JP2017167455A - Optical waveguide, method of manufacturing the same, method of manufacturing optical waveguide assembly, and method of manufacturing optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical waveguide that facilitates optical axis alignment with an optical member as a separate body such as a photoelectric conversion element and an optical fiber connector and has excellent optical signal propagation efficiency, and to provide a method of manufacturing the same, a method of manufacturing an optical waveguide assembly, and a method of manufacturing an optical module.SOLUTION: A plate-shaped optical waveguide includes: a core pattern 1 for optical signal transmission; a cladding layer 2 that embeds the core pattern 1 for optical signal transmission; an optical path conversion mirror 3 that is provided on the core pattern 1 for optical signal transmission; and an inclined surface 4 between a position of which and the optical path conversion mirror 3 correlation is secured. The optical waveguide is provided in which the inclined surface 4 is an alignment surface 11 with a housing 6 on the outside. A method of manufacturing an optical waveguide assembly made by bringing at least the alignment surface 11 of the optical waveguide into alignment with the housing 6 on the outside is also provided.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an optical waveguide, a manufacturing method thereof, a manufacturing method of an optical waveguide assembly, and a manufacturing method of an optical module.

  In IC technology and LSI technology, in order to improve operation speed and integration, a part of the electrical wiring on the electrical wiring board is replaced with optical wiring such as an optical fiber or an optical waveguide, and an optical signal is used instead of an electrical signal. Things have been done. When optical signals are used for short-distance signal transmission between boards and within boards, it is desirable to use optical waveguides that have higher wiring flexibility and higher density than optical fibers. Optical waveguides using polymer materials with excellent properties are promising.

  When optically connecting an optical waveguide to a photoelectric conversion element or a motherboard, there is a merit that the storage size can be reduced. Therefore, a method of providing an optical path conversion function using a mirror is often used for the optical waveguide. In addition, in order to perform optical communication between the photoelectric conversion element or the mother board and the optical waveguide, it is necessary to arrange each with high positional accuracy. Therefore, there is a method such as alignment using pins as in Patent Document 1. .

JP 2013-195462 A

  However, as in Patent Document 1, it is necessary to form the positional relationship between the outer shape and the optical path in the waveguide with high accuracy in the abutment method or the guide pin method.

  The present invention has been made to solve the above problems, and is easy to align the optical axis with a separate optical member such as a photoelectric conversion element or an optical fiber connector, and has an excellent optical signal propagation efficiency, An object of the present invention is to provide a manufacturing method thereof, a manufacturing method of an optical waveguide assembly, and a manufacturing method of an optical module.

As a result of diligent research to solve the above problems, the present inventors have found that an optical signal transmission core pattern, a cladding layer and an optical path conversion mirror in which the optical signal transmission core pattern is embedded, and the optical path conversion mirror and position It has been found that the above-mentioned problems can be solved by using the inclined optical surface as an alignment surface A with an external housing. The present invention has been completed based on such knowledge.
That is, the present invention relates to the following.
(1) An optical signal transmission core pattern, a cladding layer in which the optical signal transmission core pattern is embedded, an optical path conversion mirror provided in the optical signal transmission core pattern, and a correlation between positions of the optical path conversion mirror and An optical waveguide having a secured inclined surface, wherein the inclined surface is an alignment surface A with an external housing.
(2) The optical waveguide according to (1), wherein the optical path conversion mirror and the inclined surface are on the same plane or a parallel plane.
(3) The optical waveguide according to (1) or (2), wherein one surface of the optical waveguide that forms an acute angle with the inclined surface is an alignment surface B with the external casing.
(4) Two surfaces C or D that intersect with the inclined surface and form two side surfaces of the optical waveguide parallel to the longitudinal direction of the optical signal transmission core pattern are alignment surfaces C with the external casing. Or the optical waveguide as described in any one of (1)-(3) which is the alignment surface D.
(5) The method of manufacturing an optical waveguide according to any one of (1) to (4),
A method for manufacturing an optical waveguide, wherein the alignment surface C or the alignment surface D to be a guide core pattern is formed simultaneously with the optical signal transmission core pattern.
(6) A method of manufacturing an optical waveguide assembly in which at least the alignment surface A of the optical waveguide according to any one of (1) to (4) and the external casing are aligned.
(7) The method of manufacturing an optical waveguide assembly according to (6), wherein at least one of the alignment surface B, the alignment surface C, and the alignment surface D is aligned with the external housing.
(8) At least one of the alignment surface A, the alignment surface B, the alignment surface C, and the alignment surface D and the external housing are fixed with an adhesive (6). Or the manufacturing method of the optical waveguide assembly as described in (7).
(9) The optical waveguide assembly according to (8), wherein the adhesive is a photo-curable adhesive, and the outer casing is transmissive to actinic rays that cure the adhesive. Production method.
(10) After manufacturing the optical waveguide assembly by the method for manufacturing an optical waveguide assembly according to any one of (6) to (9), an optical fiber is optically connected to the optical waveguide of the optical waveguide assembly. The manufacturing method of the optical module which connects an optical connector to the said optical fiber.

  According to the present invention, it is easy to align an optical axis with a separate optical member such as a photoelectric conversion element or an optical fiber connector, and therefore, an optical waveguide excellent in optical signal propagation efficiency, a manufacturing method thereof, and an optical waveguide assembly A manufacturing method and a manufacturing method of an optical module can be provided.

It is the top view and side view which show the optical waveguide of this invention. It is the top view and side view which show the optical waveguide of this invention. It is sectional drawing from the upper surface and side surface direction which shows the optical waveguide assembly which consists of the optical waveguide and housing | casing of this invention. It is sectional drawing from the upper surface and side surface direction which shows the optical waveguide assembly which consists of the optical waveguide and housing | casing of this invention. It is sectional drawing from the upper surface and side surface direction which shows the optical waveguide assembly which consists of the optical waveguide and housing | casing of this invention. It is a side view which shows the optical module which consists of an optical waveguide of this invention, a housing | casing, an optical fiber, and an optical connector. It is sectional drawing from the upper surface and side surface direction which shows the optical waveguide assembly which consists of the optical waveguide of the comparative example 1, and a housing | casing.

  As shown in FIG. 1, the optical waveguide of the present invention includes a substrate 5, an optical signal transmission core pattern 1, a clad layer 2 in which the optical signal transmission core pattern 1 is embedded, an optical path conversion mirror 3, and the optical path conversion mirror. And an inclined surface 4 in which a positional correlation is ensured. Hereinafter, each member used in the present invention will be described in detail.

[Core pattern for optical signal transmission]
The optical signal transmission core pattern 1 can be formed, for example, by laminating a resin layer for forming a core layer, and exposing and developing. The core layer forming resin may be a composition containing a plurality of components.
The core layer forming resin preferably has a refractive index higher than that of the clad layer 2 and can be patterned by actinic rays. The method for forming the core layer forming resin layer before patterning is not limited. For example, the core layer forming resin may be laminated by dissolving the resin for forming the core layer in a solvent. A resin film may be laminated.

  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. When the thickness of the core layer after finishing 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 formation of the optical waveguide, and when it is 100 μm or less, There is an advantage that the coupling efficiency is improved in coupling with the light emitting / receiving element or the optical fiber after the optical waveguide is formed. From the above viewpoint, the thickness of the film is preferably in the range of 30 to 90 μm, and the film thickness may be appropriately adjusted in order to obtain the thickness.

  As the core layer forming resin, it is preferable to use a resin that is transparent to an optical signal to be used and can form a pattern with actinic rays.

[Clad layer]
The clad layer 2 in the present invention can be formed, for example, by laminating a resin layer for forming a clad layer, and exposing and developing. The clad layer forming resin may be a composition containing a plurality of components.
The clad layer forming resin used in the present invention is not particularly limited as long as it is a resin that has a lower refractive index than the optical signal transmission core pattern 1 and is cured by light or heat, and a thermosetting resin or a photosensitive resin is preferable. Can be used for The clad layer is usually formed by being divided into a lower clad layer and an upper clad layer, and these clad layer forming resins may be the same or different in the clad layer 2 containing the same resin. The refractive index of the resin may be the same or different.

The method for laminating the clad layer forming resin layer is not particularly limited. For example, the clad layer forming resin film may be laminated by dissolving the clad layer forming resin in a solvent. May be laminated.
In the case of application, the method is not limited, and the clad layer forming resin may be applied by a conventional method.
The clad layer-forming resin film used for laminating can be easily manufactured by, for example, dissolving the clad layer-forming resin in a solvent, applying it to a support film (carrier film), and removing the solvent. .

  The thickness of the cladding layer 2 is not particularly limited, but the thickness after drying is preferably in the range of 5 to 500 μm. When the thickness is 5 μm or more, a clad thickness necessary for light confinement can be secured, and when the thickness is 500 μm or less, it is easy to control the film thickness uniformly. From the above viewpoint, the thickness of the clad layer 2 is more preferably 15 to 200 μm, and still more preferably 10 to 100 μm.

[Optical path conversion mirror]
The optical path conversion mirror 3 has a structure that optically converts an optical signal propagated through the optical signal transmission core pattern 1 extending in a direction parallel to the substrate plane in a direction substantially perpendicular to the substrate 5 and the cladding layer 2. There is no limitation, and an air reflection mirror formed by providing a 45 ° cutout in the core pattern 1 or a metal reflection mirror in which a reflective metal layer is formed in the cutout portion may be used.
The optical path conversion mirror 3 is formed by forming a notch in the optical signal transmission core pattern 1 using a dicing saw or the like, or after forming the cladding layer 2 on the optical signal transmission core pattern 1 using a dicing saw or the like. It can be formed by providing a notch, or an inclined pattern can be formed by using a photolithography process. The cutout may be provided so as to reach the lower cladding layer or the substrate.

[Inclined surface]
The inclined surface 4 is only required to have a positional correlation with the optical path conversion mirror 3, and the optical path conversion mirror and the inclined surface are preferably on the same plane or a parallel plane. There are a method in which a position to be cut when moving using a dicing saw or the like is moved by a certain amount, and a method in which the same mask is used when forming using a photolithography process.
If the inclined surface 4 is formed on the same surface as the optical path conversion mirror 3 in the step of forming the optical path conversion mirror 3, it is desirable to eliminate the influence of the repeatability of the processing machine. In addition, the inclined surface 4 and the optical path conversion mirror 3 A shorter distance is more preferable because it is less susceptible to distortion of the structure.

[Alignment surface A]
In the present invention, the alignment surface A <b> 11 is formed by all or part of the inclined surface 4.
The alignment surface A11 is not particularly limited as long as the alignment surface A11 is in a shape that contacts the outer casing and keeps the positional relationship between the optical waveguide and the outer casing constant, and the core pattern, the clad layer, and the substrate exceed 0 ° and 90 °. It may be a flat surface formed by providing a notch that is an inclined surface of less than, preferably 30 ° to 60 °, or a rectangular shape so that the substrate and the housing are fitted to the inclined surface. Or a V-groove and a protrusion shape. The alignment surface A11 can be produced according to the inclined surface 4.
In FIG. 1, an inclined surface 4 is provided on the optical waveguide, which is used as an alignment surface A <b> 11, and the tip of the substrate 5 is made longer than the inclined surface A to protect the inclined surface 4. FIG. 3 shows an optical waveguide assembly in which the alignment surface A and an external housing are aligned to face the alignment surface A.
3 is a cross-sectional view from the side surface direction of the optical waveguide assembly, and a view shown below the paper surface is a cross-sectional view from the top surface direction.

[Alignment surface B]
The alignment surface B12 is not particularly limited as long as the alignment surface B12 is one surface of the optical waveguide that forms an acute angle with the inclined surface 4 and is in contact with the external housing and maintains the positional relationship between the optical waveguide and the external housing constant. . When the optical waveguide is formed on the substrate 5, one surface of the optical waveguide is the lower surface of the plate-like substrate 5 (surface opposite to the surface where the optical waveguide is formed with respect to the substrate). When the waveguide is not formed on the substrate, one surface of the optical waveguide is the bottom surface of the cladding layer 2 or the core pattern 1. The alignment surface B12 is desirably a reference surface when the inclined surface 4 is formed because the correlation of the angle with the inclined surface 4 can be kept high.
Since the alignment surface B is in contact with the housing on two surfaces together with the alignment surface A, alignment and fixation are more reliable.
FIG. 4 shows a case where the optical waveguide is aligned and fixed to the housing by the alignment surface B and the alignment surface A. Since the housing and the two surfaces (positioning surfaces A and B) of the optical waveguide are in contact with each other, they slide up and down as shown in FIG.

[Alignment surface C, alignment surface D]
The alignment surfaces C13 and D14 are one surface of the optical waveguide that forms an acute angle with the alignment surface A11 and the alignment surface B12, and are in contact with the external housing to keep the positional relationship between the optical waveguide and the external housing constant. If it is a shape, there will be no limitation in particular. The alignment surfaces C13 and D14 are two side surfaces of the optical waveguide that intersect the inclined surface and are parallel to the longitudinal direction of the optical signal transmission core pattern.
When the optical waveguide is viewed as a cube, the six faces of the cube are called the front, back, top, bottom, right side, and left side, and there are inclined surfaces on the front, an optical path conversion mirror on the top, and a substrate or cladding on the bottom When there is a layer, the right side surface or the left side surface becomes the alignment surface C13 or the alignment surface D14. In FIG. 1, the right side surface is defined as an alignment surface D14, and the left side surface is defined as an alignment surface C13. The alignment surfaces C13 and D14 form a vertical surface with the alignment surface A and the alignment surface B.
The alignment surfaces C13 and D14 can be formed by processing the substrate 5, the cladding layer 2, and the core pattern 1. The shape of the alignment surface may be a shape that fits with the housing and is aligned and fixed.
If the alignment surfaces C13 and D14 are formed simultaneously when the core pattern 1 is processed, the positional relationship with the core pattern 1 can be formed with high accuracy, that is, the positional relationship between the housing, the core pattern, and the mirror is accurate. This is desirable.
The alignment surfaces C13 and D14 are aligned and fixed to the external housing together with the alignment surface A of the optical waveguide, or the alignment surface A and the alignment surface B, and two, three, or four surfaces. So they are more certain.
FIG. 2 shows an example in which the alignment surfaces C13 and D14 are guide core patterns. As will be described in the examples described later, when the optical signal transmission core pattern is manufactured, the core layer forming resin is left in the portion that becomes the side surface of the optical waveguide to form a guide core pattern that is wider than the width of the substrate. These are referred to as alignment surfaces C13 and D14. Thereby, it fixes to the housing | casing which has a shape fitted with the convex alignment surfaces C13 and D14, and a position is match | combined.
In FIG. 2, the lower clad layer is formed so as to have a narrow width so that the substrate is exposed. By using a casing that fits the lower clad layer, alignment and fixation are ensured.

[substrate]
The substrate 5 is preferably used for the optical waveguide of the present invention, and the material of the substrate 5 that can be used is not particularly limited. For example, a glass epoxy resin substrate, a ceramic substrate, a glass substrate, a silicon substrate, a plastic substrate, a metal substrate, Examples include a substrate with a resin layer, a substrate with a metal layer, a plastic film, a plastic film with a resin layer, a plastic film with a metal layer, and an electric wiring board.
The thickness of the substrate 5 is preferably 5 μm to 1 mm, and more preferably 10 μm to 100 μm. If the thickness of the substrate 5 is 5 μm or more, it is preferable from the viewpoint of the rigidity of the substrate 5, and if it is 1 mm or less, the light signal reflected by the optical path conversion mirror 3 can be received by a light receiving element or an optical fiber before spreading. Therefore, it is preferable.

[Case]
The housing 6 only needs to hold the optical waveguide. If a hole or groove for fixing the optical fiber optically connected to the optical waveguide or a pin hole for alignment with the photoelectric conversion element is formed in the housing 6, the optical fiber and the photoelectric conversion element This is desirable because it can be easily assembled. In the case of fixing an optical waveguide or an optical fiber using an adhesive, it is desirable that a hole or a groove for pouring the adhesive from the outside is formed because the adhesive can be more reliably bonded.
As a material for forming the housing 6, resin, metal, ceramics, or the like can be used. In the case of fixing an optical waveguide or an optical fiber using a photo-curable adhesive, it is preferable to use a material that transmits an actinic ray for adhesion because the material can be bonded more firmly. The housing 6 can be formed by a method such as molding or shaving.
As shown in FIG. 5, when the optical waveguide is inserted into the casing 6 and the optical waveguide and the casing are aligned on the alignment surface A, the optical waveguide fits into the casing and does not return. Thus, it is preferable to provide a protrusion. As a result, the optical waveguide and the housing are more reliably fixed.

[Optical module]
The optical module of the present invention comprises an optical waveguide assembly in which an optical waveguide is fixed to a housing, an optical fiber optically connected to the optical waveguide of the optical waveguide assembly, and an optical connector connected to the optical fiber.
FIG. 6 shows a cross-sectional view of the optical module. The optical fiber 21 is optically connected to the optical signal transmission core pattern of the optical waveguide of the optical waveguide assembly including the optical waveguide and the housing, and the optical connector 22 is optically connected to the other end of the optical fiber 21. The
By setting it as such an optical module, optical axis alignment with separate optical members, such as a photoelectric conversion element and an optical fiber connector, becomes easy, and it is excellent in optical signal propagation efficiency.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

Example 1
<Preparation of a resin film for forming a cladding layer>
[Production of (A) (meth) acrylic polymer (base polymer)]
46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate were weighed in a flask equipped with a stirrer, a cooling pipe, a gas introduction pipe, a dropping funnel, and a thermometer, and stirred while introducing nitrogen gas. . The liquid temperature was raised to 65 ° C., 47 parts by mass of methyl methacrylate, 33 parts by mass of butyl acrylate, 16 parts by mass of 2-hydroxyethyl methacrylate, 14 parts by mass of methacrylic acid, 2,2′-azobis (2,4-dimethylvaleronitrile ) A mixture of 3 parts by mass, 46 parts by mass of propylene glycol monomethyl ether acetate and 23 parts by mass of methyl lactate was added dropwise over 3 hours, followed by stirring at 65 ° C. for 3 hours, and further stirring at 95 ° C. for 1 hour. A) A (meth) acrylic polymer solution (solid content: 45% by mass) was obtained.

[Preparation of resin varnish for forming clad layer]
As a base polymer, 84 parts by mass (solid content 38 parts by mass) of the (A) (meth) acrylic polymer solution (solid content 45% by mass), (B) urethane (meth) acrylate having a polyester skeleton as a photocuring component ( Shin-Nakamura Chemical Co., Ltd. “U-200AX”) 33 parts by mass, urethane (meth) acrylate having a polypropylene glycol skeleton (Shin-Nakamura Chemical Co., Ltd. “UA-4200”) 15 parts by mass, (C) heat As a curing component, 20 parts by mass of a polyfunctional block isocyanate solution (solid content: 75% by mass) obtained by protecting an isocyanurate type trimer of hexamethylene diisocyanate with methyl ethyl ketone oxime (“Sumijour BL3175” manufactured by Sumika Bayer Urethane Co., Ltd.) 15 parts by mass of solid content), (D) as photopolymerization initiator, 1- 4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one ("IRGACURE 2959" manufactured by BASF) 1 part by mass, bis (2,4,6-trimethylbenzoyl) 1 part by mass of phenylphosphine oxide (“Irgacure 819” manufactured by BASF) and 23 parts by mass of propylene glycol monomethyl ether acetate as an organic solvent for dilution were mixed with stirring. After pressure filtration using a polyflon filter having a pore size of 2 μm (“PF020” manufactured by Toyo Roshi Kaisha, Ltd.), degassing was performed under reduced pressure to obtain a resin varnish for forming a cladding layer.

[Preparation of resin film for forming clad layer]
The resin varnish for forming a clad layer obtained above is coated on a non-treated surface of a PET film (“Cosmo Shine A4100” manufactured by Toyobo Co., Ltd., thickness 50 μm) as a support film. Applying using Hirano Tech Seed Co., Ltd., drying at 100 ° C. for 20 minutes, and then applying a surface release treatment PET film (“Purex A31” manufactured by Teijin DuPont Films Ltd., thickness 25 μm) as a protective film to form a cladding layer A resin film was obtained.
At this time, the thickness of the resin layer formed from the clad layer forming resin varnish can be arbitrarily adjusted by adjusting the gap of the coating machine, and the film thickness will be described later.

<Preparation of core layer forming resin film>
(A) As a base polymer, 26 parts by mass of a phenoxy resin (trade name: Phenotote YP-70, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), and (B) 9,9-bis [4- ( 2-acryloyloxyethoxy) phenyl] fluorene (trade name: A-BPEF, manufactured by Shin-Nakamura Chemical Co., Ltd.) and 36 parts by mass of bisphenol A type epoxy acrylate (trade name: EA-1020, manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 36 parts by mass, (C) as a photopolymerization initiator, 1 part by mass of bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (trade name: Irgacure 819, manufactured by BASF), and 1- [4- (2-Hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one (trade name: Irgacure 2959, ASF varnish is prepared in the same manner and under the same conditions as the above clad layer forming resin varnish except that 1 part by weight and 40 parts by weight of propylene glycol monomethyl ether acetate are used as the organic solvent. did. 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 obtained above is the same as in the above production example on the non-treated surface of a PET film (trade name: Cosmo Shine A1517, manufactured by Toyobo Co., Ltd., thickness: 16 μm) as a support film. After coating and drying by the method, a release PET film (trade name: PUREX A31, Teijin DuPont Films Co., Ltd., thickness: 25 μm) is pasted as a protective film so that the release surface is on the resin side, forming a core layer A resin film was obtained.
At this time, the thickness of the resin layer formed from the core layer forming resin varnish can be arbitrarily adjusted by adjusting the gap of the coating machine, and the film thickness will be described later.

<Fabrication of optical waveguide>
[Formation of lower cladding layer]
A polyimide film (polyimide; Upilex RN (manufactured by Ube Industries, Ltd.), thickness: 25 μm) having a length of 150 mm and a width of 150 mm is used as the substrate 5, and the above-obtained 45 μm-thick cladding layer is formed on one surface thereof. After the protective film of the resin film is peeled off, a vacuum pressure laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) is used to vacuum the pressure to 500 Pa or less, and the pressure is 0.4 MPa, the temperature is 110 ° C., and the pressurization time is 30. Lamination was performed by thermocompression bonding under the conditions of seconds. Subsequently, using a UV exposure machine (EXM-1172, manufactured by Oak Manufacturing Co., Ltd.), UV light (wavelength 365 nm) was irradiated at 3.0 J / cm ² from the support film side of the resin film for forming the clad layer, and the support film. After peeling off, the film was dried and cured at 170 ° C. for 1 hour to form the lower cladding layer 2.

[Formation of optical signal transmission core pattern and guide core pattern]
Next, on the clad layer 2 (lower part) formed above, after the protective film is peeled off the 50 μm-thick core layer-forming resin film obtained above, a roll laminator (HLM manufactured by Hitachi Chemical Technoplant Co., Ltd., HLM) -1500) under the conditions of a pressure of 0.4 MPa, a temperature of 50 ° C., and a laminating speed of 0.2 m / min, and then using the above-described vacuum pressure laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.), 500 Pa After vacuuming below, thermocompression bonding was performed under conditions of a pressure of 0.4 MPa, a temperature of 70 ° C., and a pressurization time of 30 seconds.

Subsequently, by using the negative photomask for forming the optical signal transmission core pattern 1 and the guide core pattern, and the ultraviolet exposure machine, ultraviolet rays (wavelength 365 nm) are emitted from the support film side at 0.8 J / cm ² . Irradiation was followed by post-exposure heating at 80 ° C. for 5 minutes. The optical signal transmission core pattern 1 has two cores extending in the center of the optical waveguide, and the guide core pattern has linear core patterns on both edges of the optical waveguide (FIG. 2). reference).
Thereafter, the PET film as the support film was peeled off and etched using a developer (propylene glycol monomethyl ether acetate / N, N-dimethylacetamide = 8/2, mass ratio). Then, it wash | cleaned using the washing | cleaning liquid (isopropanol), and heat-dried at 100 degreeC for 10 minute (s), and formed the optical signal transmission core pattern 1 and the guide core pattern.

[Clad layer (top) formation]
From the obtained core pattern, after removing the protective film from the 55 μm-thick clad layer forming resin film obtained above, a vacuum pressure laminator (manufactured by Meiki Seisakusho Co., Ltd., MVLP-500) was used. After vacuuming to 500 Pa or less, lamination was performed by thermocompression bonding under conditions of a pressure of 0.4 MPa, a temperature of 110 ° C., and a pressurization time of 30 seconds. Subsequently, using a negative photomask having an opening to expose a part of the guide core pattern and the ultraviolet exposure machine, ultraviolet light (wavelength 365 nm) is emitted from the support film side of the resin film for forming the cladding layer. Irradiate at 0.0 J / cm ² , peel off the support film, perform post-exposure heating at 80 ° C. for 5 minutes, develop, and wash to form the cladding layer 2 (upper part) where a part of the guide core pattern is exposed (See FIG. 2).

[Formation of optical path conversion mirror]
Using the dicing saw (DAC552, manufactured by DISCO Corporation) from the clad layer 2 (upper) side of the obtained optical waveguide, the 45 ° optical path conversion mirror 3 and the alignment surface A were formed.

[Formation of waveguide outline]
The periphery of the obtained optical waveguide was cut using a dicing saw (DAC552, manufactured by DISCO Corporation, 90 ° blade) to form the outer shape of the waveguide. At that time, as shown in FIG. 2, the base material and the lower clad were half-cut so that the guide core pattern had a waveguide outer shape on the two outer sides.
Thereby, the optical waveguide with a mirror which has the alignment surface A was obtained.

[Position accuracy measurement with case (X and Y direction)]
The produced optical waveguide substrate was fitted into a case produced by injection molding, and the positional relationship between the hole formed in the case by molding and the light beam emitted from the mirror was measured. Specifically, the positional relationship between the center of the light beam that was irradiated with halogen lamp light horizontally from the edge of the core exposed by cutting the outer shape and changed the optical path in the vertical direction via a mirror, and the center of the hole in the housing was measured. (MX61L, manufactured by Olympus Corporation) was used for imaging, and measurement was performed using image analysis software (NIS Elements, image integration software, manufactured by Nikon Corporation). The core width direction was defined as the X direction, and the core traveling direction was defined as the Y direction.
The difference between the measured average value and the design value obtained as shown in Table 1 below was 0.6 μm in the X direction and 1.1 μm in the Y direction. The standard deviation of the measured values was 0.79 μm in the X direction and 0.93 μm in the Y direction.

[Position accuracy measurement with case (Z direction)]
The produced optical waveguide substrate was fitted into a case produced by injection molding, and the positional relationship between the outer edge of the case and the light beam emitted from the core was measured. Specifically, a halogen lamp light is vertically irradiated onto the optical path conversion mirror, and the distance between the center of the light beam emitted from the end of the core exposed by cutting the outer shape through the core and the bottom of the housing is measured with a semiconductor inspection microscope (MX61L, The image was taken using Olympus Corporation, and measured using image analysis software (NIS Elements, Nikon Corporation). This distance is defined as the Z direction, which is a direction component perpendicular to the X direction and the Y direction.
The difference between the measured average value and the design value was −0.5 μm. The standard deviation of the obtained measured value was 1.00 μm.

(Example 2)
In addition to Example 1, an ultraviolet thermosetting adhesive was dropped between the waveguide and the case, and after irradiation with 1 J / cm ^{2 of} ultraviolet rays, heat curing was performed at 100 ° C. for 1 hour using a hot air drying furnace. The waveguide and the case were fixed. When the positional accuracy (X, Y direction and Z direction) with respect to the housing was measured in the same manner as in Example 1, the difference between the obtained measurement average value and the design value was 1.4 μm in the X direction, and 0. It was 8 μm and −1.4 μm in the Z direction. The standard deviations of the measured values were 1.09 μm in the X direction, 0.92 μm in the Y direction, and 1.06 μm in the Z direction, which were the same as in Example 1.

(Example 3)
When the outer shape of the optical waveguide of Example 1 was cut, an optical waveguide was produced in the same manner except that the guide core was not exposed and the outer shape was formed with a dicing blade (see FIG. 1).
When the positional accuracy (X, Y direction and Z direction) with respect to the housing was measured in the same manner as in Example 1, the difference between the obtained measurement average value and the design value was −4.4 μm in the X direction and 1 in the Y direction. 0.0 μm and −0.5 μm in the Z direction. The standard deviations of the measured values were 6.28 μm in the X direction, 1.00 μm in the Y direction, and 0.99 μm in the Z direction, and the variation in the X direction was larger than that in Example 1.

(Comparative Example 1)
In Example 3, when the outer shape of the optical waveguide is cut, the alignment surface A is cut with a dicing blade, and the optical waveguide is formed in the same manner except that the outer shape is formed so that the blade cutting surface becomes the alignment surface A. It produced (refer FIG. 7).
When the positional accuracy (X, Y direction and Z direction) with respect to the housing was measured in the same manner as in Example 1, the difference between the obtained measurement average value and the design value was 10.9 μm in the X direction and 4. It was 7 μm and −3.6 μm in the Z direction. The standard deviations of the measured values were 6.20 μm in the X direction, 3.47 μm in the Y direction, and 9.08 μm in the Z direction, and the variations in the X direction, Y direction, and Z direction were larger than those in Example 1.
Table 1 shows the positional relationship between the housings of Examples 1 to 3 and Comparative Example 1 and the reflected light from the optical path conversion mirror, and the measurement.

  The first embodiment in which the guide core pattern is provided on the two sides of the outer shape shown in FIG. 2 is compared with the third embodiment in which the guide core pattern is not provided as shown in FIG. The difference between the design value and the standard deviation are both small, and the positional accuracy is better. In addition, fixing using an adhesive (Example 2) has the same positional accuracy as Example 1 without using it, and can be fixed more firmly. The comparative example 1 which does not provide an inclined surface irrespective of this invention is inferior to an Example in position accuracy in a X, Y, Z direction.

  The optical waveguide and the optical waveguide assembly of the present invention can be easily aligned with an optical fiber connector or a photoelectric conversion element, and can be applied to various fields such as various optical devices and optical interconnections. An optical module comprising an optical fiber optically connected to an optical waveguide and an optical connector connected to the optical fiber is excellent in optical signal propagation efficiency because of its good alignment, and is separate from a photoelectric conversion element, an optical fiber connector, etc. It becomes easy to align the optical axis with the optical member.

1. 1. Optical signal transmission core pattern 2. Clad layer 3. Optical path conversion mirror Inclined surface 5. Substrate 6. Housing 11. Alignment surface A
12 Alignment surface B
13. Alignment surface C
14 Alignment surface D
21. Optical fiber 22. Optical connector

Claims (10)

  The optical signal transmission core pattern, the cladding layer in which the optical signal transmission core pattern is embedded, the optical path conversion mirror provided in the optical signal transmission core pattern, and the correlation between the positions of the optical path conversion mirror are secured. An optical waveguide having an inclined surface, wherein the inclined surface is an alignment surface A with an external housing.   The optical waveguide according to claim 1, wherein the optical path conversion mirror and the inclined surface are coplanar or parallel.   The optical waveguide according to claim 1, wherein one surface of the optical waveguide forming an acute angle with the inclined surface is an alignment surface B with the external casing.   Two surfaces C or D that intersect the inclined surface and form two side surfaces of the optical waveguide parallel to the longitudinal direction of the optical signal transmission core pattern are the alignment surface C or alignment with the external casing. It is the surface D, The optical waveguide as described in any one of Claims 1-3. A method for producing an optical waveguide according to any one of claims 1 to 4,
A method for manufacturing an optical waveguide, wherein the alignment surface C or the alignment surface D to be a guide core pattern is formed simultaneously with the optical signal transmission core pattern.   The manufacturing method of the optical waveguide assembly with which the said alignment surface A of the optical waveguide as described in any one of the said Claims 1-4 and the said external housing | casing are aligned.   The method of manufacturing an optical waveguide assembly according to claim 6, wherein at least one of the alignment surface B, the alignment surface C, and the alignment surface D is aligned with the external housing.   8 or 7, wherein at least one of the alignment surface A, the alignment surface B, the alignment surface C, and the alignment surface D and the external housing are fixed via an adhesive. A method for manufacturing the optical waveguide assembly as described.   The method of manufacturing an optical waveguide assembly according to claim 8, wherein the adhesive is a photocurable adhesive, and the external casing is transmissive to actinic rays that cure the adhesive.   An optical waveguide assembly is manufactured by the method for manufacturing an optical waveguide assembly according to any one of claims 6 to 9, and an optical fiber is optically connected to the optical waveguide of the optical waveguide assembly. An optical module manufacturing method for connecting an optical connector

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