JP4696589B2 - Optical waveguide forming substrate - Google Patents

Description

  The present invention relates to an optical waveguide forming substrate.

  As optical components in the field of optical communication that have been attracting attention in recent years, there are optical branching couplers (optical couplers), optical multiplexers / demultiplexers, and the like, and optical waveguide devices used for these are promising. As this optical waveguide type element, there is a polymer optical waveguide which is easy to manufacture (patterning) and has a high versatility in addition to a conventional silica optical waveguide, and the latter has been actively developed in recent years.

  Such an optical waveguide device (also simply referred to as “optical waveguide”) is usually formed on a substrate and handled as an optical waveguide forming substrate. As this optical waveguide forming substrate, a predetermined wiring circuit and an optical waveguide composed of a core portion and a cladding portion are formed on a hard substrate, and a light emitting element and a light receiving element are attached to the optical waveguide. It is disclosed (for example, see Patent Document 1).

However, the optical waveguide forming substrate described in Patent Document 1 below has the following problems.
1. Since the optical waveguide and wiring circuit are all formed on a hard substrate, when using a part of the optical waveguide forming substrate as a connector, the arrangement of the optical waveguide forming substrate and the connection of the connector to the electronic device to be mounted Due to restrictions on positioning, optical waveguide arrangement, wiring circuit arrangement, etc., the degree of design freedom (allowable range) becomes narrow on each of the structure, optical circuit, and electric circuit.
2. Since the optical waveguide substrate is hard and does not have flexibility, it cannot be mounted across a fixed part (for example, a base) and a movable part (for example, an optical pickup) of an electronic device. For this reason, the target range to which the optical waveguide forming substrate can be applied is narrow.
3. The optical waveguide forming substrate is thick, the manufacturing process is complicated, and the yield is low.
4). The selection range of wiring patterns is narrow and the versatility is poor.

JP 2004-146602 A

  An object of the present invention is to provide an optical waveguide forming substrate that has a wide range of design flexibility such as an application target range and a circuit configuration and is easy to manufacture.

Such an object is achieved by the present invention described in the following (1) to ( 13 ).
(1) A plate-shaped optical waveguide forming substrate,
An optical waveguide composed of a core layer having a core part and a clad part having different refractive indexes and clad layers respectively formed on both surfaces of the core layer, and an inner conductor layer formed on each of the clad layers An insulating layer formed on each inner conductor layer, a hard substrate bonded to each insulating layer via an adhesive layer, and an outer conductor formed on each hard substrate. A laminated structure having a layer,
The laminated structure is formed by removing a part of each of the hard substrates in the middle of the longitudinal direction , and a flexible part capable of bending deformation, and the remaining parts excluding the flexible part divided into a hard portion made of a part,
The hard portion includes an opening formed by opening the hard substrate, the adhesive layer, and the insulating layer together on one surface side of the core layer, and the core of the outer conductor layers. A conductor post penetrating the hard substrate, the adhesive layer and the insulating layer, electrically connecting the outer conductor layer located on one side of the layer and the inner conductor layer;
In the opening, an element having a plate shape and having a light emitting part or a light receiving part arranged on the core layer side surface and a pair of terminals is installed,
The optical waveguide substrate according to claim 1, wherein at least one of the pair of terminals is electrically connected to the inner conductor layer .

(2) The outer conductor layer located on one surface side of the core layer among the outer conductor layers has two wires insulated from each other, and one of the two wires is the wire Electrically connected to the inner conductor layer via a conductor post;
One terminal of the pair of terminals is disposed on a surface of the element on the core layer side, and the other terminal is disposed on a surface opposite to the one terminal,
In the element, the one terminal is electrically connected to the inner conductor layer by wire bonding with a metal wire, and the other terminal is connected to the other of the two wirings by soldering. By being electrically connected and energizing between the one wiring and the other wiring, the one terminal and the other terminal are energized, and the light emitting unit or the light receiving unit operates. The optical waveguide forming substrate according to (1) above.

(3) The optical waveguide forming substrate according to (1) or (2), wherein the core portion of the optical waveguide has a pattern shape overlapping the light emitting portion or the light receiving portion in plan view .

(4) The optical waveguide forming substrate according to (3), wherein the optical waveguide has a reflective surface inclined with respect to the optical path of the optical waveguide at a portion corresponding to the light emitting unit or the light receiving unit .

(5) The optical waveguide formation according to (4), wherein the reflection surface is formed across the core layer and a clad layer located on one surface side of the core layer among the clad layers. substrate.

(6) The optical waveguide forming substrate is used by being installed in an electronic device having a main body part and a movable part movable with respect to the main body part,
At least two of the hard parts are provided, one of the two hard parts is installed on the main body part, and the other hard part is installed on the movable part. (5) The optical waveguide forming substrate according to any one of (5).

(7) Each said insulating layer is an optical waveguide formation board in any one of said (1) thru | or (6) which has a function which bears the intensity | strength of the said flexible part, respectively.

(8) The optical waveguide substrate according to any one of (1) to (7), wherein each of the insulating layers has a function of protecting the optical waveguide.

(9) The optical waveguide forming substrate according to any one of (1) to (8), wherein the core portion is made of a material having a higher refractive index than the cladding portion and the cladding layers.

(10) The optical waveguide forming substrate according to (9), wherein the constituent materials of the clad part and the clad layers have the same or similar refractive indexes.

( 11 ) The core part selectively irradiates the active energy beam or electron beam to a core layer made of a material whose refractive index changes by irradiation with an active energy beam or electron beam or by further heating. The optical waveguide forming substrate according to any one of (1) to (10) , wherein the substrate is formed into a desired shape.

( 12 ) The optical waveguide forming substrate according to (11) , wherein the core layer is made of a resin composition containing a cyclic olefin resin.

( 13 ) The optical waveguide forming substrate according to (12) , wherein the cyclic olefin-based resin is mainly a norbornene-based resin.

  According to the present invention, since it has a hard portion and a flexible portion, it is possible to provide an optical waveguide forming substrate that can be manufactured easily with a wide range of applications and design flexibility of the optical waveguide forming substrate. Such an optical waveguide forming substrate of the present invention can be used for various electronic parts, electronic devices, etc., and has a wide range of design of electric circuit design, optical circuit (optical waveguide pattern), etc. Rich.

  In addition, since the optical waveguide forming substrate of the present invention includes an element (light emitting element or light receiving element) and an optical waveguide, the light emitted from the light emitting portion of the element is optically connected to the optical waveguide through the optical waveguide. The light can be guided to other places or the light from the other places can be guided to the light receiving portion of the element by the optical waveguide, and a small and integrated optical circuit can be formed.

  In addition, since the element is mounted on the hard part, the element can be mounted stably and reliably, and the reliability of the element can be maintained.

  In particular, when the light emitting part or the light receiving part of the element is installed so as to be positioned inside the hard part, the light emitting part and the light receiving part can be effectively protected from dirt, scratches, deterioration, and the like. Further, when the device is installed so that almost the entire element is located inside the hard portion, the entire device is protected, and the same effect as described above can be obtained, and the thin hard portion (optical waveguide forming substrate) can be obtained. Contributes to reduction in thickness).

  In addition, when an element is inserted into the opening of the substrate, the alignment of the element with respect to the substrate can be performed easily and accurately, and in particular, the alignment in the thickness direction as well as the surface direction of the substrate can be performed easily and accurately. it can. When the element is installed by being inserted into the opening of the substrate, it is easy to align the element when the element is mounted on the substrate, and contributes to the thinning of the optical waveguide forming substrate.

  In addition, when the conductor layer is formed, wiring to the element is easy, and wiring suitable for the element is possible regardless of the type of the element (terminal installation location), and the versatility is high. In particular, when it is formed so as to straddle the hard part and the flexible part, the degree of freedom of the configuration of the wiring circuit (for example, the degree of freedom of selection of the terminal installation location) is increased.

  In addition, when conductor layers are provided on one surface side and the other surface side of the substrate, for example, the terminal of the element is connected to the optical waveguide forming substrate by electrically connecting predetermined portions of those conductor layers. Even in the case of being located inside, the conducting portion can be drawn out and energized to the outermost layer of the optical waveguide forming substrate, which increases the degree of freedom in circuit design.

  In addition, when the optical waveguide is formed inside each of the hard portion and the flexible portion, the optical waveguide can be effectively protected from dirt, scratches, deterioration, etc. while taking advantage of the above-mentioned advantages. Contributes to improved performance and longer life.

  In addition, the core portion selectively irradiates the active energy beam or electron beam to the core layer made of a material whose refractive index changes by irradiation with an active energy beam or electron beam or by further heating. If it is formed in a desired shape, the core portion can be patterned by a simple method of irradiation with an active energy ray or an electron beam, and a core portion with high dimensional accuracy can be obtained.

  When the core layer is composed of a resin composition containing a cyclic olefin resin, particularly a resin composition mainly composed of a norbornene resin, the difference in refractive index between the core portion and the clad portion should be increased. In addition, it has excellent heat resistance, and as a result, a high-performance optical waveguide can be obtained.

  As described above, it is possible to provide an optical waveguide forming substrate with good yield, high reliability, advantageous for thinning, a small installation space, and high versatility.

  Hereinafter, the optical waveguide forming substrate of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  1 to 22 are cross-sectional views schematically showing process examples of the method for manufacturing an optical waveguide forming substrate of the present invention. Among these, FIG. 22 is sectional drawing which shows embodiment of the optical waveguide formation board | substrate of this invention. Hereinafter, the configuration of the optical waveguide forming substrate and an example of the manufacturing method thereof will be described with reference to these drawings. In the following description, the upper side in FIGS. 8 to 22 is “upper” or “upper”, and the lower side is “lower” or “lower”. Each figure is exaggerated in the thickness direction of the layer (the vertical direction in each figure).

  As shown in FIG. 22, the optical waveguide forming substrate 17 has a hard portion (rigid portion) 171 and 173 having the hard substrates 2 and 12 and a flexible portion (between them) as viewed in the plane direction. Flexible portion) 175. When viewed in the plane direction, the hard portion 171 and the flexible portion 175 are adjacent to each other, and the flexible portion 175 and the hard portion 173 are adjacent to each other.

  The hard portion 171 includes the hard substrates 2 and 12, the insulating layers 6 and 10 formed on the inner sides thereof via the adhesive layers 7 and 14, respectively, and the conductor layers 5 and 11 ( Wirings 51 and 111), an optical waveguide 9 formed inside them, and conductor layers 3 and 13 (wirings 31, 33 and 131) formed on the outside of the substrates 2 and 12, respectively. Are joined.

  In the hard part 171, an element (element 1) composed of a light emitting element or a light receiving element is installed (mounted). Examples of the light emitting element include an element having at least one light emitting portion on the upper surface side and an element having at least one light emitting portion and at least one terminal on the upper surface side. Examples of the light receiving element include an element having at least one light receiving portion on the upper surface side, and an element having at least one light receiving portion and at least one terminal on the upper surface side.

  The light emitting portion in the light emitting element may be a single light emitting point or a plurality of light emitting points. As a set of a plurality of light emitting points, for example, the light emitting points are arranged in a row (for example, 1 × 4, 1 × 12) or in a matrix (for example, n × m: n, m And those in which a plurality of light emitting points are arranged randomly (irregularly). The same applies to the light receiving portion in the light receiving element.

In the present embodiment, a light-emitting element is typically described as the element 1.
In the element 1, a light emitting portion 101 and a terminal 103 are formed on the upper surface side in FIG. 22, and a terminal 105 is formed on the lower surface side. When the terminals 103 and 105 are energized, the light emitting unit 101 emits light. The thickness of the element 1 is usually thicker than the thickness of the substrate 2 described later. In this case, the element 1 is installed by being inserted into openings 25, 73 and 65 formed in the substrate 2, the adhesive layer 7 and the insulating layer 6, respectively. In the present invention, unlike the drawing, the light emitting portion 101 is provided on the upper surface side, but the element 1 without the terminal 103 may be used.

  The thickness of the element 1 is smaller than the thickness of the hard part 171 of the optical waveguide forming substrate 17, and the entire element 1 is located inside the hard part 171 (incorporated) and is hardly exposed on the surface. . In particular, the element 1 is installed such that the light emitting portion 101 is located inside the hard portion 171 and is not exposed on the surface. As a result, the entire element 1, in particular, the light emitting unit 101 is protected from dirt, damage, oxidation deterioration, and the like, and contributes to improving the reliability of the electronic component.

  The terminal 103 of the element 1 is electrically connected to a predetermined portion (wiring 51) of the conductor layer 5 by wire bonding with a metal wire 8. Further, the terminal 105 of the element 1 is electrically connected to a predetermined portion (wiring 31) of the conductor layer 3 by solder (brazing material) 4.

  The conductor layer 3 has a wiring 33 that is separated (insulated) from the wiring 31 connected to the terminal 105. The wiring 51 and the wiring 31 are electrically connected by a metal material (conductor post) 16 that penetrates the substrate 2, the adhesive layer 7, and the insulating layer 6.

  With the configuration as described above, current can be supplied to both terminals 103 and 105 of the element 1 by applying current between the wirings 33 and 31 exposed on the surface of the optical waveguide forming substrate 17.

  Since the configuration of the hard portion 173 can be substantially the same, the description thereof is omitted. In addition, the hard part 173 may not have the element 1, or the element 1 may be provided with a light receiving element (not shown) having a light receiving part. The hard portion 173 may constitute a connector (particularly an optical connector).

  The flexible portion 175 is obtained, for example, by removing the unnecessary portions 23 and 123 which are a part of the substrate 2 and the substrate 12, and the optical waveguide 9 and the wirings 51 and 111 are the insulating layers 6 and 10. A laminated structure having a structure sandwiched between them is formed. Accordingly, the flexible portion 175 has flexibility and can be bent and deformed. Due to the bending deformation of the flexible portion 175, the positional relationship between the hard portions 171 and 173 at both ends thereof can be changed. As a result, the applicable range, shape, and installation location of the optical waveguide forming substrate 17 In addition, the degree of freedom in designing the installation posture and the like is expanded, and the positioning accuracy during installation is relaxed. Further, one of the hard parts 171 and 173 can be installed in a fixed part (for example, a main body part) of the electronic apparatus, and the other can be installed in a movable part (for example, a slide part).

  The optical waveguide 9 is formed across the hard part 171, the flexible part 175, and the hard part 173. Thereby, the freedom degree of the design of the circuit pattern of the optical circuit by the optical waveguide 9 spreads, and the application range to various electronic components and apparatuses expands.

  The optical waveguide 9 is formed by laminating a clad layer 91, a core layer 93, and a clad layer 97 in this order from the lower side in FIG. 22. The core layer 93 includes a core portion 94 and a clad portion 95 having a predetermined pattern. Is formed. The core portion 94 is formed in a pattern shape that overlaps with the light emitting portion 101 in a plan view (that is, passes directly above the light emitting portion 101). The core portion 94 is made of a material having a higher refractive index than that of the cladding portion 95, and is made of a material having a higher refractive index than the cladding layers 91 and 97. The clad layers 91 and 97 constitute the clad portions located below and above the core portion 94, respectively. With such a configuration, the core portion 94 functions as a light guide path whose outer periphery is surrounded by the cladding portion.

  The constituent materials of the clad layer 91, the clad portion 95, and the clad layer 97 may be the same (same type) or different, but these have the same or similar refractive index. Is preferred. Details of the constituent materials of the cladding layers 91 and 97 and the core layer 93 will be described later.

  Such an optical waveguide 9 has a reflective surface 96 at a position directly above the light emitting portion 101 of the core portion 94. The reflection surface 96 is inclined by approximately 45 ° with respect to the optical path of the optical waveguide 9, that is, the longitudinal direction of the core portion 94.

  The optical waveguide 9 is formed inside each of the hard portion 171 and the flexible portion 175. That is, the optical waveguide 9 is protected not only in the hard portion 171 but also in the flexible portion 175 by the insulating layers 6 and 10, so that it is possible to prevent dirt, damage, alteration, deterioration, and the like. This contributes to improved reliability and longer life.

  In the optical waveguide forming substrate 17 of the present embodiment, as described above, the energization to the both terminals 103 and 105 of the element 1 (lighting of the light emitting unit 101) is arranged alongside the lower surface of the optical waveguide forming substrate 17, respectively. This can be done by energization between 31 and 33. When power is applied between the terminals 103 and 105 of the element 1, the light emitting unit 101 is turned on, and the light emitted upward in FIG. 22 is reflected by the reflecting surface 96 and bent by 90 °. It enters the core portion 94 and proceeds along the longitudinal direction in the core portion 94 while repeating reflection at the interface with the cladding portions (cladding layers 91 and 97, cladding portion 95).

  In the illustrated optical waveguide forming substrate 17, the optical waveguide 9 is formed across the hard portion 171, the flexible portion 175, and the hard portion 173, and most of the portions are the hard portion 171 and the possible portion. It is formed inside the flexible part 175 and the hard part 173. Therefore, the optical waveguide 9 is excellent in durability and stability of characteristics, and contributes to improvement in reliability and life of electronic components. In particular, even when the flexible portion 175 is bent and deformed (particularly when it is repeatedly bent and deformed many times), the optical waveguide 9 is not damaged or deteriorated, and the light guide characteristics are not adversely affected.

  Further, at least one of the conductor layers 5, 11 and 13 (wirings 51, 111, 131) is formed across the hard portion 171 and the flexible portion 175. Thereby, the freedom degree of the design of the wiring pattern in an electric circuit spreads, and the application range to various electronic components and apparatuses expands. In particular, as described above, the degree of freedom in design is greatly expanded in combination with the increase in the degree of freedom in designing the optical circuit.

Next, an example of a method for manufacturing the optical waveguide forming substrate 17 will be described.
[1] First, a jig (workbench) 18 for incorporating the element 1 into the substrate 2 is prepared. As shown in FIG. 1, the jig 18 has a substrate abutting surface 180, and a concave portion 181 and a convex portion 183 into which the element 1 can be inserted are formed on the substrate abutting surface 180 side.

The element 1 is inserted into the recess 181 so that the upper surface side of the element 1 (the side where the light emitting unit 101 and the terminal 103 are located) is in contact with the bottom surface of the recess 181 (see FIG. 2). The planar shape of the recess 181 is substantially the same as the planar shape of the element 1, and the depth of the recess 181 is set to a predetermined value that is slightly shallower than the thickness of the element 1. Thereby, the positioning of the element 1 in the planar direction and the thickness direction with respect to the substrate 2 is appropriately performed in a process described later. In a state where the element 1 is inserted into the recess 181, the lower surface side of the element 1 protrudes above the substrate abutting surface 180.
A solder paste 4 ′ is applied on the terminal 105 on the lower surface of the element 1.

[2] An uncured substrate 2 'is prepared. In the substrate 2 ′, an opening 25 having a shape corresponding to the element 1 and grooves 21 and 21 corresponding to the convex portions 183 and 183 are formed (see FIG. 2). A portion between the grooves 21 and 21 constitutes an unnecessary portion (removal portion) 23 to be removed later.

  The substrate 2 ′ is applied to the substrate application surface 180 of the jig 18. At this time, the portion on the lower surface side of the element 1 is inserted into the opening 25 of the substrate 2 ′, and the convex portion 183 corresponding to each groove 21 is inserted (see FIG. 3). Thereby, the positioning of the element 1 with respect to the substrate 2 ′ in the three-dimensional direction, that is, the planar direction (two orthogonal directions on the plane) and the thickness direction is appropriately performed. The lower surface of the substrate 2 '(the upper surface in FIG. 3) and the lower surface of the element 1 do not coincide with each other, and have a slight gap corresponding to the thickness of the solder 4 described later. Solder 4 is inserted into this gap.

[3] Next, the conductor layer 3 is formed (bonded) on the lower surface (the upper surface in FIG. 3) of the substrate 2 '. Examples of the method for forming the conductor layer 3 include methods such as metal foil bonding (adhesion) and metal plating. Examples of the material constituting the conductor layer 3 include various metal materials such as copper, a copper-based alloy, aluminum, and an aluminum-based alloy. Although the thickness of the conductor layer 3 is not specifically limited, Usually, about 3-100 micrometers is preferable and about 5-70 micrometers is more preferable.

  In the present invention, after the conductor layer 3 is formed, the conductor layer 3 may be subjected to predetermined patterning to form a wiring having a desired shape.

[4] Next, heat treatment is performed to thermally cure the substrate 2 ′ to obtain a hard substrate (after curing) 2. Further, by this heat treatment, the solder paste 4 'is melted, and the terminal 105 of the element is electrically connected to a predetermined portion of the conductor layer 3 through the solder (brazing material) 4 (see FIG. 3).

  Examples of the constituent material of the substrate 2 include epoxy resins, phenol resins, bismaleimide resins, bismaleimide / triazine resins, triazole resins, polycyanurate resins, polyisocyanurate resins, and benzocyclobutene resins. These materials may be used alone or in combination.

  Although the thickness of the board | substrate 2 is not specifically limited, Usually, about 50-1000 micrometers is preferable and about 100-500 micrometers is more preferable.

  The conditions for the heat treatment are appropriately determined depending on the constituent material of the substrate 2 and the like, but are usually preferably about 80 to 300 ° C. for about 10 to 180 minutes, and more preferably about 120 to 260 ° C. for about 60 to 120 minutes.

  When the above operation is completed, the jig 18 is removed (see FIG. 4). Thus, the element 1 is fixed to the opening 25 of the substrate 2 on which the conductor layer 3 is formed on the lower surface side so that the upper surface side protrudes from the opening 25, and the terminal 105 of the element 1 and the predetermined portion of the conductor layer 3 are Can be obtained.

  In order to improve the releasability between the jig 18 and the substrate 2 when the jig 18 is removed, a release sheet such as an aluminum foil that has been subjected to a release treatment is previously installed on the jig 18. Also good.

[5] On the other hand, a material obtained by joining the insulating layer 6 and the conductor layer 5 is prepared (see FIG. 5). The conductor layer 5 is disposed on the upper surface side of the substrate 2 through a subsequent process. In addition to having an insulating function with respect to the conductor layer 5, the insulating layer 6 bears its strength when a flexible portion 175 described later is formed. Moreover, it also has a function of protecting the lower surface side of the optical waveguide 9 formed later.

  As the insulating layer 6, for example, a flexible resin film (sheet material) can be used. Examples of the constituent material thereof include polyamide, polyimide, polyamideimide, polyetherimide, polyesterimide, and polyethylene. Polyester such as terephthalate, polyetheretherketone, polyethylene sulfide, polyphenylene sulfide, polyquinoline, polynorbornene, polybenzoxazole, polybenzimidazole, epoxy resin, phenol resin, bismaleimide resin, bismaleimide / triazine resin, triazole resin, polystyrene Annulates, polyisocyanurates, benzocyclobutene resins and the like can be mentioned. These materials may be used alone or in combination. The insulating layer 6 may be a laminate in which a plurality of resin material layers having different compositions are laminated.

  The thickness of the insulating layer 6 is not particularly limited, but is preferably about 5 to 100 μm and more preferably about 10 to 80 μm in view of the insulating function and strength.

  The conductor layer 5 can be the same as that of the conductor layer 3 described above, and the preferable formation method, constituent material, thickness, and the like are the same.

[6] Predetermined patterning is performed on the insulating layer 6 (see FIG. 6). Although the method is not particularly limited, for example, the groove 61 is formed by laser light irradiation, and the inside thereof is removed as an unnecessary portion (removal portion) 63 to form an opening 65 into which the element 1 can be inserted (FIGS. 6 and 6). 7). The opening 65 has a shape substantially equal to or including the opening 25 of the substrate.

  The conductor layer 5 is subjected to predetermined patterning to form a wiring 51 having a desired shape. This patterning can be performed by etching, for example.

  In addition, by this patterning, the removal portion 53 is formed together with the formation of the wiring 51 in the portion corresponding to the opening 65 of the conductor layer 5. The removal portion 53 is formed in a region including the opening 65, and the edge of the removal portion 53 is located outside the edge of the opening 65 (see FIG. 7). This prevents the conductor layer 5 from coming into direct contact with the element 1 (see FIG. 9) and prevents the possibility of a short circuit or the like.

  Note that the lamination of the insulating layer 6 and the conductor layer 5, the patterning of the insulating layer 6, and the patterning of the conductor layer 5 are not limited to the order described above, and those shown in FIG. 7 can be obtained in an arbitrary order. For example, a method may be used in which the conductor layer 5 is formed on the insulating layer 6 patterned in advance, and the conductor layer 5 is patterned to form the wiring 51.

[7] An adhesive layer 7 is prepared. This adhesive layer 7 adheres the substrate 2 and the insulating layer 6, and is formed with an opening 71 having a shape corresponding to the groove 21 and the unnecessary portion 23 of the substrate 2 and an opening 73 into which the element 1 can be inserted. (See FIG. 8). The opening 73 has a shape substantially equal to or including the opening 25 of the substrate.

  As the adhesive layer 7, a sheet material (bonding sheet) can be used, and examples of the constituent material thereof include an epoxy adhesive, an acrylic adhesive, a phenol resin adhesive, a cyanate resin adhesive, and a maleimide resin. System adhesives and the like. In particular, it is preferably made of a material having flux activity for preventing oxidation or the like.

  In the present invention, the adhesive layer 7 may be formed on the upper surface of the substrate 2 or the lower surface of the insulating layer 6 without using a sheet material as the adhesive layer 7. The adhesive layer 7 may be a laminate of two or more layers.

  The thickness of the adhesive layer 7 is not particularly limited, but is preferably about 0.5 to 150 μm, and more preferably about 10 to 70 μm.

[8] The substrate 2 on which the element 1 obtained in the step [4] is mounted is placed so that the light emitting portion 101 of the element 1 faces upward, and the adhesive layer 7 and the wiring 51 are formed thereon. The insulating layer 6 and the release film (release film) 19 are sequentially stacked (see FIG. 8). At this time, the protruding portion from the opening 25 of the element 1 is inserted into the opening 73 of the adhesive layer 7 and the opening of the insulating layer 6, and the adhesive layer 7 and the insulating layer 6 are aligned with respect to the substrate 2 in the planar direction.

  The release film 19 is used to press uniformly in the surface direction when pressurizing in the next step. Therefore, the constituent material of the release film 19 has a buffer function (cushioning property). Is preferred. Furthermore, the thing excellent in the embedding property with respect to the site | part (conductor layer 5 comprised with the wiring 51) and mold release property is preferable.

  As such a release film 19, one having a buffer layer and a release layer bonded to the lower surface side of the buffer layer and press-bonded to the conductor layer 5 is preferable. Examples of the constituent material of the buffer layer include polyolefins such as polyethylene and polypropylene, and examples of the constituent material of the release layer include polymethylpentene copolymer.

[9] As indicated by an arrow in FIG. 9, the substrate 2, the adhesive layer 7, and the insulating layer 6 with the wiring 51 are pressure bonded by pressing from the upper surface side of the release film 19. Thereby, the board | substrate 2 and the insulating layer 6 with the wiring 51 are joined and integrated via the contact bonding layer 7. FIG. This crimping operation is preferably performed under heating. The heating temperature is appropriately determined depending on the constituent material of the adhesive layer 7 and the like, but is usually preferably 80 to 200 ° C, more preferably 120 to 180 ° C.

[10] The release film 19 is peeled off and removed. Thereby, the board | substrate 2 which has the conductor layer 3 and the conductor layer 5 (wiring 51) in the lowermost layer and the uppermost layer, respectively, and mounted the element 1 is obtained (refer FIG. 10). In this case, as shown in FIG. 10, the upper surface of the conductor layer 5 (wiring 51) forms substantially the same surface as the upper surface of the element 1, that is, the upper surfaces of the conductor layer 5 and the element 1 are in the thickness direction. (The difference in height is, for example, 10 μm or less). The reason will be described in the next step.

  In order to make the upper surface of the conductor layer 5 (wiring 51) and the upper surface of the element 1 substantially the same plane, the thickness of the conductor layer 5, the material of the insulating layer 6 (degree of shrinkage due to pressure bonding), the number of layers, the thickness, The material of the adhesive layer 7 (degree of shrinkage due to pressure bonding), the number of layers, thickness, pressing conditions, heating conditions, and other conditions are appropriately selected, and the conductor layer 5 after the pressure bonding process (step [9]), insulation The total thickness of the layer 6 and the adhesive layer 7 may be substantially equal to the height (thickness) H of the protruding portion from the opening 25 of the element 1.

[11] The terminal 103 on the upper surface side of the element 1 is electrically connected to a predetermined part of the wiring 51. This method is preferably performed by wire bonding with a metal wire 8 (see FIG. 11). This is because the work efficiency of electrical connection is good, disconnection, etc. are extremely small and the reliability is high.

  In the electrical connection work represented by this wire bonding, as described above, the upper surface of the conductor layer 5 (wiring 51) and the upper surface of the element 1 form substantially the same surface, so that the work is easier and more reliable. It can be performed and can be connected (connected) without causing a step (height difference) at both ends of the wire 8, so that the length of the wire 8 can be further shortened.

  Also, even when the wire 8 protrudes upward in a mountain shape, its height can be made as small as possible, so that the space for the connecting portion can be reduced and also contributes to prevention of disconnection. Furthermore, the optical waveguide 9 formed thereon can be formed in a flat shape, and the thickness thereof can be made as thin as possible.

[12] Next, the optical waveguide 9 is formed on the upper surface side of the substrate 2 on which the element 1 obtained in the step [11] is mounted, that is, on the upper surface of the wiring 51 and the element 1. The optical waveguide 9 has a core portion and a clad portion having different refractive indexes, and is formed through a plurality of steps described below. Hereinafter, the steps will be sequentially described.

  First, a clad layer (lower clad layer) 91 is formed on the upper surfaces of the wiring 51 and the element 1 (see FIG. 12). As a forming method of the clad layer 91, a method of bonding a separately manufactured sheet material, a method of applying and curing (solidifying) a resin composition (varnish or the like) containing a clad material (cladding portion forming material), curability Any method may be used, such as a method of applying and curing (solidifying) a monomer composition having the above.

  Examples of the constituent material of the clad layer 91 include acrylic resin, methacrylic resin, polycarbonate, polystyrene, epoxy resin, polyamide, polyimide, polybenzoxazole, polysilane, polysilazane, benzocyclobutene resin, norbornene resin, and the like. These can be used in combination of one or more of them (polymer alloy, polymer blend (mixture), copolymer, composite (laminate), etc.).

  Among these, epoxy resins, polyimides, polybenzoxazoles, polysilanes, polysilazanes, cyclic olefin resins such as benzocyclobutene resins and norbornene resins, or those containing them (mainly in terms of excellent heat resistance) Are preferably used).

  Examples of the cyclic olefin resin include cycloaddition polymers of unsaturated olefin derivatives, (co) polymers of cyclic olefin monomers, and copolymers of cyclic olefin monomers with other copolymerizable monomers such as α-olefins. Examples thereof include polymers and hydrogenated products of these copolymers. Examples of these polymers include random copolymers, block copolymers, and alternating copolymers. These cyclic olefin-based resins can be produced by a known polymerization method, and examples of the polymerization method include an addition polymerization method and a ring-opening polymerization method. Of these, polymers obtained by polymerizing norbornene monomers (particularly addition (co) polymerization) are preferred. This is preferable because it is rich in transparency and flexibility. However, the present invention is not limited to this.

  Examples of the addition polymer of the cyclic olefin resin include (1) addition (co) polymer of norbornene type monomer obtained by addition (co) polymerization of norbornene type monomer, (2) norbornene type monomer and ethylene, Examples include addition copolymers with α-olefins, (3) addition copolymers with norbornene-type monomers and non-conjugated dienes, and other monomers as necessary. These resins can be obtained by all known polymerization methods.

  Examples of the ring-opening polymer of the cyclic olefin-based resin include, for example, (4) a ring-opening (co) polymer of a norbornene-type monomer, and a resin obtained by hydrogenating the (co) polymer if necessary, ( 5) Ring-opening copolymer of norbornene-type monomer and ethylene or α-olefin, and a resin obtained by hydrogenating the (co) polymer if necessary, (6) Norbornene-type monomer and non-conjugated diene, or others And a resin obtained by hydrogenating the (co) polymer if necessary. These resins can be obtained by all known polymerization methods.

  When the clad layer 91 is formed by a coating method, examples thereof include a spin coating method, a dipping method, a table coating method, a spray method, an applicator method, a curtain coating method, and a die coating method. The same applies to the formation of the cladding layer 97 described later.

[13] Next, the core layer 93 is formed on the cladding layer 91 (see FIG. 13). As a method of forming the core layer 93, for example, a method of joining separately manufactured sheet materials, a method of applying and curing (solidifying) a resin composition (such as a varnish) containing a core material (core portion forming material), The method of apply | coating and hardening (solidifying) the monomer composition which has curability is mentioned.

  Examples of the constituent material of the core layer 93 include acrylic resin, methacrylic resin, polycarbonate, polystyrene, epoxy resin, polyamide, polyimide, polybenzoxazole, polysilane, polysilazane, benzocyclobutene resin, norbornene resin, and the like. The cyclic olefin resin is preferably made of a material whose refractive index changes upon irradiation with active energy rays or electron beams (or by further heating).

  Preferred examples of such materials are obtained by addition (co) polymerization of silane resins such as polysilane (eg, polymethylphenylsilane), polysilazane (eg, perhydropolysilazane), and (1) norbornene type monomers. Norbornene-type monomer addition (co) polymers, (2) norbornene-type monomers and addition copolymers of ethylene and α-olefins, (3) norbornene-type monomers and non-conjugated dienes, and other Addition copolymer with monomer, (4) ring-opening (co) polymer of norbornene-type monomer, and resin obtained by hydrogenation of (co) polymer if necessary, (5) norbornene-type monomer and ethylene or α -Ring-opening copolymer with olefins, and a resin obtained by hydrogenating the (co) polymer as necessary, (6) Non-conjugated with norbornene-type monomer It is obtained by polymerizing a ring-opening copolymer with a diene or another monomer, and a norbornene resin such as a resin obtained by hydrogenating the (co) polymer, if necessary, or other photo-curing reactive monomers. An acrylic resin, an epoxy resin, etc. are mentioned, but among these, a norbornene resin is particularly preferable.

  When the core layer 93 is formed by a coating method, for example, a spin coating method, a dipping method, a table coating method, a spray method, an applicator method, a curtain coating method, a die coating method, and the like can be given.

[14] The core layer 93 obtained in the previous step is selectively irradiated with an active energy ray or an electron beam from above in FIG. 14 using the mask 20 to pattern the core portion 94 having a desired shape. The core portion 94 is formed in a pattern shape that overlaps with the light emitting portion 101 in a plan view (preferably including the light emitting portion 101).

  An opening (window) 201 equivalent to the pattern of the core portion 94 to be formed is formed in the mask 20 (see FIG. 14). This opening 201 forms a transmission part through which the active energy beam or electron beam to be irradiated passes.

  The mask 20 may be formed in advance (separately formed) (for example, plate-shaped) or may be formed on the core layer 93 by, for example, a vapor deposition method or a coating method. Preferred examples of the mask 20 include a photomask made of quartz glass or a PET base material, a stencil mask, a metal thin film formed by a vapor deposition method (evaporation, sputtering, etc.), etc. Among these, it is particularly preferable to use a photomask or a stencil mask. This is because a fine pattern can be formed with high accuracy, and handling is easy, which is advantageous in improving productivity.

  Further, in FIG. 14, the opening (window) 201 equivalent to the pattern of the core portion 94 to be formed is shown by partially removing the mask along the pattern of the light irradiation portion. In the case of using a photomask made of a PET substrate or the like, it is also possible to use a photomask provided with an active energy ray or electron beam shielding portion made of a shielding material made of metal such as chromium. In this mask, the part other than the shielding part is the window (transmission part).

  Examples of the active energy ray used for exposure include visible light, ultraviolet light, infrared light, and laser light. Moreover, an electron beam can be irradiated with the irradiation amount of about 50-2000KGy, for example.

  The constituent material of the mask 20 is appropriately selected depending on the active energy ray or electron beam to be irradiated. When irradiating an active energy beam, it is a material that can block the active energy beam, and when irradiating an electron beam, it is a material that blocks the electron beam. As long as it has such characteristics, any known material can be used for the mask 20 itself.

  In the core layer 93, the refractive index of the portion irradiated with the active energy beam or the electron beam changes (the refractive index may increase or decrease depending on the material of the core layer 93), and the active energy beam. Alternatively, a difference in refractive index is generated between the portion not irradiated with the electron beam. In the example shown in FIG. 14, the portion (indicated by the dotted line in FIG. 14) irradiated with the active energy ray or the electron beam of the core layer 93 is the core portion 94, and the portion not irradiated is the cladding portion 95. The refractive index of the cladding part 95 is substantially equal to the refractive index of the cladding layer 91 and a cladding layer 97 described later.

  The difference in refractive index between the core portion 94 and the clad portion 95 is not particularly limited, but is preferably about 0.3 to 5.5%, and particularly preferably about 0.8 to 2.2%. If the difference in refractive index is less than the lower limit, the effect of transmitting light may be reduced. If the upper limit is exceeded, there is a large possibility that the decomposition reaction due to electron beam irradiation has occurred excessively, Stability may be reduced (however, this problem does not occur in the case of irradiation with active energy rays).

The refractive index difference is expressed by the following equation, where A is the refractive index of the core portion 94 and B is the refractive index of the cladding portion 95.
Refractive index difference (%) = | A / B-1 | × 100
In this step, positioning of the active energy ray or electron beam irradiation site in the core layer 93, that is, alignment of the mask 20 with respect to the substrate 2 on which the element 1 is mounted having the clad layer 91 as the uppermost layer is performed. It is preferable that at least one of 101 and terminal 103 is used as an index. Thereby, accurate alignment can be easily performed, and highly accurate patterning can be performed in a short work time.

  For this alignment, for example, the position of the light emitting unit 101 and / or the terminal 103 of the element 1 is grasped by a CCD camera, and the position (relative) of the mask 20 with respect to the substrate 2 on which the element 1 is mounted with this position as a reference (index) This is done by determining the general positional relationship).

  An example of the positioning method will be described in more detail. The mask 20 is fixed and a CCD camera (not shown) capable of imaging the element 1 is fixed above the mask 20, while the substrate 2 on which the element 1 is mounted is placed on, for example, an XY stage. Alternatively, the element 1 is supported so that the robot can move in the X direction and the Y direction in FIG. 14, and the position A of the opening 201 coincides with the position of the light emitting unit 101 captured and captured (stored) by the CCD camera. The mounted substrate 2 is appropriately moved and fixed in a two-dimensional direction (X direction, Y direction and rotation (θ) direction). Of course, the substrate 2 on which the element 1 is mounted may be fixed and the mask 20 side may be moved, or both may be moved (for example, the substrate 2 on which the element 1 is mounted moves in the X direction, 20 moves in the Y direction).

  As described above, when alignment is performed with the light emitting unit 101 as a reference, alignment is performed such that a predetermined portion of the opening 201 (portion where the core portion 94 is to be formed) of the mask 20 overlaps the light emitting unit 101 in the surface direction. However, it is also possible to perform alignment with the terminal 103 as a reference. That is, since the positional relationship between the light emitting portion 101 and the terminal 103 is unique to the element 1 and is known, the position of the terminal 103 is used as a reference, and the predetermined portion (location) of the opening 201 of the mask 20 is the same as described above. A) The substrate 2 on which the element 1 is mounted is moved relative to the mask 20 in a two-dimensional direction (X direction, Y direction, and rotation (θ) direction) so that the light emitting unit 101 and A) overlap each other. be able to.

  Further, the same alignment can be performed using both the light emitting unit 101 and the terminal 103 (two points) as a reference. In this case, since it is possible to perform alignment by specifying two points on the plane, for example, it is possible to correct a shift such as rotation of the substrate 2 on which the element 1 is mounted with respect to the mask 20, and more accurate position. Matching is possible.

  Further, the alignment may be performed using one or more other points as reference points. When a plurality of elements 1 are mounted on the substrate 2, that is, for example, when one or more sets of light emitting elements and light receiving elements are mounted, the light emitting portion (or terminal) of one element and the other one element Alignment can be performed using the light receiving part (or terminal) of the optical fiber as an index (reference point). In this case, each reference point is formed on a different element, and they are separated by a considerable distance, so that more accurate alignment can be performed.

  Here, when alignment is performed with the light emitting unit 101 as a reference, a part of the light emitting unit 101 (for example, when the light emitting unit 101 has a plurality of light emitting points), the light emitting unit 101 is used as a reference. The light emission point) may be used as a reference.

  As another method, the core portion 94 may be formed by directly irradiating the core layer 93 with active energy rays (or electron beams) having good directivity such as laser light without using the mask 20. . Even in this case, for the setting of the irradiation position, the alignment method as described above, that is, the alignment can be performed with reference to the light emitting unit 101 and / or the terminal 103, and the same effects as described above can be obtained.

  Alternatively, the core portion 94 may be formed by irradiating the core layer 93 with an active energy ray or an electron beam in a predetermined pattern and heating. For example, when the above-described norbornene-based resin is used as the main material of the core layer 93, polymerization is promoted in the constituent material of the core layer 93 by adding this heating step, and the refraction between the core portion 94 and the cladding portion 95 is performed. This is preferable because the difference in rate becomes larger. The temperature of heating can be about 40-160 degreeC, for example.

  The core portion 94 may be formed by a normal photolithography method. That is, a resist layer may be formed, the pattern of the core part 94 may be exposed and developed, and the developed part (concave part) may be filled with a material constituting the core part 94 to form the core part 94. Even in this case, for the setting of the light irradiation position at the time of exposure, the alignment method as described above, that is, the alignment can be performed with reference to the light emitting unit 101 and / or the terminal 103, and the same as described above. There is an effect.

  The pattern shape of the core portion 94 to be formed is not particularly limited, and is linear, a shape having a curved portion, a shape having a branching portion or a crossing portion, a light collecting portion (a portion where the width or the like is reduced) or light. Any of a diffusion part (a part where the width or the like is increased) or a combination of two or more of these may be used.

  In the above description, the case where the core layer 93 is irradiated with an active energy ray or an electron beam in a desired pattern using the mask 20 and the irradiated portion is used as the core portion 94 has been described. Using a mask having an opening (window) equivalent to the cladding portion 95 to be formed or a mask having at least a shielding portion equivalent to the core portion 94 to be formed, an active energy ray or an electron beam is irradiated in a desired pattern. Then, the core portion 94 (the portion that is not irradiated) may be formed by using the irradiated portion as the cladding portion 95. Even in this case, alignment can be performed by the same alignment method as described above.

[15] When the core portion 94 is formed in the core layer 93 as described above, the reflective surface 96 is formed at a position directly above the light emitting portion 101 of the core portion 94 (see FIG. 15). The reflecting surface 96 is inclined by approximately 45 ° with respect to the optical path of the optical waveguide, that is, the longitudinal direction of the core portion 94.

  Examples of the method for forming the reflecting surface 96 include a method in which the clad layer 91 and the core layer 93 are partially removed by cutting, laser light irradiation, or the like.

  Even when the reflective surface 96 is formed, the alignment can be performed using the light emitting unit 101 and / or the terminal 103 as a reference (index).

[16] Prepare a material obtained by bonding the insulating layer (flexible resin layer) 10 and the conductor layer 11 (see FIG. 16). In addition to having an insulating function with respect to the conductor layer 11, the insulating layer 10 bears its strength when a flexible portion 175 described later is formed. Also, it has a function of protecting the upper surface side of the optical waveguide 9.

  The conditions such as the constituent material, the layer configuration, and the thickness of the insulating layer 10 are the same as those of the insulating layer 6. The conductor layer 11 can also be the same as the conductor layers 3 and 5 described above, and the preferable formation method, constituent material, thickness, and the like are the same as those.

[17] The conductor layer 11 is subjected to predetermined patterning to form a wiring 111 having a desired shape (see FIG. 17). This patterning can be performed by a method such as etching or printing.

[18] A cladding layer (upper cladding layer) 97 is formed on the lower surface of the insulating layer 10 on which the wiring 111 is formed (see FIG. 18). As a method for forming the clad layer 97, a method of bonding a separately manufactured sheet material, a method of applying and curing (solidifying) a resin composition (varnish or the like) containing a clad material (clad portion forming material), and curability Any method may be used, such as a method of applying and curing (solidifying) a monomer composition having the above.

  Examples of the constituent material of the clad layer 97 include the same materials as those mentioned for the clad layer 91, and the same applies to preferable materials among them.

[19] A cured substrate (hard resin layer) 12 having a conductor layer 13 formed (bonded) on the upper surface is prepared (see FIG. 19). The conductor layer 13 can be the same as the conductor layers 3 and 5 described above, and the preferable formation method, constituent material, thickness, and the like are the same as those. Grooves 121, 121 are formed in the substrate 12, and a portion between the grooves 121, 121 constitutes an unnecessary part (removal part) 123 to be removed later.

  The substrate 12 may be cured or uncured, but in the latter case, it is cured by heating until the joining step shown in FIG.

[20] The adhesive layer 14 is prepared. The adhesive layer 14 is for bonding the substrate 12 and the insulating layer 10, and has an opening 141 having a shape corresponding to the groove 121 and the unnecessary portion 123 of the substrate 12 (see FIG. 19).
The form, constituent material, thickness, and the like of the adhesive layer 14 are the same as those of the adhesive layer 7.

[21] As shown in FIG. 19, the laminated body of the cladding layer 97, the wiring 111 and the insulating layer 10 obtained in the step [18] is overlaid on the core layer 93 of the substrate 2 on which the element 1 is mounted. The adhesive layer 14 is overlaid thereon, and the laminate of the substrate 12 and the conductor layer 13 is further overlaid thereon. At this time, alignment is performed so that the groove 21 and the unnecessary portion 23 of the substrate 2, the opening 141 of the adhesive layer 14, and the groove 121 and the unnecessary portion 123 of the substrate 12 coincide in the plane direction.

[22] In FIG. 20, the stacked substrate 2 on which the element 1 is mounted, the laminate of the cladding layer 97, the wiring 111 and the insulating layer 10, the adhesive layer 14, and the laminate of the substrate 12 and the conductor layer 13 As indicated by the arrow, pressure is applied from the upper surface side of the conductor layer 13 and these are pressure-bonded. This crimping operation is preferably performed under heating. The heating temperature is appropriately determined depending on the constituent materials of the core layer 93, the clad layer 97, and the adhesive layer 14, and is usually preferably 80 to 200 ° C and more preferably 120 to 180 ° C.

  The bonded body 17 ′ is obtained by the pressure bonding operation as described above. That is, the core layer 93 and the clad layer 97 are joined to obtain the optical waveguide 9 in which the core layer 93 is interposed between the clad layers 91 and 97, and the insulating layer 10 and the substrate are interposed via the adhesive layer 14. The upper reinforcement part joined with 12 is formed.

  In this joined body 17 ′, the optical waveguide 9 and the element 1 are both positioned between the hard substrates 2 and 12, are not exposed on the surface, and are built in the joined body 17 ′ (see FIG. 20 to 22). Therefore, the thickness of the entire bonded body can be reduced, and damage due to exposure to the surface is prevented, contributing to improvement of the reliability of the electronic component.

[23] Next, a via hole 15 is formed at a predetermined position of the joined body 17 '(see FIG. 21). In the illustrated example, the via hole 15 is for electrically connecting the wiring 51 and the conductor layer 3 (wiring 33 described later).

  Examples of the method for forming the via hole 15 include drilling with a drill and laser light irradiation.

  The formation position, formation pattern, formation method and the like of the via hole 15 are not particularly limited. For example, a via hole penetrating the optical waveguide 9 may be provided, or a via hole penetrating the entire joined body 17 ′ may be provided.

[24] Next, the conductor layers 3 and 13 formed on both surfaces of the joined body 17 ′ are respectively subjected to predetermined patterning to form wirings 31 and 131 having desired shapes (see FIG. 22). ). At this time, a wiring 33 separated (insulated) from the wiring 31 connected to the terminal 105 is formed.

  The patterning on the conductor layers 3 and 13 can be performed by the same method as the patterning on the conductor layers 5 and 11.

  Further, by this patterning, the portions supporting the unnecessary portions 23 and 123 of the conductor layers 3 and 13 are removed, and as a result, the unnecessary portions 23 and 123 are separated and removed.

[25] The via hole 15 is filled with the metal material 16. Thereby, predetermined portions of the wiring 51 and the wiring 33 are electrically connected to each other (see FIG. 22). The filling method of the metal material 16 is not specifically limited, For example, it can carry out by methods, such as metal plating, filling of a metal paste or nano metal ink, and a heating.
As described above, the optical waveguide forming substrate 17 of the present invention is completed.

  In the present invention, it goes without saying that the structure, layer configuration, shape, number, arrangement, and the like of the hard part and the flexible part are not limited to those shown in the drawings. For example, the hard substrate installed in the hard portion may have a structure that does not have the upper substrate 12 but has only the substrate 2, particularly the substrate 2 from which the unnecessary unnecessary portion 23 is removed. Furthermore, the flexible part may be formed at two or more places, or may be formed in a relatively wide area.

  Further, the manufacturing method of the optical waveguide forming substrate is not limited to the above-described one. For example, in the above description, the unnecessary portions 23 and 123 are removed later to form the flexible portion 175. However, the substrates 2 and 12 are installed in places other than the flexible portion 175, and the hard portion and the flexible portion You may employ | adopt the method of forming.

  In the above-described embodiment, the light emitting element is described as a representative example of the element 1, but a light receiving element having a light receiving portion may be used. In this case, instead of the light emitting unit 101, the light guide formed by the core unit 94 may be guided to the light receiving unit.

  Further, the optical waveguide forming substrate may have at least one set of both the light emitting element and the light receiving element. For example, a configuration in which a light emitting element and a light receiving element are installed in each of the hard parts 171 and 173, and the light emitting part and the light receiving part are connected by an optical path of an optical waveguide. Further, it is sufficient that at least one (preferably both) of the light emitting element and the light receiving element satisfies the above-described requirements.

  As described above, the present invention has been described based on the illustrated embodiments, but the present invention is not limited to these, and the configuration of each part can be replaced with any configuration that can exhibit the same function, In addition, an arbitrary configuration may be added.

It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is a perspective view (partial sectional view) showing typically an example of a process of a manufacturing method of an optical waveguide formation board of the present invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically the process example of the manufacturing method of the optical waveguide formation board | substrate of this invention. It is sectional drawing which shows typically embodiment of the optical waveguide formation board | substrate of this invention.

Explanation of symbols

1 element (light emitting element or light receiving element)
101 Light emitting part (light receiving part)
103 terminal 105 terminal 2 'substrate (uncured)
2 Substrate (after curing)
21 Groove 23 Unnecessary part (removal part)
25 opening 3 conductor layer 31 wiring 33 wiring 4 'solder paste 4 solder 5 conductor layer 51 wiring 53 removal part 6 insulating layer 61 groove 63 unnecessary part (removal part)
65 Opening 7 Adhesive layer 71 Opening 73 Opening 8 Wire 9 Optical waveguide 91 Cladding layer 93 Core layer 94 Core part 95 Cladding part 96 Reflecting surface 97 Cladding layer 10 Insulating layer 11 Conductive layer 111 Wiring 12 Substrate 121 Groove 123 Unnecessary part (removed part) )
13 Conductor 131 Wiring 14 Adhesive Layer 141 Opening 15 Via Hole 16 Metal Material 17 ′ Joint 17 Optical Waveguide Forming Substrate 171 Hard Portion (Rigid Portion)
173 Hard part (rigid part)
175 Flexible part (flexible part)
18 Jig 180 Substrate abutting surface 181 Concave part 183 Convex part 19 Release film 20 Mask 201 Opening

Claims (13)

An optical waveguide forming substrate having a plate shape ,
An optical waveguide composed of a core layer having a core part and a clad part having different refractive indexes and clad layers respectively formed on both surfaces of the core layer, and an inner conductor layer formed on each of the clad layers An insulating layer formed on each inner conductor layer, a hard substrate bonded to each insulating layer via an adhesive layer, and an outer conductor formed on each hard substrate. A laminated structure having a layer,
The laminated structure is formed by removing a part of each of the hard substrates in the middle of the longitudinal direction , and a flexible part capable of bending deformation, and the remaining parts excluding the flexible part divided into a hard portion made of a part,
The hard portion includes an opening formed by opening the hard substrate, the adhesive layer, and the insulating layer together on one surface side of the core layer, and the core of the outer conductor layers. A conductor post penetrating the hard substrate, the adhesive layer and the insulating layer, electrically connecting the outer conductor layer located on one side of the layer and the inner conductor layer;
In the opening, an element having a plate shape and having a light emitting part or a light receiving part arranged on the core layer side surface and a pair of terminals is installed,
The optical waveguide substrate according to claim 1, wherein at least one of the pair of terminals is electrically connected to the inner conductor layer . The outer conductor layer located on one surface side of the core layer among the outer conductor layers has two wires insulated from each other, and one of the two wires serves as the conductor post. Electrically connected to the inner conductor layer via
One terminal of the pair of terminals is disposed on a surface of the element on the core layer side, and the other terminal is disposed on a surface opposite to the one terminal,
In the element, the one terminal is electrically connected to the inner conductor layer by wire bonding with a metal wire, and the other terminal is connected to the other of the two wirings by soldering. By being electrically connected and energizing between the one wiring and the other wiring, the one terminal and the other terminal are energized, and the light emitting unit or the light receiving unit operates. The optical waveguide forming substrate according to claim 1. The optical waveguide forming substrate according to claim 1 , wherein the core portion of the optical waveguide has a pattern shape that overlaps the light emitting portion or the light receiving portion in a plan view. The optical waveguide forming substrate according to claim 3 , wherein the optical waveguide has a reflecting surface that is inclined with respect to the optical path of the optical waveguide at a portion corresponding to the light emitting unit or the light receiving unit. The optical waveguide forming substrate according to claim 4, wherein the reflecting surface is formed across the core layer and a clad layer located on one surface side of the core layer among the clad layers. The optical waveguide forming substrate is used by being installed in an electronic device having a main body part and a movable part movable with respect to the main body part,
6. The hard part is provided with at least two, one hard part of the two hard parts is installed on the main body part, and the other hard part is installed on the movable part. An optical waveguide forming substrate according to any one of the above. Each said insulating layer is an optical waveguide formation board in any one of Claim 1 thru | or 6 which has a function which bears the intensity | strength of the said flexible part, respectively. The optical waveguide forming substrate according to claim 1, wherein each of the insulating layers has a function of protecting the optical waveguide. 9. The optical waveguide forming substrate according to claim 1, wherein the core portion is made of a material having a higher refractive index than the clad portion and the clad layers. The optical waveguide forming substrate according to claim 9, wherein the constituent materials of the clad part and the clad layers have the same or similar refractive indexes. The core part is formed by selectively irradiating the active energy beam or electron beam to a core layer made of a material whose refractive index changes by irradiation with an active energy beam or electron beam or by further heating. The optical waveguide forming substrate according to claim 1 , wherein the optical waveguide forming substrate is formed in a desired shape. The optical waveguide forming substrate according to claim 11 , wherein the core layer is made of a resin composition containing a cyclic olefin resin. The optical waveguide forming substrate according to claim 12 , wherein the cyclic olefin-based resin is mainly a norbornene-based resin.

Images