JP5126380B2 - Manufacturing method of optical waveguide - Google Patents

Description

The present invention relates to an optical waveguide manufacturing method .

  In recent years, optical branching couplers (optical couplers), optical multiplexers / demultiplexers, and the like have been developed as optical components in the field of optical communications, and optical waveguide devices used for these are promising. As this optical waveguide type element (hereinafter also simply referred to as “optical waveguide”), there are polymer optical waveguides that are easy to manufacture (patterning) and are versatile, in addition to conventional quartz optical waveguides. Has been actively conducted.

  Such an optical waveguide is usually formed in a predetermined arrangement (pattern) on a substrate and handled as an optical waveguide structure. As this optical waveguide structure, a structure in which a predetermined wiring circuit and an optical waveguide composed of a core portion and a cladding portion are formed on a substrate, and a light emitting element and a light receiving element are attached to the optical waveguide is disclosed. (For example, refer to Patent Document 1).

  However, the optical waveguide structure described in Patent Document 1 has the following problems.

1. The process of forming the optical waveguide is complicated, and the degree of freedom in designing and selecting the pattern shape of the core part constituting the optical path of the transmitted light is narrow.
2. The core pattern shape accuracy and dimensional accuracy are poor.
3. When combined with a wiring pattern, the degree of freedom in designing the wiring pattern is narrow.

JP 2004-146602 A

An object of the present invention is to provide an optical waveguide capable of forming a core portion (optical path) having a wide degree of freedom in pattern shape design and high dimensional accuracy by a simple method, and capable of producing an optical waveguide having excellent durability. It is in providing the manufacturing method of.

Such an object is achieved by the present invention of the following (1) to ( 10 ).
(1) A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core portion and a cladding portion having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having an index of refraction different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for manufacturing an optical waveguide, wherein the first clad layer forming layer and the second clad layer forming layer each contain the monomer at a lower ratio than the core layer forming layer .
(2) A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core part and a cladding part having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having a refractive index different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for manufacturing an optical waveguide, wherein the first cladding layer forming layer and the second cladding layer forming layer each contain the substance .
(3) A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core portion and a cladding portion having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having a refractive index different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for producing an optical waveguide, wherein the first cladding layer forming layer and the second cladding layer forming layer each contain the polymer not having the leaving group .

(4) The method for producing an optical waveguide according to any one of (1) to (3), wherein the polymer is mainly a cyclic olefin polymer.

(5) The method for producing an optical waveguide according to any one of (1) to (4), wherein the monomer is compatible with the polymer and can cause a polymerization reaction or a crosslinking reaction in the polymer. .

(6) The method for manufacturing an optical waveguide according to any one of (1) to (5) , wherein the core layer forming layer is irradiated with the actinic radiation, and then the core layer forming layer is subjected to heat treatment. .

(7) The method for producing an optical waveguide according to any one of (1) to (6) , wherein the leaving group is detached by the action of a cation, an anion, or a free radical.

(8) The method for manufacturing an optical waveguide according to any one of (1) to (7) , wherein the substance includes an acid generator.

(9) The method for producing an optical waveguide according to (8) , wherein the leaving group has at least one of an —O— structure, an —Si—aryl structure, and an —O—Si— structure.

(10) The optical waveguide is formed with an optical path conversion part that bends the optical path of the core part,
The optical path changing part is composed of one inclined surface in a recess formed across at least two layers of the core layer and the second cladding layer,
The optical waveguide according to any one of (1) to (9) , wherein after forming the core layer, the recess is formed by removing a part of at least two layers of the core layer and the second cladding layer. Manufacturing method.

  According to the present invention, the core portion can be patterned by a simple method of irradiation with active radiation (active energy ray, electron beam, X-ray, etc.), and the degree of freedom in designing the pattern shape of the core portion is wide. In addition, a core portion with high dimensional accuracy can be obtained.

  In addition, when the core layer is made of a desired material, when the stress is applied to the optical waveguide or deformation occurs, particularly even when repeatedly curved and deformed, delamination between the core portion and the cladding portion, Defects such as the occurrence of microcracks in the core are unlikely to occur, and as a result, the optical transmission performance of the optical waveguide is maintained and the durability is excellent.

  Furthermore, when the core part is composed of a resin composition mainly composed of a norbornene resin (cyclic olefin resin), the core part and the cladding part are highly effective in that they are particularly strong against the deformation and hardly cause defects. The difference in refractive index of the optical waveguide can be further increased, and the optical waveguide is excellent in heat resistance. As a result, an optical waveguide having higher performance and durability is obtained.

According to the present invention as described above, the design range of optical circuits (optical waveguide patterns) and electrical circuits is wide, yield is high, optical transmission performance is maintained high, reliability and durability are excellent, and versatility is achieved. A rich optical waveguide can be easily manufactured . Therefore, the obtained optical waveguide can be used for various electronic components, electronic devices, and the like.

It is sectional drawing which shows 1st Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 2nd Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 3rd Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 4th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 5th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 6th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 7th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 8th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 9th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows 10th Embodiment of the optical waveguide structure which has an optical waveguide manufactured by this invention. It is sectional drawing which shows 11th Embodiment of the optical waveguide structure which has the optical waveguide manufactured by this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 1st manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 4th manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 4th manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 4th manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 4th manufacturing method of the manufacturing method of the optical waveguide of this invention. It is sectional drawing which shows typically the process example of the 4th manufacturing method of the manufacturing method of the optical waveguide of this invention.

Hereinafter, the manufacturing method of the optical waveguide of the present invention is explained in detail based on the suitable embodiment shown in an accompanying drawing.

1 to 11 are sectional views showing embodiments of an optical waveguide structure having an optical waveguide manufactured according to the present invention. Hereinafter, a configuration example of the optical waveguide structure will be described with reference to these drawings. In the following description, the upper side in FIGS. 1 to 11 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).

<First Embodiment: FIG. 1>
As shown in FIG. 1, an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention includes an optical waveguide 9, conductor layers 51 and 52 bonded to both surfaces of the optical waveguide 9, and an optical waveguide 9. The optical path conversion part 96 which bends an optical path, the light emitting element 10, and the electric element 12 are provided.

  The optical waveguide 9 is formed by laminating a clad layer 91, a core layer 93, and a clad layer 92 in this order from the lower side in FIG. 1. 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 a portion that forms an optical path of the transmission light, and the cladding portion 95 does not form an optical path of the transmission light although it is formed in the core layer 93 and performs the same function as the cladding layers 91 and 92. Part.

  In the configuration shown in FIG. 1, a core portion 94 is formed on the left side in FIG. 1 of a later-described reflective surface 961 of the core layer 93, and a cladding portion 95 is formed on the other portion of the core layer 93. .

  As a constituent material of the core layer 93, a material whose refractive index is changed by irradiation with active radiation (active energy ray, electron beam, X-ray or the like) or further heating is used. Preferable examples of such materials include those mainly composed of a resin composition containing a cyclic olefin-based resin such as a benzocyclobutene-based tree polymer or a norbornene-based polymer (resin), including a norbornene-based polymer ( The main material) is particularly preferred.

  The core layer 93 made of such a material is excellent in resistance to deformation such as bending, and even when it is repeatedly curved and deformed, the core layer 94 and the clad portion 95 are separated from each other, and the layer adjacent to the core layer 93 ( The delamination with the clad layers 91 and 92) hardly occurs, and the occurrence of microcracks in the core portion 94 and the clad portion 95 is also prevented. As a result, the optical transmission performance of the optical waveguide 9 is maintained, and the optical waveguide 9 having excellent durability is obtained.

  Examples of the constituent material of the core layer 93 include an antioxidant, a refractive index adjuster, a plasticizer, a thickener, a reinforcing agent, a sensitizer, a leveling agent, an antifoaming agent, an adhesion aid, and a flame retardant. The additive may be contained. Addition of an antioxidant has the effect of improving high temperature stability, improving weather resistance, and suppressing light deterioration. Examples of such an antioxidant include phenols such as monophenols, bisphenols, and triphenols, and aromatic amines. Further, the resistance to bending can be further increased by adding a plasticizer, a thickener, and a reinforcing agent.

  The content of additives typified by the antioxidant (the total in the case of two or more) is preferably about 0.5 to 40% by weight, and 3 to 30% by weight with respect to the entire constituent material of the core layer 93. The degree is more preferable. If this amount is too small, the function of the additive cannot be sufficiently exhibited. If the amount is too large, the transmittance of light (transmitted light) transmitted through the core portion 94 depends on the type and characteristics of the additive. Decrease, patterning failure, refractive index instability and the like.

  An example of a method for forming the core layer 93 is a coating method. Examples of the coating method include a method in which a core layer forming composition (varnish or the like) is applied and cured (solidified), and a method in which a curable monomer composition is applied and cured (solidified). In addition, a method other than the coating method, for example, a method of joining separately manufactured sheet materials may be employed.

  The core layer 93 obtained as described above is selectively irradiated with actinic radiation using a mask to pattern the core portion 94 having a desired shape.

  Examples of the active radiation used for exposure include active energy rays such as visible light, ultraviolet light, infrared light, and laser light, electron beams, and X-rays. The electron beam can be irradiated with an irradiation amount of, for example, about 50 to 2000 KGy.

  In the core layer 93, the refractive index of the portion irradiated with the active radiation changes (the refractive index may increase or decrease depending on the material of the core layer 93), and the active radiation is not irradiated. A difference in refractive index occurs between the parts. For example, the portion of the core layer 93 that has been irradiated with active radiation becomes the cladding portion 954, and the portion that has not been irradiated becomes the core portion 94. The reverse is also true. The refractive index of the cladding part 95 is substantially equal to the refractive index of the cladding layers 91 and 92.

  Moreover, the core part 94 may be formed by irradiating the core layer 93 with actinic radiation in a predetermined pattern and then heating. By adding this heating step, the difference in refractive index between the core portion 94 and the cladding portion 95 becomes larger, which is preferable. This principle will be described later in detail.

  The pattern shape of the core portion 94 to be formed is not particularly limited, and is a straight shape, a shape having a curved portion, an irregular shape, a shape having a branching portion of a light path, a merging portion or a crossing portion, a condensing portion (width, etc. is reduced) Or a light diffusing part (a part where the width or the like is increased), or a combination of two or more of these. The feature of the present invention is that the core portion 94 having any shape can be easily formed by setting the irradiation pattern of the active radiation.

  The constituent material of each part of the optical waveguide 9 and the method of forming the core part 94 will be described in detail later.

  The conductor layer 51 joined to the lower surface of the optical waveguide 9 and the conductor layer 52 joined to the upper surface are each patterned into a predetermined shape to constitute a desired wiring or circuit. Examples of the constituent material of the conductor layers 51 and 52 include various metal materials such as copper, a copper-based alloy, aluminum, and an aluminum-based alloy. Although the thickness of the conductor layers 51 and 52 is not specifically limited, Usually, about 3-120 micrometers is preferable and about 5-70 micrometers is more preferable.

  The conductor layers 51 and 52 are formed by methods such as bonding (adhesion) of metal foil, metal plating, vapor deposition, sputtering, and the like. For example, etching, printing, masking, or the like can be used for patterning the conductor layers 51 and 52.

  The light emitting element 10 includes a light emitting unit 101 and a pair of terminals 103 and 105 on the lower surface side in FIG. The light emitting unit 101 is located between the terminal 103 and the terminal 105. When the terminals 103 and 105 are energized, the light emitting unit 101 emits light.

  In addition, the light emitting part in the light emitting element 10 may be configured by one light emitting point, or may be a group of 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 a light receiving portion 111 in the light receiving element 11 described later.

  The light emitting element 10 is mounted on the optical waveguide 9 such that the terminals 103 and 105 are respectively joined (electrically connected) to predetermined portions of the conductor layer 52.

  The electric element (electronic circuit element) 12 is composed of, for example, a semiconductor element (semiconductor chip). Although the function of the electric element 12 is not particularly limited, an example is one that constitutes a circuit for driving the light emitting element 10. The electric element 12 has two terminals 123 and 125 on the lower surface side in FIG.

  The electric element 12 is mounted on the optical waveguide 9 such that the terminals 123 and 125 are respectively joined (electrically connected) to predetermined portions of the conductor layer 52.

  The lower part including the terminals 103, 105, 123, and 125 of the light emitting element 10 and the electric element 12 is sealed with the underfill material 4. As a result, the gap between the light emitting element 10 and the electric element 12 and the optical waveguide 9 is sealed with the underfill material 4 without forming a gap. Further, the entire light emitting element 10 and electric element 12 (outer surface) are covered and sealed with the sealing material 6. As described above, the light emitting element 10 and the electric element 12 are entirely sealed, and in particular, the light emitting portion 101 is sealed without being exposed to the outside, so that it is protected from dirt, damage, oxidative degradation, and the like. Contributes to improving the reliability of electronic components.

  The underfill material 4 is made of a material that substantially transmits light (transmitted light) emitted from the light emitting unit 101, and is preferably made of a transparent material.

  As a constituent material of the underfill material 4, an insulating resin material is preferable, and examples thereof include an epoxy resin, a phenol resin, a urethane resin, and a polyimide resin.

  Moreover, as a constituent material of the sealing material 6, an insulating resin material is preferable, and examples thereof include an epoxy resin, a phenol resin, a norbornene resin, and a silicon resin.

  As shown in FIG. 1, the optical waveguide 9 is formed with four through holes (through holes) 8 penetrating in the thickness direction. Each through-hole 8 is filled with a conductive material (for example, various metal materials such as copper, copper-based alloy, aluminum, aluminum-based alloy) to form a conductor post 81. The predetermined portions of the conductor layer 51 and the conductor layer 52 are electrically connected to each other through the conductor posts 81. In other words, the terminals 103, 105, 123, and 125 of the light emitting element 10 and the electric element 12 can be energized through the conductor layer 51 on the lower surface side of the optical waveguide 9. Note that the terminal 105 and the terminal 123 are electrically connected and are connected to the ground side.

  The core portion 94 of the optical waveguide 9 has a pattern shape that overlaps with the light emitting portion 101 of the light emitting element 10 in plan view (when viewed from above in FIG. 1) (that is, passes through directly under the light emitting portion 101). Is formed. The core portion 94 has a higher refractive index than that of the cladding portion 95 and has a higher refractive index than the cladding layers 91 and 92. The clad layers 91 and 92 constitute the clad portions located at the lower part and the upper part of the core part 94, respectively. With such a configuration, the core portion 94 functions as a light guide path surrounded by the clad portion on the entire outer periphery.

  Such an optical waveguide 9 has an optical path conversion section 96 that bends the optical path of the core section 94. The optical path conversion unit 96 includes a reflection surface (mirror) 961 that reflects at least a part of the transmission light. The reflecting surface 961 is provided at a position directly below the light emitting unit 101.

  The reflecting surface 961 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, and has a function of reflecting most of the transmitted light (for example, 90% or more).

  Such an optical path conversion unit 96 is formed by removing (deleting) a part of the optical waveguide 9 to form, for example, a triangular concave portion whose bottom is the bottom, and using one inclined surface as the reflective surface 961 It is. The reflection surface 961 may have a reflection film such as a multilayer optical thin film or a metal thin film (for example, an aluminum vapor deposition film) or a reflection increasing film. Although not shown, the concave portion of the optical path conversion unit 96 may be filled with a filler, particularly a filler having a refractive index different from that of the core 94.

  In the configuration shown in the figure, the reflection surface 961 (the optical path conversion unit 96) is formed across the core layer 93 and the clad layer 92, but may be formed only in the core layer 93.

  In the optical waveguide structure 1 of the present embodiment, when power is applied between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the middle and lower is sequentially transmitted through the underfill material 4 and the clad layer 92, reflected by the reflecting surface 961, bent by 90 °, enters the core portion 94 of the optical waveguide 9, and enters the clad portion (cladding). While repeating reflection at the interfaces with the layers 91 and 92 and the side cladding portions 95), the core portion 94 proceeds in the longitudinal direction (left direction in FIG. 1).

  Further, when energization is performed between the terminals 123 and 125 of the electric element 12 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the electric element 12 is driven.

  In FIG. 1, the leftmost conductor post 81 and the core portion 94 are shown to intersect with each other, but these are shifted in the front-rear direction of the paper surface of FIG. This optical path is designed not to interfere with the conductor post 81.

Second Embodiment: FIG. 2
FIG. 2 shows a second embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st Embodiment, and it demonstrates centering around difference.

  In the optical waveguide structure 1 of the present embodiment, the configuration of the optical path conversion unit 96 is different from that described above, and the other configurations are the same. In other words, the reflection surface (mirror) 961 constituting the optical path conversion unit 96 is located directly below the light emitting unit 101, but the reflection surface 961 is formed in three layers of the cladding layer 91, the core layer 93, and the cladding layer 92. It is formed across. That is, the triangular concave portion of the optical path conversion unit 96 is open to the lower surface of the optical waveguide 9.

  The reflective surface 961 may have a reflective film or a reflection enhancement film such as a multilayer optical thin film or a metal thin film, or the concave portion of the optical path conversion unit 96 may be filled with a filler. Is the same as described above.

<Third Embodiment: FIG. 3>
FIG. 3 shows a third embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st Embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of this embodiment has a substrate 2, and an optical waveguide 9 is bonded to the lower surface of the substrate 2 via an adhesive layer 3. Similarly to the underfill material 4, the substrate 2 is made of a material that substantially transmits light (transmission light) emitted from the light emitting unit 101 (a material having translucency with respect to the transmission light). A transparent substrate made of a substantially transparent material.

  More specifically, the optical characteristics of the substrate 2 are preferably such that the transmittance of transmitted light is 80% or more, more preferably 90% or more, and even more preferably 95% or more. Since the board | substrate 2 has such an optical characteristic, the site | part just under the light emission part 101 in the board | substrate 2 comprises the translucent part 21 which permeate | transmits transmission light.

  Similarly, the adhesive layer 3 is made of a material that substantially transmits the transmission light emitted from the light emitting unit 101, and is preferably made of a transparent material.

Examples of the constituent material of the substrate 2 include epoxy resin, phenol resin, bismaleimide resin, bismaleimide / triazine resin, triazole resin, polycyanurate resin, polyisocyanurate resin, benzocyclobutene resin, polyimide resin, polybenzoxazole. Examples thereof include resins and norbornene resins. These materials may be used alone or in combination.
Further, the substrate 2 may be, for example, a fiber base material (woven fabric, non-woven fabric, woven fabric, knitted fabric, etc.) such as glass fiber or resin fiber impregnated with the above-described resin material (prepreg, etc.). For example, a glass cloth impregnated with an epoxy resin is called a glass epoxy substrate, but such a substrate can be used as the substrate 2. The substrate 2 including such a fiber base material is particularly advantageous when the optical waveguide 9 or the conductor layer (metal layer) is bonded to the substrate 2 because the substrate 2 including the fiber base is relatively thin but has high strength and low thermal expansion coefficient. It is.
Moreover, the board | substrate 2 may be a laminated body of a some layer. For example, a laminate of a first layer and a second layer made of resin materials having different compositions (kinds), a layer (sheet material) in which the fiber base material is impregnated with a resin material, and a resin material The thing which laminated | stacked the layer is mentioned. In addition, it cannot be overemphasized that the layer structure in a laminated body is not limited to this.

  Although the thickness of the board | substrate 2 is not specifically limited, Usually, about 50 micrometers-1.2 mm are preferable, and about 100-600 micrometers is more preferable.

  The substrate 2 may be hard (rigid) or flexible (flexible). Moreover, you may have both a hard board | substrate and a flexible board | substrate. In this case, the optical waveguide 9 has only to be formed on at least one of a hard substrate and a flexible substrate, and may be formed over both.

  As the adhesive layer 3, 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.

  The adhesive layer 3 may be formed by a coating film on the lower surface of the substrate 2 or the upper surface of the optical waveguide 9 without using a sheet material as the adhesive layer 3. The adhesive layer 3 may be a laminate of two or more layers.

  Although the thickness of the contact bonding layer 3 is not specifically limited, About 0.5-150 micrometers is preferable and about 10-70 micrometers is more preferable.

  The conductor layer 52 is formed on the upper surface of the substrate 2. In this case, a part of the conductor layer 52 is exposed outward from the sealing material 6. The conductor layer 51 formed on the lower surface of the optical waveguide 9 has a wiring pattern different from that of the first embodiment.

  As shown in FIG. 3, two conductor posts 81 are provided so as to penetrate the optical waveguide 9, the adhesive layer 3, and the substrate 2, and the conductor layer 51 and the conductor layer 52 are predetermined via these conductor posts 81. The parts are conducting. That is, the terminal 105 of the light emitting element 10 and the terminal 123 of the electric element 12 are conducted through the conductor layer 51, the conductor post 81, and the conductor layer 52, and these are connected to the ground side.

  When a current is applied between one conductor layer 52 and the conductor layer 51 exposed to the outside from the sealing material 6, the light emitting portion 101 emits light, and the other conductor layer 52 and the conductor exposed to the outside from the sealing material 6. When energized with the layer 51, the electric element 12 is driven.

  In the optical waveguide structure 1 of the present embodiment, when power is applied between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the middle and lower is sequentially transmitted through the underfill material 4, the substrate 2 (translucent portion of the substrate 2), the adhesive layer 3, and the cladding layer 92, reflected by the reflecting surface 961, and bent by 90 °. The core portion 94 of the optical waveguide 9 enters the core portion 94 while being repeatedly reflected at the interface with the clad portions (cladding layers 91 and 92 and the side clad portions 95). )

<Fourth Embodiment: FIG. 4>
FIG. 4 shows a fourth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st and 3rd embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of this embodiment does not have the adhesive layer 3, except that the substrate 2 and the optical waveguide 9 are directly joined and the configuration of the optical path conversion unit 96 is different. This is the same as the embodiment. Since the board | substrate 2 and the optical waveguide 9 are directly joined, it contributes to thickness reduction of the optical waveguide structure 1. FIG.

  The reflection surface (mirror) 961 constituting the optical path conversion unit 96 is located directly below the light emitting unit 101. The reflection surface 961 extends over three layers of the clad layer 91, the core layer 93, and the clad layer 92. Is formed. In other words, the optical path conversion unit 96 is configured by a triangular recess having a base on the upper side, and a reflecting surface 961 is formed on the slope. Such an optical path conversion unit 96 is provided adjacent to the substrate 2.

  The reflective surface 961 may have a reflective film or a reflection enhancement film such as a multilayer optical thin film or a metal thin film, or the concave portion of the optical path conversion unit 96 may be filled with a filler. Is the same as described above.

  In the optical waveguide structure 1 of the present embodiment, when the current is passed between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the middle and lower is sequentially transmitted through the underfill material 4 and the substrate 2, reflected by the reflecting surface 961, bent by 90 °, enters the core portion 94 of the optical waveguide 9, and enters the cladding portion (cladding layer). 91, 92, and the clad part 95) on the side, and repeats reflection at the interface with the core part 94 along the longitudinal direction (left direction in FIG. 4).

<Fifth Embodiment: FIG. 5>
FIG. 5 shows a fifth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st and 3rd embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of the present embodiment is the same as the third embodiment except for the configuration of the substrate 2. That is, the substrate 2 does not have a sufficient transmission light transmission property, and a through hole 22 penetrating the substrate 2 is formed at a position directly below the light emitting unit 101 in the substrate 2. The through hole 22 constitutes a light transmitting part 21 that transmits the transmitted light. That is, the through hole 22 serves as a light guide for guiding (transmitting) transmission light in the thickness direction of the substrate 2.

  Although not shown in the drawing, the inside (all or a part) of the through-hole 22 is filled with a filler made of a material having a transmission light transmittance of 80% or more, preferably 90% or more, more preferably 95% or more. May be. Although not shown, by forming a layer made of a conductive material on the inner surface of the through hole 22 or the like, in addition to the optical transmission function, a function of transmitting an electrical signal may be provided.

  In the optical waveguide structure 1 of the present embodiment, when power is applied between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the lower middle passes through the underfill material 4, passes through the through hole 22, passes through the adhesive layer 3 and the cladding layer 92, is reflected by the reflecting surface 961, and bends by 90 °. While entering the core portion 94 of the waveguide 9 and repeating reflection at the interface with the cladding portions (cladding layers 91 and 92 and the side cladding portions 95), the inside of the core portion 94 is in the longitudinal direction (left direction in FIG. 5). Proceed along.

<Sixth Embodiment: FIG. 6>
FIG. 6 shows a sixth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st, 4th and 5th embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of this embodiment is obtained by replacing the substrate 2 in the optical waveguide structure 1 of the fourth embodiment with the substrate 2 of the fifth embodiment. That is, the substrate 2 in the optical waveguide structure 1 of the present embodiment does not have a sufficient transmission light transmission property, and a through-hole (substrate 2) that penetrates the substrate 2 at a position directly below the light emitting unit 101. ) 22 in the thickness direction. The through hole 22 constitutes the light transmitting part 21.

  In the optical waveguide structure 1 of the present embodiment, when power is supplied between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. Light emitted toward the middle and lower passes through the underfill material 4, passes through the through-hole 22, is reflected by the reflecting surface 961, bends 90 °, enters the core portion 94 of the optical waveguide 9, and enters the cladding portion. The light travels along the longitudinal direction (left direction in FIG. 6) in the core portion 94 while repeating reflection at the interfaces with the cladding layers 91 and 92 and the side cladding portions 95.

<Seventh Embodiment: FIG. 7>
FIG. 7 shows a seventh embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st and 5th embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of the present embodiment is different from the fifth embodiment in the configuration of the light transmitting part (light guide path formed in the thickness direction) 21 of the substrate 2, and the other parts are the same as in the fifth embodiment. . That is, a vertical optical waveguide 23 composed of a core portion 24 and a clad portion 25 surrounding the outer periphery of the core portion 24 is inserted into a through hole 22 formed at a position directly below the light emitting portion 101 of the substrate 2. Has been.

  The constituent material and the forming method of the core part 24 can be the same as those of the core part 94. Alternatively, the core part 24 may be the same as the filler in the through hole 22 described in the fifth embodiment. The constituent material of the clad part 25 can be the same as that of the clad part 95 or the clad layers 91 and 92.

  In the optical waveguide structure 1 of the present embodiment, when the current is passed between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the middle and lower passes through the underfill material 4, passes through the core portion 24 of the vertical optical waveguide 23, passes through the adhesive layer 3 and the cladding layer 92, and is reflected by the reflecting surface 961 to be 90. ° Bends, enters the core portion 94 of the optical waveguide 9, and repeats reflection at the interface with the clad portions (cladding layers 91 and 92 and the side clad portions 95), while passing through the core portion 94 in the longitudinal direction (FIG. 7). (Middle left)

<Eighth embodiment: FIG. 8>
FIG. 8 shows an eighth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st and 6th embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of the present embodiment is the same as that of the seventh embodiment in the configuration of the light guide formed in the thickness direction of the substrate 2 in the optical waveguide structure 1 of the sixth embodiment. is there. That is, a vertical optical waveguide 23 composed of a core portion 24 and a clad portion 25 surrounding the outer periphery of the core portion 24 is inserted into a through hole 22 formed at a position directly below the light emitting portion 101 of the substrate 2. Has been.

  In the optical waveguide structure 1 of the present embodiment, when the current is passed between the terminals 103 and 105 of the light emitting element 10 through the conductor layer 51, the conductor post 81, and the conductor layer 52, the light emitting unit 101 is turned on, and FIG. The light emitted toward the middle and lower passes through the underfill material 4, passes through the core portion 24 of the vertical optical waveguide 23, is reflected by the reflecting surface 961, and is bent by 90 °, and the core portion 94 of the optical waveguide 9. Then, while reflecting repeatedly at the interface with the cladding part (cladding layers 91 and 92 and the side cladding part 95), the core part 94 advances in the longitudinal direction (left direction in FIG. 8).

<Ninth Embodiment: FIG. 9>
FIG. 9 shows a ninth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st and 8th embodiment, and it demonstrates centering around difference.

  The optical waveguide structure 1 of the present embodiment is the same as that of the eighth embodiment except that the light transmitting portion 21 is provided with a lens portion 26 that can condense or diffuse transmission light. That is, a lens portion 26 composed of a convex lens (more precisely, a plano-convex lens) is provided on the upper end surface (incident side) of the vertical optical waveguide 23.

  As a result, the light emitted downward from the light emitting unit 101 in FIG. 9 is transmitted through the underfill material 4 and then condensed by the lens unit 26 to narrow the light beam (beam). It passes through the core portion 24 of the optical waveguide 23, is reflected by the reflecting surface 961, is bent by 90 °, enters the core portion 94 of the optical waveguide 9, and passes through the core portion 94 along the longitudinal direction (left direction in FIG. 9). Go ahead. By providing such a lens portion 26, clearer (sharp) transmitted light can be obtained, and more excellent light transmission characteristics can be obtained.

  The lens unit 26 may be capable of diffusing transmitted light. In this case, a concave lens may be used.

  In addition, the installation position of the lens unit 26 is not limited to the position illustrated in FIG. It may be an emission side end.

<Tenth Embodiment: FIG. 10>
FIG. 10 shows a tenth embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st, 2nd embodiment, etc., and it demonstrates centering around difference.

  Conductive layers 51 and 52 having a predetermined pattern shape are bonded to the lower surface and the upper surface of the optical waveguide 9 constituted by the clad layers 91 and 92 and the core layer 93 located (interposed) therebetween. The predetermined portions of the conductor layer 51 and the conductor layer 52 are electrically connected to each other by two conductor posts 81 formed through the optical waveguide 9.

  In addition, two optical path conversion parts 96a and 96b are formed in the optical waveguide 9. These optical path conversion units 96a and 96b have reflection surfaces 961a and 961b similar to those described above. In the optical waveguide 9, a core portion 94 is formed on the left side in FIG. 10 from the reflecting surface 961 a of the core layer 93 and the right side in FIG. 10 from the reflecting surface 961 b, and the other portion of the core layer 93 is the cladding portion 95. Is formed.

  A chip carrier (element) 13 is mounted on the optical waveguide 9. The chip carrier 13 includes a substrate 2 ′, an optical waveguide 9 ′ different from the optical waveguide 9, a light emitting element 10, a light receiving element 11, conductor layers 54 and 55, and an electric element 12. Hereinafter, the configuration of the chip carrier 13 will be described in detail.

  An optical waveguide 9 ′ composed of clad layers 91, 92 and a core layer 93 positioned (interposed) therebetween is joined to the lower surface of the substrate 2 ′. In addition, conductor layers 54 and 55 having a predetermined pattern shape are bonded to the upper surface of the substrate 2 ', respectively. Constituent materials, formation methods, patterning methods, and the like of the conductor layers 54 and 55 are the same as those of the conductor layers 51 and 52.

  The substrate 2 'may be substantially transparent or opaque, and may be rigid (rigid) or flexible (flexible).

  Predetermined portions of the conductor layer 54 and the conductor layer 55 are electrically connected to each other by four conductor posts 82 formed through the substrate 2 ′ and the optical waveguide 9 ′.

  Further, four optical path conversion parts 96c, 96d, 96e, 96f are formed in the optical waveguide 9 '. These optical path conversion units 96c, 96d, 96e, and 96f have reflection surfaces 961c, 961d, 961e, and 961f similar to those described above.

  In the optical waveguide 9 ′, a core portion 94 is formed at a portion between the reflecting surface 961 c and the reflecting surface 961 d of the core layer 93 and a portion between the reflecting surface 961 e and the reflecting surface 961 f. The clad part 95 is formed in the other part.

  An electric element (semiconductor element) 12 including four terminals 123, 125, 127, and 129 is mounted on the substrate 2 '. The electric element 12 is mounted on the substrate 2 ′ so that the terminals 123, 125, 127, and 129 are joined (electrically connected) to predetermined portions of the conductor layer 55.

  Although the function of the electric element 12 is not particularly limited, an example is one that constitutes a circuit for driving the light emitting element 10. The electric element 12 may further have a function (circuit) for processing (for example, signal amplification) the electric signal output from the light receiving element 11.

  Such an electric element 12 is entirely covered (sealed) with a sealing material 61 similar to the sealing material 6 and sealed.

  A light emitting element 10 and a light receiving element 11 are mounted below the optical waveguide 9 '. The light emitting element 10 is the same as described above. The light receiving element 11 has a light receiving portion 111 and a pair of terminals 113 and 115 on the upper surface side in FIG. The light receiving unit 111 is located between the terminal 113 and the terminal 115. When the light receiving unit 111 receives light (irradiates transmission light), the light is photoelectrically converted, a potential difference is generated between the terminals 113 and 115, and an electric signal is output.

  The light emitting element 10 is mounted below the optical waveguide 9 ′ such that the terminals 103 and 105 are joined (electrically connected) to predetermined portions of the conductor layer 54. The light receiving element 11 is mounted below the optical waveguide 9 ′ so that the terminals 113 and 115 are respectively joined (electrically connected) to predetermined portions of the conductor layer 54.

  The light emitting element 10 and the light receiving element 11 have their upper portions including the terminals 103, 105, 113, 115 sealed with the underfill material 4, and the light emitting element 10 and the light receiving element 11 as a whole (outer surface) It is covered and sealed with a sealing material 6.

  The core portion 94 of the optical waveguide 9 ′ overlaps the light emitting portion 101 of the light emitting element 10 and the light receiving portion 111 of the light receiving element 11 in plan view (when viewed from above in FIG. 10) (that is, the light emitting portion 101). And a pattern shape (passing right above the light receiving portion 111).

  The reflective surface 961d is provided at a position directly above the light emitting unit 101, the reflective surface 961e is provided at a position directly above the light receiving unit 111, and the reflective surface 961c is at a position directly above the reflective surface 961a. The reflection surface 961f is provided at a position directly above the reflection surface 961b.

  Such a chip carrier 13 is mounted on the optical waveguide 9 such that predetermined portions of the conductor layer 52 and the conductor layer 54 are electrically connected by solder (solder balls) 7. In this case, the space between the optical waveguides 9 and 9 ′ is sealed with an underfill material 41 similar to the underfill material 4.

  A part of the conductor layer 52 is sealed with the underfill material 41, and a part of the conductor layer 52 is exposed to the outside without being sealed with the underfill material 41.

  In the optical waveguide structure 1 of the present embodiment, when power is supplied between the terminals 103 and 105 of the light emitting element 10, the light emitting unit 101 is turned on, and the light emitted upward in FIG. 4, reflected by the reflecting surface 961 d and bent by 90 °, enters the core portion 94 of the optical waveguide 9 ′, and advances in the core portion 94 along the longitudinal direction (left direction in FIG. 10). Further, the transmission light emitted from the end portion of the core portion 94 is reflected by the reflecting surface 961c, bent 90 °, travels downward, passes through the underfill material 41 and the cladding layer 92, and is reflected by the reflecting surface 961a. It bends by 90 °, enters the core portion 94 of the optical waveguide 9, and advances in the core portion 94 along its longitudinal direction (left direction in FIG. 10).

  On the other hand, the light that enters the core portion 94 from the right side of the optical waveguide 9 in FIG. 10 travels along the longitudinal direction (left direction in FIG. 10) in the core portion 94, is reflected by the reflecting surface 961b, and bends 90 °. Then, it passes upward, passes through the cladding layer 92 and the underfill material 41, is reflected by the reflecting surface 961f, bends 90 °, enters the core portion 94 of the optical waveguide 9 ′, and enters the core portion 94 in its longitudinal direction ( Proceed along the left direction in FIG. Further, the transmission light emitted from the end portion of the core portion 94 is reflected by the reflecting surface 961e, bent 90 °, travels downward, passes through the underfill material 4, and is received by the light receiving portion 111. As a result, a potential difference is generated between the terminals 113 and 115, and an electric signal is output.

<Eleventh embodiment: FIG. 11>
FIG. 11 shows an eleventh embodiment of an optical waveguide structure 1 having an optical waveguide manufactured according to the present invention. Hereinafter, although this optical waveguide structure 1 is demonstrated, the description is abbreviate | omitted about the matter similar to the said 1st, 6th, 10th Embodiment, etc., and it demonstrates centering around difference.

  An optical waveguide 9 composed of clad layers 91 and 92 and a core layer 93 positioned (interposed) therebetween is bonded to the lower surface of the substrate 2. The conductor layer 52 having the pattern shape is joined.

  In addition, two optical path conversion parts 96a and 96b are formed in the optical waveguide 9. The optical path conversion units 96a and 96b have the same configuration as the optical path conversion unit 96 in the fourth, eighth, and ninth embodiments, and have the same reflecting surfaces 961a and 961b, respectively.

  In the optical waveguide 9, a core portion 94 is formed on the left side in FIG. 11 from the reflecting surface 961 a of the core layer 93 and the right side in FIG. 11 from the reflecting surface 961 b, and the other portion of the core layer 93 is the cladding portion 95. Is formed.

  The substrate 2 does not have sufficient transmission light transmission (translucency), and the substrate 2 has a position directly above the reflection surfaces 961a and 961b (a position directly below the reflection surfaces 961c and 961f). Each of the through holes 22 is formed through the substrate 2. These through holes 22 constitute a light transmitting portion 21 that transmits the transmitted light. That is, these through holes 22 serve as a light guide for guiding (transmitting) transmission light in the thickness direction of the substrate 2.

  Moreover, the lens part 26 similar to the said 9th Embodiment is provided in the upper part of both the through-holes 22 (translucent part 21), respectively. For example, the through hole 22 is filled with a transparent first resin material having a relatively low refractive index, and the upper surface thereof is formed into a curved concave surface, and the concave surface is transparent with a higher refractive index than the first resin material. By filling the second resin material, it is possible to form the lens portion 26 in which the portion of the second resin material functions as a convex lens (plano-convex lens, biconvex lens, etc.). In addition, the present invention is not limited thereto, and only a convex lens (a plano-convex lens, a biconvex lens, etc.) may be installed in the through hole 22.

  Moreover, the installation position of the lens part 26 with respect to the through-hole 22 (light-transmitting part 21) is not limited to the upper part as illustrated, and may be in the middle or lower part of the through-hole 22.

  Although not shown in the drawing, the inside (all or a part) of the through-hole 22 is filled with a filler made of a material having a transmission light transmittance of 80% or more, preferably 90% or more, more preferably 95% or more. May be. Further, as in the seventh and eighth embodiments, the vertical optical waveguide 23 may be formed inside the through hole 22.

  A chip carrier (element) 13 similar to that of the tenth embodiment is mounted on the top of the optical waveguide 9 with the substrate 2.

  In the optical waveguide structure 1 of the present embodiment, when the current is applied between the terminals 103 and 105 of the light emitting element 10, the light emitting unit 101 is turned on, and the light emitted upward in FIG. 4, reflected by the reflecting surface 961 d and bent by 90 °, enters the core portion 94 of the optical waveguide 9 ′, and advances in the core portion 94 along the longitudinal direction (left direction in FIG. 11). Further, the transmission light emitted from the end portion of the core portion 94 is reflected by the reflecting surface 961c, bent 90 °, travels downward, passes through the underfill material 41, and then is condensed by the lens portion 26 and the light flux. (Beam) is narrowed down, this light beam passes through the through hole 22, is reflected by the reflecting surface 961 a, bends 90 °, enters the core portion 94 of the optical waveguide 9, and enters the core portion 94 in its longitudinal direction (FIG. 11). (Middle left)

  On the other hand, the light that enters the core portion 94 from the right side of the optical waveguide 9 in FIG. 11 travels along the longitudinal direction (left direction in FIG. 11) in the core portion 94, is reflected by the reflecting surface 961b, and bends 90 °. Then, the light passes through the through-hole 22 and is condensed by the lens portion 26 to narrow the light beam (beam). The light beam is transmitted through the underfill material 41, reflected by the reflecting surface 961f, and bent by 90 °. Then, the light enters the core portion 94 of the optical waveguide 9 ′ and proceeds along the longitudinal direction (left direction in FIG. 11) in the core portion 94. Further, the transmission light (condensed light beam) emitted from the end of the core portion 94 is reflected by the reflecting surface 961e, bent 90 °, travels downward, passes through the underfill material 4, and is received by the light receiving portion 111. Received light. As a result, a potential difference is generated between the terminals 113 and 115, and an electric signal is output.

  The first to eleventh embodiments have been described above. However, the present invention is not limited to these, and other configurations may be used as long as the gist of the invention is not changed. Further, the present invention may be a combination of configurations included in any two or more of the first to eleventh embodiments.

  Next, the manufacturing method of the optical waveguides 9 and 9 ′ and the constituent materials of each part in each of the above embodiments will be described. In particular, the method for forming the core part 94 will be described in detail.

<First manufacturing method>
First, the 1st manufacturing method of the optical waveguide 9 is demonstrated. The manufacturing method of the optical waveguide 9 ′ is the same as that of the optical waveguide 9, and is represented by the optical waveguide 9.

  FIGS. 12A to 12E are cross-sectional views schematically showing a process example of the first manufacturing method of the optical waveguide.

[1A] First, a layer 910 is formed over a supporting substrate 951 (see FIG. 12A).
The layer 910 is formed by a method in which a core layer forming material (varnish) 900 is applied and cured (solidified).

  Specifically, the layer 910 is formed by applying the core layer forming material 900 on the support substrate 951 to form a liquid film, and then placing the support substrate 951 on a ventilated level table so that the surface of the liquid film is not coated. It is formed by leveling the uniform part and evaporating (desolving) the solvent.

  When the layer 910 is formed by a coating method, examples thereof include a doctor blade method, 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. It is not done.

  As the support substrate 951, for example, a silicon substrate, a silicon dioxide substrate, a glass substrate, a quartz substrate, a polyethylene terephthalate (PET) film, or the like is used.

  The core layer forming material 900 contains a light-induced heat-developable material (PITDM) composed of a polymer 915 and an additive 920 (in this embodiment, including at least a monomer, a promoter, and a catalyst precursor). It is a material in which a monomer reaction occurs in the polymer 915 by irradiation with actinic radiation and heating.

  In the resulting layer 910, any polymer (matrix) 915 is distributed substantially uniformly and randomly, and the additive 920 is substantially uniformly and randomly dispersed within the polymer 915. ing. Thereby, the additive 920 is substantially uniformly and arbitrarily dispersed in the layer 910.

  The average thickness of the layer 910 is appropriately set according to the thickness of the core layer 93 to be formed, and is not particularly limited, but is preferably about 5 to 200 μm, and preferably about 10 to 100 μm. More preferably, it is about 15 to 65 μm.

  The polymer 915 has sufficiently high transparency (colorless and transparent) and is compatible with the monomer described later, and the monomer can react (polymerization reaction or crosslinking reaction) as described later. Even after the monomers are polymerized, those having sufficient transparency are preferably used.

  Here, “having compatibility” means that the monomer is at least mixed and does not cause phase separation with the polymer 915 in the core layer forming material 900 or the layer 910.

  Examples of such a polymer 915 include cyclic olefin resins such as norbornene resins and benzocyclobutene resins, acrylic resins, methacrylic resins, polycarbonate, polystyrene, epoxy resins, polyamides, polyimides, polybenzoxazoles, and the like. Among them, one or a combination of two or more thereof (polymer alloy, polymer blend (mixture), copolymer, etc.) can be used.

  Among these, those mainly composed of norbornene resins (norbornene polymers) are preferable. By using a norbornene-based polymer as the polymer 915, the core layer 93 having excellent optical transmission performance and heat resistance can be obtained.

  Moreover, since norbornene-type polymer has high hydrophobicity, the core layer 93 which cannot produce the dimensional change by water absorption etc. easily can be obtained.

  The norbornene polymer may be either one having a single repeating unit (homopolymer) or one having two or more norbornene repeating units (copolymer).

  Examples of such norbornene-based polymers include (1) addition (co) polymers of norbornene monomers obtained by addition (co) polymerization of norbornene monomers, and (2) norbornene monomers and ethylene or α-olefins. (3) addition polymers such as addition copolymers with norbornene-type monomers and non-conjugated dienes, and other monomers as required, (4) ring opening of norbornene-type monomers ( A (co) polymer, and a resin obtained by hydrogenating the (co) polymer if necessary, (5) a ring-opening copolymer of a norbornene-type monomer and ethylene or α-olefins, and ( (Co) polymer hydrogenated resin, (6) ring-opening copolymer of norbornene type monomer and non-conjugated diene or other monomer, and (co) polymerization if necessary And a ring-opening polymer such as a polymer obtained by hydrogenating the body. Examples of these polymers include random copolymers, block copolymers, and alternating copolymers.

  These norbornene-based polymers include, for example, ring-opening metathesis polymerization (ROMP), combination of ROMP and hydrogenation reaction, polymerization by radical or cation, polymerization using a cationic palladium polymerization initiator, and other polymerization initiators ( For example, it can be obtained by any known polymerization method such as polymerization using a polymerization initiator of nickel or another transition metal).

  Among these, as the norbornene-based polymer, those having at least one repeating unit represented by the following chemical formula 1 (Structural Formula B), that is, an addition (co) polymer is preferable. This is preferable because it is rich in transparency, heat resistance and flexibility.

  Such a norbornene polymer is suitably synthesized by using, for example, a norbornene monomer described later (a norbornene monomer represented by Chemical Formula 3 described below or a crosslinkable norbornene monomer).

  In order to obtain a polymer 915 having a relatively high refractive index, a monomer having an aromatic ring (aromatic group), a nitrogen atom, a bromine atom or a chlorine atom in the molecular structure is generally selected, A polymer 915 is synthesized (polymerized). On the other hand, in order to obtain a polymer 915 having a relatively low refractive index, a monomer having an alkyl group, a fluorine atom or an ether structure (ether group) is generally selected in the molecular structure, and the polymer 915 is synthesized ( Polymerization).

  As the norbornene-based polymer having a relatively high refractive index, those containing a repeating unit of aralkylnorbornene are preferable. Such norbornene-based polymers have a particularly high refractive index.

  Examples of the aralkyl group (arylalkyl group) of the aralkylnorbornene repeating unit include benzyl group, phenylethyl group, phenylpropyl group, phenylbutyl group, naphthylethyl group, naphthylpropyl group, fluorenylethyl group, fluorene group, and the like. Examples thereof include a nylpropyl group, and a benzyl group and a phenylethyl group are particularly preferable.

  A norbornene-based polymer having such a repeating unit is preferable because it has a very high refractive index.

  Further, the norbornene-based polymer preferably contains an alkylnorbornene repeating unit. Since a norbornene-based polymer containing a repeating unit of alkylnorbornene has high flexibility, high flexibility (flexibility) can be imparted to the optical waveguide 9 by using such norbornene-based polymer.

  Examples of the alkyl group that the alkylnorbornene repeating unit has include a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, and a hexyl group is particularly preferable. These alkyl groups may be either linear or branched.

  By including the repeating unit of hexyl norbornene, it is possible to prevent the refractive index of the entire norbornene-based polymer from being lowered and to maintain high flexibility.

  Here, for example, the optical waveguide 9 is preferably used in data communication using light in a wavelength region of about 600 to 1550 nm. However, the norbornene-based polymer including a repeating unit of hexyl (alkyl) norbornene is as described above. It is preferable because it has excellent transmittance with respect to light in a large wavelength region (particularly, a wavelength region near 850 nm).

  Preferred examples of such norbornene polymers include hexyl norbornene homopolymer, phenylethyl norbornene homopolymer, benzyl norbornene homopolymer, hexyl norbornene and phenylethyl norbornene copolymer, and hexyl norbornene and benzyl norbornene copolymer. However, it is not limited to these.

  The core layer forming material 900 of this embodiment includes a monomer, a promoter (first substance), and a catalyst precursor (second substance) as the additive 920.

  The monomer reacts in the active radiation irradiated region by irradiation with actinic radiation, which will be described later, and forms a reactant. Due to the presence of this reactant, the monomer refracts in the irradiated region in the layer 910 and in the non-active radiation irradiated region. It is a compound that can cause a rate difference.

  Here, as this reaction product, a polymer (polymer) formed by polymerizing a monomer in a polymer (matrix) 915, a crosslinked structure that cross-links the polymers 915, and a polymer 915 that is polymerized from the polymer 915 Examples thereof include at least one of branched structures (branch polymer and side chain (pendant group)).

  Here, in the layer 910, when it is desired that the refractive index of the irradiated region is high, a polymer 915 having a relatively low refractive index and a monomer having a high refractive index with respect to the polymer 915 are combined. When used and it is desired that the refractive index of the irradiated region be low, a polymer 915 having a relatively high refractive index and a monomer having a low refractive index for this polymer 915 are used in combination.

  Note that “high” or “low” in the refractive index does not mean the absolute value of the refractive index but means a relative relationship between certain materials.

  When the refractive index of the irradiated region in the layer 910 decreases due to the monomer reaction (reactant generation), the portion becomes the cladding portion 95, and when the refractive index of the irradiated region increases, the portion becomes the core portion 94. It becomes.

  Such a monomer is not particularly limited as long as it is a compound having a polymerizable site, and examples thereof include norbornene monomers, acrylic acid (methacrylic acid) monomers, epoxy monomers, styrene monomers, and the like. These can be used alone or in combination of two or more.

  Among these, it is preferable to use a norbornene-based monomer as the monomer. By using the norbornene-based monomer, the core layer 93 (optical waveguide 9) having excellent optical transmission performance and excellent heat resistance and flexibility can be obtained.

  Here, the norbornene-based monomer is a generic term for monomers containing at least one norbornene skeleton represented by the following chemical formula 2 (structural formula A), and examples thereof include compounds represented by the following chemical formula 3 (structural formula C). .

［式中、ａは、単結合または二重結合を表し、Ｒ^１〜Ｒ^４は、それぞれ独立して、水素原子、置換もしくは無置換の炭化水素基、または官能置換基を表し、ｍは、０〜５の整数を表す。ただし、ａが二重結合の場合、Ｒ^１およびＲ^２のいずれか一方、Ｒ^３およびＲ^４のいずれか一方は存在しない。］

[Wherein, a represents a single bond or a double bond, R ^{1 to} R ⁴ each independently represents a hydrogen atom, a substituted or unsubstituted hydrocarbon group, or a functional substituent; Represents an integer of 0 to 5; However, when a is a double bond, either one of R ¹ and R ² or one of R ³ and R ⁴ does not exist. ]

Examples of the unsubstituted hydrocarbon group (hydrocarbyl group) include, for example, a linear or branched alkyl group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ), a linear or branched carbon number of 2 -10 (C ₂ -C ₁₀ alkenyl group, linear or branched alkynyl group having 2 to 10 carbon atoms (C ₂ -C ₁₀ ), cycloalkyl having 4 to 12 carbon atoms (C ₄ -C ₁₂ ) Group, C 4-12 (C ₄ -C ₁₂ ) cycloalkenyl group, C 6-12 (C ₆ -C ₁₂ ) aryl group, C 7-24 (C ₇ -C ₂₄ ) aralkyl group In addition, R ¹ and R ² , R ³ and R ⁴ may each be an alkylidenyl group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ).

  Specific examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group. , Nonyl and decyl groups, but are not limited thereto.

  Specific examples of the alkenyl group include, but are not limited to, a vinyl group, an allyl group, a butenyl group, and a cyclohexenyl group.

  Specific examples of the alkynyl group include, but are not limited to, ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group and 2-butynyl group.

  Specific examples of the cycloalkyl group include, but are not limited to, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

  Specific examples of the aryl group include, but are not limited to, a phenyl group, a naphthyl group, and an anthracenyl group.

  Specific examples of the aralkyl group include, but are not limited to, a benzyl group and a phenylethyl (phenethyl) group.

  Further, specific examples of the alkylidenyl group include, but are not limited to, a methylidenyl group and an ethylidenyl group.

  Examples of the substituted hydrocarbon group include those in which some or all of the hydrogen atoms of the hydrocarbon group are substituted with halogen atoms, that is, halohydrocarbyl groups, perhalohydrocarbyl groups. Or halogenated hydrocarbon groups such as perhalocarbyl groups.

  In these halogenated hydrocarbon groups, the halogen atom substituted with a hydrogen atom is preferably at least one selected from a chlorine atom, fluorine and bromine, more preferably a fluorine atom.

  Among these, specific examples of the perhalogenated hydrocarbon group (perhalohydrocarbyl group, perhalocarbyl group) include, for example, a perfluorophenyl group, a perfluoromethyl group (trifluoromethyl group), and a perfluoroethyl group. Perfluoropropyl group, perfluorobutyl group, perfluorohexyl group and the like.

As the halogenated alkyl group, those having 11 to 20 carbon atoms can be suitably used in addition to those having 1 to 10 carbon atoms. That is, as the halogenated alkyl group, a group that is partially or completely halogenated, linear or branched, and represented by the general formula: —C _Z X ″ _{2Z + 1} can be selected. Here, X '' represents a halogen atom or a hydrogen atom each independently, and Z represents the integer of 1-20.

In addition to the halogen atom, the substituted hydrocarbon group may be a linear or branched alkyl group having 1 to 5 carbon atoms (C _{1 to} C ₅ ), a haloalkyl group, an aryl group, and a cycloalkyl group. Examples thereof include a substituted cycloalkyl group, aryl group and aralkyl group (aralkyl group).

Moreover, as a functional substituent, for example, — (CH ₂ ) _n —CH (CF ₂ ) ₂ —O—Si (Me) ₃ , — (CH ₂ ) _n —CH (CF ₃ ) ₂ —O—CH ₂ —O—CH ₃ , — (CH ₂ ) _n —CH (CF ₃ ) ₂ —O—C (O) —O—C (CH ₃ ) ₃ , — (CH ₂ ) _n —C (CF ₃ ) ₂ — OH, — (CH ₂ ) _n —C (O) —NH ₂ , — (CH ₂ ) _n —C (O) —Cl, — (CH ₂ ) _n —C (O) —O—R ⁵ , — ( ^{_{CH 2) n-O-R}} 5, - (CH 2) n -O-C (O) -R 5, - (CH 2) n -C (O) -R 5, - (CH 2) n -O —C (O) —OR ⁵ , — (CH ₂ ) _n —Si (R ⁵ ) ₃ , — (CH ₂ ) _n —Si (OR ⁵ ) ₃ , — (CH ₂ ) _n —O—Si (R ⁵⁾ ) ₃ and-(C _{H 2) n -C (O)} -OR 6 , and the like.

Here, in each of the formulas above, each, n is an integer of 0, ^{R 5} are each independently a hydrogen atom, a linear or branched C 1 to 20 _(C 1 -C ₂₀₎ alkyl group, a linear or branched halogenated or perhalogenated alkyl group having a carbon number 1 to 20 _(C 1 _{-C 20)} linear or branched C 2 to 10 _(C 2 ~ alkenyl group of C _10), a linear or branched alkynyl group having 2 to 10 carbon atoms _(C 2 _{~C 10),} a cycloalkyl group having 5 to 12 carbon atoms _(C 5 _{~C 12),} to 6 carbon atoms -14 (C ₆ -C ₁₄ ) aryl group, C 6-14 (C ₆ -C ₁₄ ) halogenated or perhalogenated aryl group or C 7-24 (C ₇ -C ₂₄ ) aralkyl group Represents.

Incidentally, the hydrocarbon group represented by R ⁵ represents the same hydrocarbon groups as those represented by R ¹ to R ^4. As represented by R ^{1 to} R ⁴ , the hydrocarbon group represented by R ⁵ may be halogenated or perhalogenated.

For example, when R ⁵ is a halogenated or perhalogenated alkyl group having 1 to 20 carbon atoms (C _{1 to} C ₂₀ ), R ⁵ is represented by the general formula: —C _Z X ″ _{2Z + 1} . Here, z and X ″ are the same as defined above, and at least one of X ″ is a halogen atom (for example, a bromine atom, a chlorine atom, or a fluorine atom).

Here, the perhalogenated alkyl group is a group in which all X ″ are halogen atoms in the above general formula, and specific examples thereof include a trifluoromethyl group, a trichloromethyl group, —C ₇ F _15. Although _-C 11 _{F 23} are exemplified, but not limited to.

  Specific examples of the perhalogenated aryl group include, but are not limited to, a pentachlorophenyl group and a pentafluorophenyl group.

Examples of R ⁶ include —C (CH ₃ ) ₃ , —Si (CH ₃ ) ₃ , —CH (R ⁷ ) —O—CH ₂ CH ₃ , —CH (R ⁷ ) OC (CH ₃ ). ₃ and the cyclic group of the following chemical formula 4 and the like.

ここで、Ｒ^７は、水素原子、あるいは直鎖状または分岐状の炭素数１〜５（Ｃ_１〜Ｃ_５）のアルキル基を表す。

Here, R ⁷ represents a hydrogen atom or a linear or branched alkyl group having ₁ to ₅ carbon atoms (C _{1 to} C ₅ ).

  Examples of the alkyl group include methyl group, ethyl group, propyl group, i-propyl group, butyl group, i-butyl group, t-butyl, pentyl group, t-pentyl group, and neopentyl group.

  In the cyclic group represented by Chemical Formula 4, an ester bond is formed between the single bond extending from the ring structure and the acid substituent.

Specific examples of R ⁶ include, for example, a 1-methyl-1-cyclohexyl group, an isobornyl group, a 2-methyl-2-isobornyl group, a 2-methyl-2-adamantyl group, a tetrahydrofuranyl group, Examples thereof include a tetrahydropyranoyl group, a 3-oxocyclohexanoyl group, a mevalonic lactonyl group, a 1-ethoxyethyl group, and a 1-t-butoxyethyl group.

Other examples of R ⁶ include a dicyclopropylmethyl group (Dcpm) and a dimethylcyclopropylmethyl group (Dmcp) represented by the following chemical formula 5.

  Moreover, it can replace with said monomer for a monomer, or can also use a crosslinkable monomer (crosslinking agent) with said monomer. This crosslinkable monomer is a compound capable of causing a crosslinking reaction in the presence of a catalyst precursor described later.

  The use of the crosslinkable monomer has the following advantages. That is, since the crosslinkable monomer is polymerized faster, the time required for the formation (process) of the core layer 93 (optical waveguide 9) can be shortened. Moreover, since the crosslinkable monomer is difficult to evaporate even when heated, an increase in vapor pressure can be suppressed. Furthermore, since the crosslinkable monomer is excellent in heat resistance, the heat resistance of the core layer 93 can be improved.

  Among these, the crosslinkable norbornene-based monomer is a compound including a norbornene-based moiety (norbornene-based double bond) represented by Formula 2 (Structural Formula A).

  As the crosslinkable norbornene-based monomer, there are a compound of a continuous polycyclic ring system and a compound of a linked multicyclic ring system.

  Examples of the continuous polycyclic ring-based compound (continuous polycyclic ring-based crosslinkable norbornene-based monomer) include compounds represented by the following chemical formula (6).

［式中、Ｙは、メチレン（−ＣＨ_２−）基を表し、ｍは、０〜５の整数を表わす。ただし、ｍが０である場合、Ｙは、単結合である。］

[Wherein Y represents a methylene (—CH ₂ —) group, and m represents an integer of 0 to 5. However, when m is 0, Y is a single bond. ]

  For simplicity, norbornadiene is considered to be included in a continuous polycyclic ring system and includes a polymerizable norbornene double bond.

  Specific examples of this continuous polycyclic compound include, but are not limited to, compounds represented by the following chemical formula (7).

  On the other hand, examples of the linked polycyclic ring-based compound (linked polycyclic ring-based crosslinkable norbornene-based monomer) include compounds represented by the following formula 8.

［式中、ａは、それぞれ独立して、単結合または二重結合を表し、ｍは、それぞれ独立して、０〜５の整数を表し、Ｒ^９は、それぞれ独立して二価の炭化水素基、二価のエーテル基または二価のシリル基を表す。また、ｎは、０または１である。］

[Wherein, a independently represents a single bond or a double bond; m independently represents an integer of 0 to 5; and R ⁹ independently represents a divalent hydrocarbon. Represents a group, a divalent ether group or a divalent silyl group. N is 0 or 1. ]

  Here, the divalent substituent refers to a group having two bonds that can be bonded to the norbornene structure at the end.

Specific examples of the divalent hydrocarbon group (hydrocarbyl group) include an alkylene group represented by the general formula:-(C _d H _2d )-(d is preferably an integer of 1 to 10). And a divalent aromatic group (aryl group).

The divalent alkylene group is preferably a linear or branched alkylene group having 1 to 10 carbon atoms (C _{1 to} C ₁₀ ), such as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, Examples include a hexylene group, a heptylene group, an octylene group, a nonylene group, and a decylene group.

  The branched alkylene group is one in which a main chain hydrogen atom is substituted with a linear or branched alkyl group.

On the other hand, the divalent aromatic group is preferably a divalent phenyl group or a divalent naphthyl group.
The divalent ether group is a group represented by —R ¹⁰ —O—R ¹⁰ —.
Here, R ¹⁰ independently represents the same as R ⁹ .

  Specific examples of this linked polycyclic ring compound include compounds represented by the following chemical formula 9, chemical formula 10, chemical formula 11, chemical formula 12, chemical formula 13, and fluorine-containing compounds represented by chemical formulas 14 and 15 ( Fluorine-containing crosslinkable norbornene-based monomer), but is not limited thereto.

  The compound represented by the chemical formula 10 is dimethylbis [bicyclo [2.2.1] hept-2-ene-5-methoxy] silane, and is named dimethylbis (norbornenemethoxy) silane (“ Abbreviated as “SiX”).

［式中、ｎは、０〜４の整数を表す。］

[Wherein, n represents an integer of 0 to 4. ]

［式中、ｍおよびｎは、それぞれ、１〜４の整数を表す。］

[Wherein, m and n each represent an integer of 1 to 4. ]

  Among various crosslinkable norbornene monomers, dimethylbis (norbornenemethoxy) silane (SiX) is particularly preferable. SiX has a sufficiently low refractive index with respect to a norbornene-based polymer containing a repeating unit of alkylnorbornene and / or a repeating unit of aralkylnorbornene. For this reason, the refractive index of the irradiation region irradiated with actinic radiation, which will be described later, can be reliably lowered to form the cladding portion 95. Moreover, the refractive index difference between the core part 94 and the clad part 95 can be increased, and the characteristics (optical transmission performance) of the core layer 93 (optical waveguide 9) can be improved.

  In addition, you may make it use the above monomers individually or in arbitrary combinations.

  The catalyst precursor (second substance) is a substance capable of initiating the above-described monomer reaction (polymerization reaction, crosslinking reaction, etc.), and is a promoter (first substance) activated by irradiation with actinic radiation described later. It is a substance whose activation temperature changes by the action of.

  As the catalyst precursor (procatalyst), any compound may be used as long as the activation temperature changes (increases or decreases) with irradiation of actinic radiation. Those whose activation temperature decreases with irradiation are preferred. As a result, the core layer 93 (optical waveguide 9) can be formed by heat treatment at a relatively low temperature, and unnecessary heat is applied to the other layers, so that the characteristics (optical transmission performance) of the optical waveguide 9 are degraded. Can be prevented.

  As such a catalyst precursor, a catalyst precursor containing (mainly) at least one of the compounds represented by the following formulas (Ia) and (Ib) is preferably used.

［式Ｉａ、Ｉｂ中、それぞれ、Ｅ（Ｒ）_３は、第１５族の中性電子ドナー配位子を表し、Ｅは、周期律表の第１５族から選択される元素を表し、Ｒは、水素原子（またはその同位体の１つ）または炭化水素基を含む部位を表し、Ｑは、カルボキシレート、チオカルボキシレートおよびジチオカルボキシレートから選択されるアニオン配位子を表す。また、式Ｉｂ中、ＬＢは、ルイス塩基を表し、ＷＣＡは、弱配位アニオンを表し、ａは、１〜３の整数を表し、ｂは、０〜２の整数を表し、ａとｂとの合計は、１〜３であり、ｐおよびｒは、パラジウムカチオンと弱配位アニオンとの電荷のバランスをとる数を表す。］

[In the formulas Ia and Ib, E (R) ₃ represents a neutral electron donor ligand of group 15, respectively, E represents an element selected from group 15 of the periodic table, and R represents , Represents a moiety containing a hydrogen atom (or one of its isotopes) or a hydrocarbon group, and Q represents an anionic ligand selected from carboxylate, thiocarboxylate and dithiocarboxylate. In Formula Ib, LB represents a Lewis base, WCA represents a weakly coordinating anion, a represents an integer of 1 to 3, b represents an integer of 0 to 2, and a and b , P and r represent numbers that balance the charge of the palladium cation and the weakly coordinated anion. ]

Typical catalyst precursors according to Formula Ia include Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ , Pd (OAc) ₂ (P (Cy) ₃ ) ₂ , Pd (O ₂ CCMe ₃ ) ₂ (P (Cy) ₃ ) ₂ , Pd (OAc) ₂ (P (Cp) ₃ ) ₂ , Pd (O ₂ CCF ₃ ) ₂ (P (Cy) ₃ ) ₂ , Pd (O ₂ CC ₆ H ₅ ) ₃ (P (Cy) ₃ ) ₂ may be mentioned, but is not limited thereto. Here, Cp represents a cyclopentyl group, and Cy represents a cyclohexyl group.

  The catalyst precursor represented by the formula Ib is preferably a compound in which p and r are each selected from integers of 1 and 2.

Typical catalyst precursors according to such formula Ib include Pd (OAc) ₂ (P (Cy) ₃ ) ₂ . Here, Cy represents a cyclohexyl group, and Ac represents an acetyl group.

  These catalyst precursors can efficiently react with a monomer (in the case of a norbornene-based monomer, an efficient polymerization reaction, a crosslinking reaction, etc. by an addition polymerization reaction).

  In the state where the activation temperature is lowered (active latent state), the catalyst precursor has an activation temperature lower by about 10 to 80 ° C. (preferably about 10 to 50 ° C.) than the original activation temperature. Is preferred. Thereby, the refractive index difference between the core part 94 and the clad part 95 can be produced reliably.

Such a catalyst precursor includes (mainly) one containing at least one of Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ and Pd (OAc) ₂ (P (Cy) ₃ ) _2. Is preferred.

Hereinafter, Pd (OAc) ₂ (P (i-Pr) ₃ ) ₂ may be abbreviated as “Pd545”, and Pd (OAc) ₂ (P (Cy) ₃ ) ₂ may be abbreviated as “Pd785”. .

  The cocatalyst (first substance) is a substance that can be activated by irradiation with actinic radiation to change the activation temperature of the catalyst precursor (procatalyst) (the temperature at which the monomer reacts).

  As the cocatalyst (cocatalyst), any compound can be used as long as it has a molecular structure that changes (reacts or decomposes) when activated by irradiation with actinic radiation. A compound (photoinitiator) that decomposes upon irradiation with actinic radiation and generates a cation such as a proton or other cation and a weakly coordinated anion (WCA) that can be substituted with a leaving group of the catalyst precursor ( (Mainly) is preferably used.

Examples of the weak coordination anion include tetrakis (pentafluorophenyl) borate ion (FABA ⁻ ), hexafluoroantimonate ion (SbF ₆ ⁻ ), and the like.

  Examples of the cocatalyst (photoacid generator or photobase generator) include tetrakis (pentafluorophenyl) borate and hexafluoroantimonate represented by the following chemical formula 17, tetrakis (pentafluorophenyl) Examples include gallates, aluminates, antimonates, other borates, gallates, carboranes, halocarboranes, and the like.

  As a commercial product of such a promoter, for example, “RHODORSIL (registered trademark, the same applies hereinafter) PHOTOINITIATOR 2074 (CAS No. 178233-72-2) available from Rhodia USA, Cranberry, NJ "TAG-372R ((dimethyl (2- (2-naphthyl) -2-oxoethyl) sulfonium tetrakis (pentafluorophenyl) borate: CAS No. 193957) available from Toyo Ink Manufacturing Co., Ltd., Tokyo, Japan" -54-9)), "MPI-103 (CAS No. 87709-41-9)" available from Midori Chemical Co., Tokyo, Japan, available from Toyo Ink Manufacturing Co., Ltd., Tokyo, Japan "TAG-371 (CAS No. 193957-53-8 “TTBPS-TPFPB (tris (4-tert-butylphenyl) sulfonium tetrakis (pentapentafluorophenyl) borate)”, available from Toyo Gosei Co., Ltd., Tokyo, Midori Chemical Industries, Tokyo, Japan Examples thereof include “NAI-105 (CAS No. 85342-62-7)” available from a corporation.

  When RHODORSIL PHOTOINITIATOR 2074 is used as the cocatalyst (first substance), ultraviolet rays (UV light) are preferably used as actinic radiation (chemical rays) described later, and mercury lamps ( A high pressure mercury lamp) is preferably used. Thereby, ultraviolet rays (active radiation) having sufficient energy of less than 300 nm can be supplied to the layer 910, and RHODOLSIL PHOTOINITIATOR 2074 can be efficiently decomposed to generate the above-described cation and WCA.

  Moreover, you may make it add a sensitizer in the core layer forming material (varnish) 900 as needed.

  The sensitizer increases the sensitivity of the cocatalyst to actinic radiation, reduces the time and energy required for the activation (reaction or decomposition) of the cocatalyst, and the wavelength of the actinic radiation to a wavelength suitable for the activation of the cocatalyst. It has a function of changing the wavelength.

  Such a sensitizer is appropriately selected depending on the sensitivity of the promoter and the peak wavelength of absorption of the sensitizer, and is not particularly limited. For example, 9,10-dibutoxyanthracene (CAS No. 76275) is selected. 14-4) anthracenes, xanthones, anthraquinones, phenanthrenes, chrysenes, benzpyrenes, fluoranthenes, rubrenes, pyrenes, indanthrines, thioxanthen-9-ones (Thioxanthen-9-ones) and the like, and these are used alone or as a mixture.

  Specific examples of the sensitizer include 2-isopropyl-9H-thioxanthen-9-one, 4-isopropyl-9H-thioxanthen-9-one, 1-chloro-4-propoxythioxanthone, phenothiazine, and these Of the mixture.

  9,10-dibutoxyanthracene (DBA) can be obtained from Kawasaki Kasei Kogyo Co., Ltd., Kanagawa, Japan.

  The content of the sensitizer in the core layer forming material 900 is not particularly limited, but is preferably 0.01% by weight or more, more preferably 0.5% by weight or more, and 1% by weight or more. More preferably. In addition, it is preferable that an upper limit is 5 weight% or less.

  Furthermore, an antioxidant can be added to the core layer forming material 900. Thereby, generation | occurrence | production of an undesired free radical and the natural oxidation of the polymer 915 can be prevented. As a result, the characteristics of the obtained core layer 93 (optical waveguide 9) can be improved.

  Examples of the antioxidant include Ciba (registered trademark, the same applies hereinafter) IRGANOX (registered trademark, the same applies hereinafter) 1076 and Ciba IRGAFOS (registered trademark, available) from Ciba Specialty Chemicals of Tarrytown, New York. The same applies hereinafter.) 168 is preferably used.

  Other antioxidants include, for example, Ciba Irganox (registered trademark, hereinafter the same) 129, Ciba Irganox 1330, Ciba Irganox 1010, Ciba Cyanox (registered trademark, the same shall apply hereinafter) 1790, Ciba Irg. (Registered trademark) 3114, Ciba Irganox 3125, etc. can also be used.

  Note that such an antioxidant can be omitted, for example, when the layer 910 is not exposed to oxidation conditions or when the exposure period is extremely short.

  Examples of the solvent used for preparing the core layer forming material (varnish) 900 include diethyl ether, diisopropyl ether, 1,2-dimethoxyethane (DME), 1,4-dioxane, tetrahydrofuran (THF), tetrahydropyran (THP). ), Ether solvents such as anisole, diethylene glycol dimethyl ether (diglyme), diethylene glycol ethyl ether (carbitol), cellosolv solvents such as methyl cellosolve, ethyl cellosolve, phenyl cellosolve, aliphatic hydrocarbons such as hexane, pentane, heptane, cyclohexane Solvent, aromatic hydrocarbon solvent such as toluene, xylene, benzene, mesitylene, aromatic heterocyclic compound solvent such as pyridine, pyrazine, furan, pyrrole, thiophene, methylpyrrolidone, Amide solvents such as N, N-dimethylformamide (DMF) and N, N-dimethylacetamide (DMA), halogen compound solvents such as dichloromethane, chloroform and 1,2-dichloroethane, ethyl acetate, methyl acetate, ethyl formate, etc. Examples thereof include various organic solvents such as ester solvents, sulfur compound solvents such as dimethyl sulfoxide (DMSO) and sulfolane, and mixed solvents containing these.

  As a method for removing (desolving) the solvent from the liquid film formed on the support substrate 951, for example, natural drying, heating, leaving under reduced pressure, or blowing of an inert gas (blow) or the like is performed. Examples include forced drying.

  As described above, the layer 910 that is a film-like solidified product (or cured product) of the core layer forming material 900 is formed on the support substrate 951.

  At this time, the layer (dry film of PITDM) 910 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 and monomers that are uniformly dispersed (distributed) in the layer 910.

  [2A] Next, a mask (masking) 935 in which an opening (window) 9351 is formed is prepared, and the active radiation 930 is irradiated to the layer 910 through the mask 935 (see FIG. 12B).

  Hereinafter, a case where a monomer having a refractive index lower than that of the polymer 915 is used as a monomer, and a catalyst precursor whose activation temperature decreases with irradiation of the active radiation 930 will be described as an example.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

  Therefore, in the example shown here, an opening (window) 9351 equivalent to the pattern of the clad portion 95 to be formed is formed in the mask 935. This opening 9351 forms a transmission part through which the active radiation 930 to be irradiated passes.

  The mask 935 may be formed in advance (separately formed) (for example, plate-shaped) or may be formed on the layer 910 by, for example, a vapor deposition method or a coating method.

  Preferred examples of the mask 935 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. 12B, an opening (window) 9351 equivalent to the pattern of the clad portion 95 to be formed shows that the mask has been partially removed along the pattern of the non-irradiated region 940 of the active radiation 930. However, when using a photomask made of quartz glass, PET base material, or the like, a photomask provided with a shielding portion of active radiation 930 made of a shielding material made of metal such as chromium is used. You can also. In this mask, the part other than the shielding part is the window (transmission part).

  The actinic radiation 930 to be used is not particularly limited as long as it can cause a photochemical reaction (change) to the promoter. For example, in addition to visible light, ultraviolet light, infrared light, and laser light, an electron beam or X Lines or the like can also be used.

  Among these, the actinic radiation 930 is appropriately selected depending on the type of co-catalyst and the type of sensitizer when it contains a sensitizer, and is not particularly limited, but has a peak wavelength in the range of 200 to 450 nm. It is preferable to have it. Thereby, a cocatalyst can be activated comparatively easily.

The irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about ^{0.2~6J / cm 2, 0.2~3J / cm} 2 of about More preferably. Thereby, a promoter can be activated reliably.

  The constituent material of the mask 935 is appropriately selected according to the active radiation 930 to be irradiated. Specifically, the constituent material of the mask 935 is a material that can block the active radiation 930. Any known material may be used for the mask 935 as long as it has such characteristics.

  When the layer 910 is irradiated with the active radiation 930 through the mask 935, the cocatalyst (first substance: cocatalyst) present in the irradiation region 925 irradiated with the active radiation 930 reacts by the action of the active radiation 930. (Binding) or decomposition to release (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  These cations and weakly coordinating anions cause a change (decomposition) in the molecular structure of the catalyst precursor (second substance: procatalyst) present in the irradiation region 925, and this changes the active latent state (latent potential). Active state).

  Here, the catalyst precursor in the active latent state (or the latent active state) has an activation temperature lower than the original activation temperature, but there is no temperature increase, that is, at about room temperature, the irradiation region. It refers to a catalyst precursor that is in a state where a monomer reaction cannot occur within 925.

  Therefore, even after irradiation with the active radiation 930, if the layer 910 is stored at, for example, about −40 ° C., the state can be maintained without causing a monomer reaction. For this reason, the core layer 93 can be obtained by preparing a plurality of layers 910 after irradiation with the active radiation 930 and subjecting them to heat treatment at once, which is highly convenient.

  Note that in the case where light having high directivity such as laser light is used as the active radiation 930, the use of the mask 935 may be omitted.

[3A] Next, the layer 910 is subjected to heat treatment (first heat treatment).
Thereby, in the irradiation region 925, the catalyst precursor in the active latent state is activated (becomes active), and monomer reaction (polymerization reaction or cross-linking reaction) occurs.

  As the monomer reaction proceeds, the monomer concentration in the irradiation region 925 gradually decreases. As a result, a difference in monomer concentration occurs between the irradiated region 925 and the unirradiated region 940, and in order to eliminate this, the monomer diffuses from the unirradiated region 940 (monomer diffusion) and collects in the irradiated region 925. come.

  As a result, in the irradiated region 925, the monomer and its reaction product (polymer, cross-linked structure or branched structure) increase, and the structure derived from the monomer greatly affects the refractive index of the region, so that the first refraction The second refractive index lower than the refractive index. As the monomer polymer, an addition (co) polymer is mainly produced.

  On the other hand, in the unirradiated region 940, the amount of monomer decreases due to the diffusion of the monomer from the region to the irradiated region 925, so that the influence of the polymer 915 greatly appears on the refractive index of the region, and the first refraction The third refractive index is higher than the refractive index.

  In this way, a refractive index difference (second refractive index <third refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed (see FIG. 12-C).

  Although the heating temperature in this heat processing is not specifically limited, It is preferable that it is about 30-80 degreeC, and it is more preferable that it is about 40-60 degreeC.

  The heating time is preferably set so that the reaction of the monomer in the irradiation region 925 is almost completed. Specifically, the heating time is preferably about 0.1 to 2 hours, and 0.1 to 1 hour. More preferred is the degree.

  Here, the core section 94 is formed in a square shape such as a square or a rectangle (rectangle) as shown in the figure, but the width and the height are preferably about 1 to 200 μm, respectively. More preferably, it is about 5-100 micrometers, More preferably, it is about 10-60 micrometers.

[4A] Next, the layer 910 is subjected to a second heat treatment.
As a result, the catalyst precursor remaining in the unirradiated region 940 and / or the irradiated region 925 is activated (activated) directly or with activation of the cocatalyst, thereby causing the regions 925 and 940 to be activated. The remaining monomer is reacted.

  In this way, by reacting the monomers remaining in the regions 925 and 940, the core portion 94 and the clad portion 95 obtained can be stabilized.

  The heating temperature in the second heat treatment is not particularly limited as long as it can activate the catalyst precursor or the cocatalyst, but is preferably about 70 to 100 ° C, and is about 80 to 90 ° C. Is more preferable.

  The heating time is preferably about 0.5 to 2 hours, more preferably about 0.5 to 1 hour.

[5A] Next, the layer 910 is subjected to a third heat treatment.
Thereby, the internal stress generated in the obtained core layer 93 can be reduced, and the core portion 94 and the cladding portion 95 can be further stabilized.

  The heating temperature in the third heat treatment is preferably set to 20 ° C. or more higher than the heating temperature in the second heat treatment, specifically, preferably about 90 to 180 ° C., 120 to 160 ° C. More preferred is the degree.

The heating time is preferably about 0.5 to 2 hours, more preferably about 0.5 to 1 hour.
The core layer 93 is obtained through the above steps.

  For example, when a sufficient refractive index difference is obtained between the core portion 94 and the clad portion 95 in a state before the second heat treatment or the third heat treatment is performed, this step is performed. [5A] and the step [4A] may be omitted.

  [6A] Next, the cladding layer 91 (92) is formed on the support substrate 952 (see FIG. 12-D).

  As a method for forming the clad layer 91 (92), a method in which a varnish containing a clad material (clad layer forming material) is applied and cured (solidified), and a method in which a curable monomer composition is applied and cured (solidified). Any method may be used.

When the clad layer 91 (92) 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.
As the support substrate 952, a substrate similar to the support substrate 951 can be used.

  Examples of the constituent material of the clad layer 91 (92) include acrylic resins, methacrylic resins, polycarbonate, polystyrene, epoxy resins, polyamides, polyimides, polybenzoxazoles, benzocyclobutene resins, and norbornene resins. These resins can be used, and one or more of these can be used in combination (polymer alloy, polymer blend (mixture), copolymer, composite (laminate), etc.).

  Of these, epoxy resins, polyimides, polybenzoxazoles, cyclic olefin resins such as benzocyclobutene resins and norbornene resins, and those containing them (mainly) in terms of particularly excellent heat resistance It is preferable to use, and particularly, those mainly composed of norbornene-based resins (norbornene-based polymers) are preferable.

  Since the norbornene-based polymer is excellent in heat resistance, in the optical waveguide 9 that uses this as a constituent material of the cladding layer 91 (92), when the conductor layer is formed on the optical waveguide 9, the conductor layer is processed to form a wiring. At this time, even when the optical element is heated to mount it, the clad layer 91 (92) can be prevented from being softened and deformed.

  Moreover, since it has high hydrophobicity, it is possible to obtain the clad layer 91 (92) that is less likely to undergo dimensional changes due to water absorption.

  Norbornene-based polymers or norbornene-based monomers that are raw materials thereof are also preferable because they are relatively inexpensive and easily available.

  Furthermore, when a material mainly composed of a norbornene-based polymer is used as the material of the clad layer 91 (92), the clad layers 91 and 92 and the core layer 93 are excellent in resistance to deformation such as bending, even when repeatedly bent and deformed. The delamination is difficult to occur, and the occurrence of microcracks in the clad layers 91 and 93 is also prevented. In addition, since it is the same kind of material that is suitably used as the constituent material of the core layer 93, the adhesion with the core layer 93 is further increased, and delamination between the clad layer 91 (92) and the core layer 93 is achieved. Can be prevented. For this reason, the optical transmission performance of the optical waveguide 9 is maintained, and the optical waveguide 9 having excellent durability can be obtained.

  Examples of such norbornene-based polymers include (1) addition (co) polymers of norbornene monomers obtained by addition (co) polymerization of norbornene monomers, and (2) norbornene monomers and ethylene or α-olefins. (3) addition polymers such as addition copolymers with norbornene-type monomers and non-conjugated dienes, and other monomers as required, (4) ring opening of norbornene-type monomers ( A (co) polymer, and a resin obtained by hydrogenating the (co) polymer if necessary, (5) a ring-opening copolymer of a norbornene-type monomer and ethylene or α-olefins, and ( (Co) polymer hydrogenated resin, (6) ring-opening copolymer of norbornene type monomer and non-conjugated diene or other monomer, and (co) polymerization if necessary And a ring-opening polymer such as a polymer obtained by hydrogenating the body. Examples of these polymers include random copolymers, block copolymers, and alternating copolymers.

  These norbornene-based polymers include, for example, ring-opening metathesis polymerization (ROMP), combination of ROMP and hydrogenation reaction, polymerization by radical or cation, polymerization using a cationic palladium polymerization initiator, and other polymerization initiators ( For example, it can be obtained by any known polymerization method such as polymerization using a polymerization initiator of nickel or another transition metal).

  Among these, as the norbornene-based polymer, an addition (co) polymer is preferable. This is preferable because it is rich in transparency, heat resistance and flexibility.

  In particular, the norbornene-based polymer preferably includes a norbornene repeating unit having a substituent containing a polymerizable group or a norbornene repeating unit having a substituent containing an aryl group.

  By including a norbornene repeating unit having a substituent containing a polymerizable group, in the cladding layer 91 (92), the polymerizable groups of at least some of the norbornene-based polymers are crosslinked directly or via a crosslinking agent. be able to. Depending on the type of polymerizable group, the type of crosslinking agent, the type of polymer used for the core layer 93, the norbornene-based polymer and the polymer used for the core layer 93 can be cross-linked. In other words, it is preferable that at least a part of the norbornene-based polymer is crosslinked at the polymerizable group.

  As a result, the strength of the clad layer 91 (92) itself and the adhesion between the clad layer 91 (92) and the core layer 93 can be further improved.

  Examples of the norbornene repeating unit containing a polymerizable group include a norbornene repeating unit having a substituent containing an epoxy group, a norbornene repeating unit having a substituent containing a (meth) acryl group, and an alkoxysilyl group. At least one of the repeating units of norbornene having a substituent to be included is preferable. These polymerizable groups are preferable because of their high reactivity among various polymerizable groups.

  Moreover, if the thing containing 2 or more types of norbornene repeating units containing such a polymeric group is used, a crosslinking density can be improved further and the said effect will become more remarkable.

  On the other hand, by including a norbornene repeating unit having a substituent containing an aryl group, the aryl group has extremely high hydrophobicity, so that the dimensional change due to water absorption of the cladding layer 91 (92) can be more reliably prevented. it can. In addition, since the aryl group is excellent in fat solubility (lipophilicity) and has a high affinity with the polymer used in the core layer 93 as described above, an interlayer between the clad layer 91 (92) and the core layer 93 is used. Separation can be prevented more reliably, and an optical waveguide 9 with higher durability can be obtained.

  Furthermore, the norbornene-based polymer preferably contains an alkylnorbornene repeating unit. The alkyl group may be linear or branched.

  By including the repeating unit of alkyl norbornene, the norbornene-based polymer has high flexibility, so that high flexibility (flexibility) can be imparted to the clad layers 91 and 92 (optical waveguide 9).

  A norbornene-based polymer containing an alkylnorbornene repeating unit is also preferable because of its excellent transmittance for light in the wavelength region as described above (particularly in the wavelength region near 850 nm).

  The norbornene-based polymer used for the clad layer 91 (92) is preferably a polymer having a relatively low refractive index, but generally contains a norbornene repeating unit having a substituent containing an aryl group, the refractive index is generally However, an increase in the refractive index can be prevented by including an alkyl norbornene repeating unit.

  Therefore, as the norbornene-based polymer used for the clad layer 91 (92), those represented by the following chemical formulas 18 to 21 and chemical formula 25 are preferable.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、ａは、０〜３の整数を表し、ｂは、１〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein R represents an alkyl group having 1 to 10 carbon atoms, a represents an integer of 0 to 3, b represents an integer of 1 to 3, and p / q is 20 or less. ]

  Among the norbornene-based polymers represented by Chemical formula 18, a compound in which R is an alkyl group having 4 to 10 carbon atoms and a and b are each 1, for example, a copolymer of butylbornene and methylglycidyl ether norbornene A copolymer of hexyl norbornene and methyl glycidyl ether norbornene, a copolymer of decyl norbornene and methyl glycidyl ether norbornene, and the like are preferable.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｒ^１は、水素原子またはメチル基を表し、ａは、０〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, R ¹ represents a hydrogen atom or a methyl group, a represents an integer of 0 to 3, and p / q is 20 or less. ]

  Among the norbornene-based polymers represented by Chemical formula 19, compounds in which R is an alkyl group having 4 to 10 carbon atoms and a is 1, for example, butylbornene and 2- (5-norbornenyl) methyl acrylate And a copolymer of hexylnorbornene and 2- (5-norbornenyl) methyl acrylate, a copolymer of decylnorbornene and 2- (5-norbornenyl) methyl acrylate, and the like.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｘは、それぞれ独立して、炭素数１〜３のアルキル基を表し、ａは、０〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, X represents each independently an alkyl group having 1 to 3 carbon atoms, a represents an integer of 0 to 3, and p / q is 20 or less. ]

  Among the norbornene-based polymers represented by Chemical Formula 20, in particular, compounds in which R is an alkyl group having 4 to 10 carbon atoms, a is 1 or 2, and X is a methyl group or an ethyl group, such as butylbornene Copolymer of norbornenylethyltrimethoxysilane, copolymer of hexylnorbornene and norbornenylethyltrimethoxysilane, copolymer of decylnorbornene and norbornenylethyltrimethoxysilane, copolymer of butylbornene and triethoxysilylnorbornene, hexyl Copolymers of norbornene and triethoxysilyl norbornene, copolymers of decyl norbornene and triethoxysilyl norbornene, copolymers of butylbornene and trimethoxysilyl norbornene, hexyl norbornene and tri Copolymers of butoxy silyl norbornene copolymer and the like of decyl norbornene and trimethoxysilyl norbornene are preferred.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ａ^１およびＡ^２は、それぞれ独立して、下記化２２〜２４で表される置換基を表すが、同時に同一の置換基であることはない。また、ｐ／ｑ＋ｒが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, and A ¹ and A ² each independently represent a substituent represented by the following chemical formulas 22 to 24, but at the same time, the same substituent Never. Moreover, p / q + r is 20 or less. ]

［式中、ａは、０〜３の整数を表し、ｂは、１〜３の整数を表す。］

[Wherein, a represents an integer of 0 to 3, and b represents an integer of 1 to 3. ]

［式中、Ｒ^１は、水素原子またはメチル基を表し、ａは、０〜３の整数を表す。］

[Wherein, R ¹ represents a hydrogen atom or a methyl group, and a represents an integer of 0 to 3. ]

［式中、Ｘは、それぞれ独立して、炭素数１〜３のアルキル基を表し、ａは、０〜３の整数を表す。］

[In formula, X represents a C1-C3 alkyl group each independently, and a represents the integer of 0-3. ]

  As the norbornene-based polymer represented by Chemical formula 21, for example, any of butylbornene, hexylnorbornene or decylnorbornene, 2- (5-norbornenyl) methyl acrylate, norbornenylethyltrimethoxysilane, triethoxysilyl Terpolymers with either norbornene or trimethoxysilyl norbornene, terpolymers of either butylbornene, hexyl norbornene or decyl norbornene with 2- (5-norbornenyl) methyl acrylate and methylglycidyl ether norbornene, butylbornene, hexyl norbornene or One of decyl norbornene, methyl glycidyl ether norbornene, norbornenyl ethyl trimethoxysilane, triethoxysilyl norbornene Terpolymers, etc. with either Nen or trimethoxysilyl norbornene.

［式中、Ｒは、炭素数１〜１０のアルキル基を表し、Ｒ^２は、水素原子、メチル基またはエチル基を表し、Ａｒは、アリール基を表し、Ｘ^１は、酸素原子またはメチレン基を表し、Ｘ^２は、炭素原子またはシリコン原子を表し、ａは、０〜３の整数を表し、ｃは、１〜３の整数を表し、ｐ／ｑが２０以下である。］

[Wherein, R represents an alkyl group having 1 to 10 carbon atoms, R ² represents a hydrogen atom, a methyl group or an ethyl group, Ar represents an aryl group, and X ¹ represents an oxygen atom or a methylene group. X ² represents a carbon atom or a silicon atom, a represents an integer of 0 to 3, c represents an integer of 1 to 3, and p / q is 20 or less. ]

Of the norbornene polymers represented by Chemical Formula 25, in particular, R is an alkyl group having 4 to 10 carbon atoms, X ¹ is an oxygen atom, X ² is a silicon atom, Ar is a phenyl group, and R ² is methyl. A group in which a is 1 and c is 2, for example, a copolymer of butylbornene and diphenylmethylnorbornenemethoxysilane, a copolymer of hexylnorbornene and diphenylmethylnorbornenemethoxysilane, a copolymer of decylnorbornene and diphenylmethylnorbornenemethoxysilane, etc. Or R is an alkyl group having 4 to 10 carbon atoms, X ¹ is a methylene group, X ² is a carbon atom, Ar is a phenyl group, R ² is a hydrogen atom, a is 0, and c is 1, for example, , A copolymer of butylbornene and phenylethylnorbornene, hexylnorbornene and Copolymers of E sulfonyl ethyl norbornene copolymer, etc. of decyl norbornene and phenyl ethyl norbornene are preferred.

  Moreover, although p / q or p / q + r should just be 20 or less, it is preferable that it is 15 or less, and about 0.1-10 is more preferable. Thereby, the effect including the repeating unit of multiple types of norbornene is exhibited.

  The norbornene-based polymer as described above has a relatively low refractive index in addition to the above-described characteristics. By forming the clad layer 91 (92) using such a norbornene-based polymer as a main material, the optical waveguide 9 The optical transmission performance can be further improved.

  When the norbornene-based polymer includes a norbornene repeating unit having a substituent containing a (meth) acryl group, the (meth) acryl groups can be crosslinked (polymerized) relatively easily by heating. By mixing a radical generator in the cladding layer forming material, the cross-linking reaction between (meth) acrylic groups can be promoted.

  As the radical generator, for example, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane and the like are preferably used. .

  In addition, when the norbornene-based polymer includes a norbornene repeating unit having a substituent containing an epoxy group or a norbornene repeating unit having a substituent containing an alkoxysilyl group, in order to directly crosslink these polymerizable groups In the clad layer forming material, the same kind of substance (photoacid generator or photobase generator) as the above-mentioned promoter is mixed, and the epoxy group or alkoxysilyl group is crosslinked by the action of this substance. Just do it.

  On the other hand, in order to crosslink epoxy groups, (meth) acrylic groups, or alkoxysilyl groups via a crosslinking agent, it corresponds to each polymerizable group as a crosslinking agent in the cladding layer forming material. A compound having at least one polymerizable group may be mixed.

  As the crosslinking agent having an epoxy group, for example, 3-glycidoxypropyltrimethoxysilane (γ-GPS), silicone epoxy resin, and the like are preferably used.

As a crosslinking agent having a (meth) acryl group, for example, 3-methacryloxypropyltrimethoxysilane tricyclo [5.2.1.0 ^2,6 ] decane dimethanol diacrylate, tripropylene glycol diacrylate and the like are preferable. Used for.

  As the crosslinking agent having an alkoxysilyl group, for example, a silane coupling agent such as 3-glycidoxypropyltrimethoxysilane or 3-aminopropyltrimethoxysilane is preferably used.

  The crosslinking reaction between these polymerizable groups may be performed at the final stage of this step [6A], or may be performed after obtaining the optical waveguide 9 in the next step [7A].

  Further, various additives may be added (mixed) to the cladding layer forming material.

  For example, the monomer, the catalyst precursor, and the co-catalyst mentioned in the material for forming the core layer may be mixed in the material for forming the cladding layer. Thereby, in the clad layer 91 (92), the refractive index of the clad layer 91 (92) can be changed by reacting the monomer in the same manner as described above.

  In particular, when a monomer containing a crosslinkable monomer is used as the monomer, at least a part of the norbornene-based polymer in the clad layer 91 (92) can be crosslinked via the crosslinkable monomer. Depending on the type of crosslinking agent, the type of polymer used for the core layer 93, the norbornene-based polymer and the polymer used for the core layer 93 can be cross-linked.

  In this case, since it is not required to provide a difference in refractive index in the clad layer 91 (92), it is possible to omit the promoter and use a catalyst precursor that is easily activated by heating.

Examples of such catalyst precursors include [Pd (PCy ₃ ) ₂ (O ₂ CCH ₃ ) (NCCH ₃ )] tetrakis (pentafluorophenyl) borate, [2-methylly Pd (PCy3) 2] tetrakis (pentafluorophenyl). ) Borate, [Pd (PCy3) 2H (NCCH3)] tetrakis (pentafluorophenyl) borate, [Pd (P (iPr) 3) 2 (OCOCH3) (NCCH3)] tetrakis (pentafluorophenyl) borate, and the like.

  Examples of other additives include the antioxidants described above. By mixing the antioxidant, it is possible to prevent deterioration of the clad material (norbornene polymer) due to oxidation.

As described above, the clad layer 91 (92) is formed on the support substrate 952.
The average thickness of the clad layers 91 and 92 is preferably about 0.1 to 1.5 times the average thickness of the core layer 93, more preferably about 0.3 to 1.25 times, Specifically, the average thickness of the clad layers 91 and 92 is not particularly limited, but it is usually preferably about 1 to 200 μm, more preferably about 5 to 100 μm, and about 10 to 60 μm. More preferably. Thereby, the function as a clad layer is suitably exhibited while preventing the optical waveguide 9 from becoming unnecessarily large (pressure film).

  [7A] Next, the core layer 93 is peeled from the support substrate 951, and the core layer 93 is sandwiched between the support substrate 952 on which the cladding layer 91 is formed and the support substrate 952 on which the cladding layer 92 is formed ( (See FIG. 12-E).

Then, as indicated by an arrow in FIG. 12E, pressure is applied from the upper surface side of the support substrate 952 on which the cladding layer 92 is formed, and the cladding layers 91 and 92 and the core layer 93 are pressure bonded.
Thereby, the clad layers 91 and 92 and the core layer 93 are joined and integrated.

  Further, this crimping operation is preferably performed under heating. The heating temperature is appropriately determined depending on the constituent materials of the clad layers 91 and 92 and the core layer 93, and is usually preferably about 80 to 200 ° C, more preferably about 120 to 180 ° C.

  Next, the support substrate 952 is peeled off and removed from the cladding layers 91 and 92, respectively. Thereby, the optical waveguide 9 is obtained.

  In a preferable example of such an optical waveguide 9, in the core layer 93, the core portion 94 is configured with the first norbornene-based material as a main material, and the cladding portion 95 has a lower refractive index than the first norbornene-based material. 2 is composed mainly of a norbornene-based polymer having a refractive index lower than that of the first norbornene-based material (core portion 94 of the core layer 93). The

  The first norbornene-based material and the second norbornene-based material both contain the same norbornene-based polymer, but contain a reaction product of a norbornene-based monomer having a refractive index different from that of the norbornene-based polymer. Due to the different amounts, the refractive indices are different from each other.

  Since the norbornene-based polymer has high transparency, the optical waveguide 9 having such a configuration can provide high optical transmission performance.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. 9, even when deformation such as bending occurs, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 hardly occur. It is also possible to prevent micro cracks from occurring. As a result, the optical transmission performance of the optical waveguide 9 is maintained.

  Further, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 9 having such a configuration has excellent durability.

  In addition, since the optical waveguide 9 can be imparted with high heat resistance and high hydrophobicity, the conductor layer can be reliably formed by adopting various methods as described above while preventing deterioration (deterioration) of its characteristics. can do. In particular, even when the conductor layer is formed so as to overlap the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time.

<Second production method>
Next, a second manufacturing method of the optical waveguide 9 will be described.

  Hereinafter, the second manufacturing method will be described, but the description will focus on differences from the first manufacturing method, and description of similar matters will be omitted.

  In the second manufacturing method, the composition of the core layer forming material 900 is different, and the rest is the same as the first manufacturing method.

That is, the core layer forming material 900 used in the second production method is a release agent (substance) that is activated by irradiation with actinic radiation and the action of the release agent activated by branching from the main chain and the main chain. Thus, at least a part of the molecular structure contains a polymer 915 having a leaving group (leaving pendant group) that can leave from the main chain.
As the releasing agent, the same promoter as that mentioned in the first production method can be used.

  Examples of the polymer 915 used in the second production method include those obtained by substituting the substituents of the polymer 915 exemplified in the first production method with a leaving group, and polymers 915 exemplified in the first production method. The thing which introduce | transduced the leaving group is mentioned.

  The refractive index of the polymer 915 changes (increases or decreases) due to the leaving (cleavage) of the leaving group.

  The leaving group may be any of those leaving by the action of a cation, anion or free radical, that is, any of an acid (cation) leaving group, a base (anion) leaving group, and a free radical leaving group. Although it is good, it is preferably a group capable of leaving by the action of a cation (proton) (acid group leaving group).

  As the acid leaving group, those having at least one of an —O— structure, an —Si—aryl structure and an —O—Si— structure in its molecular structure are preferable. Such an acid leaving group is released relatively easily by the action of a cation.

  Among these, as the acid leaving group that causes a decrease in the refractive index of the polymer 915 by leaving, at least one of a -Si-diphenyl structure and a -O-Si-diphenyl structure is preferable.

  In addition, as a free radical leaving group which leaves | separates by the effect | action of a free radical, the substituent etc. which have an acetophenone structure at the terminal are mentioned, for example.

  The polymer 915 is preferably a norbornene polymer for the same reason as described in the first production method, and more preferably a norbornene polymer containing a repeating unit of alkyl (particularly hexyl) norbornene. preferable.

  In consideration of the above, as the polymer 915 whose refractive index decreases due to leaving group leaving, a homopolymer of diphenylmethylnorbornenemethoxysilane or a copolymer of hexylnorbornene and diphenylmethylnorbornenemethoxysilane is preferably used. .

  Hereinafter, as an example, a case where the polymer 915 has a refractive index that decreases due to the removal of a leaving group (particularly, an acid leaving group) will be described.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

[1B] A step similar to the step [1A] is performed.
At this time, the layer (dry film of PITDM) 910 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 that is uniformly dispersed (distributed) in the layer 910.

[2B] A step similar to the step [2A] is performed.
When the layer 910 is irradiated with the actinic radiation 930 through the mask 935, the release agent present in the irradiation region 925 irradiated with the actinic radiation 930 reacts (bonds) or decomposes by the action of the actinic radiation 930, and becomes a cation. Liberate (generate) protons (or other cations) and weakly coordinating anions (WCA).

  Then, the cation causes the leaving group itself to leave the main chain, or cleaves from the middle of the molecular structure of the leaving group (photo bleach).

  As a result, in the irradiated region 925, the number of leaving groups in a complete state is decreased as compared with the unirradiated region 940, and the second refractive index is lower than the first refractive index. At this time, the refractive index of the unirradiated region 940 is maintained at the first refractive index.

  In this way, a refractive index difference (second refractive index <first refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed.

In this case, the irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about 0.3~6J / cm ^2, 0.6~6J / More preferably, it is about cm ² . Thereby, a release agent can be activated reliably.

[3B] Next, the layer 910 is subjected to heat treatment.
As a result, the leaving group detached (cut) from the polymer 915 is removed from the irradiated region 925 or rearranged or cross-linked in the polymer 915.

  Further, at this time, it is considered that a part of the leaving group remaining in the cladding part 95 (irradiation region 925) is further detached (cut).

  Therefore, the refractive index difference between the core portion 94 and the cladding portion 95 can be further increased by performing such heat treatment.

  Although the heating temperature in this heat processing is not specifically limited, It is preferable that it is about 70-195 degreeC, and it is more preferable that it is about 85-150 degreeC.

  Further, the heating time is set so as to sufficiently remove the leaving group detached (cut) from the irradiation region 925, and is not particularly limited, but is preferably about 0.5 to 3 hours, More preferably, it is about 2 hours.

  For example, when a sufficient refractive index difference is obtained between the core portion 94 and the cladding portion 95 in a state before the heat treatment, this step [3B] may be omitted. .

Moreover, the process of 1 time or several times of heat processing (for example, about 150-200 degreeC x about 1 to 8 hours) can also be added as needed.
The core layer 93 is obtained through the above steps.

[4B] A step similar to the step [6A] is performed.
[5B] A step similar to the step [7A] is performed.

The optical waveguide 9 is completed as described above.
In a preferred example of such an optical waveguide 9, the core layer 93 is made of a norbornene-based material as a main material, and the cladding layers 91 and 92 are made of a norbornene-based polymer having a refractive index lower than that of the core portion 94 of the core layer 93. Constructed as the main material.

  The core portion 94 and the clad portion 95 are mainly composed of a norbornene-based polymer having a main chain and a main chain branched from the main chain and having a leaving group capable of leaving at least a part of the molecular structure from the main chain. The core part 94 and the clad part 95 have different refractive indexes due to the difference in the number of leaving groups bonded to the main chain.

  Since the norbornene-based polymer has high transparency, the optical waveguide 9 having such a configuration can provide high optical transmission performance.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. 9, even when deformation such as bending occurs, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 hardly occur. It is also possible to prevent micro cracks from occurring. As a result, the optical transmission performance of the optical waveguide 9 is maintained.

  Further, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 9 having such a configuration has excellent durability.

  In addition, since the optical waveguide 9 can be imparted with high heat resistance and high hydrophobicity, the conductor layer can be reliably formed by adopting various methods as described above while preventing deterioration (deterioration) of its characteristics. can do. In particular, even when the conductor layer is formed so as to overlap the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time.

  In particular, according to the second manufacturing method, at least actinic radiation may be used, and the core layer 93 can be formed by an extremely simple process.

<Third production method>
Next, the 3rd manufacturing method of the optical waveguide 9 is demonstrated.

  Hereinafter, the third manufacturing method will be described, but the description will focus on differences from the first and second manufacturing methods, and the description of the same matters will be omitted.

  In the third manufacturing method, a combination of the core layer forming materials used in the first and second manufacturing methods is used as the core layer forming material 900. Otherwise, the first or second manufacturing method is used. It is the same as the method.

  That is, the core layer forming material 900 used in the third manufacturing method includes a polymer 915 having a leaving group as described above, a monomer, a promoter (first substance), and a catalyst precursor (second Substance). The cocatalyst is the same as the release agent in the second production method, and has a function of releasing the release agent.

  In such a core layer forming material 900, the refractive index difference between the core portion 94 and the clad portion 95 is more increased in the obtained core layer 93 due to the combination of the selected leaving group and the selected monomer. It becomes possible to adjust in stages.

  As described above, a monomer having a refractive index lower than that of the polymer 915 is used as a monomer, and a catalyst precursor whose activation temperature is reduced with irradiation of the active radiation 930 is used as a polymer 915. If a material whose refractive index is lowered by the removal of the leaving group is used, the irradiation region 925 can be used as the cladding portion 95, and the core layer 93 having a very large refractive index difference from the core portion 94 can be obtained.

  Hereinafter, a case where such a combination of the polymer 915, the monomer, and the catalyst precursor is used will be described as an example.

  That is, in the example shown here, the irradiation region 925 of the active radiation 930 becomes the clad portion 95.

[1C] A step similar to the step [1A] is performed.
At this time, the layer (dry film of PITDM) 910 has a first refractive index (RI). This first refractive index is due to the action of the polymer 915 and monomers that are uniformly dispersed (distributed) in the layer 910.

[2C] A step similar to the step [2A] is performed.
When the layer 910 is irradiated with the active radiation 930 through the mask 935, the cocatalyst (first substance: cocatalyst) present in the irradiation region 925 irradiated with the active radiation 930 reacts by the action of the active radiation 930. Alternatively, it decomposes to liberate (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  These cations and weakly coordinating anions cause a change (decomposition) in the molecular structure of the catalyst precursor (second substance: procatalyst) present in the irradiation region 925, and this changes the active latent state (latent potential). Active state).

  In addition, the cation causes the leaving group itself to leave the main chain, or cleaves from the middle of the molecular structure of the leaving group.

  As a result, in the irradiated region 925, the number of leaving groups in a complete state is reduced as compared with the non-irradiated region 940, and the refractive index is lowered to be lower than the first refractive index. At this time, the refractive index of the unirradiated region 940 is maintained at the first refractive index.

In this case, the irradiation dose of the actinic radiation 930 is preferably in the range of about 0.1~9J / cm ^2, more preferably about 0.2~5J / cm ^2, 0.2~4J / More preferably, it is about cm ² . Thereby, a promoter can be activated reliably.

[3C] The same step as the above step [3A] is performed.
Thereby, in the irradiation region 925, the catalyst precursor in the active latent state is activated (becomes active), and monomer reaction (polymerization reaction or cross-linking reaction) occurs.

  As the monomer reaction proceeds, the monomer concentration in the irradiation region 925 gradually decreases. As a result, there is a difference in monomer concentration between the irradiated region 925 and the unirradiated region 940, and the monomer diffuses from the unirradiated region 940 and collects in the irradiated region 925 in order to eliminate this.

  In addition, by this heat treatment, the leaving group detached (cut) from the polymer 915 is removed from, for example, the irradiation region 925, or rearranged or crosslinked in the polymer 915.

  As a result, in the irradiated region 925, the monomer and its reactant (polymer, cross-linked structure and branched structure) increase, and the structure derived from the monomer greatly affects the refractive index of the region. The refractive index is further lowered to the second refractive index due to a decrease in the leaving (cleaved) leaving group.

  On the other hand, in the unirradiated region 940, the amount of monomer decreases due to the diffusion of the monomer from the region to the irradiated region 925, so that the influence of the polymer 915 greatly appears on the refractive index of the region, and the first refraction The third refractive index is higher than the refractive index.

  In this way, a refractive index difference (second refractive index <third refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed.

[4C] A step similar to the step [4A] is performed.
[5C] A step similar to the step [5A] is performed.
[6C] The same step as the above step [6A] is performed.
[7C] The same step as the above step [7A] is performed.

The optical waveguide 9 is completed as described above.
In a preferred example of such an optical waveguide 9, the core layer 93 includes a norbornene-based polymer having a main chain and a leaving group that is branched from the main chain and at least a part of the molecular structure can be detached from the main chain. The core portion 94 and the clad portion 95 are different in the number of leaving groups bonded to the main chain, and the content of the norbornene monomer reactant having a different refractive index from that of the norbornene polymer. Are different in refractive index, and the clad layers 91 and 92 are mainly composed of a norbornene-based polymer whose refractive index is lower than that of the core portion 94 of the core layer 93.

  Since the norbornene-based polymer has high transparency, the optical waveguide 9 having such a configuration can provide high optical transmission performance.

  Further, with such a configuration, not only high adhesion between the core portion 94 and the clad portion 95 but also high adhesion between the core layer 93, the clad layer 91, and the clad layer 92 can be obtained. 9, even when deformation such as bending occurs, peeling between the core portion 94 and the clad portion 95 and delamination between the core layer 93 and the clad layers 91 and 92 hardly occur. It is also possible to prevent micro cracks from occurring. As a result, the optical transmission performance of the optical waveguide 9 is maintained.

  Further, since the norbornene-based polymer has high heat resistance and high hydrophobicity, the optical waveguide 9 having such a configuration has excellent durability.

  In addition, since the optical waveguide 9 can be imparted with high heat resistance and high hydrophobicity, the conductor layer can be reliably formed by adopting various methods as described above while preventing deterioration (deterioration) of its characteristics. can do. In particular, even when the conductor layer is formed so as to overlap the core portion 94 important for light transmission, the core portion 94 can be prevented from being deteriorated or deteriorated.

  Further, according to the manufacturing method as described above, the optical waveguide 9 having the core portion 94 having a desired shape and high dimensional accuracy can be obtained by a simple process and in a short time.

  In particular, according to the third manufacturing method, the refractive index difference between the core portion 94 and the cladding portion 95 can be set in multiple stages.

<Fourth manufacturing method>
Next, the 4th manufacturing method of the optical waveguide 9 is demonstrated.

  FIGS. 13A to 13E are cross-sectional views schematically showing a process example of the fourth manufacturing method of the optical waveguide.

  Hereinafter, although the 4th manufacturing method is explained, it explains centering on difference with the 1st-3rd manufacturing methods, and omits the explanation about the same matter.

  In the fourth manufacturing method, the same material as described in the first to third manufacturing methods can be used for the core layer forming material 900 and the cladding layer forming material.

  In the following description, the case where the materials described in the first manufacturing method are used as the core layer forming material will be described as a representative.

[1D] First, a clad layer forming material (first varnish) is applied onto the support substrate 1000 using the same method as described above to form the first layer 1110 (FIG. 13-A). reference).
As the support substrate 1000, a substrate similar to the support substrate 951 can be used.

  The average thickness of the first layer 1110 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 10 to 100 μm, and still more preferably about 15 to 65 μm.

  [2D] Next, a core layer forming material (second varnish) is applied onto the first layer 1110 using the same method as described above to form the second layer 1120 (FIG. 13-B).

  The core layer forming material may be applied after the first layer 1110 is almost completely dried, or may be applied before the first layer 1110 is dried.

  In the latter case, the first layer 1110 and the second layer 1120 are mixed with each other at the interface between them. In this case, in the obtained optical waveguide 9, the adhesion between the clad layer 91 and the core layer 93 can be improved.

  In this case, each of the first varnish and the second varnish is prepared so that the viscosity (normal temperature) is preferably about 100 to 10000 cP, more preferably about 150 to 5000 cP, and further preferably about 200 to 3500 cP. Thus, the first layer 1110 and the second layer 1120 can be prevented from being mixed more than necessary at the interface between them, and the thicknesses of the first layer 1110 and the second layer 1120 can be reduced. Nonuniformity can be prevented.

  The viscosity of the second varnish is preferably higher than that of the first varnish. Accordingly, it is possible to reliably prevent the first layer 1110 and the second layer 1120 from being mixed more than necessary at the interface between them.

  The average thickness of the second layer 1120 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 15 to 125 μm, and still more preferably about 25 to 100 μm.

  [3D] Next, a clad layer forming material (third varnish) is applied onto the second layer 1120 using the same method as described above to form the third layer 1130 (FIG. 13-C).

The third layer 1130 can be formed in the same manner as the second layer 1120.
The average thickness of the third layer 1130 is not particularly limited, but is preferably about 5 to 200 μm, more preferably about 10 to 100 μm, and still more preferably about 15 to 65 μm.
Thereby, the laminated body 2000 is obtained.

[4D] Next, the solvent in the laminate 2000 is removed (desolvent).
Examples of the method for removing the solvent include methods such as heating, leaving under atmospheric pressure or reduced pressure, and spraying (blowing) an inert gas, etc., but a method using heating is preferred. Thereby, it is possible to remove the solvent relatively easily and in a short time.

  The heating temperature is preferably about 25 to 60 ° C, and more preferably about 30 to 45 ° C.

  The heating time is preferably about 15 to 60 minutes, and more preferably about 15 to 30 minutes.

  [5D] Next, a mask (masking) 935 in which an opening (window) 9351 is formed is prepared, and the stacked body 2000 is irradiated with active radiation 930 through the mask 935 (see FIG. 13-D). .

  When the stacked body 2000 is irradiated with the active radiation 930 through the mask 935, the promoter (first substance: cocatalyst) present in the irradiation region 925 irradiated with the active radiation 930 of the second layer 1120 is: It reacts or decomposes by the action of actinic radiation 930 to liberate (generate) cations (protons or other cations) and weakly coordinating anions (WCA).

  These cations and weakly coordinating anions cause a change (decomposition) in the molecular structure of the catalyst precursor (second substance: procatalyst) present in the irradiation region 925, and this changes the active latent state (latent potential). Active state).

[6D] Next, heat treatment (first heat treatment) is performed on the stacked body 2000.
Thereby, in the irradiation region 925, the catalyst precursor in the active latent state is activated (becomes active), and monomer reaction (polymerization reaction or cross-linking reaction) occurs.

  As the monomer reaction proceeds, the monomer concentration in the irradiation region 925 gradually decreases. As a result, there is a difference in monomer concentration between the irradiated region 925 and the unirradiated region 940, and the monomer diffuses from the unirradiated region 940 and collects in the irradiated region 925 in order to eliminate this.

  As a result, in the irradiated region 925, the monomer and its reaction product (polymer, cross-linked structure or branched structure) increase, and the structure derived from the monomer greatly affects the refractive index of the region, so that the first refraction The second refractive index lower than the refractive index.

  On the other hand, in the unirradiated region 940, the amount of monomer decreases due to the diffusion of the monomer from the region to the irradiated region 925, so that the influence of the polymer 915 greatly appears on the refractive index of the region, and the first refraction The third refractive index is higher than the refractive index.

  In this way, a refractive index difference (second refractive index <third refractive index) occurs between the irradiated region 925 and the non-irradiated region 940, and the core portion 94 (non-irradiated region 940) and the cladding portion 95. (Irradiation region 925) is formed (see FIG. 13-E).

[7D] Next, the stacked body 2000 is subjected to a second heat treatment.
As a result, the catalyst precursor remaining in the unirradiated region 940 and / or the irradiated region 925 is activated (activated) directly or with activation of the cocatalyst, thereby causing the regions 925 and 940 to be activated. The remaining monomer is reacted.

  In this way, by reacting the monomers remaining in the regions 925 and 940, the core portion 94 and the clad portion 95 obtained can be stabilized.

[8D] Next, the stacked body 2000 is subjected to a third heat treatment.
Thereby, the internal stress generated in the obtained core layer 93 can be reduced, and the core portion 94 and the cladding portion 95 can be further stabilized.
The optical waveguide 9 is obtained through the above steps.

  In such a method, the core portion 94 can be visually confirmed in the stacked body 2000 after the first heat treatment.

  Further, as the first varnish and the third varnish, the same composition as that of the second varnish, that is, one containing a polymer 915, a monomer, a promoter and a catalyst precursor may be used. Accordingly, the monomer reaction causes the interface between the first layer 1110 and the third layer 1130 and the second layer 1120, and / or beyond the interface, in the first layer 1110 and the third layer 1130. And the peeling between the clad layers 91 and 92 and the core layer 93 can be prevented more reliably.

  Further, in this case, for example, I: As the polymer 915 of the first layer 1110 and the third layer 1130, one having a refractive index (RI) relatively lower than the refractive index of the polymer 915 of the second layer 1120 is selected. II: The same monomer as the second layer 1120 is used as the monomer of the first layer 1110 and the third layer 1130, but the catalyst precursor in the first layer 1110 and the third layer 1130 and The monomer ratio may be adjusted to be lower than that of the second layer 1120.

  Accordingly, even when the active radiation 930 is irradiated, it is possible to prevent the formation of a region having a refractive index higher than that of the core portion 94 of the core layer 93 in the cladding layers 91 and 92.

  When a material containing a polymer 915 having a leaving group is used as the core layer forming material (second varnish), the cladding layer forming material (first varnish, third varnish) A polymer prepared using a polymer 915 having no releasing group is used, or a polymer 915 having a releasing group is used, but a polymer containing no releasing agent may be used.

  Thereby, in the first layer 1110 and the third layer 1130, it is possible to prevent the leaving group from leaving (decomposing) from the polymer 915.

  In this case, a promoter that is not activated when the core layer 93 is formed may be selected. For example, a cocatalyst that does not absorb actinic radiation suitable for activating the cocatalyst contained in the second varnish or is activated by the action of heat in place of the actinic radiation may be selected.

  Examples of such a co-catalyst include a non-absorbing photobase generator (PBG) and a thermal base generator (TBG).

  In the present invention, it goes without saying that the basic structure, layer structure, shape, number, arrangement, etc. of the optical waveguide structure are not limited to those shown in the drawings.

  In each of the above embodiments, the light emitting element 10 has been described as a representative example of the element. However, a configuration in which the light receiving element 11 is mounted instead of the light emitting element 10 may be used. In this case, the optical waveguide 9 can be configured to guide the light guide formed by the core portion 94 to the light receiving portion 111 of the light receiving element 11. Of course, at least one set of both the light emitting element and the light receiving element may be mounted.

  The present invention has been described based on the illustrated embodiments. However, the present invention is not limited to these embodiments, 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.

DESCRIPTION OF SYMBOLS 1 Optical waveguide structure 2, 2 'board | substrate 21 Translucent part 22 Through-hole 23 Vertical optical waveguide 24 Core part 25 Clad part 26 Lens part 3 Adhesive layer 4, 41 Underfill material 51, 52, 54, 55 Conductor layer 6, 61 Sealing material 7 Solder 8 Through hole (through hole)
81, 82 Conductor post (conductive material)
9, 9 'Optical waveguide 91 Clad layer 92 Clad layer 93 Core layer 94 Core part 95 Clad part 96 Optical path conversion part 961 Reflecting surface 96a, 96b, 96c, 96d, 96e, 96f Optical path conversion part 961a, 961b, 961c, 961d, 961e, 961f Reflecting surface 10 Light emitting element 101 Light emitting part 103 Terminal 105 Terminal 11 Light receiving element 111 Light receiving part 113 Terminal 115 Terminal 12 Electric element (semiconductor element)
123 terminal 125 terminal 127 terminal 129 terminal 13 chip carrier 900 core layer forming material 910 layer 915 polymer 920 additive 925 irradiated region 930 actinic radiation 935 mask 9351 opening 940 unirradiated region 951, 952 supporting substrate 1000 supporting substrate 1110 first Layer 1120 Second layer 1130 Third layer 2000 Laminate

Claims (10)

A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core portion and a cladding portion having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having a refractive index different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for manufacturing an optical waveguide, wherein the first clad layer forming layer and the second clad layer forming layer each contain the monomer at a lower ratio than the core layer forming layer . A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core portion and a cladding portion having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having a refractive index different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for manufacturing an optical waveguide, wherein the first cladding layer forming layer and the second cladding layer forming layer each contain the substance . A method of manufacturing an optical waveguide in which a first cladding layer, a core layer having a core portion and a cladding portion having different refractive indexes , and a second cladding layer are laminated in this order ,
A first cladding layer forming layer for forming the first cladding layer is formed on the substrate, and then a main chain and at least one molecular structure branched from the main chain is formed on the first cladding layer forming layer. a polymer part having a leaving group which can be detached from the main chain, coated fabric a photosensitive resin composition containing a monomer having a refractive index different from that of the polymer, the substance activating upon exposure to actinic radiation, the Forming a core layer forming layer, and then forming a second clad layer forming layer for forming the second clad layer on the core layer forming layer to obtain a laminate;
By selectively irradiating a part of the laminate with the actinic radiation, the substance in the irradiation region of the core layer forming layer is activated and the monomer in the irradiation region is reacted. is, together to rise to movement of said monomers into the irradiated region from the non-irradiated region with it, by disengaging the cleavable groups in the irradiated area, between the irradiation region and the non-illuminated region Producing a difference in refractive index to obtain the core layer, and obtaining the first cladding layer and the second cladding layer , and
The method for producing an optical waveguide, wherein the first cladding layer forming layer and the second cladding layer forming layer each contain the polymer not having the leaving group . The method for producing an optical waveguide according to claim 1, wherein the polymer is mainly a cyclic olefin-based polymer. The method for producing an optical waveguide according to claim 1, wherein the monomer is compatible with the polymer and can cause a polymerization reaction or a crosslinking reaction in the polymer. After irradiation with the active radiation to the core layer forming layer, a method of manufacturing an optical waveguide according to any one of claims 1 to 5 subjected to a heat treatment to the core layer forming layer. The leaving group is cationic, a method of manufacturing an optical waveguide according to either anion or claims 1 in which leaves by the action of free radicals 6. The substance, a method of manufacturing an optical waveguide according to any one of claims 1 to 7 including an acid generator. The method for producing an optical waveguide according to claim 8 , wherein the leaving group has at least one of an —O— structure, an —Si—aryl structure, and an —O—Si— structure. The optical waveguide is formed with an optical path conversion part that bends the optical path of the core part,
The optical path changing part is composed of one inclined surface in a recess formed across at least two layers of the core layer and the second cladding layer,
After forming the core layer, the optical waveguide manufacturing method according to any one of claims 1 to 9 to form the recess by removing a portion of the at least two layers of the core layer and the second clad layer .

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