uneven structure (hereinafter, also referred to as a two-dimensional periodic structure) on the surface of the thin film 2 (FIG. 17B). On the thin film 2 on which the two-dimensional periodic structure is formed, a second refractive index (n
The thin film 3 made of the second material having 2) is laminated (FIG. 17C). Thereafter, the two-dimensional periodic structure is formed on the surface of the thin film 3 by engraving with the mold 4 as in the case of the thin film 2 (FIG. 17D). At this time, a two-dimensional periodic structure different from the two-dimensional periodic structure applied to the thin film 2 can be applied. In this manner, the thin films 2 and 3 having different refractive indexes are alternately stacked while forming a two-dimensional periodic structure, thereby forming a stacked body.

FIG. 19 shows a thin film 2 having a two-dimensional periodic structure.
And FIG. 3 is a perspective view of a three-dimensional photonic crystal formed of a laminate in which a laminate is formed on a substrate. In this figure, thin films 2 and 3 having a two-dimensional periodic structure are alternately laminated five times on a substrate to form a laminate having a three-dimensional fine periodic structure.

In the following description, one thin film 2 and 1
Laminating the two thin films 3 is defined as one cycle of forming a laminated body. Therefore, for example, in the case of the third cycle lamination,
This means that one thin film 2 and one thin film 3 are further stacked on a laminate already formed by alternately stacking two thin films 2 and two thin films 3.

Next, a method of introducing a non-uniform portion that disturbs the period into the periodic structure of such a laminate will be described.

In order to introduce a non-uniform portion, a mold having a non-uniform portion in a part of the two-dimensional periodic structure is used in forming the laminate. FIG. 20 shows an example of a mold provided with such an uneven portion. In this figure, a mold 5 having a non-uniform part in a part of the two-dimensional periodic structure is obtained by lacking one convex part located at the center of a lattice pattern formed by a plurality of convex parts. That is, the mold 5 is a mold in which a cross-shaped concave portion exists as an uneven portion when viewed from above. FIG. 21 shows an example of a laminate imprinted with such a mold 5. The shape of the non-uniform portion is not limited to a specific shape, but may be any shape such as a circular shape, a rectangular shape, an L-shaped shape, an X-shaped shape, etc. It is. For example, FIG. 22 shows a mold 6 in which an uneven portion is formed by removing a plurality of convex portions in an L shape.

FIGS. 23 and 24 show examples in which the fifth period of the two-dimensional periodic structure is formed using the molds 5 and 6, respectively, when forming the laminate of FIG. As shown in the figure, a non-uniform two-dimensional periodic structure is formed on the thin film 3 having the second refractive index located as the uppermost layer of the laminate. Further, by using not only the fifth period but also a mold having non-uniform portions continuously, it is possible to provide a laminate in which non-uniform portions are formed in the vertical direction. Also,
It is also possible to further laminate a two-dimensional uniform periodic structure 4 or a non-uniform periodic structure 5 or 6 in six or seven periods on the uppermost layer of the laminate of FIG. 21 or FIG.

For the above-described thin film formation, a sputtering method, a vacuum deposition method, a chemical vapor deposition method, or the like can be applied. Among them, the spin coating method using the sol-gel method is most preferable from the viewpoint of simplification of the process. The sol-gel method is, for example, as described in "Application of the sol-gel method" by Agio Sakubana (published by Agne Shofu, 1997). Heat and light are applied to cause a chemical reaction to solidify. In this method, since the starting material is a liquid, there are advantages that a uniform thin film can be obtained by spin coating and thin films of various composite materials such as glass and ceramics can be easily obtained at a relatively low temperature. is there. In addition, by appropriately controlling the components and the production process, a soft gel film can be obtained, so that a fine pattern can be formed at room temperature by the engraving method. In the direct pattern formation by the engraving method using the sol-gel method spin coating film, a compact disk or the like having a groove of a submicron pattern has already been manufactured. Technically, it is in the range that is possible.

On the other hand, a device called a stamper, which is currently used in the manufacture of compact discs, can be used for engraving. In the manufacture of a compact disc, the process is usually completed by one stamping, but when applied to the production of a three-dimensional photonic crystal based on the present invention,
Since it is necessary to repeat the engraving process, the overlay accuracy between layers is important. In order to obtain a good photonic crystal, the overlay accuracy needs to be at least 0.05 μm or less. For this purpose, it is promising to apply some alignment technology used in lithography technology for manufacturing semiconductors, in particular, X-ray lithography technology. X
Line lithography is a 1: 1 exposure method in which a mask and a wafer are brought close to several tens of μm, and the mask pattern dimension is transferred to the wafer at a ratio of 1: 1. High technical compatibility. Since the overlay accuracy of the current X stepper is about 0.02 μm, if this technology is diverted, it is possible to laminate a three-dimensional periodic structure with an accuracy of 0.05 μm or less.

The mold can be manufactured by using an electron beam lithography technique and a dry etching technique in the same manner as a photomask and an X-ray mask currently used in semiconductor lithography. As the substrate for the mold, a hard and highly resistant one is preferable, and silicon carbide,
Substrates made of quartz, silicon, silicon dioxide (by a thermal oxidation method, a sputtering method, or a chemical vapor method), artificial diamond, stainless steel, nickel, ceramic, and the like can be given.

[Fourth Embodiment] FIGS. 24A and 24B are diagrams for explaining a fourth example of a method of manufacturing a three-dimensional photonic crystal according to the present invention. FIGS. It is a typical sectional view for explaining each process. This embodiment is characterized in that a three-dimensional periodic structure is formed by imprinting a plurality of thin films once. Therefore, not only can the thin film forming method and the mold used for engraving be the same as those in the first embodiment, but also the photonic crystal manufacturing process can be greatly simplified. It is.

Hereinafter, a method for fabricating the three-dimensional photonic crystal of this embodiment will be described.

First, a thin film 2 made of a material having a first refractive index is laminated on a substrate 1. Next, a thin film 3 made of a material having a second refractive index is laminated on the thin film 2. Further, the thin films 2 and 3 are alternately laminated,
Finally, an alternate laminated film in which three thin films are formed is formed.

As shown in FIG. 24 (a), the mold shown in FIG. 18 is pressed against the alternately laminated film thus formed from above the alternately laminated film as shown in FIG. Marks a two-dimensional fine periodic structure. As a result, as shown in FIG. 24B, a three-dimensional periodic structure is formed in the stacked body including the thin films 2 and 3.

The introduction of the non-uniform part into the three-dimensional periodic structure is as follows.
As in the third embodiment, it can be easily performed by changing the mold. An example of introducing an uneven portion parallel to the substrate will be described below. Note that, similarly to the third embodiment, a mold having an arbitrary shape can be used in the present embodiment.

First, stamping after three-period lamination is performed by the mold 4 having a uniform fine periodic structure shown in FIG. Next, the thin film of the material having the first or second refractive index in the fourth cycle is marked by using, for example, the mold 5 or 6 in FIG. 20 or FIG. Thereafter, the films are alternately stacked again and stamped with the mold 4 in FIG. 18 to form an uneven portion in any layer.

When introducing a non-uniform portion in a direction perpendicular to the substrate, stamping after three cycles of lamination is performed using, for example, a mold 5 or 6 shown in FIG. 20 or FIG.

As described above, in the present embodiment, the introduction of the non-uniform portion into the three-dimensional periodic structure can be realized by performing the marking process at least three times. As a result, the manufacturing process of the three-dimensional photonic crystal can be greatly simplified, and the overlay accuracy can be greatly improved.

[Fifth Embodiment] FIG. 25 is a view for explaining a fifth example of a method of manufacturing a three-dimensional photonic crystal according to the present invention. FIGS. It is a typical sectional view for explaining each process.

Hereinafter, a method for fabricating the three-dimensional photonic crystal of this embodiment will be described.

First, a thin film 2 made of a material having a first refractive index is laminated on a substrate 1. Next, FIG.
A two-dimensional fine periodic structure is stamped by pressing a mold 4 similar to that shown in FIG. 25 from above the laminated film as shown in FIG. 25A (FIG. 25B).

On the thin film 2 on which the two-dimensional periodic structure is formed, a thin film 3 made of a material having a second refractive index is laminated. Thereafter, it is stamped using a mold 4b (reference numeral 4 'in FIG. 25) of FIG. 26 having a fine periodic structure similar to that of the mold shown in FIG. 18 and forming a convex support around the fine periodic structure. (FIGS. 25C to 25D). FIG. 26 shows an example of a mold for forming a support portion. The mold 4b includes an uneven portion that contributes to the formation of a fine periodic structure, and a convex portion that stands around the uneven portion at a predetermined distance from the uneven portion. The height of the protrusions of the concavo-convex portions contributing to the formation of the fine periodic structure is slightly lower than the height of the protrusions for forming the pillar portions. The strut pattern formed by the strut forming die (that is, the thin film portion engraved by the protrusion) is for forming a strut having a three-dimensional structure. Therefore, it is desirable that the thin film portion imprinted by the projections be as thin as possible.

Next, the thin film 2 is laminated on the thin film 3 engraved with the mold 4b, and a mold 4 similar to that shown in FIG.
(FIG. 25 (e)).

In the laminated structure thus formed, the thin film 3 made of the material having the second refractive index is removed to form voids. Thus, a three-dimensional periodic structure including the thin film 2 made of the material having the first refractive index and the air is formed. In this case, it is important to control the mold and the engraving so that a sufficient strength is maintained even in a narrow portion of the corner of the periodic structure pattern.

FIG. 27 is a perspective view showing a three-dimensional laminate structure after five periods of lamination. The introduction of the non-uniform portion into the three-dimensional periodic structure can be performed in the same manner as in the first and second embodiments. FIG. 28 and FIG. 29 are perspective views showing an example when an uneven portion is introduced.

[Sixth Embodiment] FIG. 30 is a view for explaining a sixth example of a method of manufacturing a three-dimensional photonic crystal according to the present invention. It is a typical sectional view for explaining each process.

First, a thin film 2 made of a material having a first refractive index is laminated on a substrate 1 and stamped with a mold 4 similar to that shown in FIG. 18 (FIGS. 30A and 30B). . Further, a thin film 3 made of a material having a second refractive index is laminated on the marked thin film 2 and stamped with a mold 4 (FIG. 30C).

A resist 9 is further applied on the laminate on which the two-dimensional periodic structure is formed by the engraving, and ultraviolet rays 8 are irradiated through a photomask 7 to form a thin film 3 made of a material having a second refractive index. The peripheral portion of the fine structure is removed (FIG. 30D).

Subsequently, a thin film 2 made of a material having a first refractive index is laminated and stamped with a mold 4 (FIG. 30).
(E)).

In the laminated structure thus formed, the thin film 3 made of the material having the second refractive index is removed to form a void (FIG. 30 (f)). Thus, a three-dimensional periodic structure including the thin film 2 made of the material having the first refractive index and the air is formed. In this case, it is important to control the mold and the engraving so that a sufficient strength is maintained even in a narrow portion of the corner of the periodic structure pattern. It is also important that the spacing between the columns is a distance that does not affect the characteristics of the photonic crystal.

After the five-period lamination, the three-dimensional laminate structure
The structure shown in FIG. The introduction of the non-uniform portion into the three-dimensional periodic structure can be performed in the same manner as in the third and fourth embodiments. For example, as in the fifth embodiment, for example, FIGS. The structure shown in FIG.

[Seventh Embodiment] FIG. 31 is a view for explaining a seventh example of a method for producing a three-dimensional photonic crystal according to the present invention. It is a typical sectional view for explaining each process.

First, a thin film 2 made of a material having a first refractive index is laminated on a substrate 1. Next, a thin film 3 made of a material having a second refractive index is laminated on the thin film 2. Further, the thin films 2 and 3 are alternately laminated,
Finally, an alternate laminated film in which three thin films are formed is formed.

By pressing the mold 4 shown in FIG. 18 from above the alternately laminated film as shown in FIG. 31A against the alternately laminated film thus formed, a two-dimensional fine periodic structure is formed. Is engraved. As a result, a three-dimensional periodic structure is formed on the thin films 2 and 3 (FIG. 31B).

Subsequently, a photoresist is applied to the uppermost portion of the stamped laminated structure, and ultraviolet light 8 is irradiated through a photomask 7, thereby to form a peripheral portion of the fine structure of the thin film 3 made of a material having the second refractive index. Remove the part. further,
Using the thin film 3 patterned by ultraviolet irradiation as a mask, the alternately laminated structure is etched using a technique such as dry etching. After that, a material 2 ′ having the first refractive index is embedded in the etched portion (FIG. 31C).

By repeating the above steps ((a) to (c) in FIG. 31), an alternate laminated structure made of two kinds of materials having different refractive indexes can be obtained. A material having the first refractive index is preferable as a filling material of the etched portion, but another material can be used.

Finally, a portion of the material having the second refractive index is removed from the above-mentioned alternately laminated structure to form a gap (FIG. 3).
1 (d)). Thereby, a three-dimensional periodic structure including the material having the first refractive index and air is formed. In this case, it is important to control the mold and the marking so that sufficient strength is maintained, especially in the narrow corners of the periodic structure pattern. It is also important that the spacing between the columns is a distance that does not affect the characteristics of the photonic crystal.

After the five-period lamination, the three-dimensional laminated structure
As in the case of the sixth embodiment, the structure shown in FIG. 27 is obtained. The introduction of the non-uniform portion into the three-dimensional periodic structure can be performed in the same manner as in the third and fourth embodiments. For example, as in the fifth and sixth embodiments, FIG. And the structure shown in FIG.

[Other Embodiments] By changing the shape of the mold 4 used in the above embodiment, various three-dimensional periodic structures can be manufactured. Hereinafter, an example will be described with reference to the drawings.

FIGS. 32A to 32F illustrate a sixth example of a method for producing a three-dimensional photonic crystal according to the present invention. FIGS. 32A to 32F are schematic diagrams for explaining each step. FIG. FIG. 33 is a perspective view of a mold applied by this method. FIG. 34 is a perspective view showing a three-dimensional laminate structure created by this method.

First, a thin film 2 made of a material having a first refractive index is laminated on a substrate 1.

A two-dimensional fine periodic structure is imprinted on the thin film 2 by pressing a mold 4 shown in FIG. 33 from above the laminated film as shown in FIG. The mold 4 is different from the molds of the first to fifth embodiments in the shape of the unevenness. That is, a rectangular convex portion provided in parallel is used. Next, a thin film 3 made of a material having a second refractive index is laminated on the thin film 2 (FIG. 32B).

Subsequently, the thin film 2 is laminated, and the mold 4 is stamped again in a direction different from that of the first stamp by 90 degrees (FIG. 32 (c)).

Further, similarly, as shown in FIGS. 32 (d) and (e), by repeating lamination and engraving,
An alternate layered structure made of two types of materials having different refractive indexes can be obtained.

Finally, a portion (thin film 3) of the material having the second refractive index is removed from the above-mentioned alternately laminated structure to form a gap (FIG. 32 (f)). Thereby, a three-dimensional periodic structure including the material having the first refractive index and the air is formed (FIG. 34).

FIG. 35 is a view for explaining a seventh example of the method for producing a three-dimensional photonic crystal according to the present invention. FIGS. 35 (a) to (e) are schematic views for explaining each step. FIG. FIG. 36 is a perspective view of a mold applied by this method. FIG. 36 is a perspective view showing a three-dimensional laminated body structure produced by this production method.

First, a thin film 3 made of a material having a second refractive index is laminated on the substrate 1.

A two-dimensional fine periodic structure is stamped on the thin film 3 by pressing a mold 4 shown in FIG. 36 from above the laminated film as shown in FIG. The mold 4 is different from the molds of the first to fifth embodiments in the shape of the unevenness. That is, one having a plurality of square protrusions provided at equal intervals is used. Next, a thin film 2 made of a material having a first refractive index is laminated on the thin film 2 (FIG. 35B).

Subsequently, the thin films 3 are laminated, and engraving is performed with the mold 4 (FIG. 35C).

Further, similarly, as shown in FIG. 35 (d), by laminating the thin films 2, an alternate lamination structure composed of two kinds of materials having different refractive indexes can be obtained.

Finally, a portion (thin film 3) of the material having the second refractive index is removed from the above-mentioned alternately laminated structure to form a gap (FIG. 35 (e)). As a result, a three-dimensional periodic structure including the material having the first refractive index and the air is formed (FIG. 37).

An example in which a three-dimensional photonic crystal is specifically manufactured based on the method of any of the third to seventh embodiments will be described below.

[Example 15] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the third embodiment.

Here, as a material having the first refractive index, lead zirconate titanate (hereinafter referred to as PZT, which is an oxide composite material containing titanium, having a refractive index of about 2.6), which is an oxide composite material containing titanium, is used.
Using a silicon oxide composite material (refractive index: 1.4) as the material having the second refractive index, a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated, so that a 0.1 μm solution was formed on the silicon substrate.
A 2 μm thin film was formed. Next, after heat-treating this coating film on a hot plate, a mold having a 0.8 μm periodic structure (0.4 μm square pattern, pattern area of 2 mm) made of a silicon carbide substrate was pressed against the PZT thin film and stamped. A two-dimensional periodic structure having a depression having a depth of about 0.2 μm was formed. Then, heat on a hot plate,
The thin film having the two-dimensional periodic structure was solidified. Next, the silicon oxide composite material coating solution is spin-coated about 0.2 μm on the thin film having the two-dimensional PZT periodic structure, and heat-treated on a hot plate to form a mold having the 0.8 μm periodic structure on the silicon oxide. The thin film of the composite material was pressed against and stamped to form a two-dimensional periodic structure having a depression of about 0.2 μm. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. The above thin film formation,
The three-dimensional uniform periodic structure was produced by repeating the engraving process on each tenth floor.

Further, also in a three-dimensional periodic structure including a non-uniform portion, according to the manufacturing process of the third embodiment,
It was produced as follows. First, a PZT thin film of about 0.2 μm is formed on the 10-period three-dimensional uniform periodic structure manufactured as described above by the above-described method, and the center of the 0.8 μm periodic structure is formed as shown in FIG. After pressing and imprinting a mold having a non-uniform structure, the mold was heat-treated on a hot plate and solidified. Finally, on the non-uniform structure of PZT,
In the same manner as in the case where the above-described uniform periodic structure is manufactured, the .0.
1 μm of 2 μm silicon oxide composite material and 0.2 μm PZT
A zero-period uniform periodic structure was formed.

[Example 16] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the fourth embodiment.

Here, as the material having the first refractive index, lead zirconate titanate (refractive index: about 2.6), which is an oxide composite material containing titanium, and oxidized as the material having the second refractive index. Using a silicon composite material (refractive index: 1.4), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate, spin-coated, and heat-treated on a hot plate to form a PZT thin film of about 0.2 μm. Next, the PZ
An appropriate amount of a silicon oxide composite material coating solution was dropped on the T thin film, spin-coated, and heat-treated on a hot plate to form a silicon oxide composite material thin film of about 0.2 μm. This was repeated 10 times to form alternately laminated films of PZT and silicon oxide composite material for 10 cycles. Thereafter, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the above-mentioned alternately laminated film, stamped, and heated by a hot plate to solidify the alternately laminated film. Thus, a three-dimensional uniform periodic structure was formed.

Further, also in a three-dimensional periodic structure including a non-uniform portion, the same fabrication process as that of the second embodiment was performed as follows. First, the 3 prepared above
Approximately 0.2 μm P
After forming a ZT thin film and pressing and stamping a mold having a non-uniform structure (see FIG. 20) at the center used in Example 1,
It was solidified by heat treatment on a hot plate. Next, on the non-uniform structure of PZT, an alternately laminated film of 0.2 μm of silicon oxide composite material and 0.2 μm of PZT for 10 periods in the same manner as in the case of forming the above-mentioned uniform periodic structure. Was formed and stamped to form a uniform periodic structure.

[Embodiment 17] A three-dimensional photonic crystal was manufactured by the manufacturing method based on the third embodiment.

Here, as the material having the first refractive index, lead zirconate titanate (refractive index: about 2.6), which is an oxide composite material containing titanium, and oxidized as the material having the second refractive index. Using a silicon composite material (refractive index: 1.4), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated to form a 0.2 μm thin film. Next, after heat-treating this coating film on a hot plate, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the PZT thin film and stamped to a depth of about 0.1 μm. A two-dimensional periodic structure having a depression of 2 μm was formed. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. Next, the above 2
On a thin film having a two-dimensional PZT periodic structure, a polyimide coating solution is spin-coated at about 0.2 μm, heat-treated on a hot plate, and the above-described mold having a 0.8 μm periodic structure is pressed against the above polyimide thin film and stamped. Then, a two-dimensional periodic structure having a depression of about 0.2 μm was formed. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. The three-dimensional uniform periodic structure was produced by repeating the above-mentioned thin film formation and engraving steps 10 times each.

Further, the three-dimensional periodic structure including the non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the first and second embodiments. First, a PZT thin film of about 0.2 μm was formed on the ten-period three-dimensional uniform periodic structure manufactured as described above by the method described above.
A mold having a non-uniform structure as shown in FIG. 20 was pressed against the center of the 0.8 μm periodic structure used in 4 and stamped, and then heat-treated on a hot plate to be solidified. Next, a uniform periodic structure of 0.2 μm of polyimide and 0.2 μm of PZT for 10 periods is formed on the non-uniform structure of PZT in the same manner as in the case where the above-mentioned uniform periodic structure is formed. did.

[Embodiment 18] A three-dimensional photonic crystal was manufactured by the manufacturing method based on the fourth embodiment.

Here, as the material having the first refractive index, lead zirconate titanate (refractive index: about 2.6), which is an oxide composite material containing titanium, and polyimide as the material having the second refractive index. (With a refractive index of about 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform portion were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate, spin-coated, and then heat-treated on a hot plate to about 0.1 μm.
A 2 μm PZT thin film was formed. Next, an appropriate amount of a polyimide coating solution was dropped on the PZT thin film, spin-coated, and heat-treated on a hot plate to form a polyimide thin film of about 0.2 μm. This is repeated 10 times and P for 10 cycles
An alternate layered film of ZT and polyimide was formed. afterwards,
A mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the above-described alternately laminated film and stamped,
Heating was performed on a hot plate to solidify the alternately laminated film. Thus, a three-dimensional uniform periodic structure was formed.

Further, a three-dimensional periodic structure including a non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the third and fourth embodiments. First, about 0.2 μm was formed on the three-dimensional uniform periodic structure prepared above by the method described above.
m PZT thin film was formed and 0.8 μm used in Example 14.
A mold having a non-uniform structure as shown in FIG. 20 was pressed against the center of the periodic structure and stamped, and then heat-treated on a hot plate to be solidified. Next, in the same manner as in the case where the above-mentioned uniform periodic structure was formed on the above-mentioned non-uniform structure of PZT, 1 μm of 0.2 μm of polyimide and 0.2 μm of PZT were formed.
A zero-period uniform periodic structure was formed.

[Embodiment 19] In this embodiment, as a material having a first refractive index, PZT (refractive index: about 2.6), which is an oxide composite material containing titanium, and a material having a second refractive index Using polyimide (refractive index about 1.5) as the fifth
A three-dimensional periodic structure including a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part is manufactured based on the embodiment.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated to form a 0.2 μm thin film. Next, after heat-treating this coating film on a hot plate, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 14 was pressed against the PZT thin film and stamped to a depth of about 0.1 μm. A two-dimensional periodic structure having a depression of 2 μm was formed. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. Next, on the thin film having the two-dimensional PZT periodic structure, a polyimide coating solution is spin-coated at about 0.2 μm and heat-treated on a hot plate to form a mold having a column pattern around the 0.8 μm periodic structure. Was pressed against the above-mentioned polyimide thin film and stamped to form a two-dimensional periodic structure having a depression of about 0.2 μm.
Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. After the above-mentioned thin film formation and engraving are repeated 10 times, the polyimide layer is removed by immersing the substrate in an organic polymer etchant, and PZT
Was formed.

Further, the three-dimensional periodic structure including the non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the third and fourth embodiments. First, a PZT thin film of about 0.2 μm was formed on a 10-period uniform periodic structure of 0.2 μm PZT and 0.2 μm polyimide produced as described above by the method described above, and used in Example 3. A mold having a non-uniform structure as shown in FIG. 20 was pressed against the center of the 0.8 μm periodic structure and stamped, followed by heat treatment with a hot plate to solidify. Next, 0.2 μm of polyimide and 0.2 μm of PZT were formed on the non-uniform structure of PZT in the same manner as when the above-mentioned uniform periodic structure was formed.
After laminating a 10-period uniform periodic structure, the substrate was immersed in an organic polymer etchant to remove the polyimide layer, thereby forming a PZT three-dimensional periodic structure.

[Example 20] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the sixth embodiment.

Here, PZT (a refractive index of about 2.6), which is an oxide composite material containing titanium, is used as a material having a first refractive index, and polyimide (a refractive index of about 2.6) is used as a material having a second refractive index. 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including an uneven part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated to form a 0.2 μm thin film. Next, after heat-treating this coating film on a hot plate, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the PZT thin film and stamped to a depth of about 0.1 μm. A two-dimensional periodic structure having a depression of 2 μm was formed.
Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. Next, the two-dimensional PZ
On a thin film having a T-periodic structure, a polyimide coating solution is spin-coated about 0.2 μm, heat-treated on a hot plate, and the above-mentioned mold having a 0.8 μm periodic structure is pressed against the above-mentioned polyimide thin film and stamped. 2 with a depression of 0.2μm
A two-dimensional periodic structure was formed. After that, the pattern-exposed portions were removed by irradiating ultraviolet rays using a photomask to remove the pattern-exposed portions, and then heated with a hot plate to solidify the thin film having the two-dimensional periodic structure. After each of the above-described thin film formation, stamping and ultraviolet irradiation steps was repeated 10 times, the substrate was immersed in an organic polymer etchant to remove the polyimide layer and form a three-dimensional uniform periodic structure of PZT.

Further, the three-dimensional periodic structure including the non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the third and fourth embodiments. First, a PZT thin film of 0.2 μm produced as described above was formed, and a mold having a non-uniform structure as shown in FIG. 20 was pressed against the center of the 0.8 μm periodic structure used in Example 4. After engraving, it was heat-treated on a hot plate and solidified. Next, 0.2 μm of polyimide and 0.2 μm of PZT were formed on the non-uniform structure of PZT in the same manner as when the above-mentioned uniform periodic structure was produced.
After laminating a 10-period uniform periodic structure with 2 μm of PZT, the substrate was immersed in an organic polymer etchant to remove the polyimide layer, thereby forming a three-dimensional periodic structure of PZT.

[Example 21] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the seventh embodiment.

Here, PZT (refractive index: about 2.6), which is an oxide composite material containing titanium, is used as the material having the first refractive index, and polyimide (refractive index: about 2.6) is used as the material having the second refractive index. 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including an uneven part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate, spin-coated, and then heat-treated on a hot plate to about 0.1 μm.
A 2 μm PZT thin film was formed. Next, an appropriate amount of a polyimide coating solution was dropped on the PZT thin film, spin-coated, and heat-treated on a hot plate to form a polyimide thin film of about 0.2 μm. This is repeated 10 times and P for 10 cycles
An alternate layered film of ZT and polyimide was formed. Next,
A mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the above-described alternately laminated film and stamped. However, for the uppermost polyimide film, 0.2μ
Since m had insufficient dry etching resistance, it was stamped and solidified and then applied again to a thickness of 5 μm. Next, the above alternately laminated film was irradiated with ultraviolet rays using a photomask and developed to remove the pattern exposed portions, and then solidified by heating on a hot plate. Then, after forming a pattern, a PZT liquid was buried in the etched portion and solidified by heating. Finally, the polyimide layer was removed by immersing the substrate in an organic polymer etchant to form a three-dimensional periodic structure of PZT.

Further, a three-dimensional periodic structure including a non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the first and second embodiments. First, about 0.2 μm is formed on the three-dimensional uniform periodic structure prepared above by the above-described method.
m PZT thin film was formed and 0.8 μm used in Example 14.
A mold having a non-uniform structure as shown in FIG. 20 was pressed against the center of the periodic structure and stamped, and then heat-treated on a hot plate to be solidified. Next, on the above-mentioned non-uniform structure of PZT, in the same manner as when the above-mentioned uniform periodic structure was produced,
9. 0.2 μm of polyimide and 0.2 μm of PZT
An alternately laminated film was formed for five cycles (so that the polyimide was at the top) and stamped to form a uniform periodic structure. However,
The uppermost polyimide film has a thickness that can withstand dry etching. Next, the alternately laminated film was irradiated with ultraviolet rays using a photomask and developed to remove the pattern exposed portions, and then solidified by heating on a hot plate. Then, using the patterned polyimide thin film as a mask, the alternately laminated structure was etched by dry etching, and a PZT solution was buried in the etched portion and solidified by heating. Finally, the substrate was immersed in an organic polymer etching solution to remove the polyimide layer, thereby forming a three-dimensional periodic structure of PZT.

Example 22 A three-dimensional photonic crystal was manufactured by a manufacturing method based on the fifth embodiment.

Here, PZT (refractive index: about 2.6), which is an oxide composite material containing titanium, is used as the material having the first refractive index, and photoresist (refractive index) is used as the material having the second refractive index. About 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated to form a 0.2 μm thin film. Next, after heat-treating this coating film on a hot plate, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 14 was pressed against the PZT thin film and stamped to a depth of about 0. A two-dimensional periodic structure having a depression of 0.2 μm was produced. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. Next, a photoresist coating solution is spin-coated about 0.2 μm on the thin film having the two-dimensional PZT periodic structure, and heat-treated on a hot plate to form a column pattern around the 0.8 μm periodic structure. The mold was pressed against the above photoresist thin film and stamped to form a two-dimensional periodic structure having a depression of about 0.2 μm. Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. The above thin film formation,
After the stamping was repeated 10 times, the photoresist layer was removed by immersing the substrate in an organic polymer etchant to form a three-dimensional uniform periodic structure of PZT.

Further, the three-dimensional periodic structure including the non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the first and second embodiments. First, on a uniform structure of 0.2 μm of PZT and 0.2 μm of photoresist prepared as described above having a period of 10 periods, a thickness of about 0.2 μm was obtained by the method described above. A PZT thin film of 12 μm is formed, a mold having a non-uniform structure as shown in FIG. 20 is pressed and stamped on the center of the 0.8 μm periodic structure used in Example 1, and then solidified by heat treatment on a hot plate. did. Next, 0.2 μm of polyimide and 0.2 μm of PZT were formed on the non-uniform structure of PZT in the same manner as when the above-mentioned uniform periodic structure was formed.
After laminating a 10-period uniform periodic structure, the photoresist layer was removed by immersing the substrate in an organic polymer etchant to form a PZT three-dimensional periodic structure.

[Example 23] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the fifth embodiment.

Here, PZT (refractive index: about 2.6), which is an oxide composite material containing titanium, is used as the material having the first refractive index, and photoresist (refractive index) is used as the material having the second refractive index. About 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, an appropriate amount of a PZT solution was dropped on a silicon substrate and spin-coated to form a 0.2 μm thin film. Next, after heat-treating this coating film on a hot plate, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the PZT thin film and stamped to a depth of about 0.2 μm. A two-dimensional periodic structure having a depression was formed.
Thereafter, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. Next, the two-dimensional PZT
A photoresist coating solution (manufactured by Tokyo Ohka Kogyo Co., Ltd.) is spin-coated about 0.2 μm on the thin film having a periodic structure, and heat-treated on a hot plate. To form a two-dimensional periodic structure having a depression of about 0.2 μm.
Then, after irradiating with ultraviolet rays using a photomask and developing to remove the pattern exposed portion, the thin film having the two-dimensional periodic structure was solidified by heating on a hot plate. After repeating the above-described thin film formation, engraving, and ultraviolet irradiation steps 10 times each, the photoresist layer was removed by immersing the substrate in an organic polymer etchant to form a three-dimensional uniform periodic structure of PZT.

Further, the three-dimensional periodic structure including the non-uniform portion was manufactured as follows in accordance with the manufacturing processes of the first and second embodiments. First, a PZT thin film of about 0.2 μm was formed on the 10-period uniform periodic structure of 0.2 μm PZT and 0.2 μm photoresist prepared as described above by the method described above. A mold having an inhomogeneous structure as shown in FIG. 20 was pressed against the center of the used 0.8 μm periodic structure and stamped, followed by heat treatment with a hot plate to solidify. Next, 0.2 μm of polyimide and 0.2 μm of PZT were formed on the non-uniform structure of PZT in the same manner as in the case where the uniform periodic structure was formed.
After laminating a uniform periodic structure for 10 cycles with T, the photoresist layer was removed by immersing the substrate in an etchant for organic polymer to form a three-dimensional periodic structure of PZT.

[Example 24] A three-dimensional photonic crystal was manufactured by a manufacturing method based on the seventh embodiment.

Here, PZT (refractive index: about 2.6), which is an oxide composite material containing titanium, is used as the material having the first refractive index, and photoresist (refractive index) is used as the material having the second refractive index. About 1.5), a three-dimensional uniform periodic structure and a three-dimensional periodic structure including a non-uniform part were produced.

First, a PZT solution is applied and dropped on a silicon substrate, and is spin-coated.
A 2 μm PZT thin film was formed. On the PZT thin film,
An appropriate amount of a photoresist coating solution was dropped and spin-coated, and then heat-treated on a hot plate to form a photoresist thin film of about 0.2 μm. This is repeated 10 times and P for 10 cycles
An alternate layered film of ZT and photoresist was formed. Next, a mold having a uniform periodic structure of 0.8 μm similar to that used in Example 1 was pressed against the above-mentioned alternately laminated film and stamped. Next, the alternately laminated film was irradiated with ultraviolet rays using a photomask and developed to remove the pattern exposed portions, and then solidified by heating on a hot plate. However, in order to impart dry etching resistance to the uppermost photoresist film, after being stamped and solidified, it was applied again and thickened. afterwards,
Using the patterned photoresist thin film as a mask, the alternately laminated structure was etched by dry etching, and then a PZT solution was embedded in the etched portion to be solidified by heating. Finally, the substrate was immersed in an organic polymer etchant to remove the difference in the photoresist, thereby forming a three-dimensional periodic structure of PZT.

Further, the three-dimensional periodic structure including the non-uniform portions was manufactured as follows in accordance with the manufacturing processes of the first and second embodiments. First, about 0.2 μm is formed on the three-dimensional periodic structure prepared above by the method described above.
The PZT thin film was formed and stamped with a mold having a non-uniform structure as shown in FIG. 20 at the center of the periodic structure used in Example 1, followed by heat treatment with a hot plate to solidify. Next, on the non-uniform structure of the PZT, a 10.5 period of 0.2 μm of photoresist and 0.2 μm of PZT for a period of 10.5 (The uppermost layer) was formed and stamped to form a uniform periodic structure. However,
The uppermost photoresist film was made thick to withstand dry etching. Next, the alternately laminated film was irradiated with ultraviolet rays using a photomask and developed to remove the pattern exposed portions, and then solidified by heating on a hot plate. afterwards,
Using the patterned polyimide thin film as a mask, the layered structure was etched by dry etching, and PZ droplets were buried in the etched portions and fixed by heating. Finally, the substrate was immersed in an organic polymer etching solution to remove the polyimide layer, thereby forming a three-dimensional periodic structure of PZT.

In this embodiment, the material having the first refractive index has a high refractive index, the material having the second refractive index has a low refractive index, and the material having the first refractive index is Although alternately stacked as the first layer, a material having the second refractive index can be used as the first layer depending on the situation. Further, the present invention includes a case where a soft film such as an organic film is introduced between the substrate and the first layer as needed to facilitate engraving. Further, the heat treatment conditions before and after the marking are not limited to the present embodiment alone, but can be changed or added as appropriate from the viewpoint of the ease of marking and improvement of the film quality. Further, in this embodiment, the heat treatment is performed on a hot plate. However, an infrared lamp heating furnace or a hot plate with an ultraviolet irradiation mechanism as used in a semiconductor process can be used. In the former case, high-speed processing is possible, and in the latter case, low-temperature processing is possible. Furthermore, in this embodiment, the heat treatment before and after the marking and the marking step were performed in an indoor atmosphere, and the marking step was performed at room temperature.From the viewpoint of improving the quality of the photonic crystal, the former was performed in an atmosphere such as nitrogen or oxygen. The latter can be carried out while heating.

[0176]

As described above, in the method for producing a two-dimensional photonic crystal according to the present invention, the production process of the two-dimensional photonic crystal is simplified as compared with the conventional method.
In addition, it is possible to easily perform non-uniform portions in the crystal required for device fabrication, and as a result, it is possible to realize a high-performance optical device such as an ultra-small optical circuit or a laser resonator. Further, the method of manufacturing a three-dimensional photonic crystal according to the present invention simplifies the manufacturing process of the three-dimensional photonic crystal as compared with a conventional one, and introduces an uneven portion into the crystal necessary for device manufacturing. Can be easily performed, and as a result, a high-performance optical device such as an ultra-small optical circuit or an ultra-low threshold laser can be realized.

[Brief description of the drawings]

FIGS. 1A to 1D are views for explaining an example of a method for manufacturing a two-dimensional photonic crystal based on the present invention, and FIGS.

FIGS. 2A to 2C are schematic cross-sectional views for explaining an example of a method for manufacturing a two-dimensional photonic crystal according to the present invention. FIGS.

FIG. 3 is a schematic cross-sectional view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

FIG. 4 is a schematic cross-sectional view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

FIG. 5 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

6 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIG. 7 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

8 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIG. 9 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

10 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIG. 11 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

12 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIG. 13 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

14 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIG. 15 is a perspective view of an example of a structure having a two-dimensional microstructure applied to a method for manufacturing a two-dimensional photonic crystal according to the present invention.

16 is a perspective view showing an example of a two-dimensional photonic crystal having a two-dimensional periodic structure formed using the structure shown in FIG.

FIGS. 17A to 17D are views for explaining an example of a method for manufacturing a three-dimensional photonic crystal according to the present invention, and FIGS. 17A to 17D are schematic cross-sectional views for explaining each step.

FIG. 18 is a perspective view of a mold used in the method for producing a three-dimensional photonic crystal according to the present invention.

19 is a perspective view showing an example of a three-dimensional photonic crystal having a three-dimensional periodic structure formed using the mold shown in FIG.

FIG. 20 is a perspective view of a mold used in the method for producing a three-dimensional photonic crystal according to the present invention.

21 is a perspective view showing an example of a three-dimensional photonic crystal having a three-dimensional periodic structure formed using the mold shown in FIG.

FIG. 22 is a perspective view of a mold used in the method for producing a three-dimensional photonic crystal according to the present invention.

FIG. 23 is a perspective view showing an example of a three-dimensional periodic structure formed using the mold shown in FIG.

24 (a) and 24 (b) are schematic cross-sectional views for explaining each step of the method for manufacturing a three-dimensional photonic crystal according to the second embodiment of the present invention. .

FIGS. 25A to 25F are diagrams for explaining a third example of a method for manufacturing a three-dimensional photonic crystal according to the present invention, and FIGS. 25A to 25F are schematic cross-sectional views for explaining each process. .

FIG. 26 is a perspective view of a mold used in the method for producing a three-dimensional photonic crystal according to the present invention.

FIG. 27 is a perspective view showing an example of a three-dimensional microstructure formed by a method for manufacturing a three-dimensional photonic crystal according to the present invention.

FIG. 28 is a perspective view showing an example of a three-dimensional microstructure formed by a method for producing a three-dimensional photonic crystal according to the present invention.

FIG. 29 is a perspective view showing an example of a three-dimensional microstructure formed by a method for producing a three-dimensional photonic crystal according to the present invention.

FIGS. 30A to 30F are views for explaining a fourth example of the method for manufacturing a three-dimensional photonic crystal according to the present invention, and FIGS. 30A to 30F are schematic cross-sectional views for explaining each step. .

FIGS. 31A to 31D are views for explaining a fourth example of the method for manufacturing a three-dimensional photonic crystal according to the present invention, and FIGS. .

32 (a) to (f) are schematic cross-sectional views for explaining each step of the method for manufacturing a three-dimensional photonic crystal according to the sixth embodiment of the present invention. .

FIG. 33 is a perspective view of a mold applied by the method shown in FIG. 32;

FIG. 34 is a perspective view showing a three-dimensional laminate structure created by the method shown in FIG. 32;

FIGS. 35 (a) to 35 (e) are schematic cross-sectional views illustrating each step of a method for manufacturing a three-dimensional photonic crystal according to a sixth embodiment of the present invention. FIGS. .

FIG. 36 is a perspective view of a mold applied by the method shown in FIG. 35;

FIG. 37 is a perspective view showing a three-dimensional laminate structure created by the method shown in FIG. 35;

[Explanation of symbols]

 Reference Signs List 1 substrate 2 thin film made of material having first refractive index 3 thin film made of material having second refractive index 4 type 5 type 6 type 7 photomask 8 ultraviolet ray 9 resist 11 structure having two-dimensional microstructure (substrate 12) Material having a first refractive index 13 Substrate 14 Structure (substrate) having a two-dimensional fine structure 15 Structure (substrate) having a two-dimensional fine structure 16 Structure (substrate) having a two-dimensional fine structure 17 2 Structure having two-dimensional fine structure (substrate) 18 Structure having two-dimensional fine structure (substrate) 19 Structure having two-dimensional fine structure (substrate)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiaki Tamamura 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Hiroshi Nozawa 3-192-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo No. F-term in Nippon Telegraph and Telephone Corporation (reference) 2H047 KA00 PA02 PA21 PA24 QA01 QA04 QA05 TA00 TA43

Claims (11)

[Claims] 1. A method for producing a photonic crystal having a laminated structure in which thin films are laminated on a substrate, comprising the steps of: producing a periodic two-dimensionally arranged fine structure on the substrate; Forming a thin film made of a material having the following on the microstructure; and pushing the thin film into the microstructure. A method for producing a two-dimensional photonic crystal, comprising: 2. A method for producing a photonic crystal having a laminate structure in which a thin film is laminated on a substrate, comprising: forming a thin film made of a material having a refractive index n1 on a first substrate; Forming a periodic two-dimensionally arranged fine structure on a second substrate; and pressing the fine structure on the second substrate into the thin film on the first substrate. A method for producing a two-dimensional photonic crystal. 3. The method for manufacturing a two-dimensional photonic crystal according to claim 1, wherein the substrate uses a material having a refractive index lower than that of the thin film. 4. The microstructure according to claim 1, wherein the microstructure has a non-periodic part in a part of a periodic two-dimensional arrangement.
4. The method for producing a two-dimensional photonic crystal according to any one of items 3 to 3. 5. The method for manufacturing a two-dimensional photonic crystal according to claim 1, further comprising a post-process of removing the substrate. 6. A method for producing a three-dimensional photonic crystal having a laminated structure in which a plurality of thin films are laminated on a substrate, wherein a first thin film made of a first material having a refractive index n1 is formed. Performing a step of pressing a mold having a predetermined microstructure on the first thin film and engraving the same; and forming a second material having a refractive index n2 on the first thin film on which the engraving is performed. Forming a laminate structure by repeating at least once a step of laminating a second thin film, and a step of stamping the second thin film with a mold having a predetermined fine structure. A method for producing a three-dimensional photonic crystal. 7. The method for producing a three-dimensional photonic crystal according to claim 6, further comprising a step of removing one of the first thin film and the second thin film. 8. A method for manufacturing a three-dimensional photonic crystal having a stacked structure in which a plurality of thin films are stacked on a substrate, wherein a first thin film made of a first material having a refractive index n1 is formed. The step of laminating a second thin film made of a second material having a refractive index n2 on the first thin film is repeated at least once, whereby the first thin film and the second thin film are separated. A three-dimensional photonic, comprising: a step of forming an alternately stacked alternately laminated structure; and a step of pressing a mold having a predetermined fine structure against the alternately stacked structure to perform engraving. How to make a crystal. 9. The method for producing a three-dimensional photonic crystal according to claim 8, further comprising a step of removing one of the first thin film and the second thin film. 10. The method for producing a three-dimensional photonic crystal according to claim 6, wherein the predetermined fine structure uses a fine structure having a periodic two-dimensional arrangement. 11. The three-dimensional photonic according to claim 6, wherein the predetermined fine structure has a non-periodic part in a part of a periodic two-dimensional arrangement. How to make a crystal.