Porous plate, and method for manufacturing a porous plate

Abstract

The present invention provides a porous plate with improved mechanical strength, and a method for manufacturing such a porous plate. [Solution] The porous plate 1 comprises a substrate 2 having a porous portion 21 having a main surface 21a, the porous portion 21 having a plurality of first holes 24 opening into the main surface 21a and a plurality of second holes 25 opening into the main surface 21a and each having a width greater than the width of each of the plurality of first holes 24, and a filling member 3 filled into the plurality of first holes 24.

Description

Technical Field

[0001] The present invention relates to a porous plate and a method for manufacturing the porous plate.

Background Art

[0002] Patent Document 1 discloses an anodic oxidized porous alumina in which a plurality of pores are formed as an example of a porous plate. In the anodic oxidized porous alumina described in Patent Document 1, a plurality of holes each having a diameter larger than the diameter of the pores formed by anodic oxidation are formed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The porous plate as described above can be used for various applications such as an X-ray grid or a well plate in an X-ray imaging (detection) device. Therefore, the porous plate is required to have mechanical strength according to the application.

[0005] An object of the present invention is to provide a porous plate with improved mechanical strength and a method for manufacturing such a porous plate.

Means for Solving the Problems

[0006] The porous plate of the present invention is [1] "a porous portion having a first main surface, a substrate having the porous portion in which a plurality of first holes opening in the first main surface and a plurality of second holes opening in the first main surface and each having a width larger than the width of each of the plurality of first holes are formed, and a filling member filled in the plurality of first holes".

[0007] In the porous plate described above, multiple second holes are formed in the porous portion. This allows the porous plate to be used for various applications, such as X-ray grids and well plates in X-ray imaging devices. Furthermore, in the porous plate described above, a filling material is filled into the multiple first holes formed in the porous portion. This suppresses warping of the porous portion and improves the robustness of the porous plate. Thus, the mechanical strength of the porous plate can be improved.

[0008] The porous plate of the present invention may also be [2] "the porous plate described in [1] above, wherein the porous portion includes an anodic oxide film of valve metal or silicon." In this case, a plurality of first holes can be composed of pores in the anodic oxide film. Therefore, a decrease in the mechanical strength of the porous plate can be suppressed.

[0009] The porous plate of the present invention may also be [3] "the porous plate according to [1] or [2] above, wherein the width of each of the plurality of first holes is 10 nm or more and 1000 nm or less." By having a width of 10 nm or more for the first holes, a space for filling with a filler material can be secured inside the first holes. Furthermore, by having a width of 1000 nm or less for the first holes, a decrease in the strength of the porous plate can be suppressed.

[0010] The porous plate of the present invention may also be [4] "a porous plate according to any one of [1] to [3] above, wherein the porous portion has a second main surface opposite to the first main surface, and each of the plurality of second holes is a through hole opening to the first main surface and the second main surface." In this case, the porous plate can be used in applications where through holes are preferred, for example, as an X-ray grid in an X-ray imaging apparatus.

[0011] The porous plate of the present invention may also be [5] "the porous plate according to any one of [1] to [3] above, wherein the substrate further has a support portion located on the opposite side of the first main surface from the porous portion and supporting the porous portion, and each of the plurality of second holes is a non-through hole having the surface of the support portion on the porous portion side as its bottom surface." In this case, the porous plate can be used in applications where non-through holes are preferable, such as a well plate. Furthermore, the presence of a support portion in the substrate can further improve the mechanical strength of the porous plate.

[0012] The porous plate of the present invention may also be [6] "the porous plate described in [5] above, wherein the support portion is formed integrally with the porous portion." In this case, the structure of the porous plate can be made simpler.

[0013] The porous plate of the present invention may also be [7] "the porous plate according to [5] above, wherein the support portion is formed separately from the porous portion." In this case, the design freedom of the porous plate is improved. For example, the support portion can be formed from a different material than the material of the porous portion, and a design can be realized that meets the performance requirements for each application in which the porous plate is used.

[0014] The porous plate of the present invention may also be [8] "a porous plate according to any one of [1] to [7] above, wherein the porous portion comprises a first portion in which the plurality of second holes are formed, and a second portion located along the outer edge of the porous portion when viewed from the thickness direction of the substrate and in which the plurality of second holes are not formed." In this case, the mechanical strength of the porous plate can be further improved by having the second portion in which the second holes are not formed located along the outer edge of the porous portion.

[0015] The porous plate of the present invention may also be [9] "a porous plate according to any one of [1] to [8] above, wherein the filling member is formed of an oxide, a metal compound, or a resin." In this case, the mechanical strength of the porous plate can be improved more reliably.

[0016] The porous plate of the present invention may also be

[10] "a porous plate according to any one of [1] to [9] above, wherein the substrate is curved." In this case, for example, when the porous plate is used as an X-ray grid in an X-ray imaging device, diffracted X-rays emitted radially from the sample can be efficiently passed through.

[0017] The present invention provides a method for manufacturing a porous plate, comprising:

[11] "the steps of: preparing a substrate having a main surface; forming a plurality of first holes in the substrate that open to the main surface; forming a plurality of second holes in the substrate that open to the main surface and each having a width greater than the width of each of the plurality of first holes; and filling the plurality of first holes with a filling material." According to this method for manufacturing a porous plate, a porous plate with improved mechanical strength can be manufactured for the reasons described above.

[0018] The method for manufacturing a porous plate of the present invention may also be

[12] "the method for manufacturing a porous plate according to

[11] above, wherein in the step of preparing the substrate, the substrate is made of valve metal or silicon, and in the step of forming the plurality of first holes, the plurality of first holes are formed by anodizing the substrate." In this case, the plurality of first holes can be easily formed.

[0019] The method for manufacturing a porous plate of the present invention may also be

[13] "the method for manufacturing a porous plate according to

[11] or

[12] above, wherein in the step of filling the filling member, the filling member is filled into the plurality of first holes by atomic layer deposition." In this case, the filling member can be reliably filled into the plurality of first holes.

[0020] The manufacturing method of the porous plate of the present invention may be "

[14] In the step of filling the filling member, the filling member is filled into the plurality of first holes by the dip coating method, and the manufacturing method of the porous plate described in

[11] or

[12] above". In this case, the filling member can be reliably filled into the plurality of first holes.

[0021] The manufacturing method of the porous plate of the present invention may be "

[15] In the step of forming the plurality of second holes, the plurality of second holes are formed by removing a part of the substrate by etching, and the manufacturing method of the porous plate described in any one of

[11] to

[14] above". In this case, the shape, arrangement, pitch, etc. of the plurality of second holes can be freely designed, and a porous plate suitable for the application can be manufactured.

Advantages of the Invention

[0022] According to the present invention, it is possible to provide a porous plate with improved mechanical strength and a manufacturing method of such a porous plate.

Brief Description of the Drawings

[0023] [Figure 1] It is a diagram showing the overall configuration of an X-ray imaging apparatus to which the porous plate is applied. [Figure 2] It is a plan view showing the porous plate according to the first embodiment. [Figure 3] It is an enlarged cross-sectional view of the porous plate shown in FIG. 2. [Figure 4] It is an enlarged view of the region A1 shown in FIG. 2. [Figure 5] It is an enlarged view of the region A2 shown in FIG. 2. [Figure 6] It is a diagram for explaining the manufacturing method of the porous plate shown in FIG. 2. [Figure 7] It is a diagram for explaining the manufacturing method of the porous plate shown in FIG. 2. [Figure 8] It is a diagram for explaining the manufacturing method of the porous plate shown in FIG. 2. [Figure 9]Figure 2 is a diagram illustrating the manufacturing method of the porous plate shown. [Figure 10] Figure 2 is a diagram illustrating the manufacturing method of the porous plate shown. [Figure 11] This is an enlarged cross-sectional view of a porous plate according to the second embodiment. [Figure 12] This is an enlarged cross-sectional view of a porous plate according to the third embodiment. [Figure 13] This is an enlarged cross-sectional view of a porous plate according to a modified example. [Modes for carrying out the invention]

[0024] An example of the present invention will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are omitted. [First Embodiment] [X-ray imaging device]

[0025] Referring to Figure 1, the configuration of the X-ray imaging apparatus 100 to which the porous plate 1 according to this embodiment is applied will be described. In this example, the porous plate 1 is used as an X-ray grid in the X-ray imaging apparatus 100. An X-ray grid allows X-rays to pass in a specific direction and blocks X-rays in other directions. The apparatus to which the porous plate 1 is applied and the application of the porous plate 1 are not limited. The porous plate 1 may be used as an X-ray slit used in XRD (X-ray diffraction) or as an X-ray focusing capillary.

[0026] The X-ray imaging apparatus 100 comprises an X-ray source 101 that emits X-rays XL, a Talbot interferometer 102 that is irradiated by the X-rays XL emitted from the X-ray source 101, and an X-ray imaging unit 103 that captures the X-ray image XM emitted from the Talbot interferometer 102. The sample F to be imaged is placed between the X-ray source 101 and the Talbot interferometer 102. The Talbot interferometer 102 has a porous plate 1 as an X-ray grid. [Composition of a porous plate]

[0027] The configuration of the porous plate 1 will be described with reference to Figures 2 to 5. The porous plate 1 comprises a substrate 2 and a filling member 3. In Figures 4 and 5, the filling member 3 is omitted from the illustration for convenience of explanation. Hereinafter, the thickness direction of the substrate 2 will be defined as the Z-axis direction, one direction intersecting the Z-axis direction will be defined as the X-axis direction, and the direction intersecting the Z-axis direction and the X-axis direction will be defined as the Y-axis direction. In this embodiment, the X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other.

[0028] The substrate 2 has a porous portion 21. The porous portion 21 is a plate-shaped member having thickness in the Z-axis direction. In this example, the porous portion 21 is formed in a circular plate shape. The porous portion 21 has a main surface (first main surface) 21a and a main surface (second main surface) 21b. The main surfaces 21a and 21b extend perpendicularly in the Z-axis direction. The main surface 21b is located on the opposite side of the main surface 21a in the Z-axis direction.

[0029] Multiple first holes 24 and multiple second holes 25 are formed in the porous portion 21. In the following description, the multiple first holes 24 are described as holes, but this is for the sake of simplicity, and in the porous plate 1, the first holes 24 are filled by the filling material 3 and do not exist as holes. Each of the multiple first holes 24 extends along the Z-axis direction. Specifically, the axis of each of the multiple first holes 24 extends along the thickness direction (Z-axis direction) of the substrate 2 and is substantially parallel to each other. The axes of each of the multiple first holes 24 do not intersect each other. Each of the multiple first holes 24 penetrates the porous portion 21 from the main surface 21a to the main surface 21b. In other words, each of the multiple first holes 24 is a through hole that opens to the main surface 21a and the main surface 21b.

[0030] The shape of the first hole 24 when viewed from the Z-axis direction is, for example, circular. The shape of the first hole 24 does not have to be a perfect circle; it may be approximately circular. When viewed from the Z-axis direction, the width of each of the multiple first holes 24 is, for example, between 10 nm and 1000 nm. The width of the first hole 24 refers to the diameter of the first hole 24 when viewed from the thickness direction of the substrate 2 if the shape of the first hole 24 is circular, and if the shape is other than circular, it refers to the diameter (effective diameter) of the largest virtual cylinder that fits into the first hole 24.

[0031] The width of the first hole 24 is obtained as follows. First, images of the main surface 21a and the main surface 21b of the porous portion 21 are obtained. These images may be obtained, for example, using a scanning electron microscope (SEM). Next, by applying a binarization process, for example, to the obtained image of the main surface 21a, multiple pixel groups corresponding to multiple first apertures (apertures of the first hole 24 on the main surface 21a side) are extracted, and the diameter of a circle having the average area of ​​the first aperture is obtained based on the size of each pixel. Similarly, by applying a binarization process, for example, to the obtained image of the main surface 21b, multiple pixel groups corresponding to multiple second apertures (apertures of the first hole 24 on the main surface 21b side) are extracted, and the diameter of a circle having the average area of ​​the second aperture is obtained based on the size of each pixel. Then, the average value of the diameter of the circle obtained for the main surface 21a and the diameter of the circle obtained for the main surface 21b is obtained as the width of the first hole 24. The sizes of the multiple first holes 24 may be different from each other, and the multiple first holes 24 may be partially connected to each other.

[0032] In this embodiment, each of the multiple first holes 24 is formed uniformly (with a substantially uniform distribution) in the substrate 2. The multiple first holes 24 are arranged regularly when viewed from the Z-axis direction. In this example, the multiple first holes 24 are arranged in a triangular grid. The pitch (spacing) of adjacent first holes 24 is obtained as follows. First, as described above, images of the main surface 21a and the main surface 21b are obtained. Next, multiple pixel groups corresponding to the multiple first apertures are extracted, and the average distance between the center positions of adjacent first apertures is obtained. Similarly, multiple pixel groups corresponding to the multiple second apertures are extracted, and the average distance between the center positions of adjacent second apertures is obtained. Then, the average value of the average distance obtained for the main surface 21a and the average distance obtained for the main surface 21b is obtained as the pitch between adjacent first holes 24.

[0033] Each of the multiple second holes 25 extends along the Z-axis direction. Specifically, the axis of each of the multiple second holes 25 extends along the thickness direction of the substrate 2 and is substantially parallel to each other. The axes of each of the multiple second holes 25 do not intersect each other. Each of the multiple second holes 25 penetrates the porous portion 21 from the main surface 21a to the main surface 21b. In other words, each of the multiple second holes 25 is a through hole that opens into the main surface 21a and the main surface 21b.

[0034] The shape of the second hole 25 when viewed from the Z-axis direction is, for example, circular. The shape of the second hole 25 does not have to be a perfect circle; it may be approximately circular. When viewed from the Z-axis direction, the width of each of the multiple second holes 25 is, for example, greater than 1000 nm (1 μm). The width of the second hole 25 refers to the diameter of the second hole 25 when viewed from the thickness direction of the substrate 2 if the shape of the second hole 25 is circular, and if the shape is other than circular, it refers to the diameter (effective diameter) of the largest hypothetical cylinder that fits into the second hole 25.

[0035] The width of the second hole 25 is obtained in the same manner as the width of the first hole 24. First, as described above, images of the main surface 21a and the main surface 21b of the porous portion 21 are obtained. Next, by applying, for example, binarization processing to the obtained image of the main surface 21a, multiple pixel groups corresponding to multiple third apertures (apertures of the second hole 25 on the main surface 21a side) are extracted, and the diameter of the circle having the average area of ​​the third aperture is obtained based on the size of each pixel. Similarly, by applying, for example, binarization processing to the obtained image of the main surface 21b, multiple pixel groups corresponding to multiple fourth apertures (apertures of the second hole 25 on the main surface 21b side) are extracted, and the diameter of the circle having the average area of ​​the fourth aperture is obtained based on the size of each pixel. Then, the average value of the diameter of the circle obtained for the main surface 21a and the diameter of the circle obtained for the main surface 21b is obtained as the width of the second hole 25. The sizes of the multiple second holes 25 may be different from each other.

[0036] Each of the multiple second holes 25 has a width greater than each of the multiple first holes 24. The width of the second hole 25 may be 5 times or more, 10 times or more, or 20 times or more, the width of the first hole 24.

[0037] In this embodiment, each of the multiple second holes 25 is formed uniformly (with a substantially uniform distribution) in the substrate 2. The multiple second holes 25 are arranged regularly when viewed from the Z-axis direction. In this example, the multiple second holes 25 are arranged in a triangular grid. The pitch (spacing) of adjacent second holes 25 is obtained in the same way as the pitch of the first holes 24. First, as described above, images of the main surface 21a and the main surface 21b are obtained. Next, multiple pixel groups corresponding to the multiple third apertures are extracted, and the average distance between the center positions of adjacent third apertures is obtained. Similarly, multiple pixel groups corresponding to the multiple fourth apertures are extracted, and the average distance between the center positions of adjacent fourth apertures is obtained. Then, the average value of the average distance obtained for the main surface 21a and the average distance obtained for the main surface 21b is obtained as the pitch between adjacent second holes 25. The pitch of the second holes 25 is larger than the pitch of the first holes 24.

[0038] The porous portion 21 has a first portion 31 and a second portion 32, as shown in Figure 2. When viewed from the Z-axis direction, the first portion 31 is positioned to include the central part of the porous portion 21. When viewed from the Z-axis direction, the second portion 32 is positioned along the outer edge 21c of the porous portion 21. In this example, the second portion 32 has a circular frame shape that extends to surround the first portion 31. The second portion 32 is located outside the first portion 31 (away from the central part of the porous portion 21).

[0039] The first part 31 has a plurality of first holes 24 and a plurality of second holes 25. The second part 32 has a plurality of first holes 24, but no plurality of second holes 25. In other words, the second holes 25 are formed only in the first part 31 and not in the second part 32. The proportion of the internal space occupied by the first holes 24 in the second part 32 (porosity) is smaller than the proportion of the internal space occupied by the first holes 24 and second holes 25 in the first part 31 (porosity). Here, porosity refers to the proportion of the entire internal space of the first holes 24 and second holes 25, including the portion in which the filling member 3 is placed.

[0040] The porous portion 21 includes, for example, a valve metal or an anodic oxide film of silicon. In this example, the porous portion 21 itself is composed of an oxide film (alumina porous film) formed by anodizing Al (aluminum). Specifically, the porous portion 21 can be obtained by anodizing an Al substrate and peeling off the oxidized surface portion from the Al substrate. The porous portion 21 may also be formed by anodizing a valve metal other than Al, such as Ta (tantalum), Nb (niobium), Ti (titanium), Hf (hafnium), Zr (zirconium), Zn (zinc), W (tungsten), Bi (bismuth), Sb (antimony), or by anodizing Si (silicon).

[0041] The filler member 3 is filled into a plurality of first holes 24. The filler member 3 is positioned inside the first holes 24. In this example, the filler member 3 is positioned to fill the inside of the first holes 24 without any gaps. The filler member 3 is positioned across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, and the main surfaces 21a and 21b. The filler member 3 is formed to cover the entire surface of the porous portion 21. The filler member 3 is formed, for example, by atomic layer deposition (ALD) or dip coating (filled into the first holes 24).

[0042] The filler member 3 is formed of an oxide, a metal compound, or a resin. The oxide may be an inorganic oxide, a metal oxide, etc. Examples of oxides include Al2O3, SiO2, TiO2, ZnO, WO3, etc. The metal compound is a compound containing a metal element. The metal compound may be a metal, a metal oxide, etc. Examples of metal compounds include Pt, Pd, Ni, W, etc. Metal oxides are included in each of the oxides and metal compounds described above. The resin is, for example, PDMS, etc. [Method for manufacturing porous plates]

[0043] A method for manufacturing the porous plate 1 will now be described. First, a substrate 5 made of valve metal or silicon is prepared, as shown in Figure 6. In this example, an Al substrate is prepared as the substrate 5. The substrate 5 has a main surface 5a.

[0044] Next, as shown in Figure 7, a plurality of first holes 24 opening into the main surface 5a are formed in the substrate 5. Specifically, the plurality of first holes 24 are formed by anodizing the substrate 5. In this example, a porous oxide film (alumina porous film) is formed on the main surface 5a side by anodizing the substrate 5, which is an Al substrate. The substrate 5 in which the first holes 24 are formed has a portion 51 (oxide film portion) in which the first holes 24 are formed, and a portion 52 that supports portion 51. The portion 51 in which the first holes 24 are formed is an anodized portion and is made of alumina (Al2O3). In contrast, portion 52 is an unanodized portion and is made of aluminum (Al), which is the original material of the substrate 5. That is, the substrate 5 is divided into an anodized alumina portion (portion 51) and an unanodized aluminum portion (portion 52) by the anodizing treatment described above. The portion 51 (oxide film portion) where the first hole 24 is formed corresponds to the porous portion 21. In other words, through the manufacturing process of the porous plate 1, portion 51 becomes the porous portion 21.

[0045] Next, multiple second holes 25 that open into the main surface 5a are formed in the substrate 5. In this example, multiple second holes 25 are formed by removing a portion of the substrate 5 by etching. First, as shown in Figure 8, a mask 6 is placed on the main surface 5a. Multiple openings 6a are formed in the mask 6. The positions and shapes of the multiple openings 6a correspond to the positions and shapes of the multiple second holes 25 that are to be formed.

[0046] Next, as shown in Figure 9, multiple second holes 25 are formed by etching. Specifically, the portion of the substrate 5 exposed from the opening 6a of the mask 6 is removed by wet etching. This forms the second holes 25 in the portion of the substrate 5 corresponding to the opening 6a (the overlapping portion). At this time, since multiple first holes 24 having axes along the Z-axis direction have already been formed, each second hole 25 is formed so that it has an axis along the Z-axis direction (so that its depth direction is along the Z-axis direction). In this example, the second holes 25 are formed so that their depth is approximately the same as the depth of the first holes 24. The second holes 25 are formed in the portion 51 where the first holes 24 are formed.

[0047] Next, as shown in Figure 10, the mask 6 is removed from the substrate 5. Also, portion 52 is removed (peeled off) from portion 51 on the substrate 5. As a result, a porous portion 21 with the first hole 24 and the second hole 25 formed therein is obtained.

[0048] Next, the filler material 3 is filled into the multiple first holes 24. As shown in Figure 3, the filler material 3 is arranged to fill the inside of the first holes 24 without any gaps. At this time, the filler material 3 is arranged across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, the main surface 21a, and the main surface 21b. The filler material 3 is formed to cover the entire surface of the porous portion 21. As an example, the filler material 3 may be filled into the multiple first holes 24 by the ALD method or the dip coat method. By doing so, a porous plate 1 can be obtained. [Mechanism of Action and Effects]

[0049] In the porous plate 1, multiple second holes 25 are formed in the porous portion 21. This allows the porous plate 1 to be used for various applications, such as an X-ray grid in an X-ray imaging device. In addition, in the porous plate 1, a filling material 3 is filled into multiple first holes 24 formed in the porous portion 21. This suppresses warping of the porous portion 21 and improves the robustness of the porous plate 1. Therefore, the mechanical strength of the porous plate 1 can be improved.

[0050] The porous portion 21 includes an anodic oxide film of valve metal or silicon. This allows multiple first holes 24 to be formed by pores in the anodic oxide film. Therefore, a decrease in the mechanical strength of the porous plate 1 can be suppressed.

[0051] The width of each of the multiple first holes 24 is between 10 nm and 1000 nm. A width of 10 nm or more for the first holes 24 ensures that space for the filling material 3 is secured within the first holes 24. Furthermore, a width of 1000 nm or less for the first holes 24 helps to suppress a decrease in the strength of the porous plate 1.

[0052] The porous portion 21 has a main surface 21b opposite to the main surface 21a. Each of the multiple second holes 25 is a through hole opening into the main surface 21a and the main surface 21b. This allows the porous plate 1 to be used in applications where through holes are preferable, such as as an X-ray grid in an X-ray imaging device.

[0053] The porous portion 21 has a first portion 31 in which a plurality of second holes 25 are formed, and a second portion 32 which is located along the outer edge 21c of the porous portion 21 when viewed from the Z-axis direction and in which the plurality of second holes 25 are not formed. By positioning the second portion 32, in which the second holes 25 are not formed, along the outer edge 21c of the porous portion 21, the mechanical strength of the porous plate 1 can be further improved.

[0054] The filling member 3 is formed from an oxide, a metal compound, or a resin. This makes it possible to more reliably improve the mechanical strength of the porous plate 1.

[0055] According to the manufacturing method of the porous plate 1 of this embodiment, for the reasons described above, warping of the porous portion 21 is suppressed in the manufactured porous plate 1, and the robustness of the porous plate 1 is improved. Therefore, a porous plate 1 with improved mechanical strength can be manufactured.

[0056] In the step of preparing the substrate 5, a substrate 5 made of valve metal or silicon is prepared. In the step of forming the multiple first holes 24, the multiple first holes 24 are formed by anodizing the substrate 5. This makes it possible to easily form multiple first holes 24.

[0057] In the step of filling the filler material 3, the filler material 3 may be filled into the multiple first holes 24 by the ALD method. In this case, the filler material 3 can be reliably filled into the multiple first holes 24.

[0058] In the step of filling the filler member 3, the filler member 3 may be filled into the multiple first holes 24 by a dip-coating method. In this case, the filler member 3 can be reliably filled into the multiple first holes 24.

[0059] In the process of forming multiple second holes 25, a portion of the substrate 5 is removed by etching to form multiple second holes 25. This allows for free design of the shape, arrangement, pitch, etc., of the multiple second holes 25, enabling the manufacture of a porous plate 1 suitable for the application. [Second Embodiment]

[0060] Referring to Figure 11, the porous plate 1 according to the second embodiment will be described. Below, the differences from the porous plate 1 according to the first embodiment will be mainly described, and common points may be omitted from the explanation. In this embodiment, the substrate 2 further has a support portion 22 that supports the porous portion 21. The support portion 22 is located on the opposite side of the main surface 21a from the porous portion 21. The support portion 22 is formed integrally with the porous portion 21. The support portion 22 is made of, for example, valve metal or silicon. If the porous portion 21 is an anodic oxide film of a specific material (e.g., Al2O3), the support portion 22 is made of the same specific material (e.g., Al) that has not been anodized.

[0061] The support portion 22 is a plate-shaped member having thickness in the Z-axis direction. In this example, the support portion 22 is formed in the shape of a circular plate. The support portion 22 has a main surface 22a and a main surface 22b. The main surfaces 22a and 22b extend perpendicularly in the Z-axis direction. The main surface 22a is the surface of the support portion 22 on the side facing the porous portion 21. The main surface 22a is located closer to the porous portion 21 than the main surface 22b. The porous portion 21 is formed on the main surface 22a. The main surface 22b is located on the opposite side from the main surface 22a in the Z-axis direction.

[0062] In this embodiment, each of the multiple second holes 25 is a non-through hole having the main surface 22a of the support portion 22 as its bottom surface 25b. That is, the end of the second hole 25 opposite to the main surface 21a is closed by the main surface 22a.

[0063] The filling member 3 is filled into the multiple first holes 24. The filling member 3 is arranged across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, the bottom surface 25b of each second hole 25, the main surface 21a, and the main surface 21b. The filling member 3 is formed to cover the entire surface of the porous portion 21 and the main surface 22a of the support portion 22.

[0064] The porous plate 1 according to this embodiment may be used as a well plate. For example, the porous plate 1 may be used as a three-dimensional cell culture plate for culturing cell aggregates inside the second pore 25. If the support portion 22 is formed of an X-ray-transmitting material, the porous plate 1 according to this embodiment may be used, for example, as an X-ray grid (X-ray slit).

[0065] Next, the method for manufacturing the porous plate 1 according to this embodiment will be described. The method for manufacturing the porous plate 1 according to this embodiment is the same as the method for manufacturing the porous plate 1 according to the first embodiment, from the step of preparing the substrate 5 (see Figure 6) to the step of forming a plurality of second holes 25 (see Figure 9). In this embodiment, after forming a plurality of second holes 25, the mask 6 is removed to expose the main surface 5a of the substrate 5. The portion 51 (oxide film portion) of the substrate 5 in which the first holes 24 and the second holes 25 are formed corresponds to the porous portion 21, and the portion 52 that supports the portion 51 corresponds to the support portion 22. That is, after the manufacturing process of the porous plate 1, portion 51 becomes the porous portion 21, and portion 52 becomes the support portion 22.

[0066] Next, without peeling (removing) portion 52 from portion 51 on the substrate 5, the filler member 3 is filled into the plurality of first holes 24. The filler member 3 is arranged so as to fill the inside of the first holes 24 without any gaps. At this time, the filler member 3 is arranged across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, the bottom surface 25b (main surface 22a) of each second hole 25, and the main surface 21a. The filler member 3 is formed so as to cover the entire surface of the porous portion 21 and the main surface 22a of the support portion 22. As an example, the filler member 3 may be filled into the plurality of first holes 24 by the ALD method or the dip coat method. As described above, a porous plate 1 according to the second embodiment can be obtained.

[0067] The substrate 2 is located on the opposite side of the main surface 21a from the porous portion 21 and has a support portion 22 that supports the porous portion 21. Each of the multiple second holes 25 is a non-through hole with the main surface 22a of the support portion 22 as its bottom surface 25b. This allows the porous plate 1 to be used in applications where non-through holes are preferable, such as a well plate. Furthermore, the presence of the support portion 22 in the substrate 2 can further improve the mechanical strength of the porous plate 1.

[0068] The support portion 22 is formed integrally with the porous portion 21. This allows for a simpler configuration of the porous plate 1. [Third Embodiment]

[0069] Referring to Figure 12, the porous plate 1 according to the third embodiment will be described. Below, the differences from the porous plate 1 according to the first embodiment will be mainly described, and common points may be omitted from the explanation. In this embodiment, the substrate 2 further has a support portion 27 that supports the porous portion 21. The support portion 27 is located on the opposite side of the main surface 21a from the porous portion 21. The support portion 27 is formed separately from the porous portion 21. The material of the support portion 27 may be different from the material of the porous portion 21. The material of the support portion 27 may be a material with higher X-ray transmittance than the material of the porous portion 21.

[0070] The support portion 27 is a plate-shaped member having thickness in the Z-axis direction. In this example, the support portion 27 is formed in the shape of a circular plate. The support portion 27 has a main surface 27a and a main surface 27b. The main surfaces 27a and 27b extend perpendicularly in the Z-axis direction. The main surface 27a is the surface of the support portion 27 on the side facing the porous portion 21. The main surface 27a is located closer to the porous portion 21 than the main surface 27b. The porous portion 21 is formed on the main surface 27a. The porous portion 21 is fixed to the support portion 27. As an example, the porous portion 21 may be bonded to the support portion 27 by an adhesive placed between the main surface 21b and the main surface 27a. As another example, the porous portion 21 may be fused to the support portion 27 via low-melting-point glass placed between the main surface 21b and the main surface 27a. The main surface 27b is located on the opposite side from the main surface 27a in the Z-axis direction.

[0071] In this embodiment, each of the multiple second holes 25 is a non-through hole having the main surface 27a of the support portion 27 as its bottom surface 25b. That is, the end of the second hole 25 opposite to the main surface 21a is closed by the main surface 27a.

[0072] The filling member 3 is filled into a plurality of first holes 24. The filling member 3 is arranged across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, the bottom surface 25b of each second hole 25, and the main surface 21a. The filling member 3 is formed to cover the entire surface of the porous portion 21 except for the main surface 21b and the main surface 27a of the support portion 27.

[0073] The porous plate 1 according to this embodiment may be used as a well plate. For example, the porous plate 1 may be used as a three-dimensional cell culture plate for culturing cell aggregates inside the second pore 25. If the support portion 27 is formed of an X-ray-transmitting material, the porous plate 1 according to this embodiment may be used, for example, as an X-ray grid (X-ray slit).

[0074] Next, a method for manufacturing the porous plate 1 according to this embodiment will be described. The method for manufacturing the porous plate 1 according to this embodiment is the same as the method for manufacturing the porous plate 1 according to the first embodiment, from the step of preparing the substrate 5 (see Figure 6) to the step of removing portion 52 from portion 51 on the substrate 5 to obtain the porous portion 21 (see Figure 10).

[0075] In this embodiment, after removing part 52 from part 51, a support part 27 is prepared. Next, the porous part 21 is fixed to the support part 27. The porous part 21 is fixed to the support part 27 with the porous part 21 positioned on the main surface 27a such that the main surface 21b of the porous part 21 and the main surface 27a of the support part 27 face each other. As an example, an adhesive may be placed between the main surface 21b and the main surface 27a, and the porous part 21 may be bonded to the support part 27 with the adhesive. As another example, low-melting-point glass may be placed between the main surface 21b and the main surface 27a, and the porous part 21 may be fused to the support part 27 via the low-melting-point glass.

[0076] Next, the filling member 3 is filled into the multiple first holes 24. The filling member 3 is arranged so as to fill the inside of the first holes 24 without any gaps. At this time, the filling member 3 is arranged across the inner surface 24a of each first hole 24, the inner surface 25a of each second hole 25, the bottom surface 25b (main surface 27a) of each second hole 25, and the main surface 21a. The filling member 3 is formed to cover the entire surface of the porous portion 21 except for the main surface 21b, and the main surface 27a of the support portion 27. As an example, the filling member 3 may be filled into the multiple first holes 24 by the ALD method or the dip coat method. As a result, the porous plate 1 according to the third embodiment can be obtained.

[0077] The support portion 27 is formed separately from the porous portion 21. This improves the design flexibility of the porous plate 1. For example, the support portion 27 can be formed from a different material than the porous portion 21, enabling a design that meets the performance requirements for each application in which the porous plate 1 is used. [Differentiation]

[0078] The present invention is not limited to the embodiments described above. Modifications of the embodiments described above will be described below. For example, as shown in Figure 13, the substrate 2 may be curved. In Figure 13, for convenience of explanation, the filling member 3 is not shown. The substrate 2 has a one-dimensional curvature. That is, the substrate 2 extends along a portion of a cylindrical surface having a central axis along the Y-axis. The main surfaces 21a and 21b of the porous portion 21 are curved together with the substrate 2. The central axis of each second hole 25 is perpendicular to the main surfaces 21a and 21b. In this modification, the step of curving the substrate 2 may be performed before the step of forming the first holes 24. Specifically, the step of curving the substrate 5, which will become the substrate 2, may be performed before the step of forming the first holes 24. In this modification, the curvature of the substrate 2 allows, for example, when the porous plate 1 is used as an X-ray grid in an X-ray imaging device, diffracted X-rays emitted radially from a sample can be efficiently passed through. The substrate 2 may have a two-dimensional curvature. In other words, the substrate 2 may extend along a portion of the spherical surface.

[0079] The width of each of the multiple first holes 24 may be less than 10 nm or greater than 1000 nm. The width of each of the multiple second holes 25 may be, for example, 1000 nm or less. The shape of each of the multiple second holes 25 is not limited. For example, the shape of the second hole 25 when viewed from the Z-axis direction may be elliptical or polygonal. The arrangement and pitch of the multiple second holes 25 are not limited. For example, the multiple second holes 25 may be arranged in a square lattice. The second holes 25 may be formed by methods other than etching.

[0080] The porous portion 21 does not necessarily have a second portion 32. That is, a second hole 25 may also be formed in the portion of the porous portion 21 located along the outer edge 21c. In this case, the number of second holes 25 in the portion located along the outer edge 21c (the portion corresponding to the second portion 32) (the ratio of second holes 25 per unit volume) may be smaller than the number of second holes 25 in the first portion 31 (the ratio of second holes 25 per unit volume).

[0081] The filler member 3 may be formed from a material other than an oxide, metal compound, or resin. The filler member 3 may be filled into the first hole 24 by a method other than the ALD method or the dip-coat method. [Explanation of symbols]

[0082] 1...perforated plate, 2,5...substrate, 3...filling material, 5a...main surface, 21...perforated portion, 21a...main surface (first main surface), 21b...main surface (second main surface), 21c...outer edge, 22,27...support portion, 24...first hole, 25...second hole, 25b...bottom surface, 31...first part, 32...second part.

Claims

1. A porous portion having a first main surface, wherein a plurality of first holes opening to the first main surface and a plurality of second holes opening to the first main surface and each having a width greater than the width of each of the plurality of first holes are formed thereon, The system comprises a filling member that fills the plurality of first holes, Porous plate.

2. The porous portion includes an anodized film of valve metal or silicon. The porous plate according to claim 1.

3. The width of each of the aforementioned plurality of first holes is between 10 nm and 1000 nm. A porous plate according to claim 1 or 2.

4. The porous portion has a second main surface opposite to the first main surface, Each of the plurality of second holes is a through hole opening into the first main surface and the second main surface. A porous plate according to claim 1 or 2.

5. The substrate further has a support portion located on the opposite side of the first main surface from the porous portion and supporting the porous portion. Each of the plurality of second holes is a non-through hole having the surface of the support portion on the porous portion side as its bottom surface. A porous plate according to claim 1 or 2.

6. The support portion is formed integrally with the porous portion. The porous plate according to claim 5.

7. The support portion is formed separately from the porous portion. The porous plate according to claim 5.

8. The porous portion has a first portion in which the plurality of second holes are formed, and a second portion that is located along the outer edge of the porous portion when viewed from the thickness direction of the substrate and in which the plurality of second holes are not formed. A porous plate according to claim 1 or 2.

9. The filling member is formed of an oxide, a metal compound, or a resin. A porous plate according to claim 1 or 2.

10. The aforementioned substrate is curved. A porous plate according to claim 1 or 2.

11. A step of preparing a substrate having a main surface, A step of forming a plurality of first holes opening into the main surface in the substrate, A step of forming a plurality of second holes in the substrate that open to the main surface and each having a width greater than the width of each of the plurality of first holes, The process includes filling the plurality of first holes with a filling material, A method for manufacturing a porous plate.

12. In the step of preparing the substrate, the substrate is made of valve metal or silicon, In the step of forming the plurality of first holes, the plurality of first holes are formed by anodizing the substrate. A method for manufacturing a porous plate according to claim 11.

13. In the step of filling the aforementioned filling member, the filling member is filled into the plurality of first holes by atomic layer deposition. A method for manufacturing a porous plate according to claim 11 or 12.

14. In the step of filling the aforementioned filling member, the filling member is filled into the plurality of first holes by a dip-coating method. A method for manufacturing a porous plate according to claim 11 or 12.

15. In the step of forming the plurality of second holes, the plurality of second holes are formed by removing a part of the substrate by etching. A method for manufacturing a porous plate according to claim 11 or 12.

Images