JP2016118594A - Method for manufacturing polymer optical waveguide having positioning structure, polymer optical waveguide manufactured thereby, and optical module using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a polymer optical waveguide having a salient and a recess for positioning, a polymer optical waveguide manufactured thereby, and an optical module using the same.SOLUTION: A method for manufacturing a polymer optical waveguide includes the steps of: (A) laminating a resin film 16 for lower clad formation on a base material 11 having a shape for forming a salient 42 or a recess for positioning and a photomask alignment mark 13 for core pattern formation in a polymer optical waveguide 41; (B) laminating a resin film 21 for core formation; (C) performing alignment using the alignment mark 13 provided in the base 11 in (A) and forming a core pattern by exposure; and (D) laminating a resin film 36 for upper clad formation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polymer optical waveguide used for optical interconnection, and more particularly to a polymer optical waveguide capable of simple and highly accurate positioning, a manufacturing method thereof, and an optical module using the same.

In recent years, in high-speed and high-density signal transmission between electronic devices and between wiring boards, in conventional transmission using electrical wiring, the mutual interference and attenuation of signals become barriers, and the limits of high-speed and high-density have begun to appear. In order to overcome this problem, a technique for optically connecting electronic elements and wiring boards, so-called optical interconnection, has been studied. As an optical transmission line, polymer optical waveguides are attracting attention because they are easy to process, low cost, have a high degree of freedom in wiring, and can be densified.
As a form of the polymer optical waveguide, a flexible type having no hard support substrate is considered preferable from the viewpoint of handleability.

As an application of the polymer optical waveguide, there is an interconnection between photoelectric composite wiring boards on which a laser diode or a photodiode is mounted. At that time, it is necessary to align the laser waveguide, the photodiode mounted on the polymer optical waveguide and the photoelectric composite wiring board, or the optical waveguide to which these are connected with high accuracy. As a method for that purpose, there is known a method (for example, Patent Document 1) in which a positioning convex portion is provided on the upper clad of the polymer optical waveguide and is aligned with a fitting groove formed in a silicon photonics chip. Yes.
However, in this method, a process for providing the convex portions for positioning is necessary in addition to the normal polymer optical waveguide manufacturing process, and there is a concern about an increase in manufacturing time and cost.

JP 2014-81586 A

  The present invention has been made to solve the above-described problems, and provides a method for manufacturing a polymer optical waveguide capable of simple and highly accurate positioning, a polymer optical waveguide manufactured thereby, and an optical module using the same. The purpose is to provide.

  As a result of intensive studies, the present inventors have found a method of forming a convex portion or a concave portion for positioning at the time of forming the lower clad by laminating a resin film for forming the lower clad on a base material having a specific shape. .

  That is, the present invention provides [1] (A) a resin for forming a lower clad on a substrate having a shape for forming a convex or concave portion for positioning in a polymer optical waveguide and an alignment mark for a core pattern forming photomask. A step of laminating a film, (B) a step of laminating a resin film for core formation, (C) a step of aligning and exposing using an alignment mark provided on the base material of (A) to form a core pattern ( And D) laminating a resin film for forming an upper clad.

The present invention also relates to [2] a polymer optical waveguide manufactured by the method described in [1].
The present invention also relates to an optical module having a structure in which the polymer optical waveguide according to the above [2] and a wiring board are fitted.
Furthermore, the present invention relates to [4] the optical module according to [3], wherein the wiring board has a silicon photonics chip.

  According to the manufacturing method of the present invention, a polymer optical waveguide having an alignment structure with an optoelectric composite wiring board can be manufactured easily and with high accuracy.

It is a figure explaining the manufacturing method of the polymer optical waveguide of this invention. It is a figure explaining the manufacturing method of the polymer optical waveguide of this invention. It is a figure explaining the optical module using the polymer optical waveguide of this invention. It is a figure explaining the optical module using the polymer optical waveguide of this invention.

  Hereinafter, an example of a method for producing a polymer optical waveguide of the present invention will be described with reference to FIG.

  FIG. 1 (1) shows a side sectional view of the substrate 11 used in the present invention. The substrate 11 includes a concave shape 12 for forming a positioning convex portion 42 (see FIG. 1 (7)) in a polymer optical waveguide, and a photomask alignment mark 13 for forming a core pattern. Such a substrate is not particularly limited as long as it has the above-mentioned shape, and for example, a material obtained by processing a copper foil of a polyimide film with a copper foil so as to have a desired shape can be used. . In addition, a metal, glass, semiconductor material, or the like processed into a desired shape may be used. The shape of the concave shape is not particularly limited as long as the object can be achieved, and examples thereof include a circular shape, a rectangular shape, a cross shape, or a combination thereof as viewed from above. The size is not particularly limited, but the diameter or the length of one side is preferably 100 μm or more and more preferably 1000 μm or less from the viewpoint of ensuring fitting. Further, the height is preferably 10 μm or more, and more preferably 500 μm or less for the same reason.

  FIG. 1B shows a state in which the concave shape 12 and the alignment mark 13 provided in the base material 11 are embedded by laminating the resin film 16 for forming the lower clad. As the resin film for forming the lower clad, a resin film that is cured by using light, heat, or a combination thereof, for example, a resin film described in JP 2013-119605 A or JP 1-3302308 A can be used. . The thickness of the resin film for forming the lower clad is not particularly limited, but generally 5-100 μm is used. As a laminating apparatus, a roll laminator or a flat plate laminator can be used. From the viewpoint of following the concave shape and flatness on the upper side of the lower clad (the side on which the core-forming resin film is in contact), a vacuum is applied. It is preferable to use a pressure laminator (for example, MVLP500 / 600 manufactured by Meiki Seisakusho Co., Ltd.).

  FIG. 1 (3) to FIG. 1 (4) show a core pattern forming method. First, the core-forming resin film 21 is formed by lamination in FIG. As the core-forming resin film, for example, a resin film whose refractive index increases by light irradiation can be used. As such a resin film, for example, a resin film described in JP-A-1-302308 can be used. . The thickness of the core-forming resin film is not particularly limited, but is generally 5 to 100 μm. A roll laminator or a flat plate laminator can be used as an apparatus for laminating.

  FIG. 1 (4) shows a core pattern exposure method. The alignment mark 27 of the photomask 26 and the alignment mark 13 provided on the base material can be aligned to expose the core pattern. By this method, since the positional relationship between the positioning convex portion 42 formed in the polymer optical waveguide and the core 31 is uniquely determined, a polymer optical waveguide in which these are aligned with high accuracy can be manufactured.

As mentioned above, although the example using the resin film which increases the refractive index of a light irradiation part as a resin film for core formation was demonstrated, you may use the resin film from which the refractive index of the part reduces by light irradiation instead.
When such a core-forming resin film is used, development is not particularly required, but development may be performed using a developer such as an alkaline aqueous solution as necessary.

  Subsequently, as shown in FIG. 1 (5), the upper clad forming resin film 36 is laminated on the core forming resin film. As the resin film for forming the upper clad, a resin film that is cured by using light, heat, or a combination thereof, for example, a resin film described in JP 2013-119605 A or JP 1-3302308 A can be used. . The thickness of the upper clad forming resin film is not particularly limited, but generally 5-100 μm is used. As an apparatus for laminating, a roll laminator or a flat plate laminator can be used.

  Finally, the polymer optical waveguide 41 having the positioning convex portions 42 can be manufactured by removing the base material by a method such as peeling and processing it into a desired outer shape (FIG. 1 (6)).

  The manufacturing method of the polymer optical waveguide having the positioning convex portion has been described above, but the polymer optical waveguide having the positioning concave portion can also be manufactured by the same method. In this case, as shown in FIG. 2, the relationship of the unevenness provided on the substrate may be reversed from that in FIG. The method will be described below.

  FIG. 2A shows a substrate 51 used in the present invention. The substrate 51 includes a convex shape 52 for forming a positioning concave portion 82 (see FIG. 2 (7)) in the polymer optical waveguide, and a photomask alignment mark 53 for forming a core pattern. Such a substrate is not particularly limited as long as it has the above-mentioned shape, and for example, a material obtained by processing a copper foil of a polyimide film with a copper foil so as to have a desired shape can be used. . In addition, a metal, glass, semiconductor material, or the like processed into a desired shape may be used. The shape of the convex shape is not particularly limited as long as the object is achieved, and examples thereof include a circle, a rectangle, a cross, or a combination thereof. Moreover, although there is no restriction | limiting in particular also about the magnitude | size, From a viewpoint of ensuring a fitting, it is preferable that a diameter or the length of one side is 100 micrometers or more, and it is more preferable that it is 1000 micrometers or less. The height is preferably 5 μm or more and more preferably 100 μm or less for the same reason.

  FIG. 2B shows a state in which the concave shape 52 and the alignment mark 53 provided in the base material 51 are embedded by laminating the resin film 56 for forming the lower clad. As the resin film for forming the lower clad, a resin film that is cured by using light, heat, or a combination thereof, for example, a resin film described in JP 2013-119605 A or JP 1-3302308 A can be used. . The thickness of the resin film for forming the lower clad is not particularly limited, but generally 5-100 μm is used. As a laminating apparatus, a roll laminator or a flat plate laminator can be used. From the viewpoint of following the concave shape and flatness on the upper side of the lower clad (the side on which the core-forming resin film is in contact), a vacuum is applied. It is preferable to use a pressure laminator (for example, MVLP500 / 600 manufactured by Meiki Seisakusho Co., Ltd.).

  FIG. 2 (3) to FIG. 2 (4) show a core pattern forming method. First, the core-forming resin film 61 is formed by lamination in FIG. As the core-forming resin film, a resin film whose refractive index increases upon light irradiation can be used. As such a resin film, for example, a resin film described in JP-A-1-302308 can be used. The thickness of the core-forming resin film is not particularly limited, but is generally 5 to 100 μm. A roll laminator or a flat plate laminator can be used as an apparatus for laminating.

  FIG. 2 (4) shows a core pattern exposure method. The alignment mark 67 of the photomask 66 and the alignment mark 53 provided on the base material are aligned, and the core pattern is exposed. By this method, the positional relationship between the positioning convex portion 82 formed in the polymer optical waveguide and the core 71 is uniquely determined, so that a polymer optical waveguide in which these are aligned with high accuracy can be manufactured.

  As mentioned above, although the example using the resin film which the refractive index of a light irradiation part increases as a core formation resin film was demonstrated, you may use the resin film from which the refractive index of the part reduces by light irradiation instead.

  Subsequently, an upper clad forming resin film 76 is laminated, and a core pattern is embedded as shown in FIG. As the resin film for forming the upper clad, a resin film that is cured by using light, heat, or a combination thereof, for example, a resin film described in JP 2013-119605 A or JP 1-3302308 A can be used. . The thickness of the upper clad forming resin film is not particularly limited, but generally 5-100 μm is used. A roll laminator or a flat plate laminator can be used as a laminating device. From the viewpoint of core pattern embedding followability and upper clad flatness, a vacuum pressure laminator (eg, manufactured by Meiki Seisakusho Co., Ltd.) MVLP 500/600) is preferably used.

  Finally, the polymer optical waveguide 81 having the positioning convex portions 82 can be manufactured by removing the base material by a method such as peeling and processing it into a desired outer shape (FIG. 2 (7)).

  FIG. 3 shows an optical module using a polymer optical waveguide having a positioning convex portion 106 manufactured according to the present invention. FIG. 3A illustrates the assembly of the optical module, and FIG. 3B illustrates the optical coupling structure of the assembled optical module.

  The positioning convex portion 106 formed on the polymer optical waveguide 101 is fitted into various wiring boards, for example, the positioning concave portion 166 provided on the photoelectric composite substrate 161. As a result, the core 111 of the polymer optical waveguide 101 and the core 181 of the optoelectric composite substrate 161 are positioned and connected via the respective optical path conversion units 116 and 171. Here, the optical path changing unit refers to a mirror structure, a grating coupler, or the like. In addition, the optoelectric composite substrate 161 refers to an electric wiring board or a semiconductor chip 186 and an optical element 176 (laser diode or photodiode). Among these, the polymer optical waveguide obtained by the present invention can be used for wiring boards that require extremely high precision alignment, such as wiring formation with silicon photonics chips in wiring boards having silicon photonics chips. preferable.

  Similarly, FIG. 4 shows an optical module using a polymer optical waveguide having a positioning recess 206 manufactured according to the present invention. FIG. 4A is a view for explaining assembly of the optical module, and FIG. 4B is a view for explaining an optical coupling structure of the assembled optical module.

  The positioning recess 306 formed in the polymer optical waveguide 301 is fitted into the positioning recess 366 provided in the photoelectric composite substrate 361. As a result, the core 311 of the polymer optical waveguide 301 and the core 381 of the optoelectric composite substrate 361 are positioned and connected via the respective optical path conversion units 316 and 371. Here, the optical path changing unit refers to a mirror structure, a grating coupler, or the like. In addition, the optoelectric composite substrate 361 indicates an electric wiring board or a semiconductor chip 386 and an optical element 376 (laser diode or photodiode).

  ADVANTAGE OF THE INVENTION According to this invention, the polymer optical waveguide which has the convex part or recessed part for positioning can be manufactured simply and with high precision.

DESCRIPTION OF SYMBOLS 11 Base material 12 Concave shape 13 Photomask alignment mark 16 Lower clad formation resin film 21 Core formation resin film 26 Photomask 27 Alignment mark 31 Core 36 Upper clad formation resin film 41 Polymer optical waveguide 42 Positioning convex part 51 Substrate 52 Convex 53 Photomask alignment mark 56 Lower clad forming resin film 61 Core forming resin film 66 Photomask 67 Alignment mark 71 Core 76 Upper clad forming resin film 81 Polymer optical waveguide 82 Positioning recess 101 Polymer light guide Waveguide 106 Positioning convex portion 111 Core 116 Optical path changing portion 161 Photoelectric composite substrate 166 Positioning concave portion 171 Optical path changing portion 176 Optical element 181 Core 186 Electric wiring board or Conductor chip 201 optical module 301 polymer optical waveguide 306 positioning depression 311 core 316 optical path changing unit 361 optoelectric composite substrate 366 positioning protrusions 371 optical path conversion portion 376 optical element 381 core 386 electrical wiring board or a semiconductor chip 401 optical module

Claims (4)

  (A) A step of laminating a resin film for forming a lower clad on a substrate having a shape for forming a convex or concave portion for positioning and an alignment mark of a photomask for forming a core pattern, (B) laminating a resin film for forming a core A step of forming a core pattern by aligning and exposing using the alignment mark provided on the substrate of (A), and (D) laminating a resin film for forming an upper clad. Manufacturing method of optical waveguide.   A polymer optical waveguide manufactured by the method according to claim 1.   An optical module having a structure in which the polymer optical waveguide according to claim 2 is fitted to a wiring board.   The optical module according to claim 3, wherein the wiring board has a silicon photonics chip.

Images