JP2005215529A - Device with optical waveguide structure and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for obtaining an optical waveguide structure by using a near-infrared-ray setting composition and a device equipped with the optical waveguide structure having a core part made of near-infrared-ray setting resin obtained by the same method. <P>SOLUTION: This device 100 is equipped with an optical waveguide structure 10 having a core part 11 which is made of the near-infrared-ray setting resin having set and propagates light and a clad part 12 which surrounds the core part 11. Another device 100 is equipped with an optical waveguide structure 10 having a core part 11 which sets with near infrared rays and propagates light and a clad part 12 which surrounds the core part 11. This manufacturing method includes an unset layer forming stage of forming an unset layer made of a near-infrared-ray setting composition cured into near-infrared-ray setting resin and a core part forming stage of forming a core part by irradiating the unset layer with near infrared rays. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a device with an optical waveguide structure and a manufacturing method thereof. More specifically, the present invention relates to a device having an optical waveguide structure using a near-infrared curable resin and a manufacturing method thereof.

  Conventionally, in an information processing field and an information communication field, many processes using electric signals have been performed. However, progress in the information processing field and the information communication field is remarkable, and the amount of data to be handled is increasing, and it is predicted that it will continue to increase in the future. Along with this, there is a demand for higher communication speed. For this reason, a shift to information processing and information communication using an optical signal having a processing speed larger than that of an electrical signal is desired. In particular, in recent years, not only signal transmission paths with long transmission distances typified by optical communication cables and dedicated devices associated therewith, but also short signal transmission paths such as connections of boards and electronic components in general-purpose electronic equipment, Migration from electrical transmission media to optical transmission media is being considered. However, when a device including an optical transmission medium is manufactured, extremely high position accuracy is required to reduce transmission loss as much as possible, which makes the manufacturing process complicated and leads to high costs.

  An optical waveguide is known as an optical transmission medium used in the new information processing and information communication, and an organic type and an inorganic type are known as the optical waveguide. Of these, organic materials are promising because they are excellent in material properties such as processability and flexibility, and in terms of cost. For this organic optical waveguide, many photo-curing resins are used, and these are ultraviolet-curing resins. On the other hand, as the near infrared curable resin, techniques disclosed in the following Patent Documents 1 to 3 are known.

JP 2003-195498 A JP 2003-233178 A JP-A-9-137089

However, in the said patent documents 1-3, the suggestion regarding an optical waveguide structure is not recognized.
This invention is made | formed in view of the said viewpoint, and it aims at providing the device with an optical waveguide structure formed using near-infrared curable resin, and its manufacturing method. Furthermore, it aims at providing the device with an optical waveguide structure in which the transmission loss was suppressed formed using the near-infrared light emitting element used for optical communication, and its manufacturing method.

  The present inventors have studied an optical waveguide structure formed using the ultraviolet curable resin, and thought that transmission loss can be efficiently reduced by improving accuracy in the manufacturing process. In addition, it has been found that there is a transmission loss caused by using an ultraviolet curable resin. That is, normally, near-infrared light is used in optical communication, but ultraviolet light is used as light for forming the optical waveguide structure. For this reason, for example, when an optical waveguide structure is to be formed by self-forming means that has been attracting attention due to high alignment accuracy, the ultraviolet light emitting element is first attached only to form the optical waveguide structure. After that, it is necessary to replace the ultraviolet light emitting element with a near infrared light emitting element used for communication. Therefore, the merit of the self-forming means may not be fully utilized. Based on this finding, the present inventors studied the formation of an optical waveguide using near infrared rays, and based on this, completed the present invention.

That is, the present invention is as follows.
(1) A device with an optical waveguide structure comprising an optical waveguide structure made of a cured near infrared curable resin and having a core portion through which light propagates and a clad portion surrounding the core portion.
(2) A device with an optical waveguide structure comprising an optical waveguide structure having a core portion that is cured by near infrared rays and propagates light, and a clad portion that surrounds the core portion.
(3) The light emitting element that emits near infrared rays is provided on at least one end side of the core portion, and the core portion is cured by the near infrared rays emitted from the light emitting element. A device with an optical waveguide structure described in 1.
(4) The optical system according to any one of (1) to (3), further including an optical path conversion unit that reflects the light propagating in the core unit, wherein the core unit is bent at the optical path conversion unit. Device with optical waveguide structure.
(5) The device with an optical waveguide structure according to any one of (1) to (4), wherein the core portion and the cladding portion are made of the same kind of resin.
(6) The device with an optical waveguide structure according to any one of (1) to (5), wherein the core portion includes an acrylic resin.
(7) The device with an optical waveguide structure according to any one of (1) to (5), wherein the core portion includes an epoxy resin.
(8) A method of manufacturing a device with an optical waveguide structure comprising an optical waveguide structure comprising a core portion made of a cured near-infrared curable resin and propagating light, and a cladding portion surrounding the core portion,
An uncured layer forming step of forming an uncured layer comprising a near-infrared curable composition which is cured to become a near-infrared curable resin;
A core part forming step of forming the core part by irradiating the uncured layer with near-infrared rays.
(9) A method for manufacturing a device with an optical waveguide structure according to (8) above,
After the uncured layer forming step and before the core portion forming step, a light emitting element disposing step of disposing a light emitting element emitting near infrared rays on the uncured layer is provided.
In the core part forming step, an optical waveguide that irradiates the near infrared ray using the light emitting element and selectively cures a portion of the uncured layer irradiated and transmitted with the near infrared ray to form the core part. A method for manufacturing a structured device.
(10) A method for manufacturing a device with an optical waveguide structure according to (8) above,
In the core part forming step, a method of manufacturing a device with an optical waveguide structure, wherein the core part is formed by performing a photolithography method using the near infrared ray on the uncured layer.

According to the device with an optical waveguide structure according to the first and second aspects, the circuit can be operated by light.
When the core part is cured by near infrared rays emitted from the light emitting element, the optical element and the core part can be optically connected with high accuracy, and in particular, a circuit with reduced transmission loss can be obtained. it can. In addition, the manufacturing process can be simplified. This is excellent in terms of cost, yield and the like.
When the core portion is bent at the optical path changing portion, an optimal optical path can be obtained, and communication efficiency can be improved and the size can be reduced.
When the core part and the clad part are made of the same kind of resin, the manufacturing process can be simplified. This is excellent in terms of cost, yield and the like.
When the core portion contains an acrylic resin, the device with an optical waveguide structure having a core portion that is excellent in photosensitivity at the time of manufacture and particularly excellent in transparency.
When the core portion contains an epoxy resin, the device with an optical waveguide structure that is particularly excellent in heat resistance, insulation resistance, and water resistance is obtained.
According to the method for manufacturing a device with an optical waveguide structure of the present invention, a circuit that is operated by light efficiently can be obtained.
When the core portion is formed by selectively curing using the light emitting element in the core portion forming step, the optical element and the core portion can be optically connected with high accuracy, particularly transmission. A circuit in which loss is suppressed can be obtained. In addition, the manufacturing process can be simplified. This is excellent in terms of cost, yield and the like.
When the core portion is formed by performing a photolithography method, a planar optical communication circuit pattern can be efficiently formed.

The present invention will be described in detail below.
[1] Device with optical waveguide structure The device with an optical waveguide structure according to the first aspect includes an optical waveguide made of a cured near-infrared curable resin and having a core portion through which light propagates and a cladding portion surrounding the core portion. A structure is provided.

The “optical waveguide structure” includes a core portion and a cladding portion.
The “core part” is a part through which light propagates. A core part consists of hardened near-infrared curable resin. This “near-infrared curable resin” is a resin obtained by curing a near-infrared curable composition to be described later, and is polymerized by irradiation with near-infrared rays (“polymerization” includes “copolymerization” and “homopolymerization”). And the like (which means that the polymerization has further progressed). The near-infrared curable resin referred to in the present invention includes a thermosetting polymer ("polymer" includes "copolymer" and "homopolymer", the same shall apply hereinafter), a thermoplastic polymer, and the like. Further, the presence or absence of a three-dimensional structure in the resin is not limited.

  The kind of near-infrared curable resin which comprises a core part is not specifically limited. For example, acrylic resin, epoxy resin, polyimide resin, fluororesin, bismaleimide resin, polyphenylene ether resin, phenol resin, silicone resin, urethane resin, polyester resin, phenoxy resin and polyolefin resin Etc. can be used. In addition, each halogenated resin in which at least some of the hydrogen atoms included in each of these resins are substituted with halogen atoms, and each deuterated resin in which at least some of the hydrogen atoms included in these resins are replaced with deuterium atoms Etc. can be used. These resins may be used alone or in combination of two or more.

  Among these, acrylic resins, epoxy resins, halogenated acrylic resins, halogenated epoxy resins, deuterated acrylic resins, and deuterated epoxy resins are preferable. This is because these resins have excellent near-infrared transmittance. Among these, fluorinated acrylic resins, fluorinated epoxy resins, deuterated acrylic resins, and deuterated epoxy resins are more preferable. These resins can be connected with little transmission loss particularly in the production method according to the present invention described later. Moreover, since the material itself is excellent in the near infrared transmittance, transmission loss can be effectively suppressed. Each halogenated resin is preferably substituted with at least one of F, Cl and Br, and particularly preferably substituted with F.

Regardless of the type and number of near-infrared curable resins constituting the core portion, the core portion may have a substantially uniform refractive index or may have portions with different refractive indexes. That is, the substantially uniform refractive index throughout the entire case is, for example, a case where the refractive index changes abruptly at the interface between the core portion and the cladding portion. In addition, the phrase “having a portion having a different refractive index” means, for example, a case where the core portion has the maximum refractive index and the refractive index becomes smaller as it approaches the cladding portion. However, the refractive index may be different or the same between different types of resins, and even a resin derived from the same monomer changes depending on the degree of polymerization. Therefore, the uniform refractive index portion and the different refractive index portion may be obtained from the same kind of resin or from different kinds of resins.
Moreover, the transmission characteristic with respect to the light of a core part is not specifically limited, For example, what kind of light can be permeate | transmitted, such as infrared rays (a near infrared ray is included), visible light, and an ultraviolet-ray, may be used. Especially, it is preferable that it is what can permeate | transmit a near infrared ray (0.7-25 micrometers) especially, and it is more preferable that it is a thing suitable for transmission of a near infrared ray (0.7-2 micrometers).

Although the form of a core part is not specifically limited, Usually, it has an end surface which can input and output light. The number of the end faces is not particularly limited, but is usually two or more, and at least one can be used as a light entrance surface and at least one other can be used as a light exit surface. In the case of having three or more end faces, the core portion can have two or more light incident surfaces and / or light exit surfaces.
The planar shape is not particularly limited, and may be linear, curved, may have a bent portion, or may have a branch. Furthermore, it can also be set as the trumpet shape etc. which spread toward an end surface in the vicinity of the end. Among these, the bent portion means a portion where the optical path is bent. By having the bent portion, an optimal optical path can be obtained, and communication efficiency can be improved and the size can be reduced. This bent part may have only one place in a series of core parts, or may have two or more places. The optical path changing part in this bent part will be described later.
Further, the cross-sectional shape (cross-section with respect to the light propagation direction) is not particularly limited, and may be a quadrangle (such as a square or a rectangle) or a circle. Moreover, it can also be made into polygons other than a rectangle, and cross-sectional shape which is not perfect circles like an ellipse etc. may be sufficient.

  As described above, the near-infrared curable resin is a resin obtained by polymerizing a near-infrared polymerization composition by irradiation with near-infrared rays. The core part may be obtained by polymerizing the near infrared polymerization composition by any method, and examples thereof include the following core parts (1) to (3). That is, (1) a near-infrared light emitting element is disposed on an uncured layer comprising a near-infrared curable composition, and then a near infrared light is emitted from the near-infrared light emitting element to selectively select a desired portion of the uncured layer. A core obtained by curing, and (2) obtained by subjecting an uncured layer comprising a near-infrared curable composition to a desired portion of the uncured layer by subjecting the uncured layer to a photolithography method using near infrared rays. And (3) a core portion obtained by drawing with a near-infrared laser so that a desired portion of an uncured layer made of the near-infrared curable composition is cured.

  Among these, the core part (1) is preferable. This is because the core portion can obtain a highly accurate connection with a near-infrared light emitting element, in particular, with reduced transmission loss. That is, the core part made of a conventionally known ultraviolet curable resin is formed by using the ultraviolet light emitting element, and then the ultraviolet light emitting element used only for forming the core part is removed, and then the actual communication is performed. A near-infrared light-emitting element that emits light is positioned with high accuracy and attached, and the core portion and the near-infrared light-emitting element are connected. On the other hand, the core part of (1) is directly formed using a near-infrared light emitting element. For this reason, it is difficult to cause a transmission loss, and a large cost is not required to suppress the transmission loss. That is, it is possible to obtain a connection in which conduction loss due to position accuracy and the like is suppressed more efficiently and more reliably.

There are no particular limitations on the type of near-infrared light emitting element used when forming the core part of the above (1), and it can be appropriately determined depending on the configuration of the near-infrared polymerization composition used. Examples of the light emitting element include a surface emitting laser (VCSEL), a light emitting diode (LED), and a semiconductor laser diode (LD). These may use only 1 type and may use 2 or more types together.
Since the core in the device with an optical waveguide structure of the present invention is cured by near infrared rays, the core is less damaged and more reliable than the core cured by ultraviolet rays. Since ultraviolet irradiation gives higher energy than near-infrared irradiation, there is a possibility that the resin may be oxidized or possibly decomposed and altered. In addition, when selecting a resin, it is necessary to select a resin having a characteristic capable of withstanding ultraviolet irradiation. However, the core by near infrared curing and the resin therefor are excellent in that there are no such restrictions.

The “cladding portion” is a portion surrounding the core portion. The clad part is a part that can reflect light propagating in the core part at the interface with the core part. For example, the clad portion can obtain this effect by making the refractive index smaller (usually 0.2% or more) than the core portion.
The material constituting the clad portion is not particularly limited. An inorganic material may be used for this clad part, but an organic material is used because it is easy to process and it is easier to match the thermal expansion coefficient with the near infrared curable resin constituting the core part. It is preferable. As the organic material, any of the resins mentioned as the near-infrared curable resin can be used regardless of whether the resin is cured using near-infrared rays. However, the core part and the clad part may be made of the same resin or different resins.
Moreover, the shape of a clad part is not specifically limited. That is, for example, as illustrated in FIG. 6, all the portions except for the core portion in the predetermined layer and portion may be formed as the cladding portion, and in the predetermined layer and portion as illustrated in FIG. 7. As a part, a core part and a clad part may be provided, and the clad part may be formed so as to cover the surface of the core part thinly. Further, the cross-sectional shape (cross-section with respect to the light propagation direction) is not particularly limited, and may be a cross-sectional shape similar to that of the core portion or a different shape.

  As described above, the core portion can be provided with a bent portion as required. However, since the optical waveguide structure in this device has a cladding portion, the optical path can be converted (bended) without an optical path changing portion. )can do. However, an angle at which sufficient reflection from the clad part is not obtained due to a difference in refractive index between the clad part and the core part may occur, and light may leak from the core part. For this reason, it is preferable to have an optical path changing part (for example, when the refractive index difference between the core part and the clad part is 0.3% and the optical path is changed at an angle of 7 degrees or more). That is, it is preferable to have a structure that has an optical path changing portion that reflects light propagating in the core portion and is bent at the optical path changing portion. This optical path conversion part may have only one in an optical waveguide structure, and may have two or more.

  The “optical path changing part” is a part that can reflect light propagating in the core part. By having the optical path conversion unit, it is possible to efficiently convert the optical path while preventing light leakage. The configuration, shape, and the like of the optical path conversion unit are not particularly limited. That is, for example, by providing an inclined reflective surface (for example, using one surface such as a V-shaped groove, a V-shaped convex portion, a trapezoidal groove, and a trapezoidal convex portion) as illustrated in 43 to 45 of FIG. Can be configured. Only one reflection surface may be provided in one optical path conversion unit, or two or more reflection surfaces may be provided. The reflective surface may be formed of any material as long as it can reflect light. For example, the reflective surface is preferably formed of a material having high reflectivity such as metal. Copper, rhodium, nickel and the like are preferable. These may use only 1 type and may use 2 or more types together.

  The method for forming these optical path conversion units 43 to 45 is not particularly limited. For example, the optical path conversion unit 43 in FIG. 8 can be obtained by pressing a metal block into a desired shape using a capillary or the like. The optical path conversion unit 44 in FIG. 8 can be obtained by providing a notch (concave portion) using a dicing blade or the like in the clad portion and forming a reflective layer 47 made of metal or the like in the notch. In the optical path conversion parts 45 and 46 of FIG. 8, after providing the reflective layer 47 in the notch (concave part) as described above, the inside of the notch is filled using the same material as the clad part or some different material. Can be obtained. 8 can also be obtained by forming a convex portion having an inclined surface with a resin or the like and covering the surface of the convex portion with a reflective layer 47 made of metal or the like.

The device with an optical waveguide structure of the present invention can include other parts in addition to the optical waveguide structure, the light emitting element, and the optical path changing part. Examples of other parts include optical components such as light receiving elements. Furthermore, various electronic parts etc. are mentioned.
Among these, examples of the light receiving element include a pin photodiode (pin PD) and an avalanche photodiode (APD). The light emitting element and the light receiving element may be integrated.
Examples of electronic components include various active components (such as integrated circuit elements and transistors), passive components (such as capacitors, capacitors, and inductors), conversion components (such as filters and transformers), and connection components.
The method for mounting these optical components and electronic components is not particularly limited, and may be wire bonding and / or flip chip bonding.

  Furthermore, the device with an optical waveguide structure can include a conductor portion. In particular, when an optical element such as the light emitting element and the light receiving element is provided, it is preferable to provide a conductor portion. By providing the conductor portion, the optical element can be electrically connected to another electronic component, and the optical waveguide structure, the optical element, the electronic component, and the like can be handled as an integrated object. Further, by providing the conductor portion in the device with the optical waveguide structure, the connection distance between the optical element and the electronic component can be kept short, and the responsiveness can be improved. Furthermore, this contributes to miniaturization of the device with an optical waveguide structure itself.

The type of the conductor portion is not particularly limited, and examples thereof include normal wiring, through-hole conductors, via conductors, wiring patterns that function as resistors, wiring patterns that function as inductors, wiring patterns that function as capacitors, lands, and the like. The arrangement place of these conductor parts is not particularly limited, but can be arranged in the clad, on the surface of the clad part, and in the base part to be described later. Furthermore, the material which comprises a conductor part is not specifically limited, For example, gold | metal | money, silver, copper, platinum, nickel, chromium, titanium, aluminum, tungsten, molybdenum etc. can be used. These may use only 1 type and may use 2 or more types together.
The method for forming the conductor part is not particularly limited. For example, sputtering, ion plating, vapor deposition (including CVD and PVD), vapor deposition and plating, and patterning such as photolithography. Can be obtained in combination with the law.

The optical waveguide structure may exist alone. That is, for example, when the clad portion in the optical waveguide structure has sufficient mechanical strength for a desired purpose, the clad portion functions as a base portion that maintains the shape of the optical waveguide structure.
On the other hand, the optical waveguide structure may include a base portion. That is, for example, when the cladding portion cannot hold the shape of the optical waveguide structure as described above, or even if it can be held, if it is necessary, it is further held detachably and later with other portions. When it is the purpose to be joined, the base portion can be provided in the case. This base part may be joined and integrated with the optical waveguide structure, or may be held in a peelable manner. Furthermore, the base portion may be in direct contact with the optical waveguide structure or may be through another portion.

The material which comprises a base | substrate part is not specifically limited, The composite material etc. which used the organic material, the inorganic material, and both of these are mentioned.
The organic material is not particularly limited. For example, epoxy resin, BT (bismaleimide / triazine) resin, polyimide resin, phenol resin, xylene resin, thermosetting PPE (polyphenylene ether) resin, LCP ( Liquid layer polymer), BCB (benzocyclobutene), polynorbornene and the like. These organic materials may be used alone or in combination of two or more. These resins may also contain various rubbers for modification. Further, the base portion is made of glass cloth, glass nonwoven fabric, resin (polyamide, etc.) cloth, resin (polyamide, etc.) nonwoven fabric, resin (polyamide, etc.) film, PTFE (polytetrafluoroethylene), etc. as a core material. You may have the fluororesin-type core material and metal foil which have a structure.

  The inorganic material is not particularly limited. For example, alumina, quartz, titania, zirconia, garnite, titanate (magnesium titanate, calcium titanate, strontium titanate, barium titanate, etc.), mullite, cordierite, and forte Examples thereof include ceramic materials such as stellite, wollastonite, anorthite, enstatite, diopsite, akermanite, gelenite, and spinel. Furthermore, crystalline or non-crystalline glass-based materials can be mentioned. Examples of the component constituting the glass material include Si, Al, Na, K, Mg, Ca, B, Pb, and Zn. Specific examples include aluminosilicate glass and aluminoborosilicate glass. These ceramic materials and glass materials may be used alone or in combination. When used in combination, a ceramic material can be contained in the glass material as a filler. These inorganic materials may be used alone or in combination of two or more.

  The device with an optical waveguide structure according to the second aspect includes an optical waveguide structure having a core portion that is cured by near-infrared light and propagates light, and a cladding portion that surrounds the core portion. . Each of the core part, the clad part, the optical waveguide structure, the other part, etc. in the present invention can be applied as it is in the device with an optical waveguide structure according to the first aspect.

[2] Method for Producing Device with Optical Waveguide Structure The device with an optical waveguide structure of the present invention may be produced by any method, but a near-infrared curable composition is used in an uncured layer forming step as described later. . Hereinafter, the near-infrared curable composition will be described first.
<1> Near-infrared curable composition The "near-infrared curable composition" is a composition that is polymerized by irradiation with near-infrared rays to become the near-infrared curable resin. Although the component contained in this near-infrared curable composition is not specifically limited, For example, (1) It is set as the composition containing the monomer and / or oligomer which are polymerized and comprise a near-infrared curable resin, and a polymerization initiator. be able to. Moreover, (2) It can be set as the composition which contains the polymerization initiating group which can start superposition | polymerization by irradiation of near infrared rays, and contains the monomer and / or oligomer which are polymerized and comprise a near-infrared curable resin. .
Furthermore, among these, the near-infrared curable composition of the above (1) contains, for example, an α, β-unsaturated ethylene group-containing polymerizable compound described later in (1-1) and a radical generator. It can be a composition (hereinafter simply referred to as “ethylene-based composition”). Moreover, it can be set as the composition (henceforth only an "epoxy type composition") containing the epoxy-type polymeric compound mentioned later in (1-2), and an acid generator. Further, a composition containing an α, β-unsaturated ethylene group-epoxy group-containing polymerizable compound, a radical generator, and an acid generator described later in (1-3) (hereinafter simply referred to as “ethylene epoxy”). System composition)).

(1-1) Ethylene-based composition An ethylene-based composition (including an acrylic composition) is one type of the near-infrared curable composition, and an α, β-unsaturated ethylene group-containing polymerizable compound; And a radical generator.

  The “α, β-unsaturated ethylene group-containing polymerizable compound” is a compound that can be polymerized by having an α, β-ethylenically unsaturated group represented by the following chemical formula (1) (hereinafter simply referred to as “ethylenic compound”). ). This ethylenic compound may be a monofunctional compound having only one α, β-unsaturated ethylene group, or may be a polyfunctional compound having two or more such groups.

但し、式（１）中のＲ_１〜Ｒ_４は、各々有機基、水素原子、重水素原子又はハロゲン原子を表す。

However, R < ₁ > -R < ₄ > in Formula (1) represents an organic group, a hydrogen atom, a deuterium atom, or a halogen atom, respectively.

Examples of the α, β-unsaturated ethylene group include an acryloyl group and a methacryloyl group. Furthermore, a deuterated acryloyl group and a deuterated methacryloyl group in which some or all of the hydrogen atoms constituting these groups are substituted with deuterium atoms are exemplified. In addition, a halogenated acryloyl group and a halogenated methacryloyl group in which a part or all of the hydrogen atoms constituting these groups are substituted with a halogen atom are exemplified. When the ethylenic compound is a polyfunctional compound, these groups may include only one type or two or more types.
Examples of the ethylenic compound having an α, β-unsaturated ethylene group include acrylic acid ester (for example, obtained by esterifying an alcoholic hydroxyl group with acrylic acid), and methacrylic acid ester (for example, alcoholic hydroxyl group is methacrylate). And a derivative thereof, which can be obtained by esterification with an acid).

The “radical generator” is one of the above-described polymerization initiators, and is caused by irradiation of near infrared light to a compound that can generate radicals by irradiation of near infrared light, and / or a near infrared photosensitizer. A compound that can generate radicals. This radical generator may use only 1 type and may use 2 or more types together.
The radical generator is not particularly limited, and examples thereof include organic boron complexes, carbonyl compounds, organic peroxides, azo compounds, s-triazine compounds, hexaarylbiimidazole compounds, and titanocene compounds. Of these, organoboron complexes, carbonyl compounds, and organic peroxides are particularly preferable.

但し、式（２）中のＲ_５〜Ｒ_８は、各々アルキル基、アルケニル基、アルキニル基、アリール基、脂環式基及び複素環基である。また、各基は各々置換基を有してもよく、有さなくてもよい。更に、Ｒ_５〜Ｒ_８は互いに連結して環状構造であってもよく、連結していなくてもよい。一方、Ｌ^＋は、対カチオンである。 Among these, examples of the organic boron-based complex include compounds represented by the following general formula.

However, R < ₅ > -R < ₈ > in Formula (2) is an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alicyclic group, and a heterocyclic group, respectively. In addition, each group may or may not have a substituent. Further, R _{5 to} R ₈ may be linked to each other to have a cyclic structure, or may not be linked. On the other hand, L ⁺ is a counter cation.

Examples of the substituent that R _{5 to} R ₈ can have include an alkyl group, an alkoxy group, an acyloxy group, a carboxyl group, an alkoxycarbonyl group, a hydroxyl group, an amino group, a deuterium atom, and a halogen atom. Each of the groups that can be R _{5 to} R ₈ is preferably an alkyl group having 1 to 10 carbon atoms. The alkenyl group, alkynyl group and alicyclic group preferably have 3 to 20 carbon atoms. The aryl group and heterocyclic group preferably have 6 to 30 carbon atoms.
Further, it is preferable that three of R _{5 to} R ₈ are aryl groups and the remaining one is an alkyl group. These aryl groups and alkyl groups may or may not have each of the above substituents.

  That is, as the organic boron anion, for example, butyl triphenyl boron anion, butyl tris (methylphenyl) boron anion, butyl tris (trimethylphenyl) boron anion, butyl tris (methoxyphenyl) boron anion, butyl tris (chlorophenyl) boron anion, butyl tris (dichlorophenyl) ) Boron anion, butyl tris (trichlorophenyl) boron anion, butyl tris (fluorophenyl) boron anion, butyl tris (difluorophenyl) boron anion, butyl tris (trifluorophenyl) boron anion, butyl tris (fluoromethylphenyl) boron anion, and butyl tris ( And difluoropyrrolylphenyl) boron anion.

The L ⁺ is not particularly limited as long as it can be a counter cation with respect to the organoboron anion, but is not limited to ammonium cation, phosphonium cation, oxonium cation, sulfonium cation, arsonium cation, stibonium cation, selenium cation. , Onium compounds such as stannonium cations and iodonium cations, and transition metal coordination cations. Among these, an ammonium cation is preferable, and a tetraalkylammonium cation is particularly preferable. The alkyl group in the tetraalkylammonium cation preferably has 1 to 10 carbon atoms.

Furthermore, as said L ^<+ >, the cationic compound which has an absorption maximum in the range of 700-2500 nm is mentioned. That is, for example, a cationic compound having a structure in which heteroatoms (N, O, S, etc.) are bonded by a polymethine chain can be used. Furthermore, it is preferable that the hetero atom bonded by the polymethine chain is a cationic compound constituting a heterocyclic structure.
This heterocyclic structure includes benzopyrrole, benzofuran, benzothiophene, benzopyrazole, benzothiazole, benzoxazole, naphthopyrrole, naphthofuran, naphthothiophene, naphthopyrazole, naphthothiazole, naphthoxazole, quinoline, chromene, benzothiopyran, benzoquinoline, Examples thereof include benzochromene and naphthothiopyran. Furthermore, those in which part or all of the hydrogen atoms of these heterocyclic structures are substituted with deuterium atoms and / or halogen atoms are exemplified.
That is, for example, polymethine dyes, merocyanine dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, anthraquinone dyes, naphtholactam dyes, pencetane dyes, oxyindolizine dyes, quinoid dyes and indoaniline dyes And pigments. These may use only 1 type and may use 2 or more types together. In addition, when these compounds have a central metal, the kind of the central metal is not particularly limited.

Examples of the carbonyl compound include benzophenone derivatives such as benzophenone and 2-methylbenzophenone, acetophenone derivatives, thioxanthone derivatives (2,4-diethylthioxanthone, 2-chlorothioxanthone, etc.), benzoic acid ester derivatives (p-dimethylaminobenzoic acid). Ethyl and the like), [4- (methylphenylthio) phenyl] phenylmethanone, and ethylanthraquinone.
Furthermore, examples of the organic peroxide include methyl ethyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, and peroxide-metal alkyl.

(1-2) Epoxy composition The epoxy composition is a kind of near-infrared curable composition, and is a composition containing an epoxy polymerizable compound and an acid generator.
Among these, the epoxy-based polymerizable compound refers to a compound that can be polymerized by having an epoxy group (hereinafter simply referred to as “epoxy compound”). The kind of this epoxy compound is not specifically limited. That is, for example, it may be an oligomer, a monomer, or a mixture thereof. The monomer (in the oligomer, the monomer before oligomerization) and the oligomer may be bifunctional, polyfunctional, or a mixture thereof. Furthermore, as these monomers and oligomers, deuterates in which some or all of the hydrogen atoms are substituted with deuterium atoms can be used. In addition, a halide in which some or all of the hydrogen atoms are substituted with halogen atoms can be used. Furthermore, it may or may not have a silicone chain in the molecule.

Examples of the bifunctional epoxy compound include glycidyl ether type, glycidyl amine type, glycidyl ester type, and alicyclic type (such as an epoxy compound having a cyclohexene oxide structure). Among these, examples of the glycidyl ether type include various bisphenol types, biphenyl types, naphthalene types, and fluorene types. Among these, examples of the bisphenol type include bisphenol A type, bisphenol F type, hydrogenated bisphenol type, bisphenol AF type, and bisphenol S type. Examples of the glycidylamine type include hydantoin type, aniline type, and toluidine type.
On the other hand, examples of the polyfunctional epoxy compound include glycidyl ether type and glycidyl amine type. Among these, examples of the glycidyl ether type include a phenol novolak type, a cresol novolak type, a diphenylpropane type, a trishydroxyphenylmethane type, and a tetraphenylolethane type. Examples of the glycidylamine type include aminophenol type, tetraglycidyldiaminidiphenylmethane type, triglycidyl isocyanurate type, and 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane type.
These glycidyl ether type epoxy compounds include monovalent aliphatic alcohols, polyhydric aliphatic alcohols, monovalent aromatic alcohols and polyvalent aromatic alcohols, glycidyl ether types derived from monohydric phenols and polyhydric phenols. Epoxy compounds are included. Examples of the aromatic ring constituting each aromatic alcohol include a benzene ring, a naphthalene ring, and an anthracene ring.
A compound in which some or all of the hydrogen atoms of each of these epoxy compounds are substituted with deuterium atoms and / or halogen atoms is exemplified.

The acid generator is one of the above-described polymerization initiators, and generates an acid with near-infrared irradiation and / or near-infrared irradiation to the above-mentioned near-infrared photosensitizer. Refers to a compound that can. Examples of the acid generator include ionic acid generators and nonionic acid generators. Examples of ionic acid generators include Lewis acid generators (various diazonium salts such as aryldiazonium salts), Bronsted acid generators {various onium salts (iodonium salts such as diaryliodonium salts, sulfonium salts such as diarylsulfonium salts, diaryls) Selenonium salts such as selenonium salts, sulfonium salts such as dialkylphenacylsulfonium salts, etc.)}. Examples of nonionic acid generators include sulfonic acid generators (such as sulfonic acid esters), carboxylic acid generators (such as carboxylic acid esters), and amide derivatives. These acid generators may be used alone or in combination of two or more.
Furthermore, the near infrared sensitizer can be contained in this epoxy-type composition similarly to the ethylene-type composition in said (1-1).

(1-3) Ethylene epoxy-based composition The ethylene epoxy-based composition is a kind of near-infrared curable composition, an α, β-unsaturated ethylene group epoxy group-containing polymerizable compound, a radical generator, And an acid generator.
Among these, the α, β-unsaturated ethylene group epoxy group-containing polymerizable compound includes both the α, β-ethylenically unsaturated group in the above (1-1) and the epoxy group in the above (1-2). Examples thereof include the above-mentioned ethylenic compounds having an epoxy group and the above-described epoxy compounds having an α, β-unsaturated ethylene group. These may use only 1 type and may use 2 or more types together. That is, for example, a compound obtained by adding a carboxylic acid (such as acrylic acid or methacrylic acid) having an α, β-ethylenically unsaturated group to a part or all of the epoxy groups of the epoxy oligomer (for example, epoxy acrylate) Is mentioned.
Moreover, about a radical generator and an acid generator, each in the said ethylene-type composition and the said epoxy-type composition is applicable as it is.

Each of the ethylene-based composition, the epoxy-based composition and the ethylene-epoxy-based composition described in (1-1) to (1-3) above contains a near-infrared sensitizer regardless of other components. be able to. The near-infrared photosensitizer has a sensitizing action on near-infrared rays and can assist the polymerization initiator. This near-infrared sensitizer is effective when it is difficult to obtain sufficient near-infrared photosensitivity with only a polymerization initiator or a polymerization initiating group.
Examples of the near-infrared sensitizer include an infrared-absorbing dye having an absorption maximum in the range of 700 to 2500 nm. That is, for example, a near-infrared sensitizer having a structure in which heteroatoms (N, O, S, etc.) are bonded by a polymethine chain can be used. Furthermore, it is preferable that the hetero atom bonded by the polymethine chain is a near-infrared sensitizer that constitutes a heterocyclic structure.
This heterocyclic structure includes benzopyrrole, benzofuran, benzothiophene, benzopyrazole, benzothiazole, benzoxazole, naphthopyrrole, naphthofuran, naphthothiophene, naphthopyrazole, naphthothiazole, naphthoxazole, quinoline, chromene, benzothiopyran, benzoquinoline, Examples thereof include benzochromene and naphthothiopyran. Furthermore, those in which part or all of the hydrogen atoms of these heterocyclic structures are substituted with deuterium atoms and / or halogen atoms are exemplified.
That is, for example, polymethine dyes, merocyanine dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, anthraquinone dyes, naphtholactam dyes, pencetane dyes, oxyindolizine dyes, quinoid dyes and indoaniline dyes And pigments. These may use only 1 type and may use 2 or more types together. In addition, when these compounds have a central metal, the kind of the central metal is not particularly limited.
As these near infrared sensitizers, those which are decomposed as the photocuring reaction proceeds can be used. For this reason, near-infrared rays are gradually transmitted with curing, and the near-infrared rays have sufficient transparency after curing.

Furthermore, in each of the ethylene-based composition, the epoxy-based composition, and the ethylene-epoxy-based composition described in (1-1) to (1-3), after curing with near infrared rays regardless of other components, A thermal polymerization initiator can be included for the final thermosetting. The kind etc. of thermal polymerization initiator are not specifically limited. Various thermal radical generators can be used for the ethylene-based composition and the ethylene-epoxy-based composition. That is, for example, various organic peroxides (benzoyl peroxide, etc.) can be mentioned. On the other hand, for epoxy-based compositions and ethylene-epoxy-based compositions, aromatic sulfonium salt compounds (for example, SbF ₆ ^- and PF ₆ ^- etc. as counter anions), thiophene compound salts (for counter anions) , for example, SbF ₆ ^- and PF ₆ ^-, etc.), pyridine compound, a soluble organic acid (e.g., trifluoroacetic acid and p-toluenesulfonic acid, etc.), and a Lewis acid (e.g., boron trifluoride monoethylamine trifluoride Boron benzylamine, tetrafluoroborate, etc.). Specifically, SI-100L, SI-80L, SI-60L, SI-110L and SI-180L manufactured by Sanshin Chemical Co., Ltd., Adeka Opton CP-66 and CP-77 manufactured by Asahi Denka Co., Ltd., Nippon Soda CI-2639 and CI-2624 manufactured by Corporation, BSP (2-tribromomethylsulfonylpyridine), BMPS (α, α, α-tribromomethylphenylsulfone) manufactured by Sumitomo Seika Co., Ltd. and the like can be mentioned.
Although content of these thermal polymerization initiators is not specifically limited, For example, it is 0.1-30 mass% (preferably 0.5-20 mass%, More preferably, it is 1-20 mass% with respect to the whole near-infrared curable composition. 10 mass%, particularly preferably 1 to 5 mass%).

<2> Manufacturing method of device with optical waveguide structure The manufacturing method of a device with an optical waveguide structure of the present invention comprises a core portion made of a cured near-infrared curable resin and propagating light, and a cladding portion surrounding the core portion. An uncured layer forming step for forming an uncured layer comprising a near-infrared curable composition that is cured to become a near-infrared curable resin, and a method for producing a device with an optical waveguide structure including the optical waveguide structure And a core part forming step of forming a core part by irradiating with near infrared rays.

The “uncured layer forming step” is a step of forming an uncured layer made of a near-infrared curable composition that is cured to become a near-infrared curable resin.
The “uncured layer” is a layer made of a near-infrared curable composition. Although the formation site of this uncured layer is not particularly limited, for example, when it has a base part as described above, it can be formed on the surface of the part to be the base part. Further, the planar shape of this layer is not particularly limited. Further, the thickness is not particularly limited, but is usually 300 μm or less.
This uncured layer is an uncured layer and represents that polymerization has not been completed. That is, the uncured layer may be solid or liquid. Also, the presence or absence of viscosity is not particularly limited.
The method for forming the uncured layer is not particularly limited. For example, it can be directly formed at the formation position using various printing methods such as a doctor blade method, a spin coating method, a spray method, a curtain coating method, and a roll coating method. In addition, the uncured layer releasably held on the base layer (release sheet or the like) can be transferred to a desired position and indirectly formed.

The “core portion forming step” is a step of forming the core portion by irradiating the uncured layer with near infrared rays. The formation method of the core part in this core part formation process is not specifically limited, What is necessary is just to use the near infrared rays which can harden | cure a near-infrared hardening composition. That is, for example, the following methods (1) to (3) are exemplified. That is,
(1) After the uncured layer forming step and before the core portion forming step, a light emitting element disposing step of disposing a light emitting element emitting near infrared rays on the uncured layer is provided. A method of irradiating infrared rays using the light emitting element and selectively curing a portion of the uncured layer irradiated and transmitted with near infrared rays to form a core part (hereinafter, also simply referred to as “self-forming method”),
(2) A method of forming a core part by applying a photolithography method using near infrared rays to an uncured layer (hereinafter, also simply referred to as “photolitho method”),
(3) A method of drawing and forming a core portion by irradiating a near infrared laser (hereinafter, also simply referred to as “laser drawing method”).

(1) Self-forming method In the self-forming method, the “light emitting element disposing step” includes arranging a light emitting element emitting near infrared rays on the uncured layer after the uncured layer forming step and before the core portion forming step. It is a process to install. The light emitting element is not particularly limited, and the light emitting element in the device with an optical waveguide structure of the present invention can be applied as it is. In particular, this self-forming method can improve the position accuracy of the optical waveguide structure by accurately determining the position of the light emitting element, and can reduce transmission loss. Further, unlike a conventional method using an ultraviolet light emitting element, a near infrared light emitting element that can be used for communication is used, so that the number of times of positioning can be reduced and the position accuracy can be improved.

In order to more accurately perform the mounting position of the light emitting element, it is preferable to use a positioning reference. The positioning reference is not particularly limited, and a part of the device with the optical waveguide structure may be used, or another part other than the device with the optical waveguide structure may be used (holding the device with the optical waveguide structure) Part of the jig). When using a part of a device with an optical waveguide structure, a positioning reference part that functions only as a positioning reference may be provided, and it is already included as a part of a device with an optical waveguide structure ( An optical path conversion unit and a part of a conductor such as a land, a via conductor, and a through-hole conductor) may be used.
The method of using these positioning references is not particularly limited. For example, a region including the positioning references is imaged using an imaging means (camera, etc.), and light emitting elements are arranged based on the obtained image or the result of analyzing this image. The method of doing is mentioned. Further, an automatic focus maintaining method can be used by using near infrared rays used for forming the core portion. The positioning reference can be used not only for the arrangement of the light emitting elements but also for various purposes such as mounting of other optical elements and electronic components, formation of conductor portions, and the like.

  Further, in addition to the light emitting element arranging step, a step of arranging other portions can be provided before the core portion forming step. Examples of the other part include the other part described in the device with an optical waveguide structure of the present invention and the positioning reference part. Especially, the light receiving element arrangement | positioning process which arrange | positions the light receiving element which light-receives the near infrared rays emitted from the light emitting element can be provided. By disposing the light receiving element before the core portion forming step, the positioning accuracy can be further improved, so that the transmission loss in the obtained device with an optical waveguide structure can be effectively reduced. Moreover, an optical path conversion unit can be provided. By having the optical path changing portion, the core portion having the bent portion can be formed easily and accurately in the core portion forming step.

  On the other hand, in the “core part forming step”, near infrared rays are emitted from the light emitting element arranged in the previous step, and this near infrared ray is irradiated to a desired portion of the uncured layer, and the near infrared ray of the uncured layer is irradiated. And a step of selectively curing the transmitted site.

(2) Photolithographic method The photolithographic method is a method in which a desired core portion pattern is exposed to an uncured layer using near infrared rays to cure a desired portion of the near infrared curable composition, and then the near infrared rays are not irradiated. A method including a step of removing a portion that remains uncured. At the time of exposure, a contact exposure method in which exposure is performed by bringing the mask into close contact with the uncured layer may be used, or a projection exposure method in which exposure is performed without bringing the mask into contact with the uncured layer may be used.

(3) Laser drawing method The laser drawing method is a method in which a laser source that emits near infrared rays is moved with respect to an uncured layer, and the refractive index of the path irradiated with laser light is increased from the other parts to It is a method to do. At this time, the laser beam may be irradiated without being condensed, or may be condensed and irradiated. That is, for example, when used without condensing, the portion irradiated or transmitted with laser light from the surface of the uncured layer can be cured. On the other hand, when condensed and used, only the vicinity of the focal point of the laser light in the uncured layer can be cured. Further, when the laser transmission source is moved relative to the uncured layer, the laser transmission source may be moved, the uncured layer may be moved, or both of them may be moved relatively.

Hereinafter, the present invention will be specifically described with reference to examples and drawings.
[1] Device with Optical Waveguide Structure FIG. 1 is a diagram schematically showing a cross section of an example of a device with an optical waveguide structure according to the present invention. The device with an optical waveguide structure 100 includes an optical waveguide structure 10, a multilayer ceramic wiring board 20, optical elements 31 and 32, optical path conversion parts 41 and 42, conductor parts 51 and 52, and the like.

  The optical waveguide structure 10 includes a core part 11 and a clad part 12. The core portion 11 includes bent portions 111 and 112 whose optical paths are changed by the optical path changing portions 41 and 42. Moreover, the core part 11 consists of near-infrared curable resin, and is formed by the self-forming method mentioned later. On the other hand, the clad portion 12 is made of an acrylic resin that differs from the core portion 11 only in the degree of polymerization.

  The multilayer ceramic wiring board 20 has a conductor portion (via pattern and via hole for interlayer connection, etc.) and an alumina-based sintered material inside thereof, and these conductor portions are made of an alumina-based sintered material. Insulated. The optical waveguide structure 10 is provided on one side of the multilayer ceramic substrate 20, and a plurality of connection terminals 52 are provided on the other side. This device with an optical waveguide structure can be mounted on a printed wiring or the like (not shown) using the connection terminal 52.

As optical elements, a VCSEL that is a light emitting element 31 and a photodiode that is a light receiving element 32 are provided. The light emitting element 31 can emit near infrared rays, and the light receiving element 32 can detect the near infrared rays. The light emitting element 31 includes a light emitting portion, and is mounted with the light emitting portion facing downward. On the other hand, the light receiving element 32 includes a light receiving portion and is mounted with the light receiving portion facing downward. Each optical element is bonded via a conductor portion 51 formed on the surface of the cladding portion 12.
Each of these optical elements receives an electrical signal from an external circuit (not shown) and is converted into an optical signal by the light emitting element 31, and near infrared rays emitted from the light emitting element 31 as an optical signal are transmitted through the core portion 11 and received. Light is received by the element 32. The optical signal received by the light receiving element 32 is converted into an electric signal by the light receiving element 32 and transmitted to an external circuit (not shown).

Further, as the light conversion unit, there are provided quadrangular pyramid shaped optical path conversion units 41 and 42 made of gold and having inclined surfaces of about 45 ° facing each other. These optical path conversion units 41 and 42 are mounted on one surface of the multilayer ceramic wiring board 20.
Furthermore, as a conductor portion, there are a conductor portion 51 for connecting the light emitting element 31 and the light receiving element 32 to an electric circuit (not shown), and a connection terminal for mounting a device with an optical waveguide structure on a printed wiring board (not shown). And a conductor portion 52. These conductor portions 51 and 52 are made of copper and silver wiring.

[2] Manufacturing method of device with optical waveguide structure (self-forming method)
A method for manufacturing an example of the device with an optical waveguide structure of the present invention described in [1] will be described below. In the following description of the manufacturing method, for the sake of convenience, each part will be described using the reference numerals of the device with the optical waveguide structure after manufacturing.
(1) Multilayer ceramic wiring board 20
A pre-sintered multilayer ceramic wiring board 20 was prepared. The configuration of the multilayer ceramic wiring board is as described in [1] above.

(2) Formation of optical path conversion part pads 71 and 72 and positioning reference pad 61 On one surface of the multilayer ceramic wiring board 20, a portion where no pad is formed is protected with a dry film, which is a plating resist, and then gold plating is applied. Then, the dry film was peeled off to form the optical path conversion part pads 71 and 72 and the positioning reference pad 61 (see step 1 in FIG. 2).

(3) Formation of optical path conversion parts 41 and 42 A gold wire is supplied into the capillary provided in the wire bonding apparatus, and the tip part of this gold wire is made into a lump. Thereafter, the capillary was pressed against the optical path conversion portion pad 71 and simultaneously pressed by the tip of the capillary to form a quadrangular pyramid-shaped optical path conversion portion 41. Similarly, a quadrangular pyramid-shaped optical path conversion section 42 having an inclined surface of approximately 45 ° facing the optical path conversion section 41 was formed on the optical path conversion section pad 72. Note that when forming the optical path conversion units 41 and 42, they were accurately formed at desired positions based on the coordinates of the positioning reference 61 using image means (see step 2 in FIG. 2). In addition, after pressing a metal lump, this metal lump may be shape | molded into a predetermined shape using a stamping jig.

(4) Formation of near-infrared curable composition layer 13 An epoxy acrylate which is an α, β-unsaturated ethylene group-containing polymerizable compound was prepared as follows. That is, from 206 parts by mass of cresol novolac type epoxy resin having an epoxy equivalent of 206 (product name “Epototo YDCN704” manufactured by Toto Kasei Co., Ltd.), 72 parts by mass of acrylic acid, 0.2 parts by mass of tetraethylammonium chloride and 0.5 parts by mass of methyl hydroquinone. The resulting mixture was added to 192 parts by mass of diethylene glycol ethyl ether acetate and reacted at 100 ° C. for 10 hours to obtain an epoxy acrylate.
Thereafter, 90 parts by mass of the obtained epoxy acrylate, 10 parts by mass of trimethylolpropane acrylate (manufactured by Nippon Kayaku Co., Ltd., product name “KS-TMPTA”), 5 parts by mass of benzophenone as a photo radical generator, and a near infrared sensitizer A near-infrared curable composition was obtained by mixing 2 parts by weight of a cationic dye (absorption wavelength 822 nm) represented by the following chemical formula (3) and 5 parts by weight of benzoyl peroxide as a thermal radical generator.
Next, the obtained near-infrared curable composition was formed into a film having a thickness of 150 μm that was releasably held on a release sheet, and a film to be a near-infrared curable composition layer was prepared.

但し、式（３）中の「Ｐｈ」はフェニル基を表す。

However, “Ph” in the formula (3) represents a phenyl group.

  The obtained film was affixed so as to cover the surface of the multilayer ceramic wiring board and pressure-bonded, and the release sheet was removed. Then, it dried at 80 degreeC for 1 hour, and formed the near-infrared curable composition layer 13 (refer the process 3 in FIG. 2). At this stage, the near-infrared curable composition layer 13 has substantially no fluidity, and the following steps (wiring transfer, etc.) can be performed. This is probably because the curing reaction has already started at this point, and a three-dimensional crosslinked structure has begun to be formed.

(5) Formation of conductor part 51 and positioning reference pad 62 On the surface of near infrared curable composition layer 13 formed in (4) above, a thin film made of copper that becomes conductor part 51 and positioning reference pad 62 is a release sheet. A transfer film that was releasably held on the surface was prepared. Thereafter, the transfer film was transferred to the surface of the near-infrared curable composition 10 at the position determined based on the positioning reference 61 using the image means in the same manner as described above, and the conductor portion 51 and the positioning reference pad 62 were formed. (See step 4 in FIG. 2).

(6) Mounting of the light emitting element 31 and the light receiving element 32 (light emitting element arranging step)
Similarly to the above, based on the positioning reference 62 using the image means, the light emitting element 31 is accurately placed on the conductive portion 51 at a target position, and the conductor portion is formed by solder provided on one surface of the light emitting element 31 in advance. 51. Similarly, based on the positioning reference 62, the light receiving element 32 was mounted and similarly connected by soldering (see step 5 in FIG. 3).

(7) Self-formation of the core part 11 (core part formation process)
Near-infrared light was emitted from the light emitting element 31, and the near-infrared radiation of the near-infrared curable composition layer 13 and the transmitted portion were cured. The portion cured by the near infrared ray emitted from the light emitting element 31 is gradually extended (see step 6 in FIG. 3), extends to the optical path conversion unit 41, and is optically converted by the optical path conversion unit 41 by approximately 90 °. The optical path was changed again by the optical path changing section 42 and reached just below the light receiving element 32. Curing was stopped after confirming that the amount of near infrared rays predicted in advance reached the light receiving element 32 (see step 7 in FIG. 3).

(8) Heat-curing of optical waveguide structure 10 The structure obtained up to (7) above was placed in a thermostatic bath at a temperature of 150 ° C. and heated for 1 hour to advance the curing of the entire optical waveguide structure 10. . Then, a refractive index difference is formed by a difference in polymerization degree between a portion to be the core portion 11 previously cured by near infrared rays and a portion to be the cladding portion 12 cured by benzoyl peroxide which is a thermal radical generator, Part 11 and clad part 12 were completed. The refractive index difference between the obtained core part 11 and the clad part 12 was 0.3%. Thus, the device 100 with an optical waveguide structure of the present invention was obtained (see step 8 in FIG. 3).

[3] Manufacturing method of device with optical waveguide structure (photolithographic method)
The manufacturing method of the other example of the device with an optical waveguide structure of the present invention will be described below. In the following description of the manufacturing method, for the sake of convenience, each part will be described using the reference numerals of the device with the optical waveguide structure after manufacturing.
(1) Formation of multilayer ceramic wiring board 20 and optical path changing part etc. A multilayer ceramic wiring board 20 sintered in advance was prepared. The configuration of the multilayer ceramic wiring board is the same as [1] above.
Thereafter, in the same manner as in the above [2] (2), the optical path conversion unit pads 71 and 72 and the positioning reference pad 61 were formed (see step 1 in FIG. 4). Thereafter, in the same manner as in the above [2] (3), the optical path conversion units 41 and 42 were formed (see step 2 in FIG. 4).

(2) Formation of the lower clad part 12 The epoxy acrylate used in (4) of the above [2] was prepared as the α, β-unsaturated ethylene group-containing polymerizable compound. 70 parts by mass of this epoxy acrylate, 30 parts by mass of trimethylolpropane acrylate (manufactured by Nippon Kayaku Co., Ltd., product name “KS-TMPTA”), 5 parts by mass of benzophenone which is a photoradical generator, and the above chemical formula which is a near infrared sensitizer A near-infrared curable composition was obtained by mixing with 2 parts by mass of the cationic dye (absorption wavelength 822 nm) represented by (3) and 5 parts by mass of benzoyl peroxide as a thermal radical generator.
The obtained near-infrared curable composition was coated on the multilayer ceramic wiring substrate 20 by a spin coat method. Next, exposure (exposure amount: 1000 mJ / cm ² , light source: xenon short arc lamp, exposure time: about 10 minutes) was performed and cured to form the lower clad portion 12 (see step 9 in FIG. 4).

(3) Formation of the core part 11 (core part formation process)
On the lower clad part 12 formed in the above (2), the near-infrared curable composition obtained in the above (2) was applied by a spin coating method. Next, exposure (exposure amount: 1000 mJ / cm ² , light source: xenon short arc lamp, exposure time: about 10 minutes) was performed and cured. Thereafter, development was performed using 2-methoxyethanol (30 seconds × twice), and washing with isopropyl alcohol (IPA) was performed to form the core portion 11 (see step 10 in FIG. 4).

(4) Formation of upper clad part 12 'On the core part 11 formed by said (3), the near-infrared curable composition obtained by said (2) was apply | coated by the spin coat method. Next, exposure (exposure amount: 1000 mJ / cm ² , light source: xenon short arc lamp, exposure time: about 10 minutes) was performed and cured to form an upper clad portion 12 ′ (see step 11 in FIG. 5).

(5) Formation of conductor part 51 and positioning reference pad 62 A thin film made of copper that becomes conductor part 51 and positioning reference pad 62 is formed on the surface of the release sheet on the surface of upper clad part 12 'formed in (4) above. A transfer film held in a peelable manner was prepared. Thereafter, the transfer film was transferred to the surface of the upper clad portion 12 ′ at the position determined based on the positioning reference 61 using the image means in the same manner as described above, and the conductor portion 51 and the positioning reference pad 62 were formed ( (See step 12 in FIG. 5).
The conductor 51 and the positioning reference pad 62 can be formed by plating in the same manner as [2] (2).

(6) Mounting of the light emitting element 31 and the light receiving element 32 (light emitting element arranging step)
Similarly to the above, based on the positioning reference 62 using the image means, the light emitting element 31 is accurately placed on the conductive portion 51 at a target position, and the conductor portion is formed by solder provided on one surface of the light emitting element 31 in advance. 51. Similarly, based on the positioning reference 62, the light receiving element 32 was mounted and similarly connected by soldering (see step 13 in FIG. 5). Thus, a device 100 ′ with an optical waveguide structure of the present invention was obtained. The difference in refractive index between the obtained core portion 11 and the clad portions 12 and 12 ′ was 1.2%.

  The device with an optical waveguide structure and the manufacturing method thereof according to the present invention can be widely used in the fields of optical communication, electric and electronics, and the like. For example, it can be used as an optical waveguide, an optical branching coupler, an optical multiplexer / demultiplexer, an optical isolator, an optical fiber amplifier, a wiring board, and the like.

It is typical sectional drawing of an example of the device with an optical waveguide structure of this invention. It is explanatory drawing typically demonstrated of the manufacturing method of an example of the device with an optical waveguide structure of this invention. It is explanatory drawing which illustrates typically the process following FIG. 2 of the manufacturing method of an example of the device with an optical waveguide structure of this invention. It is explanatory drawing typically demonstrated of the manufacturing method of the other example of the device with an optical waveguide structure of this invention. It is explanatory drawing which illustrates typically the process of following FIG. 4 of the manufacturing method of the other example of the device with an optical waveguide structure of this invention. It is explanatory drawing explaining an example of the cross section of a core part and a clad part. It is explanatory drawing explaining the other example of the cross section of a core part and a clad part. It is explanatory drawing explaining an optical path conversion part.

Explanation of symbols

  100 and 100 '; device with optical waveguide structure, 10; optical waveguide structure, 11; core portion, 111 and 112; bent portion, 12 and 12'; clad portion, 13; near infrared curable composition layer, 20; Wiring board, 31; light emitting element, 32; light receiving element, 41 to 45; optical path conversion unit, 51 and 52; conductor part, 61 and 62; positioning reference, 71 and 72;

Claims (10)

  A device with an optical waveguide structure comprising an optical waveguide structure made of a cured near-infrared curable resin and having a core portion through which light propagates and a cladding portion surrounding the core portion.   A device with an optical waveguide structure, comprising: an optical waveguide structure having a core portion that is cured by near infrared rays and propagates light; and a cladding portion that surrounds the core portion.   3. The optical waveguide structure according to claim 1, further comprising a light emitting element that emits near infrared light on at least one end side of the core part, wherein the core part is cured by near infrared light emitted from the light emitting element. Device.   4. The device with an optical waveguide structure according to claim 1, further comprising an optical path conversion unit that reflects the light propagating in the core unit, wherein the core unit is bent at the optical path conversion unit. 5.   The device with an optical waveguide structure according to claim 1, wherein the core part and the clad part are made of the same kind of resin.   The device with an optical waveguide structure according to claim 1, wherein the core portion includes an acrylic resin.   The device with an optical waveguide structure according to claim 1, wherein the core portion includes an epoxy resin. A manufacturing method of a device with an optical waveguide structure comprising an optical waveguide structure having a core portion made of a cured near-infrared curable resin and having light propagated, and a cladding portion surrounding the core portion,
An uncured layer forming step of forming an uncured layer comprising a near-infrared curable composition which is cured to become a near-infrared curable resin;
A core part forming step of forming the core part by irradiating the uncured layer with near-infrared rays. A method for manufacturing a device with an optical waveguide structure according to claim 8,
After the uncured layer forming step and before the core portion forming step, a light emitting element disposing step of disposing a light emitting element emitting near infrared rays on the uncured layer is provided.
In the core part forming step, an optical waveguide that irradiates the near infrared ray using the light emitting element and selectively cures a portion of the uncured layer irradiated and transmitted with the near infrared ray to form the core part. A method for manufacturing a structured device. A method for manufacturing a device with an optical waveguide structure according to claim 8,
In the core part forming step, a method of manufacturing a device with an optical waveguide structure, wherein the core part is formed by performing a photolithography method using the near infrared ray on the uncured layer.

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