JP2008171900A - Micro molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a profile having a plurality of stages of level difference in a molding object with high precision. <P>SOLUTION: A method for producing a micro molding includes steps of forming a shading film of first pattern on the surface of a transparent substrate, of forming a photoresist film on the shading film, of exposing the photoresist film from the back side of the transparent substrate, of exposing the photoresist film from the surface side of the transparent substrate by using a photomask corresponding to a second pattern partially overlapping the first pattern, of developing the exposed photoresist film from the opposite sides of the transparent substrate, of forming a film on the shading film exposed from a through hole formed in the photoresist film by development, and of removing the photoresist film and leaving the second pattern or its inverted pattern. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fine mold, a method for manufacturing the same, and a method for manufacturing a wiring board using the same.

Conventionally, a fine molding method using a fine molding mold, also called a stamper, is known (for example, see Patent Document 1). By using a stamper having a molding surface having a plurality of steps as described in Patent Document 1, a three-dimensional shape having a plurality of steps is formed with high accuracy and at low cost compared to a molding method using photolithography. be able to. The molding surface of the stamper is formed by pattern transfer by photolithography. As a method of forming a plurality of steps on the molding surface, a method of repeating etching and lift-off by changing a photomask pattern is known (see, for example, Patent Document 2). A stamper, photolithography, or mechanical drilling is used to form wiring grooves and through holes for forming wiring on a printed wiring board (see, for example, Patent Documents 1 to 5). .
JP 2001-196703 A JP 2003-224345 A JP 2005-158974 A JP 2001-185858 A JP 2002-237468 A

However, when the pattern of the photomask is changed and etching and lift-off are repeated to form a plurality of steps on the molding surface of the stamper, the relative position accuracy of the contour of each step is set to be higher than the alignment accuracy of the photomask. This is not possible, and the limit of miniaturization is determined in consideration of the margin of alignment. Therefore, even when a stamper is used, miniaturization of a molding object having a plurality of steps such as a printed wiring board is restricted by the alignment accuracy of the photomask. In particular, when forming a second step on a molding object using a stamper, when forming a first step, a second step, and a two-step step jumping over an intermediate step, the first step Since the photomask for forming and the photomask for forming the second stage require alignment accuracy with zero error, it is practically impossible to form such a step by changing the photomask. is there.
Further, even when a plurality of steps are formed on a molding object using photolithography or mechanical drilling, the limit of miniaturization is determined by the alignment accuracy of the photomask or the like.

  The present invention was created to solve such problems, and an object thereof is to transfer and shape a stepped shape with high accuracy.

  (1) A method for producing a fine mold for achieving the above object is to form a light-shielding film having a first pattern on the surface of a light-transmitting substrate and form a photoresist film on the light-shielding film. The photoresist film is exposed from the back side of the translucent substrate, and the photoresist film is applied to the translucent substrate using a photomask corresponding to a second pattern partially overlapping the first pattern. On the light-shielding film exposed from the through-holes formed in the photoresist film by development, developing the photoresist film exposed from both the front and back sides of the translucent substrate Forming a film, removing the photoresist film, and leaving the film of the second pattern or an inverted pattern of the second pattern.

  According to this manufacturing method, a three-step step including a step of two steps is increased on the molding surface of the fine mold by the contour of the light-shielding film of the first pattern and the contour of the photomask corresponding to the second pattern. It can be formed with high accuracy. The first step is a step between the surface of the light-transmitting substrate and the surface of the light-shielding film, and the second step is a step between the surface of the light-shielding film and the surface of the film formed thereon, The third step is a step between the surface of the light-shielding substrate and the surface of the film formed on the light-shielding film. That is, when the surface of the light-transmitting substrate is referred to as the lower surface, the surface of the light-shielding film is referred to as the middle surface, and the surface of the film formed on the light-shielding film is referred to as the upper surface, it jumps from the lower surface to the middle surface. Therefore, the step reaching the upper surface can be formed on the molding surface of the fine molding mold with high accuracy. The reason is as follows. The outline of the film formed on the light-shielding film is formed by development after the exposure using the light-shielding film of the first pattern and the exposure using the photomask corresponding to the second pattern. . Accordingly, only the film corresponding to the region shielded by both the light-shielding film of the first pattern and the photomask corresponding to the second pattern remains or is removed. As a result, a part of one contour of the light-shielding film and the film formed thereon is determined by the contour of the other film. Therefore, even if an error occurs in the alignment between the light-shielding film of the first pattern and the photomask corresponding to the second pattern, the other of the contours of the light-shielding film and the film formed thereon is the other. It does not occur at sites where no membrane is allowed to protrude. Therefore, according to the method for producing a fine mold, a molding surface having two steps on the molding surface of the fine mold can be accurately formed. A shape having three steps including two steps can be transferred and molded with high accuracy.

  In this specification, the front and back are concepts of relative positional relationship, and when a certain object is referred to as a back surface, it means a surface on the back side of a surface referred to as the front surface for that object. Further, when the terms “light-transmitting property” and “light-shielding property” are used for an object, it means light-transmitting property or light-blocking property for light having a wavelength used in an exposure process using the object as a photomask. Translucency and light-shielding properties are concepts with gradations of translucency or light-shielding rate, and can be used as a photomask to such an extent that a substantial difference occurs in the dissolution characteristics during development of the photosensitive material to be exposed. It means that the object used is transparent or opaque.

(2) In the method of manufacturing a fine mold for achieving the above object, the first pattern corresponds to a wiring groove of a wiring board to be molded, and the second pattern is a through-hole of the wiring board. It may correspond to a hall.
In this case, it is not necessary to design the wiring pattern around the through hole in consideration of the positional deviation of the through hole, and the wiring density around the through hole can be increased.

(3) In the method of manufacturing a fine mold for achieving the above object, the through hole may be a hole in which a through electrode is formed.
In this case, it is not necessary to design a wiring pattern around the through electrode in consideration of the positional deviation of the through electrode, and the wiring density around the through electrode can be increased.

(4) In the method of manufacturing a fine mold for achieving the above object, the through hole may be a hole in which a through alignment mark is formed.
In this case, since the positional relationship between the wiring groove and the through-alignment mark is determined by the first pattern, the through-alignment mark positioned with high accuracy with respect to the wiring groove can be formed on the wiring board. Since the penetrating alignment mark is exposed on both surfaces of the wiring board, the front and back alignment accuracy of the double-sided wiring substrate can be improved, and the alignment accuracy between the layers of the multilayer wiring substrate can be improved.

(5) In the method of manufacturing a fine mold for achieving the above object, the film may be thinly formed below the photoresist film by grinding or polishing after forming the film thicker than the photoresist film. .
In this case, the surface height of the film formed on the light-shielding film can be aligned with high accuracy, and the flatness or smoothness of the surface can be increased.

(6) In the method for manufacturing a fine mold for achieving the above object, the light-transmitting substrate may be etched using the light-shielding film as a protective film.
In this case, the depth of the recess formed on the molding object by transferring the pattern of the light shielding film can be made deeper than the thickness of the light shielding film.

(7) In the method of manufacturing a fine mold for achieving the above object, the light shielding film may be etched using the film as a protective film.
In this case, the step of the recess formed in the light-transmitting substrate by etching using the light-shielding film of the first pattern and the step between the upper surface of the substrate and the surface of the film formed on the light-shielding film The step between the bottom surface of the concave portion of the substrate (the lower surface of the substrate) and the surface of the film formed on the light-shielding film can be formed on the molding surface of the fine mold. That is, the lower surface of the substrate, which is the bottom surface of the concave portion of the substrate, is referred to as the lower surface, the upper surface of the substrate is referred to as the middle surface, and the surface of the film formed on the light-shielding film is referred to as the upper surface. A step that jumps from the middle step surface to the upper step surface can be formed on the molding surface of the fine molding mold with high accuracy. In addition, by using a fine mold produced by this method, a shape having three steps including two steps can be transferred and formed with high accuracy.
(8) In the method of manufacturing a fine mold for achieving the above object, after the light shielding film is etched using the film as a protective film, a part of the film may be removed by etching.
In this case, four steps can be formed on the molding surface of the fine mold by adding a step between the bottom surface of the concave portion of the substrate (the lower surface of the substrate) and the surface of the light-shielding film.

(9) A fine mold for achieving the above object includes a light-transmitting substrate, a light-shielding film bonded to the surface of the light-transmitting substrate, and the light-shielding property bonded onto the light-shielding film. The film and the film whose outlines partially overlap each other, and a molding surface having three steps including two steps is formed by the translucent substrate, the light-shielding film, and the film.
According to this fine molding mold, the first step, the second step, and the two steps over the first step can be formed on the molding object with high accuracy. In this case, the two steps are formed at the part of the molding object corresponding to the part where the contour of the light-shielding film and the contour of the film bonded thereon overlap.

(10) In a fine mold for achieving the above object, the pattern of the light-shielding film corresponds to a wiring groove of a wiring board to be molded, and the pattern of the film corresponds to a through hole of the wiring board May be.
In this case, it is not necessary to design the wiring pattern around the through hole in consideration of the positional deviation of the through hole, and the wiring density around the through hole can be increased.

(11) In the fine mold for achieving the above object, the translucent substrate has at least one step on the surface, and the light shielding film is formed on the surface of the translucent substrate. A step with respect to the upper surface of the translucent substrate may be formed by bonding to the upper surface.
In the molding process using this fine mold, the step of the translucent substrate itself can be transferred to the photosensitive resin by pressing the fine mold against the photosensitive resin, and the photosensitive resin is exposed using a light-shielding film. By developing, a through hole deeper than the thickness of the light-shielding film can be formed in the photosensitive resin along the outline of the light-shielding film. When forming a through hole in this way, the through hole surely penetrates the photosensitive resin, and no burr is generated around the through hole by mechanical processing.

(12) In the fine molding mold for achieving the above object, the pattern of the upper surface of the surface of the translucent substrate corresponds to a wiring groove of the wiring substrate to be molded, and the light shielding film The pattern may correspond to the through hole of the wiring board.
In this case, it is not necessary to design the wiring pattern around the through hole in consideration of the positional deviation of the through hole, and the wiring density around the through hole can be increased.

(13) A method for manufacturing a wiring board for achieving the above object is a method for manufacturing a wiring board using the fine mold described in (10) above, wherein the fine mold is pressure-bonded to a photosensitive resin film. Then, the photosensitive resin film is exposed using the light-transmitting substrate and the light-shielding film as a photomask, the exposed photosensitive resin film is developed, and the photosensitive resin film formed by development is passed through. Filling the holes with a conductive material.
When the through hole corresponding to the pattern of the light shielding film is formed in this way, the through hole surely penetrates the photosensitive resin, and no burr is generated around the through hole by mechanical processing.

Hereinafter, embodiments of the present invention will be described in the following order with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the corresponding component in each figure, and in the following description, a micromolding mold shall be called a stamper, and the overlapping description is abbreviate | omitted.
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1. Basic principle 2. First embodiment of stamper configuration 3. First embodiment of stamper manufacturing method 4. First embodiment of manufacturing method of wiring board 5. Second embodiment of stamper configuration 6. Third embodiment of stamper configuration 7. Fourth embodiment of stamper configuration 8. Fifth embodiment of stamper configuration 9. Second embodiment of stamper manufacturing method 10. Second embodiment of manufacturing method of wiring board Other Embodiments ***********

1. Basic Principle FIGS. 1 to 6 are diagrams showing a basic process for accurately molding a stamper having a molding surface having a plurality of steps including two steps. Each partial view (A) is a plan view, and each partial view (B) and FIG. 3 (C) are cross-sectional views having a common cut surface.
In a plurality of embodiments to be described later, a photoresist film containing a photosensitive resin is exposed from both the front and back sides of a translucent substrate in order to accurately form a molding surface having two steps. The main points are as follows.

  First, as shown in FIG. 1, light-shielding films 100 and 101 having a specific pattern that constitutes the convex portions of the stamper are formed on the surface of the translucent substrate 103. For example, a portion denoted by reference numeral 100 corresponds to a linear wiring groove formed on the surface of the wiring board, and a portion denoted by reference numeral 101 corresponds to, for example, a through hole of the wiring board. As materials for the light-shielding films 100 and 101, inorganic materials such as metals, metal compounds, ceramics, and the like corresponding to hardness, brittleness, and thermal conductivity required for the stamper are employed. The material of the light-transmitting substrate 103 is a material that transmits light used in the exposure process using the light-transmitting substrate 103 and the light-shielding films 100 and 101 as a photomask to such an extent that a photochemical reaction occurs in the photoresist film. Adopted.

  Next, a photoresist containing a photosensitive resin is applied on the light-shielding films 100 and 101 and the exposed portion of the surface of the light-transmitting substrate 103, and the light-shielding films 100 and 101 and the light-transmitting substrate 103 are exposed. A photoresist film 102 is formed thereon. Hereinafter, the photoresist film 102 will be described as a negative type, but a positive type may be used.

  Next, as shown in FIG. 2B, the photoresist film 102 is exposed from the back side of the translucent substrate 103. At this time, since the light-transmitting substrate 103 and the light-shielding films 100 and 101 function as a photomask, as shown in FIGS. 2A and 2B, the light-shielding films 100 and 101 of the photoresist film 102 and The non-overlapping region 1021 is exposed, and the regions 1020 and 1022 of the photoresist film 102 overlapping the light-shielding films 100 and 101 are not exposed.

  Next, as shown in FIGS. 3A and 3B, the photomask 104 in which the light-shielding film 1041 is bonded to the light-transmitting substrate 1040 is aligned with the light-transmitting substrate 103. In this alignment step, alignment is performed using a light-shielding alignment mark formed on the surface of the translucent substrate 103 or the like, but the alignment accuracy is governed by the alignment accuracy inherent to the stepper or aligner. FIG. 3 shows a state in which the photomask 104 having the light-shielding film 1041 that should completely overlap with the light-shielding film 101 is aligned with respect to the light-transmitting substrate 103 including an error. In the present specification, “photomask” means a reticle, resist mask, or the like that forms a shadow of a specific pattern on an exposure object in an exposure process.

  Next, as shown in FIG. 3C, when the photoresist film 102 is exposed from the front side of the translucent substrate 103, the exposed region 1021 is enlarged and the unexposed region 1022 is reduced. As a result, the unexposed region 1022 of the photoresist film 102 is only a region where the light shielding films 100 and 101 constituting the stamper convex portion and the light shielding film 1041 of the photomask 104 overlap. When exposing the photoresist film 102 from both the front and back sides of the translucent substrate 103, the front and back sides may be exposed first.

  Next, when the photoresist film 102 is developed as shown in FIG. 4, the exposed region 1021 remains and a through hole 1023 is formed in the portion where the unexposed region 1022 is removed, and the light shielding film 101 is exposed from the through hole 1023. .

  Next, as shown in FIG. 5, a film 105 is formed on the light-shielding film 101 exposed from the through hole 1023 of the photoresist film 102. The film 105 is a film for forming a recess or a through hole deeper than the thickness of the light-shielding films 100 and 101 in the object to be molded, and is a metal or metal corresponding to the hardness, brittleness, or thermal conductivity required for the stamper. Inorganic materials such as compounds and ceramics are employed as the material. Depending on the film formation method, the film 105 is also formed on the surface of the photoresist film 102. Further, after the film 105 is formed, both the surface layer of the photoresist film 102 and the surface layer of the film 105 may be removed by grinding or polishing, and the surface of the film 105 may be flattened or smoothed.

  Next, when the photoresist film 102 is removed, the stamper 106 is completed as shown in FIG.

  The stamper 106 manufactured in this way is provided with a molding surface having two steps as shown in FIG. The lower surface is the surface of the translucent substrate 103, and the step S101 between the lower surface and the middle surface corresponds to the thickness of the light shielding films 100 and 101. The middle surface is the surface of the light shielding films 100 and 101, and the step S100 between the middle surface and the upper surface corresponds to the thickness of the film 105 bonded on the light shielding film 101. In the case of forming the step S100 between the middle step surface and the upper step surface, the pattern of the light shielding film 1041 of the photomask 104 and the pattern of the light shielding film 101 may be different. In the case where the step S100 between the middle surface and the upper surface is not formed, the pattern of the light shielding film 101 may be included in the pattern of the light shielding film 1041 of the photomask 104. Since the film 105 constituting the upper surface of the stamper 106 is formed using the light-transmitting substrate 103 and the light-shielding films 100 and 101 as a photomask, the film 105 protrudes from the light-shielding films 100 and 101. It is a film that does not get stuck. Therefore, the pattern of the light-shielding films 100 and 101 does not need to be a pattern with a margin in anticipation of the film 105 protruding from the light-shielding films 100 and 101, and should be made finer than the case where the margin is taken. it can.

  Further, the stamper 106 is formed with a step S102 that jumps from the lower step surface to the upper step surface. That is, the stamper 106 is formed with three types of steps S100, S101, and S102 having different heights from the two-layer film laminated on the flat translucent substrate 103. In order to form three types of steps having different heights from the two-layer film as described above, it is required that there is a portion that completely overlaps in the outline of the two-layer film. By exposing the photoresist film 102 from both the front and back sides, the contour of the light-shielding film 101 and the contour of the film 105 bonded thereto overlap in a self-aligning manner.

2. First Embodiment of Stamper Configuration A stamper 1 shown in FIG. 16 is a fine molding mold used for manufacturing a wiring board having a through electrode and a through alignment mark. The portion 110 of the light shielding film 11 constitutes a convex portion for forming a wiring groove filled with a conductive material. The portion 111 of the light-shielding film 11 constitutes a convex portion for forming a wiring groove connected to the through electrode. The portion 112 of the light shielding film 11 constitutes a convex portion for forming the lower step portion of the through alignment mark. A portion 131 of the film 13 bonded to the surface of the portion 111 of the light shielding film 11 constitutes a convex portion for forming a through hole in which a through electrode is formed. The portion 130 of the film 13 bonded to the surface of the portion 112 of the light shielding film 11 constitutes a convex portion for forming the upper stage portion of the through alignment mark.

3. First Embodiment of Stamper Manufacturing Method Hereinafter, a method for manufacturing the stamper 1 shown in FIG. 16 will be described.
FIGS. 7 to 15 show steps for manufacturing the stamper 1 shown in FIG. 16, and each partial view (A) is a cross-sectional view corresponding to the symbol A in FIG. 16 (C), and each partial view (B). These are sectional drawings corresponding to the code | symbol B of FIG.16 (C), and each division figure (C) is a top view.

First, as shown in FIG. 7, a light-shielding film 11 such as a metal, a metal oxide, a semiconductor, a semiconductor compound, or a silicide compound is formed on the surface of a translucent substrate 10 such as quartz, soda lime glass, or transparent crystallized glass. . Specifically, the light-shielding film 11 made of, for example, Cr, CrO ₂ , Cu, amorphous Si, polycrystalline Si, SiN, SiON, MoSi, NiSi, or WSi is formed by sputtering, vapor deposition, CVD, or the like. Moreover, the thickness of the translucent board | substrate 10 shall be 2 mm, for example. The thickness of the light-shielding film 11 is set equal to the height of the step S1 (see FIG. 16) of the stamper 1 corresponding to the depth of the wiring groove, for example, 1 μm. The light shielding film 11 may be a single layer film or a multilayer film. A photomask material substrate in which Cr and CrO _x are laminated on a translucent substrate made of quartz or glass may be used.

  Next, as shown in FIG. 8, a photoresist film 12 having a first pattern to be transferred to the light shielding film 11 is formed on the surface of the light shielding film 11. For example, a photoresist is applied in a thickness of 1 μm, and exposure is performed using a stepper or aligner to develop the photoresist film 12 having a pattern with a line width of 25 μm and a line interval of 25 μm. An electron beam exposure method or a laser direct drawing method may be used for patterning the photoresist film 12.

  Next, as shown in FIG. 9, the light-shielding film 11 is etched using the photoresist film 12 as a protective film to form convex portions 110, 111, and 112 on the molding surface of the stamper. The etching method may be anisotropic etching such as ion milling or isotropic etching of the Cr film with a ceric ammonium nitrate aqueous solution.

Next, the photoresist film 12 is removed as shown in FIG. Specifically, for example, the photoresist film 12 is removed using NMP (N-methyl-2 pyrrolidone), acetone, O ₂ plasma, an amine organic stripping solution, or the like.

  A groove is formed on the surface of the light-transmitting substrate 10 by machining, the groove is backfilled with the light-shielding film 11, and a portion protruding from the groove of the light-shielding film 11 is removed by grinding or polishing. A pattern of the light shielding / light shielding film 11 may be formed.

  Next, as shown in FIG. 11, a second photoresist film 14 is formed on the light shielding film 11. Specifically, a photosensitive resin such as a chemically amplified negative resist or photosensitive polyimide is applied and prebaked to form a photoresist film 14. The photoresist film 14 is formed thicker than the height of the stamper step S2 (see FIG. 16), and is set to a thickness of, for example, 70 μm.

  Next, as shown in FIG. 12, the photoresist film 14 is exposed from the back side of the translucent substrate 10 (that is, the back side of the surface to which the light shielding film 11 is bonded). The light used for exposure may be visible light, ultraviolet light, or both. At this time, since the light-transmitting substrate 10 and the light-shielding film 11 function as a photomask, a region 141 of the photoresist film 14 that does not overlap the light-shielding film 11 is exposed, and the light-shielding film 11 of the photoresist film 14 is exposed. The overlapping area 140 is not exposed.

  Next, as shown in FIG. 13, the photoresist film 14 is translucent using a photomask 15 in which light-shielding films 151 and 152 whose patterns partially overlap with the light-shielding film 11 are bonded to the light-transmissive substrate 150. Exposure is performed from the front side of the conductive substrate 10. That is, light is irradiated from the direction where the light-shielding film 11 is bonded to the light-transmitting substrate 10. At this time, the exposed region 141 of the photoresist film 14 is enlarged, the unexposed region 140 is reduced, and the light-shielding film 11 constituting the convex portion of the stamper 1 and the light-shielding film 151 of the photomask 15 are overlapped. Only the unexposed area 140 remains. In this embodiment, even if an alignment error between the photomask 15 and the translucent substrate 10 occurs, the light-shielding film 111 to the light-shielding film 152 prevent the convex portion 131 (see FIG. 16) of the stamper 1 from thinning. A photomask 15 that protrudes is used. Even if the region of the light-shielding film 152 that protrudes from the light-shielding film 111 is provided, the convex portion 131 of the stamper 1 is not formed in that region (see the region 132 in FIG. 16).

  Next, as shown in FIG. 14, the exposed photoresist film 14 is developed from both the front and back sides of the translucent substrate 10 to remove the unexposed areas 140 to form through holes 142 and 143. , 143, the light shielding film 11 is exposed.

  Next, as shown in FIG. 15, the film 13 is formed by plating on the portions of the light-shielding film 11 exposed from the through holes 142 and 143. Specifically, for example, an alloy such as NiFe is deposited in the through holes 142 and 143 by electrolytic plating, electroless plating, pulse plating, or the like. Sputtering or vapor deposition may be used as a method for forming the film 13. Note that the film 13 may be formed thicker than the photoresist film 14. When forming the film 13 thicker than the photoresist film 14, the surface layer of the film 13 is removed together with the surface layer of the photoresist film 14 by grinding or polishing. In order to flatten or smooth the surface layer of the film 13, the film 13 may be ground or polished.

  Finally, when the photoresist film 14 is removed, the stamper 1 shown in FIG. 16 is completed.

4). First Embodiment of Manufacturing Method of Wiring Substrate FIGS. 17 to 27 are diagrams showing steps of manufacturing the single-sided wiring substrate 19 shown in FIG. 22 and the double-sided wiring substrate 23 shown in FIG. Each partial view (A) and each partial view (B) are cross-sectional views corresponding to the cut surface A and the cut surface B of FIG.

  First, as shown in FIG. 17, a molding target film 16 made of a thermosetting resin, a thermoplastic resin, a room temperature curable silicone rubber, or a photocurable resin is formed on a substrate 180. In the present embodiment, description will be made assuming that a PMMA coating having a thickness of 70 μm is formed on the substrate 180. The substrate 180 may be light-shielding, but will be described as being light-transmitting. An alignment mark 181 is formed on the surface of the substrate 180.

  Next, as shown in FIG. 18, the molding target film 16 is softened, the stamper 1 is aligned with the substrate 180, and the stamper 1 is pressure-bonded to the molding target film 16. Specifically, the PMMA is heated and softened to 150 ° C., and the convex portion 130 as the alignment mark of the stamper 1 is aligned with the alignment mark 181 of the substrate 180. At this time, the alignment mark 181 and the convex portion 130 may be seen through through the translucent substrate 10 of the stamper 1, or the alignment mark 181 and the convex portion 130 may be seen through through the translucent substrate 180. Good. The stamper 1 is held by a holder (not shown) and is pressed against the molding target film 16 with a pressure of 10 MPa.

  Next, the molding target film 16 is cured, and the stamper 1 is released as shown in FIG. As a result, an uneven surface 161 onto which the molding surface F1 of the stamper 1 is transferred is formed on the molding target film 16. In FIG. 19, the molding surface F1 is indicated by a bold line. In this state, no through hole is formed in the molding target film 16.

  Next, the surface layer of the molding target film 16 is removed by etching to form a substrate 190 shown in FIG. Specifically, for example, anisotropic etching using enzyme plasma is performed. At this time, the surface layer of the molding target film 16 is removed so that the uneven surface 161 (see FIG. 19) formed by the molding surface F1 of the stamper 1 translates in a direction perpendicular to the surface of the substrate 180. When the surface layer of the molding target film 16 is removed until the through holes 194 and 195 are formed, the substrate 190 of the single-sided wiring substrate 19 is completed. The end point of etching is set according to the finished thickness of the substrate 190, and the depth of the through holes 194 and 195 may be shallower than the height of the convex portions 130 and 131 of the stamper 1. In addition to the through holes 194 and 195, the substrate 190 is formed with recesses 196, 197, and 198 having a shape along the molding surface F1 of the stamper 1. The recess 196 and the through hole 195 are for forming a penetration alignment mark. The through hole 194 is for forming a through electrode. The recess 198 assimilated with the through hole 194 is for forming a trench for wiring connected to the through electrode. The recess 197 is a wiring groove.

  Next, the recesses 196, 197, 198 and the through holes 194, 195 of the substrate 190 are filled with a conductive material, and as shown in FIG. 21, the through electrode 192, the through alignment mark 191 and the wirings 193, 199 are formed. . Specifically, for example, after a conductive film is formed on the surface of the substrate 180 by electroless plating, portions protruding from the recesses 196, 197, and 198 and the through holes 194 and 195 of the conductive film are removed by grinding or polishing. The conductive film may be formed by electrolytic plating after the plating seed layer is formed on the surface of the substrate 180 by sputtering or vapor deposition. When the liquid crystal polymer, polyetheretherketone (PEEK), thermoplastic polyimide (modified PI), polyphenylsulfone (PPS), syndiotactic polystyrene (SPS), etc. are used as the material of the substrate 190, a conductive material. A conductive paste can also be applied. Silver, copper, gold, platinum, palladium, or the like is selected as the plating material and the metal filler of the conductive paste.

  Finally, peeling from the substrate 180 completes the single-sided wiring board 19 shown in FIG. By using the through electrode 192 and the through alignment mark 191 of the single-sided wiring board 19, wiring can be formed on the back side or laminated to form a multilayer wiring board.

Next, a method for manufacturing the double-sided wiring board 23 shown in FIG. 27 will be described.
First, as shown in FIG. 23, the sacrificial substrate 20 is bonded to the surface of the single-sided wiring substrate 19 (the surface on which the wiring is formed). Double-sided tape, adhesive, etc. are used for joining.
Next, as shown in FIG. 24, the molding target film 16 is formed on the back surface of the single-sided wiring board 19.

  Next, the molding target film 16 is softened, and the stamper 1 is pressure-bonded to the molding target film 16 as shown in FIG. At this time, the through-electrodes 192 and 221 (see FIG. 26) can be made with high accuracy by aligning the convex portion 130 as the alignment mark of the stamper 1 with the through-alignment mark 191 exposed on the back surface of the single-sided wiring board 19. Can be connected.

  Thereafter, the molding target film 16 is cured, the stamper 1 is released, and a conductive material is introduced into the recess as shown in FIG. 26 to form the through electrode 192, the through alignment mark 220, and the wirings 223 and 224. As a result, another single-sided wiring board 22 is formed on the single-sided wiring board 19.

  Finally, when the sacrificial substrate 20 is peeled off, the double-sided wiring substrate 23 shown in FIG. 27 is completed. Although the patterns of the single-sided wiring boards 19 and 22 are illustrated as being the same, it goes without saying that the patterns may be different. For example, the wiring groove pattern may be changed, or the front and back alignment marks may be changed so as not to penetrate the alignment mark.

5. Second Embodiment of Stamper Configuration A through hole is not necessarily required in a single-sided wiring board. For example, like the stamper 2 shown in FIG. 28, the height of the convex portion 112 for forming the concave portion for forming the alignment mark and the height of the convex portion 110 for forming the wiring groove may be aligned. The stamper 2 can be manufactured by changing the pattern of the light-shielding film 151 of the photomask 15 shown in FIG.

6). 3rd embodiment of the structure of a stamper.
After the step shown in FIG. 15, a film 133 having a hardness higher than that of the film 13 is formed on the film 13 as shown in FIG. 29, and the tip hardness of the convex portion for forming the alignment mark and the through-hole of the through electrode is formed. The stamper 3 shown in FIGS. 30 and 31 can be manufactured. 30 (A) and (B) correspond to cut planes A and B in FIG. 31, respectively.

7). Fourth Embodiment of Stamper Configuration In order to form the wiring groove deeper than the thickness of the light shielding film, as shown in FIG. 32, the surface of the light transmissive substrate 10 exposed from the opening of the light shielding film 11 is formed. The recess 109 may be formed. That is, the stamper 4 in which a step is formed on the surface of the translucent substrate 10 and the light shielding film 11 is bonded to the upper step surface of the translucent substrate 10 can be manufactured. In order to form the recess 109 on the surface of the light-transmitting substrate 10, the light-transmitting substrate 10 may be etched using the light-shielding film 11 as a protective film. Specifically, for example, the translucent substrate 10 is anisotropically etched by RIE using a gas containing CF ₄ as a main component.

8). Fifth Embodiment of Stamper Configuration The configuration of the stamper 5 shown in FIG. 33 may be employed in order to form the wiring groove and the concave portion of the alignment mark by a step of the translucent substrate instead of the light shielding film. The stamper 5 is obtained by etching away a portion exposed from the film 13 of the light shielding film 11 of the stamper 4 shown in FIG. Specifically, the light-shielding film 11 is anisotropically removed by ion milling using the metal film 13 as a protective film, or the light-shielding film 11 made of Cr isotropic using an aqueous solution of ceric ammonium nitrate as an etchant. Thus, the stamper 5 shown in FIG. 33 can be manufactured.

9. Second Embodiment of Stamper Manufacturing Method FIGS. 34 and 35 are cross-sectional views showing steps for manufacturing the stamper 6 shown in FIG. Each partial drawing (A) and (B) has shown the cut surface orthogonal to each other.
After the stamper 5 shown in FIG. 33 is manufactured as an intermediate, a portion 131 of the metal film 13 to be left is covered with a protective film 24 as shown in FIG.
Next, as shown in FIG. 35, the protrusion 130 which is a portion of the film 13 not covered with the protective film 24 is removed by etching.
Finally, when the protective film 24 is removed, the stamper 6 shown in FIG. 36 is completed.

10. Second Embodiment of Manufacturing Method of Wiring Board FIGS. 37 to 41 are diagrams showing steps of manufacturing the single-sided wiring board 19 shown in FIG. This manufacturing method is a method of forming a through hole in the substrate 190 using the convex portion 112 of the stamper 6 that is lower than the finished thickness of the substrate 190 of the single-sided wiring substrate 19.

  First, as shown in FIG. 37, a molding target film 16 containing a photosensitive resin is formed on a substrate 180, and the stamper 6 is pressure-bonded to the molding target film 16.

  Next, as shown in FIG. 38, the molding target film 16 is exposed from the back side of the translucent substrate 10 of the stamper 6 using the translucent substrate 10 and the light-shielding film 11 as a photomask. As a result, the region 163 of the molding target film 16 that does not overlap the light shielding film 11 is exposed, and the region 164 of the molding target film 16 that overlaps the light shielding film 11 is not exposed.

  Next, as shown in FIG. 39, when the stamper 6 is released, an uneven surface 165 to which the molding surface F6 of the stamper 6 is transferred is formed on the molding target film 16. In FIG. 39, the molding surface F6 is indicated by a bold line.

  Next, when the molding target film 16 is developed, the exposed region 163 of the molding target film 16 remains and the non-exposed region 164 is removed as shown in FIG. 40. As a result, the substrate having the through holes 166 and 167 is removed. 168 is formed.

  Finally, a conductive material is filled in the through-holes 166 and 167 and the recesses such as the wiring grooves 197 and peeled from the substrate 180, thereby completing the single-sided wiring substrate 19 shown in FIG.

  According to this manufacturing method, since the elongated through hole can be formed in the object to be molded without forming the elongated protrusion on the stamper, the number of times the stamper can be used can be increased.

11. Other Embodiments The technical scope of the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the scope of the present invention. For example, it is needless to say that the stamper as a fine mold according to the present invention can be used for molding a molded product other than the substrate of the wiring board (for example, MEMS). In addition, the materials, dimensions, film forming methods, and pattern transfer methods shown in the above embodiment are merely examples, and descriptions of addition and deletion of processes and replacement of process order that are obvious to those skilled in the art are omitted. ing.

It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) is sectional drawing. It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) is sectional drawing. It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) and (C) are sectional drawings. It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) is sectional drawing. It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) is sectional drawing. It is a figure concerning embodiment of this invention, Comprising: (A) is a top view, (B) is sectional drawing. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is a figure concerning embodiment of this invention, Comprising: (A) And (B) is sectional drawing, (C) is a top view. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is a figure concerning embodiment of this invention, Comprising: (A) And (B) is sectional drawing, (C) is a top view. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is a figure concerning embodiment of this invention, Comprising: (A) And (B) is sectional drawing, (C) is a top view. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is a figure concerning embodiment of this invention, Comprising: (A) And (B) is sectional drawing, (C) is a top view. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is a top view concerning the embodiment of the present invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention. It is sectional drawing concerning embodiment of this invention.

Explanation of symbols

1: Stamper, 2: Stamper, 3: Stamper, 4: Stamper, 5: Stamper, 6: Stamper, 10: Translucent substrate, 11: Light-shielding film, 12: Photoresist film, 13: Film, 14: Photo Resist film, 15: photomask, 16: molding target film, 19: single-sided wiring board, 20: sacrificial board, 22: single-sided wiring board, 23: double-sided wiring board, 24: protective film, 100: light-shielding film, 101: Light-shielding film, 102: Photoresist film, 103: Translucent substrate, 104: Photomask, 105: Film, 106: Stamper, 109: Concavity, 110: Convex, 112: Light-shielding film, 130: Convex 131: convex portion, 133: film, 140: unexposed area, 141: exposed area, 142: through-hole, 150: translucent substrate, 151: light-shielding film, 161: uneven surface, 165: uneven surface, 166: Through hole 167: Through hole, 168: Substrate, 180: Substrate, 181: Alignment mark, 190: Substrate, 191: Through alignment mark, 192: Through electrode, 193: Wiring, 194: Through hole, 195: Through hole, 196: Recess 197: wiring groove, 198: recess, 220: penetrating alignment mark, 223: wiring, 1021: exposed area, 1022: unexposed area, 1023: through hole, 1040: translucent substrate, 1041: light shielding film, F1 : Molded surface, F6: Molded surface

Claims (13)

Forming a light-shielding film of the first pattern on the surface of the translucent substrate;
Forming a photoresist film on the light-shielding film;
Exposing the photoresist film from the back side of the translucent substrate;
Exposing the photoresist film from the front side of the translucent substrate using a photomask corresponding to a second pattern partially overlapping the first pattern;
Develop the exposed photoresist film from both sides of the translucent substrate,
Forming a film on the light-shielding film exposed from the through-hole formed in the photoresist film by development;
Removing the photoresist film and leaving the film of the second pattern or an inverted pattern of the second pattern;
The manufacturing method of the fine mold which contains this. The first pattern corresponds to the wiring groove and the through hole of the wiring board to be molded,
The second pattern corresponds to the through hole,
The manufacturing method of the fine mold according to claim 1. The through hole is a hole in which a through electrode is formed,
The manufacturing method of the fine mold according to claim 2. The through hole is a hole in which a through alignment mark is formed,
The manufacturing method of the fine mold according to claim 2. Forming the film thinly below the photoresist film by grinding or polishing after forming the film thicker than the photoresist film;
The manufacturing method of the fine shaping | molding mold as described in any one of Claim 1 to 4 including this. Etching the translucent substrate using the light-shielding film as a protective film;
The manufacturing method of the fine shaping | molding mold as described in any one of Claim 1 to 5 including this. Etching the light-shielding film using the film as a protective film;
The manufacturing method of the fine mold according to claim 6. After etching the light-shielding film using the film as a protective film,
Removing a part of the film by etching;
The manufacturing method of the fine shaping | molding mold of Claim 7 including this. A translucent substrate;
A light-shielding film bonded to the surface of the translucent substrate;
A film that is bonded onto the light-shielding film and that overlaps a part of the contour with the light-shielding film,
A molding surface having three steps including two steps is formed by the translucent substrate, the light-shielding film, and the film.
Fine molding mold. The light-shielding film pattern corresponds to the wiring groove of the wiring board to be molded,
The pattern of the film corresponds to the through hole of the wiring board,
The fine mold according to claim 9. The translucent substrate has at least one step on the surface,
The light-shielding film is bonded to the upper surface of the surface of the translucent substrate;
The fine mold according to claim 9. The pattern on the upper surface of the surface of the translucent substrate corresponds to the wiring groove of the wiring substrate to be molded,
The pattern of the film formed on the light shielding film corresponds to the through hole of the wiring board.
The fine mold according to claim 11. A method of manufacturing a wiring board using the fine mold according to claim 11,
Crimp the fine mold to the photosensitive resin film,
The photosensitive resin film is exposed using the light-transmitting substrate and the light-shielding film as a photomask,
Develop the exposed photosensitive resin film,
Fill the through hole of the photosensitive resin film formed by development with a conductive material,
The manufacturing method of the wiring board including this.

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