JP2008046334A - Optical transmission/reception module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmission/reception module in which the temperature rise due to the heat generation of a light emitting element is effectively suppressed, the light emission characteristic of the light emitting element is improved, and while an optical signal is transmitted and received via an optical waveguide formed in a flexible belt-shaped film which follows the deformation such as bending and torsion. <P>SOLUTION: In the bidirectional optical transmission/reception module 10, the end parts of a polymer optical waveguide film 11 are mounted on a submount 24 on an optical transmission/reception part 20 side, which is manufactured by an electroforming process, and a submount 25 on an optical transmission/reception part 21 side, which is made by the electroforming process, respectively, a light emitting element 22 is arranged so that the light emitted from the light emitting element 22 is made incident to a transmission optical waveguide via a reflection faces 15, and a light receiving element 23 is arranged so that the light emitted from the reception optical waveguide is received via the reflection face 15. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical transmission / reception module that transmits and receives an optical signal through an optical waveguide formed in a film, and more particularly, to an optical transmission / reception module that improves heat dissipation characteristics and light emission characteristics.

As an example of a conventional method for producing a polymer optical waveguide, for example, (1) a method in which a film is impregnated with a monomer, a core portion is selectively exposed, and a film is laminated by changing a refractive index (selective polymerization method) ,
(2) A method of forming a clad portion using reactive ion etching after applying a core layer and a clad layer (RIE method),
(3) A method of exposing and developing an ultraviolet curable resin obtained by adding a photosensitive material in a polymer material by photolithography (direct exposure method),
(4) Method using injection molding,
(5) Various methods such as a method of changing the refractive index of the core part by exposing the core part after applying the core layer and the clad layer (photo bleaching method) have been proposed.

  However, the selective polymerization method (1) has a problem in film lamination. The RIE method (2) and the direct exposure method (3) are expensive because they use a photolithography method. The injection molding method (4) has a problem in the accuracy of the obtained core diameter. The photo bleaching method (5) has a problem that the difference in refractive index between the core layer and the clad layer cannot be sufficiently obtained. Practical production methods include the RIE method (2) and the direct exposure method (3), but there is a problem in production cost as described above. In any of the production methods (1) to (5), it is practically unsuitable for forming a polymer optical waveguide on a flexible plastic substrate having a large area.

  On the other hand, as an example of a method for producing a polymer optical waveguide that is completely different from the conventional production method, there is a method for producing a polymer optical waveguide using a mold called, for example, a micromold method (for example, Patent Documents 1 to 3). reference.). According to the polymer optical waveguide manufacturing methods described in Patent Documents 1 to 3, it is possible to mass-produce optical waveguides very simply and at low cost. Moreover, although it is a simple manufacturing method, an optical waveguide with small optical waveguide loss can be produced stably. Furthermore, it is possible to produce an optical waveguide on a flexible plastic substrate that has been difficult to produce in the past. In addition, the manufacturing method of the polymer optical waveguide described in the said patent documents 1-3 is what the present applicant etc. proposed previously.

  By the way, recently, in IC technology and LSI technology, in order to improve the operation speed and the degree of integration, instead of performing high-density electrical wiring, optical wiring is performed between equipment devices, between boards in equipment equipment, and in chips. Is attracting attention. In particular, various elements for optical wiring using a surface emitting laser and a photodiode as a surface light receiving element, which are advantageous for power saving and surface array, have been proposed.

  As an example of such an element, for example, a polymer optical waveguide having a core and a clad surrounding the core is provided with a light emitting element and a light receiving element in the core / cladding direction, and light from the light emitting element is incident on the core. An optical element having an incident side mirror and an output side mirror for emitting light from the core to the light receiving element, and corresponding to an optical path from the light emitting element to the incident side mirror and from the output side mirror to the light receiving element Have proposed an optical element in which a cladding layer is formed and the light from the light emitting element and the light from the output side mirror are converged (see, for example, Patent Document 4).

  In addition, in an optical element in which light from a light emitting element is incident on a core end face of a polymer optical waveguide having a core and a clad surrounding the core, the light incident end face of the core is formed to be convex toward the light emitting element. An optical element in which light from the light emitting element is converged to suppress waveguide loss has been proposed (see, for example, Patent Document 5).

Further, there has been proposed an optoelectronic integrated circuit in which a polymer optical waveguide circuit is directly assembled on an optoelectronic circuit board in which electronic elements and optical elements are integrated (see, for example, Patent Document 6).
JP 2004-29507 A JP 2004-86144 A JP 2004-109927 A JP 2000-39530 A JP 2000-39531 A JP 2000-235127 A

  However, in the optical wiring methods proposed so far, the optical waveguide is fixed on the substrate together with the light emitting / receiving element and the mirror, and the degree of freedom of wiring is small compared to the electric wiring by wire, The optical wiring of the hinge part has a problem that it is difficult to apply to mobile devices such as mobile phones and thin personal computers that are often folded.

  On the other hand, optical fiber tapes made by collecting several strands of resin-coated optical fibers into tapes are used for optical wiring, but the optical fibers are made of quartz glass and are not easily bent. There was a problem of being small.

  For optical mounting, there is a method using a silicon (Si) submount, but the processing process using the Si RIE process is costly because the size of the substrate is limited. In addition, when a Si substrate is used, characteristics are worse than metals in terms of heat dissipation and high frequency characteristics.

  The present invention efficiently suppresses the temperature rise due to heat generation of the light emitting element and improves the light emitting characteristics of the light emitting element, and at the same time, is flexible and capable of following deformation such as bending and twisting. An object of the present invention is to provide an optical transceiver module capable of transmitting and receiving an optical signal through an optical waveguide formed in a belt-shaped polymer optical waveguide film.

[1] The present invention relates to a polymer optical waveguide film in which an optical waveguide is formed, a light emitting element, a first submount manufactured by an electroforming process, and an optical path changing device provided at one end of the optical waveguide. A first reflection surface is provided, and one end portion of the polymer optical waveguide film is placed on the first submount, and light emitted from the light emitting element changes an optical path at the first reflection surface. An optical transmitter having a configuration in which the light emitting element is arranged so as to be incident on the optical waveguide; a light receiving element; a second submount manufactured by an electroforming process; and the other end of the optical waveguide. A second reflection surface for converting the optical path, and placing the other end portion of the polymer optical waveguide film on the second submount, and light from the optical transmission portion is transmitted to the second submount. The light path is changed by the reflecting surface so that it can be received. Serial in an optical transceiver module, characterized by comprising a light receiving portion of the configuration of arranging the light-receiving element.

[2] Further, in the present invention, a polymer optical waveguide film in which a transmission optical waveguide and a reception optical waveguide are formed, and an optical signal is transmitted and received bidirectionally via the transmission optical waveguide and the reception optical waveguide. A pair of optical transmission / reception units, and each of the pair of optical transmission / reception units includes a light-emitting element and a light-receiving element, a submount manufactured by an electroforming process, and ends of the transmission optical waveguide and the reception optical waveguide. An end of the polymer optical waveguide film is placed on the submount, and the light emitted from the light emitting element passes through the optical path at the reflection surface. The light emitting element is arranged so that it is converted and incident on the transmitting optical waveguide, and the light receiving element is arranged so that light from the receiving optical waveguide is received by the light path being converted by the reflecting surface. To do In the optical transceiver module according to symptoms.

[3] In the invention described in [1] or [2] above, the polymer optical waveguide film has a thickness of 50 μm to 200 μm.

[4] In the invention according to any one of [1] to [3], the polymer optical waveguide film is a transparent resin film having flexibility with an allowable bending radius of 3 mm or less. It is said.

[5] In the invention according to any one of [1] to [4], the clad portion surrounding the core portion of the optical waveguide has a norbornene structure in the main chain and a polar group in the side chain. It is characterized by comprising an alicyclic olefin resin.

[6] In the invention according to any one of [1] to [5], a film surface of the polymer optical waveguide film is bonded to a main surface of the submount.

[7] In the invention according to any one of [1] to [6], the core portion of the optical waveguide is duplicated using a silicone resin mold.

[8] In the invention described in [1] or [2], the reflection surface is a 45-degree mirror surface that bends the light traveling direction by 90 degrees.

[9] In the invention described in [1] or [2] above, an electrode pattern for electric wiring is formed on the submount.

[10] In the invention described in [1] or [2] above, the light emitting element and the light receiving element are fixed on the submount through the same resin as a resin constituting a core portion of the optical waveguide. It is characterized by.

  The present invention can efficiently and stably dissipate heat generated from the light-emitting element, and can reliably prevent deterioration of the characteristics and life of the light-emitting element. Since a flexible belt-shaped polymer optical waveguide film that can follow the deformation of the film is used, the optical signal can be transmitted through the optical waveguide formed in the polymer optical waveguide film even when the film is deformed. Can send and receive.

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

(Configuration of optical transceiver module)
FIG. 1 is a perspective view schematically showing a configuration example of a bidirectional optical transceiver module according to a typical embodiment of the present invention. In this embodiment, a bidirectional optical transceiver module is described as an example. However, the present invention is not limited to this, and can be used for, for example, a unidirectional optical transceiver module. It is.

  In the same figure, the code | symbol 10 has shown the external appearance structure of the bidirectional | two-way optical transmission / reception module. As shown in FIG. 1, the basic configuration of the bidirectional optical transceiver module 10 includes a belt-shaped polymer optical waveguide film 11, a transmission optical waveguide formed in the polymer optical waveguide film 11, and a receiver. The first and second optical transmission / reception units 20 and 21 transmit and receive optical signals bidirectionally via the optical waveguide. Each of the optical transceivers 20 and 21 includes a surface-emitting type semiconductor laser diode (LD) 22 that is a light-emitting element, a photodiode (PD) 23 that is a light-receiving element, and a metal optical component mounting first. A submount 24 or a second submount 25 is provided, and both ends of the polymer optical waveguide film 11 are held on the submounts 24 and 25, respectively.

(Polymer optical waveguide film)
As shown in FIG. 1, the polymer optical waveguide film 11 is made of a transparent resin film material having a flexible bending radius of 3 mm or less, and has a followability to deformation such as bending and twisting. . With this configuration, even when the polymer optical waveguide film 11 is deformed, the optical signal transmitted from the LD 22 of the first optical transmission / reception unit 20 is guided through the optical waveguide of the polymer optical waveguide film 11, so that the second Can be received by the PD 23 of the optical transceiver 21.

  The polymer optical waveguide film 11 is preferably set to a thickness of 50 μm to 300 μm, and more preferably 70 μm to 200 μm, in order to improve followability to deformation. For the same reason, the film width is preferably set in the range of 0.5 mm to 10 mm, and more preferably in the range of 1 mm to 5 mm.

  FIG. 2 schematically shows a configuration example of the end portion of the polymer optical waveguide film. 2A is a partial cross-sectional view of the polymer optical waveguide film before dicing, and FIG. 2B is a partial cross-sectional view of the polymer optical waveguide film after dicing.

  As shown in FIG. 2, the polymer optical waveguide film 11 includes a mouth-shaped core portion 12 extending in the film length direction, and a clad portion 13 surrounding the core portion 12. In the polymer optical waveguide film 11, a plurality of core portions 12 are arranged in parallel in the film width direction, and a plurality of optical waveguides 14 are formed in the film. Although the present invention is not particularly limited, two optical waveguides 14 are formed in the film corresponding to the LD 22 and the PD 23.

  The polymer optical waveguide film 11 has the same structure on both sides in the film length direction. At one end of the polymer optical waveguide film 11, a first reflecting surface (mirror surface) 15 inclined at 45 degrees with respect to the optical axis of the optical waveguide 14 is provided in the film width direction, as shown in FIG. Is formed over. At the other end of the optical waveguide 14, a second mirror surface 15 of 45 degrees inclined downward in a direction different from the first mirror surface 15 is formed across the film width direction. The mirror surface 15 can be diced so that a submount abutting surface 16 comprising a vertical surface orthogonal to the lower surface of the film is formed. The mirror surface 15 functions as an optical path conversion surface that converts the optical path of incident light.

(Optical transceiver with submount)
FIG. 3 schematically illustrates a configuration example of an optical transmission / reception unit including a submount. Fig.3 (a) is a top view of an optical transmission / reception part, FIG.3 (b) is a fragmentary sectional view of the III-III line | wire of Fig.3 (a). As shown in FIG. 1, the first and second optical transmission / reception units 20 and 21 have the same structure on both sides except for the installation positions of the LD 22 and the PD 23. For this reason, in this Embodiment, only the 1st optical transmission / reception part 20 of one side is demonstrated.

  As shown in FIG. 3, the feature of the submount 24 is that it is constituted by a metal substrate made of a substantially rectangular parallelepiped in which metal layers are uniformly laminated by electroforming. The submount 24 can be manufactured using a general electroforming process. As an example, for example, an electro fine forming method which is a kind of ultra-precision etching method can be cited. According to this configuration, it is not necessary to attach a metal heat sink to the lower surface of the member on which the LD 22 is mounted, and heat generated from the LD 22 can be efficiently released to the outside. For this reason, power consumption can be suppressed and light emission with high luminance is possible.

  As shown in FIG. 3, the basic structure of the metal submount 24 includes a film mounting surface 24a on which the end of the polymer optical waveguide film 11 is mounted, and an element mounting on which the LD 22 and the PD 23 are mounted. A placement surface 24b and an electrode formation surface 24c on which an electrode film is formed are provided. The film mounting surface 24a and the element mounting surface 24b of the submount 24 can be formed, for example, by cutting the surface of the metal substrate of the submount 24.

  Although the present invention is not particularly limited, the film mounting surface 24a has a recessed shape formed as low as the thickness of the polymer optical waveguide film 11 from the main surface of the electrode forming surface 24c downward. There is no. The film front surface side of the recess that forms the film mounting surface 24a is formed with an engagement step portion 24d having a support surface inward from the side surface in the film width direction. The waveguide film 11 is brought into contact with the submount abutting surface 16. Thereby, the alignment of the film with respect to the submount 24 is facilitated, and the polymer optical waveguide film 11 can be easily mounted. One element mounting surface 24b has a concave shape opened in a direction intersecting with each other, and is lower than the film mounting surface 24a so that the lower end surface of the polymer optical waveguide film 11 is joined to the upper surfaces of the LD 22 and the PD 23. It is formed low. The concave portion forming the element mounting surface 24b has a space immediately below the 45-degree mirror surface 15 of the polymer optical waveguide film 11, and coincides with the peripheral surface of the space of the film mounting surface 24a.

  As shown in FIG. 3, each of the LD 22 and the PD 23 has a light-emitting surface and a light-receiving surface facing the lower side of the 45-degree mirror surface 15 of the polymer optical waveguide film 11, and a film mounted on the submount 24 via an adhesive. It is fixed on the mounting surface 24a. As the adhesive, a photocurable adhesive such as an ultraviolet curable resin, a thermosetting adhesive, or the like can be used. In order to reduce light loss, the core portion of the polymer optical waveguide film 11 is used. It is advantageous to use a material having the same refractive index as 12. By using a material having the same refractive index as that of the core portion 12, the divergence angle of the LD 22 and the PD 23 is reduced, and can be effectively mounted on the submount 24.

  The bidirectional optical transceiver module 10 controls, for example, the thickness of the polymer optical waveguide film 11 so that light emitted from the light emitting surface of the LD 22 is 45 degrees of the optical waveguide 14 for transmission without using a microlens. Light reflected by the mirror surface 15 and incident on the core portion 12 and guided in the core portion 12 of the receiving optical waveguide 14 is reflected by the 45 ° mirror surface 15 and received by the light receiving surface of the PD 23. By aligning and mounting, it can be assembled easily.

  Next, the mounting of the optical transceivers 20 and 21 will be described with reference to FIG. FIG. 4 is a plan view schematically showing one implementation example of the optical transmission / reception unit including the submount. Even in the illustrated example, the second optical transmission / reception unit 21 is not illustrated. In FIG. 4, members that are substantially the same as those in the illustrated example are given the same member names and symbols. Therefore, the detailed description regarding these members is omitted.

  When the bidirectional optical transceiver module 10 is mounted, as shown in FIG. 4, the LD 22, the PD 23, and the polymer optical waveguide film 11 are held on the submount 24 manufactured by an electroforming process. By holding the polymer optical waveguide film 11 on the film mounting surface 24a of the submount 24, the flexible polymer optical waveguide film 11 can be stably held.

  Further, in the bidirectional optical transceiver module 10, the submount 24 is fixed on the mounting surface of the ceramic substrate 30 as shown in FIG. 4. Although the present invention is not particularly limited, the upper surface of the ceramic substrate 30 is, for example, plated with gold having good thermal conductivity. The ceramic substrate 30 has two electrode pads 31 wired to the cathode and anode electrodes of the LD 22, a photodiode amplifier 32 electrically connected to the cathode and anode electrodes of the PD 23, and an electrical connection to the amplifier 32. Three electrode pads 33 are mounted. In the illustrated example, the submount 24 does not require patterning. It should be noted that electrodes for electrical wiring to the LD 22 and the PD 23 can be provided on the surface of the submount 24. When the bidirectional optical transceiver module 10 is stored in a package, the degree of freedom of electrical wiring with respect to the LD 22 and the PD 23 can be improved.

  According to the above configuration, the heat generated from the LD 22 is effectively dissipated by the submount 24, so that the device temperature rises and affects the characteristics of the LD 22, thereby preventing degradation of characteristics such as noise and variations. can do. In addition, since the optical transceiver 20 and the ceramic substrate 30 are mounted in a non-contact state, the heat generated in the LD 22 does not propagate to the ceramic substrate 30 side. As a result, the influence on the ceramic substrate 30 can be minimized, and heat can be stably radiated by the submount 24. In addition, heat generated during operation of the amplifier 32 can be enhanced by the cooperation of the submount 24 and the ceramic substrate 30. Therefore, the noise characteristics and reliability of the bidirectional optical transceiver module 10 can be improved.

(Operation of bidirectional optical transceiver module)
In the bidirectional optical transceiver module 10 configured as described above, the first optical transceiver 20 provided at one end of the polymer optical waveguide film 11 is provided at the other end of the polymer optical waveguide film 11. When an optical signal is transmitted to the second optical transceiver 21, the light emitted from the light emitting surface of the LD 22 held on the submount 24 of the first optical transceiver 20 passes through the clad 13 to a 45-degree mirror surface ( Incident light is incident from directly below (incident end face) 15. The light is reflected by the 45 ° mirror surface 15, undergoes an optical path change of 90 °, and is guided in the core portion 12 of the transmission optical waveguide 14. The light is converted into a vertical waveguide direction at a 45-degree mirror surface (outgoing end face) 15 of the transmission optical waveguide 14 on the second optical transmission / reception unit 21 side, and the sub-wave of the second optical transmission / reception unit 21 passes through the clad 13. The light is received by the light receiving portion of the PD 23 held by the mount 25.

  When the optical signal transmitted from the second optical transceiver 21 is received by the first optical transceiver 20, the light emitted from the light emitting surface of the LD 22 in the second optical transceiver 21 passes through the cladding 13. The light enters from directly below the mirror surface (incident end face) 15 of 45 degrees. The light is reflected by the 45 ° mirror surface 15, undergoes an optical path change of 90 °, and is guided in the core portion 12 of the receiving optical waveguide 14. The light is converted into a vertical propagation direction on the 45-degree mirror surface (outgoing end face) 15 of the receiving optical waveguide 14 on the first optical transmitting / receiving unit 20 side, and is received by the light receiving unit of the PD 24 through the clad 13. Become.

  In the optical transmission / reception module 10 according to the present embodiment, as described above, bidirectional optical communication is performed between the pair of optical transmission / reception units 20 and 21, but a flexible belt-like polymer optical waveguide film 11 is provided. Has followability to deformation such as bending and twisting, so that optical signals can be transmitted and received through the optical waveguide 14 formed in the polymer optical waveguide film 11 even when the film is deformed. Can do. Therefore, it can be effectively used for optical wiring of mobile devices such as mobile phones and thin personal computers that are often folded.

(Other module configuration)
In the above embodiment, the bidirectional optical transceiver module 10 that performs bidirectional optical communication between the optical transceivers 20 and 21 in which both the LD 22 and the PD 23 are mounted has been described. However, the present invention is not particularly limited. Alternatively, for example, a one-way optical transmission / reception module that performs one-way optical communication between an optical transmission unit including the LD 22 and an optical reception unit including the PD 23 may be used. Further, as the LD 22 and PD 23, flip-chip elements that are electrically connected to the electrode film by, for example, bumps may be used. By using a flip chip type element, it is not necessary to perform wire bonding, and the mounting becomes simple. Thereby, a module excellent in mass productivity can be provided.

(Production method of polymer optical waveguide film)
The polymer optical waveguide film 11 can be efficiently produced by the following steps (1) to (6).
(1) A mold formed from a cured layer of a mold-forming curable resin, provided with a concave portion corresponding to the core convex portion of the optical waveguide, and two or more through holes communicating with one end and the other end of the concave portion, respectively. Step of preparing (2) Step of bringing a flexible film substrate for clad having good adhesion to the mold into contact with the mold (3) Recess of the mold in which the flexible film substrate for clad is stuck Filling a through hole at one end of the core with a curable resin for core formation, and vacuum suction from the through hole at the other end of the concave portion of the mold to fill the concave portion of the mold with the core forming curable resin (4) Step of curing the filled core-forming curable resin and peeling the mold from the clad flexible film substrate (5) Step of forming a clad layer on the clad flexible film substrate with the core formed (6) Polymer optical waveguide fiber by dicing Forming an end face of Lum

  Each of these steps (1) to (6) is effective by a manufacturing method substantially the same as the manufacturing technique of the polymer optical waveguide and the like described in Patent Documents 1 to 3 previously proposed by the present applicants. Can get to.

  Optical elements manufactured from polymer optical waveguides can be used for optical wiring in various levels. The material of the flexible film base material for the clad considers optical properties such as refractive index and light transmittance, mechanical strength, heat resistance, adhesion to the mold, and flexibility depending on the use of the optical element. To be selected. Examples of the film include an alicyclic acrylic resin film, an alicyclic olefin resin film, a cellulose triacetate film, an epoxy resin film, and a fluorine-containing resin film. Further, the thickness of the film substrate is appropriately selected in consideration of flexibility, rigidity, ease of handling, and the like, and generally about 0.02 mm to 0.1 mm is preferable.

  As the core-forming curable resin, resins such as radiation curable, electron beam curable, and thermosetting can be used. Of these, ultraviolet curable resins and thermosetting resins are preferred. As the ultraviolet curable resin or thermosetting resin for forming the core, for example, an ultraviolet curable or thermosetting monomer, an oligomer, or a mixture of a monomer and an oligomer is preferably used. Moreover, as an ultraviolet curable resin, an epoxy type, a polyimide type, and acrylic type ultraviolet curable resin are used preferably, for example.

  The refractive index of the cured product of the core-forming curable resin needs to be larger than the film base material to be the clad, and the difference in refractive index between the clad and the core is 0.01 or more, preferably 0.03 or more. is there.

  As the curable resin for cladding, for example, an ultraviolet curable resin or a thermosetting resin is preferably used, and an ultraviolet curable or thermosetting monomer, an oligomer, or a mixture of a monomer and an oligomer is used. In addition, it is preferable from the viewpoint of light confinement that the refractive index of the clad be the same as that of the film substrate.

  According to the method for producing a polymer optical waveguide film, the production process is greatly simplified, and the polymer optical waveguide film can be easily produced. Therefore, it becomes possible to produce a polymer optical waveguide film at a very low cost as compared with the conventional method for producing a polymer optical waveguide film. Furthermore, although it is a simple method, the waveguide loss of the obtained polymer optical waveguide film is reduced, is highly accurate, and can be freely loaded into various devices.

  Hereinafter, more specific examples of the present embodiment will be described.

(Production of polymer optical waveguide film)
After applying a thick film resist (SU-8, manufactured by Micro Chemical Co., Ltd.) to a Si substrate by spin coating, pre-baking at 80 ° C., exposing through a photomask, developing, and forming a square cross section Convex portions (width: 50 μm, height: 50 μm, length: 80 mm) were formed. The interval between the protrusions was 250 μm. Next, this was post-baked at 120 ° C. to prepare a master for preparing a polymer optical waveguide.

  Next, after applying a release agent to the master, a thermosetting liquid dimethylsiloxane rubber (manufactured by Dow Corning Asia Co., Ltd .: SYLGARD 184, viscosity 5000 mPa.s) and a mixture of the curing agent are poured, and 120 ° C. After being cured by heating for 30 minutes, it was peeled off to produce a mold having a concave portion corresponding to a convex portion having a rectangular cross section (mold thickness: 5 mm).

  Further, a mold was produced by punching through-holes having a tapered cross-sectional shape in the thickness direction in a mold having a circular planar shape so as to communicate with the recess at one end and the other end of the recess.

This mold and a clad film substrate (Arton film, manufactured by JSR Corporation, refractive index 1.510) having a film thickness of 50 μm, which is slightly larger than the mold, were brought into close contact with each other. Next, the viscosity is 500 mPa.s in the entrance side through hole of the mold. When a few drops of the ultraviolet curable resin of s were dropped and sucked under reduced pressure from the discharge side (vacuum suction side) through-hole, the ultraviolet curable resin was filled in the recess in 10 minutes. Next, 50 mW / cm ² of UV light was irradiated from the upper part of the mold for 5 minutes to be cured by ultraviolet rays. When the mold was peeled off from the Arton film, a core having the same shape as the master disc protrusion was formed on the Arton film.

Next, an ultraviolet curable resin having a refractive index after curing of 1.510, which is the same as that of the ARTON film, is applied to the core forming surface of the ARTON film, and then a 50 μm clad film base material is laminated to obtain a 50 mW / cm ² By irradiating with UV light for 5 minutes and curing with ultraviolet light, the two films were bonded to form a belt-shaped polymer optical waveguide film having a width of 1.5 mm and a film thickness of 150 μm.

  Next, using a dicing saw equipped with a 45 ° angled blade, both ends of the polymer waveguide film were cut at an angle of 45 ° with respect to the optical axis, and a high angle mirror with 45 ° mirror surfaces at both ends. A molecular optical waveguide film was obtained.

(Production of submount)
A Ni submount having a thickness of 450 μm was formed using an electroforming process.

(Module implementation)
Each of both ends of the polymer optical waveguide film was aligned and then placed on a different Ni submount placement surface and fixed to the submount using an ultraviolet curable resin for the core portion.

  Next, the cathode and anode electrodes of the flip-chip type VCSEL device and the electrode pads on the Si submount are each flip-chip bonded, and the cathode and anode electrodes of the photodiode device and the electrodes on the Si submount. Flip chip bonding was performed between each pad. Thereby, the VCSEL element and the photodiode element were electrically connected to the electrode pad, and a bidirectional optical transmission / reception module including a pair of optical transmission / reception units and a polymer optical waveguide film was obtained.

(Evaluation of communication performance)
When the performance of optical transmission / reception was evaluated using a sampling oscilloscope (Agilent Technology: Agilent 86100C) and a pulse pattern generator, a good eye pattern up to 3.125 Gbps could be measured.

(Production of polymer optical waveguide film)
Similarly to Example 1, the end face of the waveguide was cut using a dicing saw equipped with a blade with a 45-degree angle to produce a waveguide film with a 45-degree mirror.

(Production of submount)
A Ni submount was produced in the same manner as in Example 1 above.

(Module implementation)
After embedding the VCSEL element and the photodiode element on the Ni submount, the electrodes of the light receiving and emitting elements were electrically connected by bonding to the package using Au wires. Next, after aligning each end of the polymer optical waveguide film, place it on the mounting surface of a different Ni submount, and fix it to the submount using the UV curable resin for the core did. Thus, a bidirectional optical transmission / reception module including a pair of optical transmission / reception units and a polymer optical waveguide film was obtained.

(Evaluation of communication performance)
The performance of optical transmission and reception was evaluated using a sampling oscilloscope (Agilent Technology: Agilent 86100C) and a pulse pattern generator, and a good eye pattern could be measured up to 3.125 Gbps.

  The optical transmission / reception module according to the present invention is not limited to the above-described embodiments, examples, and illustrated examples, and various design changes can be made without departing from the spirit of the invention.

It is a perspective view which shows typically one structural example of the bidirectional | two-way optical transmission / reception module which is typical embodiment in this invention. It is a fragmentary sectional view which shows typically one structural example of the edge part of the polymer optical waveguide film applied to the bidirectional | two-way optical transmission / reception module of this invention. It is the top view and sectional drawing which show typically one structural example of the optical transmission / reception part provided with the submount applied to the bidirectional | two-way optical transmission / reception module of this invention. It is a top view which shows typically the example of 1 mounting of the optical transmission / reception part provided with the submount applied to the bidirectional | two-way optical transmission / reception module of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Bidirectional optical transmission / reception module 11 Polymer optical waveguide film 12 Core part 13 Cladding part 14 Optical waveguide 15 Reflecting surface 16 Submount abutting surface 20, 21 1st, 2nd optical transmission / reception part 22 Light emitting element 23 Light receiving element 24, 25 First and second submounts 24a Film placement surface 24b Element placement surface 24c Electrode formation surface 24d Engagement step portion 30 Ceramic substrate 31, 33 Electrode pad 32 Amplifier

Claims (10)

A polymer optical waveguide film in which an optical waveguide is formed;
A light-emitting element; a first submount manufactured by an electroforming process; and a first reflecting surface for optical path conversion provided at one end of the optical waveguide, wherein the polymer optical light is disposed on the first submount. A structure in which one end portion of the waveguide film is placed and the light emitting element is arranged so that light emitted from the light emitting element is converted into an optical path by the first reflecting surface and is incident on the optical waveguide. An optical transmitter;
A light receiving element; a second submount manufactured by an electroforming process; and a second reflecting surface for optical path conversion provided at the other end of the optical waveguide, and the polymer on the second submount. An optical receiver having a configuration in which the other end portion of the optical waveguide film is placed and the light receiving element is disposed so that light from the light transmitting portion is received by the light path being converted by the second reflecting surface; An optical transmission / reception module comprising: A polymer optical waveguide film in which a transmission optical waveguide and a reception optical waveguide are formed;
A pair of optical transceivers that transmit and receive optical signals bidirectionally through the transmission optical waveguide and the reception optical waveguide;
Each of the pair of optical transmission / reception units includes a light emitting element and a light receiving element, a submount manufactured by an electroforming process, and a reflection for optical path conversion provided at an end of the transmission optical waveguide and the reception optical waveguide. And an end portion of the polymer optical waveguide film is placed on the submount, and light emitted from the light emitting element is converted in an optical path by the reflecting surface to the transmitting optical waveguide. Light comprising: the light emitting element disposed so as to be incident; and the light receiving element disposed such that light from the receiving optical waveguide is received by the light path being converted by the reflecting surface. Transmit / receive module.   3. The optical transceiver module according to claim 1, wherein the polymer optical waveguide film has a thickness of 50 μm to 200 μm.   4. The optical transceiver module according to claim 1, wherein the polymer optical waveguide film is a flexible transparent resin film having an allowable bending radius of 3 mm or less. 5.   5. The clad portion surrounding the core portion of the optical waveguide is made of an alicyclic olefin resin having a norbornene structure in the main chain and a polar group in the side chain. The optical transceiver module described in 1.   The optical transceiver module according to claim 1, wherein a film surface of the polymer optical waveguide film is bonded to a main surface of the submount.   The optical transmission / reception module according to claim 1, wherein the core portion of the optical waveguide is replicated using a mold made of silicone resin.   The optical transmission / reception module according to claim 1, wherein the reflection surface is a 45-degree mirror surface that bends the light traveling direction by 90 degrees.   3. The optical transceiver module according to claim 1, wherein an electrode pattern for electric wiring is formed on the submount.   3. The optical transceiver module according to claim 1, wherein the light emitting element and the light receiving element are fixed on the submount through the same resin as a resin constituting a core portion of the optical waveguide. .

Images