JP5685926B2 - Photoelectric composite substrate and manufacturing method thereof - Google Patents

Description

  The present invention relates to a photoelectric composite substrate and a method for manufacturing the same.

  With the increase in information capacity, development of an optical interconnection technology that uses optical signals not only for communication fields such as trunk lines and access systems but also for information processing in routers and servers is underway. Specifically, in order to use light for short-distance signal transmission between boards in a router or a server device or in a board, an opto-electric composite board in which an optical transmission path is combined with an electric wiring board has been developed. As the optical transmission line, it is desirable to use an optical waveguide that has a higher degree of freedom of wiring and can be densified than an optical fiber, and among them, an optical waveguide that uses a polymer material that is excellent in processability and economy. Promising.

In the manufacture of this optoelectric composite substrate, it is necessary that the relationship between the position of the optical transmission path and the mounting position of the optical element is highly accurate. As such a technique, for example, Patent Document 1 discloses: A technique for forming a mounting groove pattern of an optical element and an electrode pattern or alignment marker that serves as a mark when mounting the optical element with the same photomask is disclosed. However, this method controls the positional relationship between the optical fiber and the optical element, and is not applicable to alignment between the position of the optical waveguide composed of the core and the clad and the mounting position of the optical element.
Patent Document 2 discloses a method of forming a core portion of an optical waveguide and a marker used as a reference point for positioning an optical element using the same mask. However, in this method, the alignment marker formed on the substrate may be displaced due to thermal history or the like due to various subsequent processes.

JP-A-10-170773 Japanese Patent Laid-Open No. 11-190811

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an optoelectric composite substrate with little positional deviation between an optical waveguide and a wiring pattern, and a method for manufacturing the same.

As a result of extensive studies, the present inventors have provided an optical signal transmission core pattern on the lower cladding layer and a resist core pattern on the enlarged wiring pattern, and are covered with the resist core pattern of the enlarged wiring pattern. The present inventors have found that the above problems can be solved by a photoelectric composite substrate obtained by removing a portion that is not present, and have completed the present invention.
That is, the present invention
1. A photoelectric composite substrate having a patterned lower clad layer, optical signal transmission core pattern, resist core pattern, wiring pattern with the resist core pattern, and upper clad layer on a base material, the wiring A photoelectric composite substrate, wherein the pattern is provided in the pattern-shaped opening of the lower clad layer, and is sandwiched between the base material and the resist core pattern in the stacking direction,
2. 2. The photoelectric composite substrate according to 1 above, wherein the resist core pattern and the wiring pattern are exposed to the outside,
3. The photoelectric composite substrate according to 1 or 2 above, wherein the resist core pattern is made of the same material as the optical signal transmission core pattern,
4). The photoelectric composite substrate according to 1 or 2, wherein the wiring pattern is in contact with the resist core pattern,
5. (A) a step of forming an enlarged wiring pattern on the substrate, (B) a step of forming a lower clad layer patterned in the opening of the enlarged wiring pattern, and (C) an optical signal transmission on the lower clad layer Forming a core pattern, laminating a narrower resist core pattern on the enlarged wiring pattern, and (D) forming an upper clad layer so as to cover the optical signal transmission core pattern; E) The method for producing an optoelectric composite substrate according to any one of the above 1 to 4, further comprising a step of removing a portion of the enlarged wiring pattern where the resist core pattern is not laminated to form a wiring pattern.
6). Step (A) to Step (D), (D ′) The photoelectric composite according to 5 above, wherein the upper cladding layer is patterned to expose the resist core pattern and the enlarged wiring pattern, and the step (E) is performed in this order. Substrate manufacturing method,
7). The method for producing an optoelectric composite substrate according to 5 above, wherein the step (A) to the step (C), the step (E), and the step (D) are performed in this order,
8). The method for producing a photoelectric composite substrate according to any one of 5 to 7 above, wherein the step (E) is performed by etching treatment,
9. (A) a step of forming an enlarged wiring pattern on the substrate, (B ′) a step of forming a patterned lower cladding layer on the enlarged wiring pattern, and (C) an optical signal transmission core on the lower cladding layer. Forming a pattern and laminating a narrower resist core pattern on the enlarged wiring pattern; (D) forming an upper cladding layer so as to cover the optical signal transmission core pattern; and (E) enlargement. The method for producing a photoelectric composite substrate according to any one of the above 1 to 4, further comprising a step of removing a portion of the wiring pattern where the resist core pattern is not laminated to form a wiring pattern,
10. Step (A), Step (B ′), Step (C), Step (D), (D ′) Patterning the upper cladding layer to expose the resist core pattern and the enlarged wiring pattern, Step (E) The method for producing a photoelectric composite substrate according to 9 above, which is performed in this order
11. 10. The method for producing an optoelectric composite substrate according to 9 above, wherein the step (A), the step (B ′), the step (C), the step (E), and the step (D) are performed in this order; The method for producing a photoelectric composite substrate according to any one of 9 to 11, wherein the step (E) is performed by an etching process,
Is to provide.

  According to the optoelectric composite substrate of the present invention, it is possible to obtain an optoelectric composite substrate with little positional deviation between the optical waveguide and the wiring pattern.

It is sectional drawing which shows the one aspect | mode of the photoelectric composite board | substrate of this invention. It is sectional drawing which shows the one aspect | mode of the photoelectric composite board | substrate of this invention. It is sectional drawing which shows each process of 1 aspect of the 1st manufacturing method of the photoelectric composite board | substrate of this invention. It is sectional drawing which shows each process of 1 aspect of the 1st manufacturing method of the photoelectric composite board | substrate of this invention. It is sectional drawing which shows each process of 1 aspect of the 2nd manufacturing method of the photoelectric composite board | substrate of this invention. It is sectional drawing which shows each process of 1 aspect of the 2nd manufacturing method of the photoelectric composite board | substrate of this invention.

As shown in FIGS. 1 and 2, the optoelectric composite substrate of the present invention has a patterned lower clad layer 2, an optical signal transmission core pattern 3, a resist core pattern 4, and a resist core on a substrate 1. An optoelectric composite substrate having a wiring pattern 5 and an upper clad layer 6 with the pattern, the wiring pattern 5 being provided in a pattern-shaped opening of the lower clad layer 2, and the substrate 1 in the stacking direction And the resist core pattern 4.
Here, the wiring pattern 5 is provided in the pattern-shaped opening of the lower cladding layer 2. At least a part of the wiring pattern 5 is formed in the pattern-shaped opening of the lower cladding layer 2. Indicates the state.
The wiring pattern 5 being sandwiched between the base material 1 and the resist core pattern 4 in the stacking direction means a state in which the base material 1, the wiring pattern 5 and the resist core pattern 4 are stacked in this order. .
In the photoelectric composite substrate of the present invention, an enlarged wiring pattern 5a described later may partially remain between the base material 1 and the lower cladding layer 2.

Moreover, as shown in FIG.3 and FIG.4, the manufacturing method of the 1st photoelectric composite board | substrate of this invention is a process of forming an enlarged wiring pattern on a base material, and (B) an enlarged wiring pattern. Forming a lower clad layer in the opening; and (C) forming an optical signal transmission core pattern on the lower clad layer and laminating a narrower resist core pattern on the enlarged wiring pattern; , (D) forming an upper cladding layer so as to cover the optical signal transmission core pattern, and (E) forming a wiring pattern by removing a portion of the enlarged wiring pattern where the resist core pattern is not laminated. Process.
When the order of performing the steps (A) to (E) is the order of the steps (A) to (D), the step (D ′) to be described later, and the step (E), the optical signal in the step (D). Since the transmission core pattern is covered with the upper clad layer, it is preferable in that the core pattern can be prevented from being colored in the etching step of the step (E). On the other hand, when it carries out in order of a process (A)-a process (C), a process (E), and a process (D), it is preferable at the point by which a manufacturing process is simplified.
Furthermore, as shown in FIGS. 5 and 6, the second method for manufacturing a photoelectric composite substrate of the present invention includes (A) a step of forming an enlarged wiring pattern on a substrate, and (B ′) an enlarged wiring pattern. Forming a patterned lower clad layer on the upper surface; and (C) forming an optical signal transmission core pattern on the lower clad layer and laminating a narrower resist core pattern on the enlarged wiring pattern; , (D) forming an upper cladding layer so as to cover the optical signal transmission core pattern, and (E) forming a wiring pattern by removing a portion of the enlarged wiring pattern where the resist core pattern is not laminated. Process.
The order of carrying out the steps (A) to (E) is as follows: step (A), step (B ′), step (C), step (D), step (D ′) to be described later, step (E). This is preferable in that the core pattern for optical signal transmission is covered with the upper clad layer in the step (D), so that the core pattern can be prevented from being colored in the etching step of the step (E). On the other hand, it is preferable to perform the steps (A), (B ′), (C), (E), and (D) in this order in that the manufacturing process is simplified.

<Process (A)>
In the step (A), the enlarged wiring pattern 5 a is formed on the base material 1.
(Base material)
The substrate 1 is not particularly limited as long as it has sufficient strength to withstand the lamination of each layer in the steps (A) to (E). For example, a glass epoxy resin substrate, a ceramic substrate, a glass substrate, silicon Examples include a substrate, a plastic substrate, a metal substrate, a substrate with a resin layer, a substrate with a metal layer, a plastic film, a plastic film with a resin layer, and a plastic film with a metal layer.
As the substrate 1, a base material having flexibility and toughness, for example, a carrier film of a clad forming resin film and a core layer forming resin film, which will be described later, may be used as the substrate.
(Expanded wiring pattern)

As the enlarged wiring pattern 5a, in the step (E), since it is necessary to form the wiring pattern 5 using the resist core pattern as a resist, a pattern wider than the wiring pattern 5 is provided. The material and the patterning method are not particularly limited, and examples thereof include a copper layer formed with a circuit by an ordinary method such as etching.
In the second manufacturing method of the present invention, as shown in FIGS. 5 and 6, the copper layer may be left on the entire surface.

<Process (B)>
In the step (B) in the first manufacturing method of the present invention, the patterned lower cladding layer 2 is formed in the opening of the enlarged wiring pattern 5a.
(Lower cladding layer)
The method of forming the lower clad layer 2 in the opening of the enlarged wiring pattern 5a is not particularly limited, and may be a known method. For example, a clad layer forming resin is applied on the substrate 1 and the enlarged wiring pattern 5a. Alternatively, a clad layer-forming resin film is laminated to form a clad layer on the entire surface, and then patterned. In the case of application, the method is not limited, and the clad layer forming resin may be applied by a conventional method such as spin coating. Moreover, the resin film for clad layer formation used for a lamination can be easily manufactured, for example by melt | dissolving the said resin in a solvent, apply | coating to a carrier film, and removing a solvent.

  The clad layer forming resin used in the present invention is not particularly limited as long as it is a resin composition that has a lower refractive index than the optical signal transmission core pattern 3 and is cured by light or heat, and is not limited. Can be suitably used. More preferably, the clad layer forming resin is preferably composed of a resin composition containing (A) a base polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. The resin composition used for the clad forming resin may be the same or different in the components contained in the resin composition in the lower clad layer 2 and the upper clad layer 6. The rates may be the same or different.

  The (A) base polymer used here is for forming a clad and ensuring the strength of the clad, and is not particularly limited as long as the object can be achieved. Phenoxy resin, epoxy resin, (meta ) Acrylic resin, polycarbonate resin, polyarylate resin, polyether amide, polyether imide, polyether sulfone, etc., or derivatives thereof. These base polymers may be used alone or in combination of two or more. Of the base polymers exemplified above, from the viewpoint of high heat resistance, the main chain preferably has an aromatic skeleton, and particularly preferably a phenoxy resin. From the viewpoint of three-dimensional crosslinking and improving heat resistance, an epoxy resin, particularly an epoxy resin that is solid at room temperature is preferable. Further, compatibility with the photopolymerizable compound (B) described in detail later is important for ensuring the transparency of the resin for forming the cladding layer. From this point, the phenoxy resin and the (meth) acrylic resin are used. Is preferred. Here, (meth) acrylic resin means acrylic resin and methacrylic resin.

  Among phenoxy resins, those containing bisphenol A, bisphenol A type epoxy compounds or derivatives thereof, and bisphenol F, bisphenol F type epoxy compounds or derivatives thereof as a constituent unit of the copolymer component are heat resistant, adhesive and soluble. It is preferable because of its excellent properties. Preferred examples of the bisphenol A or bisphenol A type epoxy compound include tetrabromobisphenol A and tetrabromobisphenol A type epoxy compounds. Moreover, as a derivative of bisphenol F or a bisphenol F-type epoxy compound, tetrabromobisphenol F, a tetrabromobisphenol F-type epoxy compound, etc. are mentioned suitably. Specific examples of the bisphenol A / bisphenol F copolymer type phenoxy resin include “Phenotote YP-70” (trade name) manufactured by Toto Kasei Co., Ltd.

  Examples of the epoxy resin that is solid at room temperature include, for example, “Epototo YD-7020, Epototo YD-7019, Epototo YD-7007” (all trade names) manufactured by Toto Chemical Co., Ltd., and “Epicoat 1010” manufactured by Japan Epoxy Resins Co., Ltd. Bisphenol A type epoxy resin such as “Epicoat 1009, Epicoat 1008” (both trade names).

Next, (B) the photopolymerizable compound is not particularly limited as long as it is polymerized by irradiation with light such as ultraviolet rays, and the compound having an ethylenically unsaturated group in the molecule or two or more in the molecule. Examples thereof include compounds having an epoxy group.
Examples of the compound having an ethylenically unsaturated group in the molecule include (meth) acrylate, vinylidene halide, vinyl ether, vinyl pyridine, vinyl phenol, etc., among these, from the viewpoint of transparency and heat resistance, (Meth) acrylate is preferred.
As the (meth) acrylate, any of monofunctional, bifunctional, trifunctional or higher polyfunctional ones can be used. Here, (meth) acrylate means acrylate and methacrylate.
Examples of the compound having two or more epoxy groups in the molecule include bifunctional or polyfunctional aromatic glycidyl ethers such as bisphenol A type epoxy resins, bifunctional or polyfunctional aliphatic glycidyl ethers such as polyethylene glycol type epoxy resins, and water. Bifunctional alicyclic glycidyl ether such as bisphenol A type epoxy resin, bifunctional aromatic glycidyl ester such as diglycidyl phthalate, bifunctional alicyclic glycidyl ester such as tetrahydrophthalic acid diglycidyl ester, N, N- Bifunctional or polyfunctional aromatic glycidylamine such as diglycidylaniline, bifunctional alicyclic epoxy resin such as alicyclic diepoxycarboxylate, bifunctional heterocyclic epoxy resin, polyfunctional heterocyclic epoxy resin, bifunctional Or polyfunctional silicon-containing epoxy resin It is. These (B) photopolymerizable compounds can be used alone or in combination of two or more.

  Next, the photopolymerization initiator of component (C) is not particularly limited. For example, as an initiator when an epoxy compound is used as component (B), aryldiazonium salt, diaryliodonium salt, triarylsulfonium salt, triallyl Examples include selenonium salts, dialkylphenazylsulfonium salts, dialkyl-4-hydroxyphenylsulfonium salts, and sulfonate esters. When a luminescent photopolymerization initiator is used, a luminescent cladding layer can be obtained.

Moreover, as an initiator in the case of using a compound having an ethylenically unsaturated group in the molecule as the component (B), aromatic ketones such as benzophenone, quinones such as 2-ethylanthraquinone, benzoin ethers such as benzoin methyl ether Compounds, benzoin compounds such as benzoin, benzyl derivatives such as benzyldimethyl ketal, 2,4,5-triarylimidazole dimers such as 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- Benzimidazoles such as mercaptobenzimidazole, phosphine oxides such as bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, acridine derivatives such as 9-phenylacridine, N-phenylglycine, N-phenylglycine derivatives , Coumarin compound And the like. Moreover, you may combine a thioxanthone type compound and a tertiary amine compound like the combination of diethyl thioxanthone and dimethylaminobenzoic acid. Of the above compounds, aromatic ketones and phosphine oxides are preferable from the viewpoint of improving the transparency of the cladding layer.
These (C) photopolymerization initiators can be used alone or in combination of two or more.

(A) It is preferable that the compounding quantity of a base polymer shall be 5-80 mass% with respect to the total amount of (A) component and (B) component. Moreover, it is preferable that the compounding quantity of (B) photopolymerizable compound shall be 95-20 mass% with respect to the total amount of (A) and (B) component.
As a blending amount of the component (A) and the component (B), when the component (A) is 5% by mass or more and the component (B) is 95% by mass or less, the resin composition is easily formed into a film. Can do. On the other hand, when the component (A) is 80% by mass or less and the component (B) is 20% by mass or more, the (A) base polymer can be easily entangled and cured, and the pattern formability is improved. And the photocuring reaction proceeds sufficiently. From the above viewpoint, the blending amount of the component (A) and the component (B) is more preferably 10 to 85% by mass of the component (A) and 90 to 15% by mass of the component (B), and 20 to 70 of the component (A). More preferably, the content is 80% by mass and the component (B) is 80 to 30% by mass.
(C) It is preferable that the compounding quantity of a photoinitiator shall be 0.1-10 mass parts with respect to 100 mass parts of total amounts of (A) component and (B) component. When the blending amount is 0.1 parts by mass or more, the photosensitivity is sufficient, while when it is 10 parts by mass or less, the absorption in the surface layer of the photosensitive resin composition does not increase during exposure, and the internal Is sufficiently cured. Furthermore, when used as a core layer to be described later, it is preferable that the light propagation loss does not increase due to the light absorption effect of the polymerization initiator itself. From the above viewpoint, the blending amount of the (C) photopolymerization initiator is more preferably 0.2 to 5 parts by mass.
In addition, if necessary, in the cladding layer forming resin, an antioxidant, an anti-yellowing agent, an ultraviolet absorber, a visible light absorber, a colorant, a plasticizer, a stabilizer, a filler, etc. You may add what is called an additive in the ratio which does not have a bad influence on the effect of this invention. Further, if the additive has luminescent properties, a luminescent cladding layer can also be obtained.

The carrier film used in the production process of the resin film for forming the clad layer is not particularly limited in terms of material, but for example, an FR-4 substrate, a polyimide substrate, a semiconductor substrate, a silicon substrate, a glass substrate, or the like is used. It may be a flexible material with flexibility or a non-flexible hard material.
Further, by using a flexible material for the carrier film, the photoelectric composite substrate 10 can be provided with flexibility. The material of the material having flexibility is not particularly limited, but from the viewpoint of having flexibility and toughness, polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, polyamide, polycarbonate, Preferable examples include polyphenylene ether, polyether sulfide, polyarylate, liquid crystal polymer, polysulfone, polyether sulfone, polyether ether ketone, polyether imide, polyamide imide, and polyimide.
The thickness of the carrier film may be appropriately changed depending on the intended flexibility, but is preferably 5 to 250 μm. If it is 5 μm or more, there is an advantage that toughness is easily obtained, and if it is 250 μm or less, sufficient flexibility can be obtained.
The solvent used here is not particularly limited as long as it can dissolve the resin composition. For example, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylacetamide, propylene glycol monomethyl ether, A solvent such as propylene glycol monomethyl ether acetate, cyclohexanone, N-methyl-2-pyrrolidone, or a mixed solvent thereof can be used. The solid content concentration in the resin solution is preferably about 30 to 80% by mass.

  Regarding the thickness of the cladding layer, the thickness after drying is preferably in the range of 5 to 500 μm. When the thickness is 5 μm or more, a thickness necessary for light confinement can be secured, and when the thickness is 500 μm or less, the film thickness can be easily controlled uniformly. From the above viewpoint, the thickness of the cladding layer is more preferably in the range of 10 to 100 μm.

  The thickness of the clad layer may be the same or different in the lower clad layer 2 and the upper clad layer 6, but the thickness of the upper clad layer 6 is embedded in order to embed the optical signal transmission core pattern 3. Is preferably thicker than the thickness of the optical signal transmission core pattern 3.

(Patterning method)
The patterning method of the lower cladding layer 2 is usually performed by pattern-exposing the lower cladding layer 2 and then developing and removing the uncured portion.
The exposure method is not particularly limited, and may be either a negative type in which an exposed portion remains as a pattern or a positive type in which an unexposed portion remains as a pattern, and may be determined according to the properties of the resin composition for forming a cladding layer to be used. .

<Process (B ')>
In the step (B ′) in the second manufacturing method of the present invention, the patterned lower cladding layer 2 is formed on the enlarged wiring pattern 5a.
The formation method, patterning method, and the like of the lower clad layer 2 are the same as in the above-described step (B).

<Process (C)>
In the step (C), the optical signal transmission core pattern 3 is formed on the lower clad layer 2, and the narrower resist core pattern 4 is laminated on the enlarged wiring pattern 5a.
Here, since the optical signal transmission core pattern 3 and the resist core pattern 4 are formed using the same photomask, the photomask is different from the conventional one formed using different photomasks. There is no misalignment due to the alignment. In addition, the optical signal transmission core pattern 3 and the resist core pattern 4 are usually formed using the same material.
The formation method of the optical signal transmission core pattern 3 and the resist core pattern 4 is not particularly limited, and may be a known method. For example, the refractive index of the lower clad layer 2 and the enlarged wiring pattern 5 a is higher than that of the lower clad layer 2. After forming a high core layer, it can be formed in the same manner as the patterning method described above.
The lower clad layer 2 in contact with the optical signal transmission core pattern 3 is flat from the viewpoint of adhesion to the optical signal transmission core pattern 3 and has no step on the surface on the optical signal transmission core pattern 3 lamination side. preferable. Moreover, the surface flatness of the lower clad layer 2 can be ensured by using the clad forming resin film.
The resist core pattern 4 only needs to have at least a portion having the same shape as the wiring pattern 5, and may further have a portion capable of forming a position recognition marker (not shown). . The position recognition marker may be circular or ring-shaped, and an opening is formed by the resist core pattern 4, and the enlarged wiring pattern 5 a is removed from the opening. The wiring pattern 5a may be divided at the linear opening to form two wiring patterns.
As described above, in the photoelectric composite substrate of the present invention, the wiring pattern 5 is sandwiched between the base material 1 and the resist core pattern 4 in the stacking direction at least in the pattern-shaped opening of the lower cladding layer 2. It ’s fine.

The method for forming the core layer laminated on the lower clad layer 2 and the enlarged wiring pattern 5a is not particularly limited, and may be formed by, for example, applying a core layer forming resin or laminating a core layer forming resin film.
As the resin for forming the core layer, a resin composition that is designed so that the core layer has a higher refractive index than that of the clad layer and can form the core layer with actinic rays can be used, and depending on the emission wavelength from the lower clad A photosensitive resin composition to be cured or a core layer forming resin containing a photopolymerization initiator that initiates polymerization by the emission wavelength from the lower clad is suitable. Specifically, it is preferable to use the same resin composition as that used in the clad layer forming resin.
In the case of application, the method is not limited, and the resin composition may be applied by a conventional method.

Hereinafter, the resin film for core formation used for lamination will be described in detail.
The resin film for forming a core layer can be easily produced by dissolving the resin composition in a solvent, applying the resin composition on a carrier film, and removing the solvent. The solvent used here is not particularly limited as long as it can dissolve the resin composition. For example, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, N, N-dimethyl A solvent such as acetamide, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, N-methyl-2-pyrrolidone, or a mixed solvent thereof can be used. It is preferable that the solid content concentration in the resin solution is usually 30 to 80% by mass.

  The thickness of the resin film for forming the core layer is not particularly limited, and the thickness of the core layer after drying is usually adjusted to be 10 to 100 μm. If the thickness of the film is 10 μm or more, there is an advantage that the alignment tolerance can be increased in the coupling with the light emitting / receiving element or the optical fiber after the optical waveguide is formed. In coupling with an element or an optical fiber, there is an advantage that coupling efficiency is improved. From the above viewpoint, the thickness of the film is preferably in the range of 30 to 70 μm.

The carrier film used in the production process of the core layer forming resin is a carrier film that supports the core layer forming resin, and the material thereof is not particularly limited, but the film material described above in the item of (carrier film) is preferable. It is mentioned in. Moreover, polyesters, such as a polyethylene terephthalate, a polypropylene, polyethylene, etc. are mentioned suitably from the viewpoint that it is easy to peel resin for core layer formation, and has heat resistance and solvent resistance.
The thickness of the carrier film is preferably 5 to 50 μm. When it is 5 μm or more, there is an advantage that the strength as a carrier film is easily obtained, and when it is 50 μm or less, there is an advantage that a gap with the mask at the time of pattern formation becomes small and a finer pattern can be formed. From the above viewpoint, the thickness of the carrier film is more preferably in the range of 10 to 40 μm, and particularly preferably 15 to 30 μm.

  In the manufacturing method of the present invention, a photoelectric composite substrate having a multilayer structure may be manufactured by laminating a plurality of core layers and cladding layers.

<Process (D)>
In the step (D), the upper clad layer 6 is formed so as to cover the optical signal transmission core pattern 3.
The method for forming the upper cladding layer 6 is not particularly limited, and for example, it may be formed by the same method as that for the lower cladding layer 2 before patterning.

<Process (D ')>
The step (D ′) is performed as necessary, and the upper cladding layer 6 is patterned to expose the resist core pattern 4 and the enlarged wiring pattern 5a.
The patterning method of the upper cladding layer 6 is not particularly limited, and can be performed, for example, in the same manner as the lower cladding layer 2.

<Process (E)>
In the step (E), a portion of the enlarged wiring pattern 5a where the resist core pattern 4 is not laminated is removed to form the wiring pattern 5.
Etching is preferably used as such a removal method. By removing the portion where the resist core pattern 4 is not laminated, the wiring pattern 5 remains, and various components can be mounted thereon.
As described above, since the optical signal transmission core pattern 3 and the resist core pattern 4 are formed by using the same photomask, there is no positional shift due to the alignment of the photomask. 5 also has a good alignment with the optical signal transmitting core pattern 3 because the portion masked by the resist core pattern 4 remains in the step (E).

EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
Example 1
[Preparation of resin film for forming clad layer]
(A) As a base polymer, 48 parts by mass of a phenoxy resin (trade name: Phenototo YP-70, manufactured by Toto Kasei Co., Ltd.), (b) As a photopolymerizable compound, an alicyclic diepoxycarboxylate (trade name: KRM) -2110, molecular weight: 252, manufactured by Asahi Denka Kogyo Co., Ltd.) 50 parts by mass, (c) As a photopolymerization initiator, triphenylsulfonium hexafluoroantimonate salt (trade name: SP-170, manufactured by Asahi Denka Kogyo Co., Ltd.) 2 parts by mass, 40 parts by mass of propylene glycol monomethyl ether acetate as an organic solvent are weighed in a wide-mouthed plastic bottle, and stirred for 6 hours under the conditions of a temperature of 25 ° C. and a rotation speed of 400 rpm using a mechanical stirrer, shaft and propeller. A clad layer forming resin varnish A was prepared. After that, using a polyflon filter (trade name: PF020, manufactured by Advantech Toyo Co., Ltd.) with a pore diameter of 2 μm, the mixture is filtered under pressure at a temperature of 25 ° C. and a pressure of 0.4 MPa, and further the degree of vacuum using a vacuum pump and a bell jar Degassed under reduced pressure for 15 minutes under the condition of 50 mmHg.
The coating varnish A for clad layer formation obtained above was applied to a corona-treated surface of a polyamide film (trade name “Mictron”, thickness 12 μm, manufactured by Toray Industries, Inc.) (Multicoater TM-MC, Inc. The resin film for clad layer formation was obtained by carrying out solvent drying at 80 ° C. for 10 minutes and then at 100 ° C. for 10 minutes. At this time, the thickness of the resin layer can be arbitrarily adjusted by adjusting the gap of the coating machine, and here, the thickness after curing was adjusted to be 70 μm. This obtained the resin film for upper clad layer 6 formation.
Coating the resin varnish A for forming a clad layer obtained above on a release polyethylene terephthalate (hereinafter referred to as “PET”) film (trade name: Purex A31, Teijin DuPont Films, Inc., thickness: 25 μm) Coating was performed using a machine (Multicoater TM-MC, manufactured by Hirano Techseed Co., Ltd.), and the solvent was dried at 80 ° C. for 10 minutes and then at 100 ° C. for 10 minutes to obtain a resin film for forming the lower cladding layer 2. At this time, the thickness of the resin layer can be arbitrarily adjusted by adjusting the gap of the coating machine. Here, the thickness after curing was adjusted to 15 μm. This obtained the resin film for lower clad layer 2 formation.

[Preparation of resin film for core layer formation]
(A) As a base polymer, 26 parts by mass of phenoxy resin (trade name: Phenototo YP-70, manufactured by Toto Kasei Co., Ltd.), (b) 9,9-bis [4- (2-acryloyl) as a photopolymerizable compound Oxyethoxy) phenyl] fluorene (trade name: A-BPEF, Shin-Nakamura Chemical Co., Ltd.) 36 parts by mass, and bisphenol A type epoxy acrylate (trade name: EA-1020, Shin-Nakamura Chemical Co., Ltd.) 36 mass Parts, (c) 1 part by weight of bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (trade name: Irgacure 819, manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator, and 1- [4 -(2-Hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one (trade name: yl Cure 2959, manufactured by Ciba Specialty Chemicals Co., Ltd.) A resin varnish B for forming a core layer was prepared by the same method and conditions as described above except that 1 part by mass and 40 parts by mass of propylene glycol monomethyl ether acetate as an organic solvent were used. . Thereafter, pressure filtration and degassing under reduced pressure were performed in the same manner and conditions as described above.
The core layer-forming resin varnish B obtained above is applied and dried in the same manner as described above on the non-treated surface of a PET film (trade name: Cosmo Shine A1517, manufactured by Toyobo Co., Ltd., thickness: 16 μm). Next, a release PET film (trade name: PUREX A31, Teijin DuPont Film Co., Ltd., thickness: 25 μm) is attached as a protective film so that the release surface is on the resin side, and a resin film for forming a core layer is attached. Obtained. Here, the gap of the coating machine was adjusted so that the film thickness after curing was 50 μm.

[Step (A)]
On the base material (FR-4, manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-679F (b), thickness: 0.6 mm), an enlarged wiring pattern 5a wider than a predetermined wiring pattern is formed. Formed.

[Step (B)]
The resin surface of the resin film for forming the lower cladding layer 2 obtained above is a base material (FR-4, manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-679F (b), thickness: 0.6 mm). Using a vacuum pressurizing laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) on the enlarged wiring pattern 5a side, after vacuuming to 500 Pa or less, conditions of pressure 0.4 MPa, temperature 70 ° C., pressurization time 30 seconds And thermocompression bonded. Next, ultraviolet rays (wavelength 365 nm) are applied at 0.8 J / cm from the resin film side for forming the lower cladding layer 2 through an ultraviolet exposure machine (EXM-1172, manufactured by Oak Manufacturing Co., Ltd.) through a negative photomask having a width of 50 μm. ² and then post-exposure heating at 80 ° C. for 12 minutes. Thereafter, the PET film which is the carrier film of the resin film for forming the lower cladding layer 2 was peeled off, and the pattern shape of the lower cladding layer 2 was developed in the opening of the enlarged wiring pattern 5a using a developer (cyclohexanone). Then, it wash | cleaned using the washing | cleaning liquid (isopropanol), and heat-dried at 100 degreeC for 10 minute (s).

[Step (C)]
Using a roll laminator (HLM-1500, manufactured by Hitachi Chemical Technoplant Co., Ltd.), the resin surface of the core layer-forming resin film is placed on the lower clad layer 2 and the enlarged wiring pattern 5a. Lamination was performed under the condition of 2 m / min. Next, through a negative photomask with a width of 50 μm, ultraviolet rays (wavelength 365 nm) are irradiated with 0.8 J / cm ² from the core layer forming resin film side by an ultraviolet exposure machine (EXM-1172, manufactured by Oak Manufacturing Co., Ltd.). Subsequently, post-exposure heating was performed at 80 ° C. for 12 minutes. Thereafter, the PET film which is the carrier film of the resin film for forming the core layer is peeled off and used for optical signal transmission using a developer (propylene glycol monomethyl ether acetate / N, N-dimethylacetamide = 7/3, mass ratio). The core pattern 3 and the resist core pattern 4 were developed. Then, it wash | cleaned using the washing | cleaning liquid (isopropanol), and heat-dried at 100 degreeC for 10 minute (s).

[Step (D)]
The resin surface of the resin film for forming the upper clad layer 6 is reduced to 500 Pa or less using a vacuum pressure laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) on the optical signal transmission core pattern 3 and the resist core pattern 4. After evacuation, thermocompression bonding was performed under the conditions of a pressure of 0.4 MPa, a temperature of 70 ° C., and a pressurization time of 30 seconds.

[Step (D ′)]
Next, ultraviolet light (wavelength 365 nm) was irradiated with 3.0 J / cm ² from the resin film side for forming the upper cladding layer 6 through the negative photomask having a width of 50 μm by the ultraviolet exposure machine, and then at 80 ° C., 12 Heating was performed after a minute exposure. Thereafter, the PET film which is a carrier film of the resin film for forming the upper clad layer 6 is peeled off, and using the developer (cyclohexanone), the resist core pattern 4 and the enlarged wiring pattern 5a are exposed so that the upper clad layer 6 is exposed. The pattern shape was developed. Then, it wash | cleaned using the washing | cleaning liquid (isopropanol), and heat-dried at 100 degreeC for 10 minute (s).

[Step (E)]
A portion of the enlarged wiring pattern 5a where the resist core pattern 4 is not laminated is removed by etching to produce a photoelectric composite substrate.
The amount of positional deviation between the lower clad layer and the enlarged wiring pattern (not shown) remaining on the substrate and the core pattern formed on the lower clad layer was measured and found to be 7.5 μm. The amount of positional deviation between the wiring pattern formed in the opening of the lower cladding layer and the core pattern formed on the lower cladding layer was measured and found to be 0 μm.

Example 2
After the steps (A) to (C), etching is performed in the same manner as in the step (E), and then the resin surface of the upper clad layer 6 forming resin film is formed on the optical signal transmission core pattern 3 and the resist core. A vacuum pressurization type laminator (manufactured by Meiki Seisakusho Co., Ltd., MVLP-500) is used on the pattern 4 and the enlarged wiring pattern 5a. The thermocompression bonding was performed under the following conditions.
The amount of positional deviation between the lower clad layer and the enlarged wiring pattern (not shown) remaining on the substrate and the core pattern formed on the lower clad layer was measured and found to be 8 μm. When the amount of positional deviation between the wiring pattern formed in the opening of the lower cladding layer and the core pattern formed on the lower cladding layer was measured, it was 0.1 μm.

  The photoelectric composite substrate and the photoelectric composite module obtained by the manufacturing method of the present invention can be applied to various fields such as various optical devices and optical interconnections.

DESCRIPTION OF SYMBOLS 1 Base material 2 Lower clad layer 3 Optical signal transmission core pattern 4 Resist core pattern 5 Wiring pattern 5a Enlarged wiring pattern 6 Upper clad layer 10 Photoelectric composite substrate

Claims (12)

On a substrate, patterned lower cladding layer, an optical signal transmitting core pattern, wiring pattern, a resist core pattern having a portion of the wiring pattern and the same shape, and an optical-electrical composite having a top cladding layer An optoelectric composite substrate, wherein the wiring pattern is provided in a pattern-shaped opening of a lower clad layer and is sandwiched between a base material and a resist core pattern in a stacking direction .   The photoelectric composite substrate according to claim 1, wherein the resist core pattern and the wiring pattern are exposed to the outside.   3. The photoelectric composite substrate according to claim 1, wherein the resist core pattern is made of the same material as the optical signal transmission core pattern.   The photoelectric composite substrate according to claim 1, wherein the wiring pattern is in contact with the resist core pattern. (A) a step of forming an enlarged wiring pattern on the substrate, (B) a step of forming a lower clad layer patterned in the opening of the enlarged wiring pattern, and (C) an optical signal transmission on the lower clad layer to form a core pattern, on enlarged wiring pattern to form laminating a narrow resist core pattern width than the enlarged wiring pattern, the upper cladding layer so as to cover the (D) an optical signal transmitting core pattern The photoelectric composite substrate according to claim 1, further comprising: a step of forming a wiring pattern by removing a portion of the enlarged wiring pattern on which the resist core pattern is not laminated. Production method.   The process of (A) to (D), (D ′) patterning the upper cladding layer, exposing the resist core pattern and the enlarged wiring pattern, and the process (E) in this order. A method of manufacturing a composite substrate.   The method for producing an optoelectric composite substrate according to claim 5, wherein the step (A) to the step (C), the step (E), and the step (D) are performed in this order.   The method for manufacturing a photoelectric composite substrate according to claim 5, wherein the step (E) is performed by an etching process. (A) a step of forming an enlarged wiring pattern on the substrate, (B ′) a step of forming a patterned lower cladding layer on the enlarged wiring pattern, and (C) an optical signal transmission core on the lower cladding layer. to form a pattern, and a step of laminating a narrow resist core pattern width than the enlarged wiring pattern on the enlarged wiring pattern, and forming an upper cladding layer to cover the (D) an optical signal transmitting core pattern And (E) forming a wiring pattern by removing a portion of the enlarged wiring pattern where the resist core pattern is not laminated, and manufacturing the photoelectric composite substrate according to claim 1. .   Step (A), Step (B ′), Step (C), Step (D), (D ′) Patterning the upper cladding layer to expose the resist core pattern and the enlarged wiring pattern, Step (E) The manufacturing method of the optoelectric composite substrate according to claim 9 performed in this order.   The manufacturing method of the photoelectric composite board | substrate of Claim 9 which performs a process (A), a process (B '), a process (C), a process (E), and a process (D) in this order.   The method for producing an optoelectric composite substrate according to claim 9, wherein the step (E) is performed by an etching process.

Images