JP5754130B2 - 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 intensive studies, the present inventors formed a resist core pattern inside the pattern-shaped opening of the lower cladding layer when forming the optical signal transmission core pattern, and used this as a resist for wiring. It has been found that the above problems can be solved by a photoelectric composite substrate obtained by forming a pattern, and the present invention has been completed.
That is, the present invention
1. An optical / electrical composite substrate having an optical signal transmission core pattern, a resist core pattern, a wiring pattern, a patterned lower clad layer, and an upper clad layer, wherein the wiring pattern and A photoelectric composite substrate, wherein the resist core pattern is embedded, and the wiring pattern is sandwiched between the resist core patterns in any one direction orthogonal to the stacking direction;
2. 2. The photoelectric composite substrate according to 1 above, wherein the resist core pattern is made of the same material as the optical signal transmission core pattern.
3. The photoelectric composite substrate according to 1 or 2, wherein the wiring pattern is in contact with the resist core pattern,
4). (A) forming and patterning a lower clad layer on the support; and (B) forming an optical signal transmission core pattern on the lower clad layer and inside the pattern-shaped opening of the lower clad layer. Forming a resist core pattern having a narrower opening; (C) forming a wiring pattern in the opening of the resist core pattern; and (D) covering the optical signal transmission core pattern. The method for producing an optoelectric composite substrate according to any one of the above 1 to 3, comprising a step of forming an upper clad layer on the substrate and (E) a step of removing the support and exposing the wiring pattern,
5. The support has a first metal foil on a substrate, and in the step (C), a pattern is formed on the first metal foil using the pattern shape of the resist core pattern as a resist to form a wiring pattern. 5. The method for producing a photoelectric composite substrate according to 4 above, and The support further has a second metal foil between the substrate and the first metal foil, and the step (E) is (E-1) at the interface between the first metal foil and the second metal foil. The method for producing an optoelectric composite substrate according to the above 4 or 5, comprising a step of peeling and removing the second metal foil and the base material, and (E-2) a step of removing the first metal foil.
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 optoelectric composite board | substrate of this invention. It is sectional drawing which shows each process of the manufacturing method of the photoelectric composite board | substrate of this invention.

As shown in FIG. 1, the photoelectric composite substrate of the present invention has an optical signal transmission core pattern 3, a resist core pattern 4, a wiring pattern 5, a patterned lower clad layer 2, and an upper clad layer 6. The wiring pattern 5 and the resist core pattern 4 are embedded in the pattern-shaped opening of the lower cladding layer 2, and the wiring pattern 5 is sandwiched between the resist core pattern 4 in any one direction orthogonal to the stacking direction. It is characterized by.
Here, that the wiring pattern 5 and the resist core pattern 4 are embedded in the pattern-shaped opening of the lower cladding layer 2 means that, for example, at least a part of each of the wiring pattern 5 and the resist core pattern 4 is formed. The state which is formed inside the opening part of the pattern shape of the lower clad layer 2 is shown.
The wiring pattern 5 being sandwiched between the resist core patterns 4 means, for example, that at least a part of the wiring pattern 5 exposed on the lower clad layer 2 side of the photoelectric composite substrate of the present invention is bordered. Shows a state in which the resist core pattern 4 is formed. More preferably, the wiring pattern 5 embedded in the opening of the lower cladding layer 2 is in the same layer as the lower cladding layer 2. The state clamped by at least one part is shown.

  In addition, as shown in FIG. 2, the method for manufacturing an optoelectric composite substrate according to the present invention includes: (A) a step of forming a lower clad layer 2 on a support 1 and patterning; Forming a core pattern 3 for transmitting an optical signal and forming a resist core pattern 4 having a narrower opening inside a pattern-shaped opening of the lower cladding layer 2; and (C) resist A step of forming the wiring pattern 5 in the opening of the core pattern 4 for use, (D) a step of forming the upper cladding layer 6 so as to cover the core pattern 3 for transmitting an optical signal, and (E) removing the support 1. And a step of exposing the wiring pattern 5.

<Process (A)>
In the step (A), the lower clad layer 2 is formed on the support 1 and patterned.
(Support)
The support 1 is preferably one that can be easily removed in the step (E). When the support 1 having the first metal foil 1a on the substrate 1c is used, pattern plating is performed using the resist core pattern 4 as a resist in the step (C), so that the support 1 is sandwiched between the resist core patterns 4. This is preferable because the formed wiring pattern 5 can be formed. Furthermore, when what has the 2nd metal foil 1b between the base material 1c and the 1st metal foil 1a is used, in the interface of 1st metal foil 1a and the 2nd metal foil 1b in a process (E). It is more preferable because the second metal foil 1b and the substrate 1c can be easily removed by peeling.

(First metal foil)
The first metal foil 1a only needs to function as a seed layer for supplying current when pattern plating is performed using the resist core pattern 4 as a resist in the step (C), and the material and thickness are not particularly limited. From the viewpoint of versatility and handleability, the material is preferably copper foil or aluminum foil, and the thickness is preferably 1 to 18 μm. Furthermore, when the wiring pattern 5 is exposed in the step (E), it is removed by etching or the like.
Moreover, it is preferable to provide a release layer for stabilizing the peel strength at the interface at the interface with the substrate 1c or the interface with the second metal foil 1b provided as necessary. Is preferable to have a stable peel strength even when the heating and pressurization are repeated a plurality of times when laminated with an insulating resin. As such a release layer, a metal oxide layer or an organic agent layer disclosed in Japanese Patent Application Laid-Open No. 2003-181970, or a Cu—Ni—Mo alloy disclosed in Japanese Patent Application Laid-Open No. 2003-094553 is used. The thing consisting of is mentioned.

  As for the 1st metal foil 1a, what provided the unevenness | corrugation whose average roughness (Ra) is 0.08-0.6 micrometer in advance on the surface is desirable. Thereby, adhesion and resolution with the patterned lower cladding layer 2 and resist core pattern 4 can be improved, which is advantageous for forming a high-density circuit. When Ra is 0.08 μm or more, the adhesion to the lower cladding layer 2 and the resist core pattern 4 is improved, and when Ra is 0.6 μm or less, the lower cladding layer 2 and the resist core pattern 4 are easy to follow. As a result, the adhesion is improved. Here, the average roughness (Ra) is an average roughness (Ra) defined by JIS B 0601 (2001), and can be measured using a stylus type surface roughness meter or the like.

(Base material)
The substrate 1c is not particularly limited as long as it has sufficient strength to withstand the lamination of each layer in the steps (A) to (D). 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 1c, a substrate having flexibility and toughness, for example, a clad layer forming resin film and a core layer forming resin film, which will be described later, may be used as the substrate.

(Second metal foil)
The second metal foil 1b is not particularly limited in material and thickness as long as it is physically peelable at the interface with the first metal foil 1a. However, in terms of versatility and handleability, the material is copper foil. And aluminum foil are preferable, and the thickness is preferably 1 to 35 μm.

(Lower cladding layer)
The formation method of the lower clad layer 2 is not particularly limited and may be a known method. For example, the lower clad layer 2 is formed by applying a clad layer forming resin on the support 1 or laminating a clad layer forming resin film. can do. 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 cladding layer forming resin may be the same or different in the components contained in the resin composition in the lower cladding layer 2 and the upper cladding layer 6. The refractive indexes 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.
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. For example, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylacetamide, propylene glycol monomethyl ether, propylene glycol A solvent such as 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 depending on the properties of the clad layer forming resin to be used.

<Process (B)>
In the step (B), the optical signal transmission core pattern 3 is formed on the lower clad layer 2, and the resist core pattern having a narrower opening inside the pattern-shaped opening of the lower clad layer 2. 4 is formed.
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, a core layer having a higher refractive index than this layer is formed on the lower cladding layer 2. Thereafter, it can be formed in the same manner as the above-described patterning method.
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 resin film for forming the clad layer.

The formation method of the core layer laminated | stacked on the lower clad layer 2 is not specifically limited, For example, what is necessary is just to form by the application | coating of the resin for core layer formation, or the lamination of the resin film for core layer formation.
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 as that used for the cladding layer forming resin.
In the case of application, the method is not limited, and the resin may be applied by a conventional method as described above.

Hereinafter, the resin film for core layer formation used for lamination is explained in full 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 (C)>
In the step (C), the wiring pattern 5 is formed in the opening of the resist core pattern 4.
As a method for forming the wiring pattern 5, as described above, a method of performing pattern plating using the resist core pattern 4 as a resist by using the support 1 having the first metal foil 1 a on the substrate 1 c is preferable. Used. As the pattern plating, electroplating using copper sulfate is preferably used. The wiring pattern 5 thus formed comes into contact with the resist core pattern 4.
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 is also formed in the opening of the resist core pattern 4 in the step (C), so that the alignment with the optical signal transmission core pattern 3 is good.
Through the steps (A) to (C), the lower cladding 2 having a relatively wide opening, the resist core pattern 4 having a relatively narrow opening, and the opening of the resist core pattern 4 are formed. Since the wiring pattern to be embedded is formed, in the photoelectric composite substrate of the present invention obtained as a result, the resist core pattern 4 is formed of the wiring pattern 5 and the lower cladding layer 2 in any one direction orthogonal to the stacking direction. It is pinched by the pattern shape.

<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 (E)>
In the step (E), the support 1 is removed and the wiring pattern 5 is exposed.
When the support body 1 has the 1st metal foil 1a, the 2nd metal foil 1b, and the base material 1c in this order, and a process (E) has the following process (E-1) and a process (E-2), This is preferable because the wiring pattern 5 can be efficiently exposed and problems such as the wiring pattern 5 falling off hardly occur.

<Process (E-1)>
At a process (E-1), it peels in the interface of the 1st metal foil 1a and the 2nd metal foil 1b, and removes the 2nd metal foil 1b and the base material 1c.
By adjusting the peel strength at the interface between the first metal foil 1a and the second metal foil 1b and physically peeling at the interface, the peeling work can be easily performed.

<Process (E-2)>
In the step (E-2), the first metal foil 1a is removed.
Etching is preferably used as a method for removing the first metal foil 1a. By removing the first metal foil 1a, the wiring pattern 5 is exposed, and various components can be mounted thereon.

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
[Production of support]
First copper foil (thickness: 3 μm), second copper foil (thickness: 9 μm) and base material (FR-4, manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-679F (b), thickness : 0.6 mm) was prepared in this order. On the surface of the first copper foil, irregularities having an average roughness (Ra) of 0.08 to 0.6 [mu] m are provided in advance, and Cu-Ni-Mo can be physically separated from the second copper foil. A release layer made of an alloy was formed.
The base material, the first copper foil, and the second copper foil were obtained by superimposing two metal foils on the base material, and heating and pressurizing them by hot pressing to laminate and integrate them to obtain a support 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)]
The resin surface of the resin film for forming the lower clad layer 2 obtained above is pressure 0 using a roll laminator (HLM-1500, manufactured by Hitachi Chemical Technoplant Co., Ltd.) on the first copper foil of the support 1 obtained above. Lamination was performed under conditions of 4 MPa, a temperature of 50 ° C., and a laminating speed of 0.2 m / min. 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 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 (B)]
A roll laminator (HLM-1500, manufactured by Hitachi Chemical Technoplant Co., Ltd.) is used as the resin surface of the core layer-forming resin film on the lower clad layer 2 having a pattern shape. 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 resist core pattern 4 having a narrower opening inside the pattern-shaped opening of the core pattern 3 and the lower cladding layer 2 was developed. Then, it wash | cleaned using the washing | cleaning liquid (isopropanol), and heat-dried at 100 degreeC for 10 minute (s).

[Step (C)]
The resist core pattern 4 remaining on the first copper foil was used as a resist, and a copper pattern was used to form a wiring pattern 5 having a thickness of 15 μm in the pattern-shaped opening.

[Step (D)]
Using the roll laminator (HLM-1500, manufactured by Hitachi Chemical Technoplant Co., Ltd.) on the resin surface of the resin film for forming the upper clad layer 6 on the optical signal transmission core pattern 3 and the resist core pattern 4, a pressure of 0.4 MPa, Lamination was performed under the conditions of a temperature of 50 ° C. and a laminating speed of 0.2 m / min. Next, ultraviolet rays (wavelength 365 nm) are irradiated with 3.0 J / cm ² by the above ultraviolet exposure machine, the entire surface of the upper cladding layer 6 is exposed and photocured, and then heat-treated at 160 ° C. for 1 hour. The clad layer 6 was cured. Thereafter, the polyamide film which is the carrier film of the resin film for forming the upper clad layer 6 was peeled off.

[Step (E-1)]
The support 1 was physically peeled off at the interface between the first copper foil and the second copper foil, and the second copper foil and the substrate were removed.

[Step (E-2)]
The first copper foil was removed by etching to produce a photoelectric composite substrate.
It was 0.2 micrometer when the positional offset amount of the core pattern and electrical wiring pattern of the obtained optical waveguide was measured.

Comparative Example 1
In Example 1, after forming an electrical wiring having the same pattern as Example 1 using a dry film resist (trade name: Photec, manufactured by Hitachi Chemical Co., Ltd.), the dry film resist was peeled off and obtained above. Using a roll laminator (HLM-1500, manufactured by Hitachi Chemical Technoplant Co., Ltd.) on the wiring pattern, the resin surface of the 30 μm lower clad layer forming film is pressure 0.4 MPa, temperature 50 ° C., laminating speed 0.2 m / min. Lamination was performed under the following conditions. Thereafter, a core pattern and an upper clad layer were formed in the same manner as in Example 1.
The amount of positional deviation between the core pattern and the electric wiring pattern of the obtained optical waveguide was measured and found to be 7.8 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 Support 1a 1st metal foil 1b 2nd metal foil 1c Base material 2 Lower clad layer 3 Core pattern for optical signal transmission 4 Core pattern for resist 5 Wiring pattern 6 Upper clad layer 10 Photoelectric composite substrate

Claims (6)

An optical / electrical composite substrate having an optical signal transmission core pattern, a resist core pattern, a wiring pattern, a patterned lower cladding layer, and an upper cladding layer covering the wiring pattern, the pattern-shaped opening of the lower cladding layer And a wiring pattern and a resist core pattern embedded therein, and the wiring pattern is sandwiched between the resist core pattern in an arbitrary direction orthogonal to the stacking direction.   The optoelectric 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) forming and patterning a lower cladding layer on the support; and (B) using the same photomask , forming an optical signal transmission core pattern on the lower cladding layer, Forming a resist core pattern having a narrower opening inside the pattern-shaped opening; (C) forming a wiring pattern in the opening of the resist core pattern; and (D) light. The photoelectric composite according to claim 1, further comprising: forming an upper clad layer so as to cover the signal transmission core pattern; and (E) removing the support to expose the wiring pattern. A method for manufacturing a substrate.   The support has a first metal foil on a substrate, and in the step (C), a pattern is formed on the first metal foil using the pattern shape of the resist core pattern as a resist to form a wiring pattern. The method for producing a photoelectric composite substrate according to claim 4.   The support further has a second metal foil between the substrate and the first metal foil, and the step (E) is (E-1) at the interface between the first metal foil and the second metal foil. The method for producing an optoelectric composite substrate according to claim 4 or 5, comprising a step of peeling and removing the second metal foil and the base material, and a step (E-2) of removing the first metal foil.

Images