JP5078021B2 - Optical waveguide module and method for manufacturing optical waveguide module - Google Patents

Description

  The present invention relates to an optical waveguide module having a structure in which a circuit board on which an optical element which is a light receiving element or a light emitting element is mounted, and an optical waveguide for optical connection between the optical elements, and a manufacturing method thereof.

2. Description of the Related Art In recent years, for example, in view of demands for high-speed signal transmission in electronic devices and an increase in transmission amount, optical communication technology using a circuit board provided with an optical waveguide (hereinafter also referred to as an optical composite substrate) has been developed. Application to signal transmission is becoming widespread (for example, Patent Documents 1 and 2).
An optical composite substrate having a composite structure having an electronic circuit (conductor circuit) and an optical waveguide is often used, and the light receiving element and the light emitting element mounted on the optical composite substrate are optically connected via the optical waveguide. Thus, a module that can perform signal transmission between the light receiving element side and the light emitting element side (hereinafter also referred to as an optical waveguide module) is widely used.

The conventional optical waveguide module is provided with a mirror that bends the optical path of the optical waveguide at a right angle, as shown in FIG. 2 of Patent Document 1, FIG. 3D of Patent Document 2, and the like. A configuration in which optical coupling between an optical element (light receiving element or light emitting element) mounted above and an optical waveguide is realized is common.
JP 2000-199827 A JP 2002-182049 A

  However, the conventional optical waveguide module has a problem that it takes time to align the optical element with respect to the mirror. In addition, in the work of electrically connecting the optical element to the conductor circuit on the optical composite substrate, it is necessary to maintain the positioning accuracy of the optical element with respect to the mirror, which increases the labor for mounting the optical element. It was also.

An optical composite substrate has a structure in which an optical waveguide is provided on one side of a circuit substrate (single layer or multilayer) on which an electronic circuit (conductor circuit) is formed. A conventional optical waveguide module includes an optical element and an optical composite. Many structures have been proposed in which the substrate is mounted on the opposite side of the circuit board via the optical waveguide (Patent Documents 1 and 2 also correspond to this). The optical element is electrically connected to, for example, an LSI chip mounted on a circuit board or an integrated circuit formed by a multilayer circuit board.
In terms of increasing the speed of signal transmission and increasing the amount of transmission, there is a demand to shorten the wiring for electrically connecting the electronic circuit of the circuit board and the optical element as much as possible in order to ensure high-frequency signal characteristics. . However, as described above, in the structure in which the mounting position of the optical element with respect to the optical composite substrate is on the side opposite to the circuit board through the optical waveguide, the wiring must be provided so as to avoid the optical waveguide. Problems arise such that the structure of the composite substrate becomes complicated, the wiring length becomes long, and restrictions on the circuit design of the circuit substrate become large. For this reason, there has been a demand for the development of a technology that can shorten the wiring length, simplify the structure of the optical composite substrate, and can actually cope with the production level.

  In view of the above problems, the present invention can easily realize the positioning of the mirror portion of the optical waveguide substrate and the optical element and the mounting of the optical element on the circuit board, and between the electronic circuit of the circuit board and the optical element. An object of the present invention is to provide an optical waveguide module and a method for manufacturing the same, which can realize a reduction in wiring length and simplification of the structure of the optical waveguide substrate.

The present invention includes an optical waveguide substrate having a linear core portion in a plate-shaped cladding portion, and a circuit substrate attached to the optical waveguide substrate. The circuit substrate includes a light receiving element or a light emitting element. An optical element is housed and incorporated in an optical element housing hole penetrating the circuit board, and the optical element has a light receiving / emitting portion on an end surface facing the optical waveguide board, and the optical waveguide board Has a mirror part for forming an optical path between the optical waveguide of the optical waveguide substrate and the receiving / emitting part of the optical element at a position corresponding to the receiving / emitting part of the optical element, The circuit board includes a wiring portion formed on a bonding surface facing the optical waveguide substrate, a through-wiring that is provided in the circuit board and is electrically connected to the wiring portion, and the wiring portion extends from the wiring surface to the bonding surface. A protruding terminal projecting from the opening of the optical element housing hole And an electrode pad provided on the end face of the optical element is bonded to the terminal portion so as to be electrically conductive, and the electrode pad of the optical element and the terminal portion are for conductive bonding. Bonded with a metal material, the cross-sectional dimension of the optical element housing hole is perpendicular to the axis of the optical element housing hole in the optical element, and is 5 to 195% of the dimension of the contact surface of the electrode pad. The optical element storage hole and the cross-sectional shape of the optical element are rectangular, and the distance between the opposing inner surfaces of the optical element storage hole is a diagonal dimension of the cross-section of the optical element. less than, the optical device is in the optical element housing bore is rotatable movement set and regulated while the difference between the cross-sectional dimensions of the cross-sectional dimensions and the optical element of the optical element receiving hole, One in the entire range of rotational movement of the optical element around the axis direction around the axis of the optical element receiving hole, the contact surfaces of all the electrode pads of the optical element, respectively plane contact surface of the terminal portion Provided is an optical waveguide module having overlapping portions in view.
The present invention includes a filling resin portion that fills a space between the inner surface of the optical element housing hole and the optical element, and the end surface of the optical element is covered with a transparent resin layer continuous from the filling resin portion. Is preferred.
In the present invention, a transparent opening sealing member that seals an opening that opens to the bonding surface of the optical element housing hole is provided on a bonding surface of the circuit board facing the optical waveguide substrate. preferable.
In the present invention, an electrode pad and a metal bump mounted on the electrode pad are provided on the joint surface of the circuit board, and the metal bump is interposed through a bump housing hole penetrating the optical waveguide substrate. Preferably, the optical waveguide substrate protrudes from the side opposite to the circuit board.
In the present invention, it is preferable that the mirror portion of the optical waveguide substrate is constituted by a concave portion that is recessed from a side opposite to the circuit substrate of the optical waveguide substrate.
The present invention is a method of manufacturing the optical waveguide module, the semiconductor substrate, a wiring portion formed on one or both of the both sides of the semiconductor substrate, a through wiring penetrating the semiconductor substrate, An optical element housing hole into which an optical element that is a light receiving element or a light emitting element is a through-hole penetrating the semiconductor substrate, and from the wiring portion on one side of the semiconductor substrate to an opening at one end of the optical element housing hole The optical element is incorporated into the optical element accommodation hole of the substrate with the optical element accommodation hole provided with the protruding protrusion-shaped terminal portion, and is mounted in advance on an electrode pad provided on the optical element. An optical element mounting step of connecting the electrode pad to the terminal part by reflowing the metal bumps, and a linear core part in the plate-like clad part; The terminal of After the optical element mounting step, after the optical element mounting step, the optical waveguide of the optical waveguide substrate and the optical waveguide substrate of the optical element There is provided a method for manufacturing an optical waveguide module comprising a mirror part forming step of forming a mirror part for forming an optical path between a light receiving / emitting part provided on an end face facing each other.
The optical waveguide module manufacturing method of the present invention includes a filling resin portion forming step of forming a filling resin portion that fills a space between the inner surface of the optical element housing hole and the optical element after connecting the electrode pad to the terminal portion. After performing, it is preferable to perform a mirror part formation process.
In the method of manufacturing an optical waveguide module according to the present invention, in the filling resin portion forming step, the opening portion of the substrate with the optical element accommodation hole provided with the terminal portion of the optical element accommodation hole is sealed with the opening portion. It is preferable to form the filling resin portion by injecting a liquid resin material into the optical element housing hole in a state where the member is closed.
In the method for manufacturing an optical waveguide module of the present invention, it is preferable that a transparent resin layer covering the end face of the optical element is formed continuously from the filled resin portion in the filled resin portion forming step.
In the method for manufacturing an optical waveguide module of the present invention, after the filling resin portion forming step is completed, the opening sealing member is removed from the substrate with an optical element accommodation hole, and then the optical waveguide is attached to the substrate with an optical element accommodation hole. It is preferable to perform the mirror part forming step after depositing the substrate.
The method for manufacturing an optical waveguide module according to the present invention uses a transparent opening sealing member, and after the filling resin portion forming step is completed, the substrate with the optical element housing hole remains attached with the opening sealing member. It is preferable that the mirror part forming step is performed after the optical waveguide substrate is attached.
In the method of manufacturing an optical waveguide module according to the present invention, it is preferable that the filling resin portion forming step is performed using the optical waveguide substrate attached to the substrate with the optical element accommodation hole as the opening sealing member.

According to the present invention, the optical element is housed in the optical element housing hole of the circuit board and is mounted and mounted on the circuit board, and the optical element housing hole functions as a positioning portion for positioning the optical element. Can do. For this reason, the positioning of the mirror part of the optical waveguide substrate and the optical element and the mounting of the optical element on the circuit board can be easily realized.
Further, the configuration in which the optical element is incorporated into the circuit board can shorten the wiring length for electrically connecting the electronic circuit of the circuit board and the optical element. Thereby, it becomes easy to ensure high-frequency signal characteristics, and it is possible to increase the speed of signal transmission and increase the transmission amount.
Further, according to the present invention, it is not necessary to provide a wiring for electrically connecting the electronic circuit of the circuit board and the optical element so as to avoid the optical waveguide. Can be simplified. Thereby, the improvement of the manufacturing efficiency of an optical waveguide module and cost reduction are realizable.

Hereinafter, an optical waveguide module embodying the present invention and a method for manufacturing the optical waveguide module will be described with reference to the drawings.
FIG. 1 is a front sectional view showing the structure of an optical waveguide module 1 of the present embodiment, and FIG. 2 shows a state (electronic waveguide module 1A with a device) in which an electronic device 5 (LSI) is mounted on the optical waveguide module 1 of FIG. FIG. 3 is an enlarged cross-sectional view showing an enlarged area A indicated by a virtual line of the optical waveguide module 1 in FIGS. 1 and 2, and light formed on the circuit board 3 of the optical waveguide module 1. FIG. 4 is a diagram showing the structure of the element housing hole 31 and the vicinity of the optical element 4 incorporated in the optical element housing hole 31, and FIG. 4 shows the circuit board 3 and the optical element 4 before the optical element 4 is assembled in the optical element housing hole 31. It is a figure which shows the metal bump 45 mounted in the electrode pad 44. FIG.
1, 2, 3, and 4, for convenience of explanation, the upper side is described as “upper” and the lower side is described as “lower”. However, this is defined for convenience in order to simply explain the relative relationship of the constituent elements of the present invention, and does not limit the direction during production or use when the present invention is carried out.

As shown in FIGS. 1 and 2, the optical waveguide module 1 includes an optical waveguide substrate 2, a circuit substrate 3 attached to the optical waveguide substrate 2, and an optical element housing hole 31 formed in the circuit substrate 3. The optical element 4 is a light-emitting element or a light-receiving element that is incorporated and mounted therein.
2 shows an optical waveguide module with a device in which an electronic device 5 is mounted on the surface of the circuit board 3 of the optical waveguide module 1 opposite to the optical waveguide substrate 2 (hereinafter also referred to as a device mounting surface 3a). 1A is shown.
The circuit board 3 in which the optical element 4 is incorporated in the optical element housing hole 31 may be hereinafter referred to as an optical element built-in substrate (reference numeral 6 in the drawing). The optical element built-in substrate 6 is attached so as to overlap the optical waveguide substrate 2. The optical waveguide module 1 is a so-called composite substrate in which the optical element built-in substrate 6 and the optical waveguide substrate 2 are integrated.

The optical waveguide module 1 may have a configuration in which the circuit board 3 is provided on one surface of the optical waveguide substrate 2 and a sheet-like or plate-like base material is provided on the other surface. The base material may be, for example, a base material used when sequentially forming by applying a varnish containing a resin material for forming individual layers of an optical waveguide forming body having a three-layer structure described later.
This base material can function as, for example, a protective material or a reinforcing material for the optical waveguide substrate 2.

(Optical waveguide substrate)
The optical waveguide substrate 2 will be described.
FIG. 5 is a perspective view showing the structure of the optical waveguide substrate 2.
As shown in FIG. 5, the optical waveguide substrate 2 has a structure having a linear core portion 22 in a plate-like cladding portion 21. The periphery of the linear core portion 22 is covered with a clad portion 21.
The core part 22 does not need to be linear, and may be curved in the clad part 21. Moreover, the core part 22 may have a branch part, and thereby the core part 22 may be configured in a circuit shape.

As a manufacturing method of the optical waveguide substrate 2, for example, the following (a) and (b) can be adopted.
(A) As shown to Fig.6 (a), the clad layer 232 (resin layer for forming a part of clad part 21) is provided in both surfaces of the core layer 231 which is a resin layer for core part formation. An optical waveguide forming body 23 having a three-layer structure is prepared, and the optical waveguide forming body 23 is irradiated with active energy rays to form the core portion 22 (FIG. 6B).
By irradiation with active energy rays, a part of the core layer 231 becomes the core part 22, and a part other than the core part 22 of the core layer 231 and the clad layers 232 on both sides of the core layer 231 constitute the clad part 21.
In the case of this manufacturing method, the core part 22 having a quadrangular cross section (rectangle, but including a square) is obtained.

Examples of the material for forming the core layer 231 include resin materials such as acrylic resins, epoxy resins, polyimide resins, benzocyclobutene resins, and cyclic olefin resins such as norbornene resins. A resin composition mainly containing a cyclic olefin resin such as a benzocyclobutene resin or a norbornene resin is preferred, and a resin composition mainly containing an addition polymer of a norbornene resin is particularly preferred.
Examples of the active energy rays for forming the core portion 22 include active energy rays such as visible light, ultraviolet light, infrared light, and laser light, electron beams, and X-rays. An electron beam can be irradiated with an irradiation dose of, for example, about 50 to 200 KGy.
The material constituting the cladding layer is not particularly limited as long as the refractive index is lower than that of the material constituting the core layer. Specific examples include resin materials such as acrylic resins, epoxy resins, polyimide resins, benzocyclobutene resins, and cyclic olefin resins such as norbornene resins. Among these, a resin composition mainly comprising an addition polymer of norbornene resin is particularly preferable.
When a resin composition mainly composed of an addition polymer of norbornene-based resin is adopted as a material for forming the core layer and the clad layer, transparency, insulation, flexibility and heat resistance can be sufficiently obtained. In addition, the hygroscopicity can be reduced as compared with the case where other resins are used. In the case of a resin composition mainly composed of an addition polymer of norbornene resin, there is an advantage that the refractive index can be adjusted depending on the type of side chain of the addition polymer of norbornene resin.

The optical waveguide forming body 23 having a three-layer structure is formed by, for example, applying a varnish containing a resin material for forming individual layers of the optical waveguide forming body 23 to a sheet-like or plate-like base material. Can be obtained by sequentially forming. In this case, for example, the circuit board 3 itself can be used as a base material.
As the optical waveguide module 1, a circuit board 3 is formed on one surface of an optical waveguide substrate 2, and an optical waveguide forming body 23 having a three-layer structure is applied on the other surface by applying a varnish containing a resin material forming the individual layers. The structure provided with the base material used when forming may be sufficient.

(B) The periphery of the core part formed in advance is covered with a clad material (clad part).
In the case of this manufacturing method, the cross-sectional shape of the core part 22 becomes free.

The optical waveguide substrate 2 is disposed at a position corresponding to the light receiving / emitting section 401 (the light emitting section 411 of the light emitting element 41 or the light receiving section 421 of the light receiving element 42) of the optical element 4 of the optical element built-in substrate 6. The optical path (reference numeral H1 in FIG. 3) is bent at a right angle, and the optical path (reference numeral H2 in FIG. 3) between the optical waveguide substrate 2 and the optical element 4 (specifically, the light emitting section 411 or the light receiving section 421). ) To form a mirror portion 24.
The optical element 4 and the optical waveguide substrate 2 are optically coupled via a mirror part 24.
Specifically, the mirror part 24 is constituted by a recess formed in the optical waveguide substrate 2 so as to be recessed from the side opposite to the circuit board 3. The mirror portion 24 is formed so as to be interposed in the middle of the core portion 22 of the optical waveguide substrate 2.

  1 and 2 schematically show the formation positions of the mirror portions 24 at a plurality of locations on the optical waveguide substrate 2, and all the mirror portions 24 in the figure do not have a branching portion. It does not mean the structure formed about the core part 22 of. The aspect in which three or more mirror portions 24 are formed on the optical waveguide substrate 2 is realized by the optical waveguide substrate 2 having the core portion 22 having the branching portion or the optical waveguide substrate 2 having the plurality of core portions 22. The The mirror part 24 is provided for optically connecting the light emitting element 41 and the light receiving element 42 via the core part 22 of the optical waveguide substrate 2. It is set so that optical connection between the element 41 and the light receiving element 42 can be realized.

(Optical element built-in substrate)
Next, the optical element built-in substrate 6 will be described.
As described above, the optical element built-in substrate 6 is mounted by incorporating the optical element 4 in the optical element accommodation hole 31 formed in the circuit board 3.

As shown in FIGS. 1 to 4, the optical element housing hole 31 of the circuit board 3 penetrates the circuit board 3 and is opened on both surfaces of the circuit board 3, that is, joined to the optical waveguide substrate 2. It is a through-hole opened to the bonding surface 3b and the device mounting surface 3a.
The optical element housing holes 31 are formed at a plurality of locations on the circuit board 3.

In each optical element housing hole 31, a light emitting element 41 or a light receiving element 42 is incorporated as the optical element 4.
The light emitting element 41 is a semiconductor laser such as a VCSEL (Vertical Cavity Surface Emitting LASER). The light receiving element 42 is, for example, a PD (photodiode).

The illustrated example illustrates a configuration in which an optical element accommodation hole 31 in which a light emitting element 41 is incorporated and an optical element accommodation hole 31 in which a light receiving element 42 is incorporated exist in one circuit board 3.
Each optical element 4 is incorporated in the optical element housing hole 31 with the light emitting part 411 or the light receiving part 421 facing the optical waveguide substrate 2. In the optical element built-in substrate 6, the light receiving / emitting section 401 (the light emitting section 411 or the light receiving section 421) of each optical element 4 is provided at a position corresponding to the mirror section 24 of the optical waveguide substrate 2. The optical path H1 of the optical waveguide substrate 2 is optically coupled.
The optical waveguide module 1 includes a pair of a light emitting element 41 and a light receiving element 42 that are optically connected to each other via an optical waveguide substrate 2 (specifically, an optical path H1 of the optical waveguide substrate 2).

The light receiving / emitting section 401 (light emitting section 411 or light receiving section 421) of the optical element 4 is provided on an end face 43 (hereinafter also referred to as a receiving / light emitting section installation surface) facing the optical waveguide substrate 2 of the optical element 4. .
FIG. 7 shows the light receiving / emitting part installation surface 43 of the optical element 4.
As shown in FIG. 7, the light receiving / light emitting portion installation surface 43 of the optical element 4 is provided with a light receiving / light emitting portion 401 (light emitting portion 411 or light receiving portion 421) and an electrode pad 44. The light receiving / light emitting unit 401 is provided at the center of the light receiving / light emitting unit installation surface 43. The electrode pads 44 are provided at a plurality of locations around the light receiving / light emitting unit 401 on the light receiving / light emitting unit installation surface 43.
In the light emitting element 41, the electrode pad 44 functions as an input terminal for an electric signal for driving to the light emitting element 41. In the light emitting element 42, the electrode pad 44 functions as an output terminal for outputting a light receiving signal (electric signal) from the light receiving element 42.

Note that the position of the light receiving / light emitting unit 401 on the light receiving / light emitting unit installation surface 43 is not necessarily the center of the light receiving / light emitting unit installation surface 43. The position may be shifted from the center of the light receiving / light emitting unit installation surface 43.
Further, the number of light receiving / light emitting portions 401 provided on the light receiving / light emitting portion installation surface 43 is not limited to one, and may be plural (see FIGS. 14A to 14C as an example). ).

FIG. 8 is a plan view showing a relationship between the optical element accommodation hole 31 and the optical element 4 incorporated in the optical element accommodation hole 31 (a view showing a structure viewed from the device mounting surface 3a side of the circuit board 3). is there.
As shown in FIGS. 7 and 8, the optical element 4 is specifically a rectangular (appearance rectangular parallelepiped) chip-type electronic device. The optical element housing hole 31 has a square hole shape (specifically, in FIG. 8, a square through-hole in plan view). The optical element 4 is incorporated in the optical element accommodation hole 31 so that the light receiving / emitting part installation surface 43 is perpendicular to the axis 31 a of the optical element accommodation hole 31 of the circuit board 3.

  The circuit board 3 includes a wiring part 32 (conductor circuit) formed on the joint surface 3b, a through-wiring 33 penetrating through the circuit board 3 and connected to the wiring part 32 so as to be electrically conductive, and the wiring And a protruding terminal portion 34 projecting from the portion 32 to the opening of the optical element housing hole 31 in the joint surface 3b.

As shown in FIG. 3 and the like, the optical element 4 bonds the electrode pad 44 of the light receiving / emitting part installation surface 43 to the terminal part 34 of the circuit board 3 with a conductive bonding metal material (bonding metal part 36). The circuit board 3 is incorporated and electrically connected to the wiring portion 32 of the circuit board 3. The electrode pads 44 of the optical element 4 and the terminal portions 34 of the circuit board 3 are connected so as to be electrically conductive by bonding. The bonding metal portion 36 is formed of a conductive bonding metal material.
Reference numeral 35 denotes a bonding gold metal portion in which an end portion of the through wiring 33 on the device mounting surface 3a side of the circuit board 3 and an electrode pad (not shown) of the electronic device 5 are bonded and electrically connected. The bonding metal portion 35 is formed of a conductive bonding metal material. Through the bonding, the through wiring 33 is electrically connected to the electronic circuit of the electronic device 5. For this reason, the optical element 4 electrically connected to the wiring portion 32 via the terminal portion 34 of the circuit board 3 is electrically connected to the electronic device 5 via the wiring portion 32 and the through wiring 33. The

  For example, solder can be used as the bonding metal material. In the case of solder, the bonding between the electrode pad 44 and the terminal portion 34 and the bonding between the through wiring 33 and the electrode pad of the electronic device 5 are soldering.

As shown in FIG. 4, the optical element 4 may be a flip chip type in which metal bumps 45 are mounted on electrode pads 44. In this case, the optical element 4 is inserted and accommodated in the optical element accommodation hole 31 from the device mounting surface 3 a side of the circuit board 3, and the metal bump 45 of the optical element 4 contacts the terminal portion 34 of the circuit board 3. In this state, by reflowing the metal bump 45 and cooling and solidifying, the electrode pad 44 of the optical element 4 can be bonded to the terminal portion 34 of the circuit board 3. In this case, the bonding metal portion 36 is formed by reflow of the metal bump 45 and cooling and solidification.
However, the method for realizing the bonding between the electrode pad 44 of the optical element 4 and the terminal portion 34 of the circuit board 3 is not limited to this, and for example, a metal bump installed on the terminal portion 34. It is also possible to realize by reflow.

Metal bumps for bonding the electrode pads 44 and the terminal portions 34 are formed of a bonding metal material.
As the metal material for bonding, for example, Au (gold), InAu alloy, and other low melting point alloys can be used in addition to solder. The metal material for bonding refers to a material made entirely of a conductive metal (including an alloy) or a material mainly composed of a metal (including an alloy; having conductivity). The latter contains a trace amount of additives such as flux.
As a bonding metal material that forms a metal bump for bonding the electrode pad 44 and the terminal portion 34, a material that can realize brazing between the electrode pad 44 and the terminal portion 34 is preferable.

As a metal material (bonding metal material) for bonding the through wiring 33 and the electrode pad of the electronic device 5, a material that can realize brazing between the through wiring 33 and the electrode pad of the electronic device 5 is preferable. A bonding metal material similar to the metal bump (bonding metal material) for bonding between and the terminal portion 34 can be employed.
Note that the metal bumps 62 and 63 (described later) in FIG. 1 may be made of a bonding metal material similar to the metal bump for bonding the electrode pad 44 and the terminal portion 34.

3 and 8, reference numeral 37 denotes a filling resin portion that fills a space between the inner surface (inner peripheral surface) of the optical element housing hole 31 and the optical element 4 (specifically, the outer peripheral surface of the optical element 4), and reference numeral 38. Is a transparent resin layer covering the light receiving / emitting part installation surface 43 of the optical element 4.
In FIG. 4, reference numeral 7 denotes an opening sealing member that adheres to the bonding surface 3 b of the circuit board 3 and closes the opening of the optical element housing hole 31 in the bonding surface 3 b of the circuit board 3. The opening sealing member 7 is formed in a sheet shape or a plate shape, and injects the liquid resin material 8 for forming the filling resin portion 37 and the transparent resin layer 38 into the optical element housing hole 31 (FIG. 12), the opening of the optical element housing hole 31 in the joint surface 3b of the circuit board 3 is closed to prevent leakage of the resin material 8 from the opening.

The optical element accommodation hole 31 of the circuit board 3 of the optical waveguide module 1 according to the present invention has a cross-sectional dimension (a dimension of a cross section perpendicular to the direction of the axis 31a (center axis)). Is also slightly larger than the cross-sectional dimension perpendicular to the axis 31a of the optical element housing hole 31 in the optical element 4 (hereinafter also referred to as the sectional dimension of the optical element 4) (contact of the electrode pad 44). The dimension is increased by 5 to 195% of the dimension of the surface 44a.
The relationship between the cross-sectional dimension of the optical element housing hole 31 and the contact surface 44a of the electrode pad 44 of the optical element 4 will be described in detail later.

The filled resin portion 37 has an entire circumference of the inner peripheral surface of the optical element accommodation hole 31 (however, any one or more of the apexes at the four corners of the cross section of the optical element 4 shown in FIG. Is formed over the contact area (excluding this contact portion) (see, for example, FIG. 9).
The filling resin portion 37 effectively contributes to prevention of positional deviation of the optical element 4 in the optical element accommodation hole 31.

The transparent resin layer 38 is formed continuously from the filling resin portion 37 and covers the light receiving / emitting portion installation surface 43 of the optical element 4. The transparent resin layer 38 transmits light transmitted between the mirror part 24 of the optical waveguide substrate 2 and the light receiving / emitting part 401 of the optical element 4. Transmission of an optical signal between the light receiving / emitting unit 401 of the optical element 4 and the optical waveguide substrate 2 is performed via the mirror unit 24 and the transparent resin layer 38.
In addition, the transparent resin layer 38 prevents an air layer from intervening between the light receiving / emitting part 401 of the optical element 4 and the optical waveguide substrate 2 (or the mirror part 24 and the optical element 4 (specifically, light emission). The portion of the light path H2 between the light receiving portion 411 and the light receiving portion 421) is effectively reduced and the loss is effectively reduced.

(Electronic device)
Next, the electronic device 5 will be described.
In FIG. 2, the electronic device 5 is mounted at a plurality of locations on the device mounting surface 3 a of the circuit board 3.
The electronic device 5 in the illustrated example is formed in a chip shape by laminating a plurality of substrates 51 on which electronic circuits are formed. The electronic device 5 includes an integrated circuit formed by electrically connecting electronic circuits 52 (conductor circuits) on a substrate 51. In FIG. 2, reference numeral 53 denotes a via wiring. Hereinafter, the electronic device 5 is also referred to as an LSI.
However, the electronic device mounted on the device mounting surface 3a of the circuit board 3 is not limited to an LSI, and may be, for example, a packaged IC chip, LSI chip, or the like.

  In the electronic device 5, an electrode pad (not shown) provided on the lower surface 5 a formed by the substrate 51 located at one end of the stacked substrate 51 among the stacked substrates 51 is connected to the through wiring 33 ( Alternatively, they are connected to an electronic circuit (conductor circuit) provided on the device mounting surface 3 a of the circuit board 3 so as to be electrically conductive and mounted on the device mounting surface 3 a of the circuit board 3.

  In the present embodiment, as shown in FIG. 4, the metal bumps 351 mounted on the device mounting surface 3 a of the circuit board 3 are electrically connected to the electrode pads of the electronic device 5 and the through wiring 33 of the circuit board 3. However, the present invention is not limited to this. For example, a metal bump mounted on the electrode pad of the electronic device 5 is connected to the electrode pad of the electronic device 5 and the wiring of the circuit board 3. It is also possible to use as a metal material for bonding for electrically connecting the two. The bonding metal portion 35 is formed by reflowing and cooling and solidifying the metal bump for bonding between the electrode pad of the electronic device 5 and the through wiring 33 of the circuit board 3.

  Note that an electronic circuit (conductor circuit) electrically connected to the through wiring 33 may be provided on the device mounting surface 3 a of the circuit board 3. In this case, the metal bump 62 for connecting the through wiring 33 and the circuit of the electronic device 5 is shifted from the end of the through wiring 33 on the device mounting surface 3a side to the electronic circuit on the device mounting surface 3a. It can also be provided.

The LSI 5 functions as a drive control circuit for the light emitting element 41 and / or an output signal amplifier for the light receiving element 42. The LSI 5 illustrated in FIG. 2 is electrically connected to the light emitting element 41 and the light receiving element 42 via the through wiring 33 and the wiring portion 32 of the circuit board 3, and the drive control circuit of the light emitting element 41 and the light receiving element It functions as an output signal amplifier of the element 42.
The LSI 5 mounted on the circuit board 3 may be configured to have only one function of the drive control circuit of the light emitting element 41 and the output signal amplifier of the light receiving element 42.

(Through wiring for electronic devices)
1 and 2, reference numeral 61 denotes a through wiring for an electronic device.
The through wiring 61 for electronic devices is provided in the circuit board 3 in the thickness direction (vertical direction in FIGS. 1 and 2), and the electronic device 5 mounted on the device mounting surface 3a of the circuit board 3; It can be used as a connection wiring for electrically connecting an electronic device 9 (for example, a circuit board, a semiconductor package, etc.) provided on the opposite side of the optical waveguide substrate 2 of the optical waveguide module 1 from the circuit board 3. .

As shown in FIG. 1, the optical waveguide module 1 includes metal bumps 62 for connecting the electronic device through wiring 61 and the electronic device 5 on the device mounting surface 3 a of the circuit board 3. A metal bump 63 for connecting the electronic device 9 and the electronic device through wiring 61 is provided on the bonding surface 3b.
The optical waveguide substrate 2 is provided with bump housing holes 25 for housing the metal bumps 63 on the bonding surface 3 b side, and the metal bumps 63 on the bonding surface 3 b side are stored in the bump housing holes 25. At the same time, the optical waveguide substrate 2 protrudes from the bump housing hole 25 on the side opposite to the circuit substrate 3.
Therefore, in this optical waveguide module 1, as shown in FIG. 2, the electronic device 5 connected to the electronic device through wiring 61 by the metal bump 62 and the electronic device 9 connected to the electronic device through wiring 61 by the metal bump 63. Can be electrically connected through the through-hole wiring 61 for electronic devices. The metal bumps 63 can be used as input / output terminals for electrical signals to the electronic device 5.

The wiring (including the through wiring 33, the wiring portion 32, the terminal portion 34, and the through wiring 61 for electronic devices) formed on the circuit board 3 of the optical waveguide module 1 is formed of a conductive metal such as copper or a copper alloy. Has been.
As the conductor metal, for example, gold, aluminum or the like can be used.
Further, the circuit board 3 can be provided with a diffusion preventing film for the purpose of preventing the conductor metal forming the wiring from diffusing (metal is transferred) into the semiconductor substrate 39. The diffusion prevention film is interposed between the conductor metal forming the wiring and the semiconductor substrate 39. Examples of the metal for the diffusion prevention film include Ta, TiN, SiN and the like.

According to the optical waveguide module 1 and the device-equipped optical waveguide module 1A, since the optical element 4 is incorporated in the optical element housing hole 31 of the circuit board 3, the electron mounted on the device mounting surface 3a of the circuit board 3 is used. The wiring for securing the electrical connection between the device 5 and the optical element 4 does not need to bypass the optical waveguide substrate 2, and the wiring length can be shortened. By shortening the wiring length, it becomes easy to ensure high-frequency signal characteristics, and it is possible to increase the speed of signal transmission and increase the transmission amount.
In addition, according to the present invention, it is not necessary to provide an optical waveguide so as to be avoided by shortening and simplifying the wiring for electrically connecting the electronic circuit of the circuit board and the optical element. The entire structure of the optical waveguide module can be simplified. Thereby, the improvement of the manufacturing efficiency and cost reduction of an optical waveguide module are also realizable.

(Production method)
Next, an example of a method for manufacturing the above-described optical waveguide module 1 will be described.
Here, as shown in FIG. 4, a case will be described in which an optical element 4 having a metal bump 45 mounted on an electrode pad 44 is used.

The circuit board 3 used here includes a wiring portion 32 formed on one or both sides of the semiconductor substrate 39 (a surface on at least the bonding surface 3b side of both sides) of the semiconductor substrate 39, and the semiconductor substrate 39 A through-wiring 33 penetrating through 39, an optical element housing hole 31, and a projecting terminal portion 34 projecting from the wiring portion 32 into the opening on the joint surface 3 b side of the optical element housing hole 31. Is provided (a substrate with an optical element accommodation hole).
In addition, the circuit board 3 has metal bumps 351 mounted on the device mounting surface 3 a for electrically connecting the electrode pads of the electronic device 5 and the through wiring 33 of the circuit board 3.

Here, the semiconductor substrate 39 is specifically a silicon substrate.
In FIG. 4 and the like, reference numeral 39a denotes an oxide film (silicon oxide film) formed on the surface of the semiconductor substrate 39. The wiring formed on the circuit board 3 such as the through wiring 33 and the wiring portion 32, and the semiconductor substrate 39 Ensure electrical insulation between.

In addition, here, the circuit board 3 is provided with an electronic device through wiring 61 and metal bumps 62 and 63. A bump housing hole 25 is formed in the optical waveguide substrate 2 provided in a state of being attached to the circuit substrate 3.
However, the metal bumps 63 on the bonding surface 3b side of the circuit board 3 may be mounted on the circuit board 3 after the bump housing holes 25 are formed in the optical waveguide board 2 that is attached to the circuit board 3. .

As a method for processing (forming) the bump housing holes 25 in the optical waveguide substrate 2, for example, laser processing using an excimer laser is suitable. In addition, a method using reactive ion etching (RIE), exposure of the optical waveguide substrate 2 having photosensitivity, processing by development, and the like can be employed.
In laser processing, the bump housing hole 25 having a desired size can be easily processed by using a stencil mask. In the exposure and development of the optical waveguide substrate 2 having reactive ion etching and photosensitivity, a bump housing hole 25 having a desired size can be easily processed by using a film-like mask or a resist resin.

(Optical element mounting process)
First, the optical element 4 is incorporated into the optical element housing hole 31 of the circuit board 3, and the metal bumps 45 mounted in advance on the electrode pads 44 of the optical element 4 are reflowed, so that the electrode pads 44 are Bonding to the terminal portion 34 of the circuit board 3 (optical element mounting step). By cooling and solidifying the reflowed metal bumps 45, the electrode pads 44 of the optical element 4 and the terminal portions 34 of the circuit board 3 are bonded.

  In the optical element mounting step, by reflowing the metal bumps 45, the contact surfaces 44 a of the plurality of electrode pads 44 of the optical element 4 and the circuit board 3 are caused by the surface tension of the molten bump material (bonding metal material). The contact surface 34a formed on each of the plurality of terminal portions 34 overlaps (overlap in plan view, the contact surfaces 44a and 34a in FIG. 9 overlap each other). The position is adjusted (self-alignment of the optical element 4 due to the surface tension of the molten bonding metal material itself).

As described above, in the optical waveguide module 1 according to the present invention, the cross-sectional dimension of the optical element housing hole 31 of the circuit board 3 is equal to the cross-sectional dimension of the optical element 4 and the dimension of the contact surface 44 a of the electrode pad 44. The size is increased by 5 to 195%. 8 and 9, specifically, the optical element 4 has a rectangular cross section perpendicular to the axis 31a (center axis) of the optical element housing hole 31 (typically square in FIGS. 8 and 9). The cross-sectional shape perpendicular to the axis 31a (center axis) of the optical element housing hole 31 is a similar shape (rectangle, more specifically, slightly larger than the cross-sectional shape of the optical element 4). Square).
At the stage where the optical element 4 is accommodated in the optical element accommodation hole 31 of the circuit board 3 (before the reflow of the metal bumps 45), the movable range in the optical element accommodation hole 31 is secured for the optical element 4.

The contact surfaces 44a of the plurality of electrode pads 44 of the optical element 4 of the illustrated example shown in FIG. 7 are rectangular (squares in the illustrated example), and their areas are aligned with each other. In addition, in the plurality of terminal portions 34 of the circuit board 3 in the illustrated example shown in FIG. 9, the contact surface 34 a has the same shape and area as the contact surface 44 a of the electrode pad 44 of the optical element 4. The optical element 4 is positioned so that the contact surfaces 44 a of all the electrode pads 44 are collectively overlapped with the contact surfaces 34 a of the plurality of terminal portions 34 of the circuit board 3 by adjusting the position in the optical element housing hole 31. Can be combined.
The cross-sectional dimension of the optical element housing hole 31 is obtained by adding 5 to 195% of the length of one of the four sides of the contact surface 44a of the electrode pad 44 of the optical element 4 to the cross-sectional dimension of the optical element 4. It has become.

  When the contact surface 44a of the electrode pad 44 of the optical element 4 is circular, the cross-sectional dimension of the optical element housing hole 31 is 5 to 195% of the diameter of the contact surface 44a of the electrode pad 44 of the optical element 4. The dimension is in addition to the cross-sectional dimension of the optical element 4.

  When the metal bump 45 is reflowed, the surface tension of the molten bump material (bonding metal material) itself causes contact surfaces 44a of the plurality of electrode pads 44 of the optical element 4 and the plurality of terminal portions 34 of the circuit board 3 to be formed. The position of the optical element 4 in the optical element accommodation hole 31 is adjusted so that the contact surface 34a overlaps. Here, when the metal bump 45 is reflowed, the overlap between the contact surfaces 44 a of the plurality of electrode pads 44 of the optical element 4 and the contact surfaces 34 a of the plurality of terminal portions 34 of the circuit board 3 is not necessarily limited to the optical element 4. The contact surfaces 44a of all the electrode pads 44 completely overlap the contact surfaces 34a of the plurality of terminal portions 34 of the circuit board 3 (the entire contact surfaces 44a of all the electrode pads 44 of the optical element 4 are the terminals 34). It is not necessary to be located on the contact surface 34 a, and there is a portion of the one or more electrode pads 44 of the optical element 4 where the contact surface 44 a is not located on the contact surface 34 a of the terminal portion 34 of the circuit board 3. You may do it.

The plurality of terminal portions 34 of the circuit board 3 do not have to have the shape, area, and installation interval of the contact surface 34a completely coincide with the contact surface 44a of the electrode pad 44 of the optical element 4, for example, the contact surface The size (area) of 34 a may be slightly larger or slightly smaller than the contact surface 44 a of the electrode pad 44 of the optical element 4.
Further, the shapes and areas of the contact surfaces 34a of the plurality of terminal portions 34 do not necessarily have to coincide with each other, and may vary slightly.

  By performing self-alignment of the optical element 4 by reflow of the metal bump 45, the position of the optical element 4 accommodated in the optical element accommodation hole 31 is adjusted, and the contact surfaces 44a of all the electrode pads 44 of the optical element 4 are It is possible to easily obtain a state in which the range overlapping the contact surfaces 34a of the plurality of terminal portions 34 of the circuit board 3 is sufficiently secured. For this reason, the bonding and electrical connection of each electrode pad 44 and the terminal portion 34 are ensured by cooling and solidifying the molten bump material.

In order to realize self-alignment of the optical element 4 by reflow of the metal bumps 45, before reflowing the metal bumps 45 of the optical element 4 accommodated in the optical element accommodation hole 31, all the electrode pads 44 of the optical element 4 are arranged. The metal bump 45 needs to be in contact with the terminal portion 34 of the circuit board 3. For this reason, the cross-sectional dimensions of the optical element accommodation holes 31 of the circuit board 3 are such that the contact surfaces 44a of all the electrode pads 44 of the optical elements 4 accommodated in the optical element accommodation holes 31 are contact surfaces of the terminal portions 34, respectively. It is adjusted so as to have a portion overlapping with 34a.
The contact surface of the electrode pad 44 has a cross-sectional dimension of the optical element housing hole 31 of the circuit board 3 that is perpendicular to the axial center 31 a (center axis) of the optical element housing hole 31 of the optical element 4. If the dimension is larger by 5 to 195% of the dimension of 44a, the contact surfaces 44a of all the electrode pads 44 of the optical element 4 accommodated in the optical element accommodating hole 31 are respectively contacted with the contact surfaces 34a of the terminal portion 34. The relationship of having overlapping parts can be realized.

As shown in FIG. 9, in order to smoothly realize the self-alignment of the optical element 4 due to the reflow of the metal bump 45, the optical element 4 accommodated in the optical element accommodation hole 31 is subjected to light when the metal bump 45 is reflowed. Allowed movement of the element housing hole 31 in a direction along a plane orthogonal to the axis 31a (center axis), rotational movement around the axis about the axis 31a, and tilting with respect to the axis 31a (see FIG. 10). Need to be.
In this regard, the position of the terminal portion 34 with respect to the optical element housing hole 31 is determined when the central portion of the contact surface 44a of all the electrode pads 44 of the optical element 4 overlaps the central portion of the contact surface 34a of the terminal portion 34 (contact When the area where the surfaces 44a and 34a overlap each other is the maximum, the state at this time is also referred to as a complete alignment state, and the cross section orthogonal to the outer periphery of the optical element 4 (the axis 31a of the optical element housing hole 31). The outer periphery of the optical element housing hole 31 is preferably set so as to ensure a gap over the entire circumference. In the present embodiment, a configuration in which this position setting is performed for the terminal portion 34 is illustrated.
However, the present invention is not limited to this, and the position setting of the terminal portion 34 can be appropriately changed.

  The difference between the cross-sectional dimension of the optical element housing hole 31 of the circuit board 3 and the cross-sectional dimension of the optical element 4 perpendicular to the axis 31a (center axis) of the optical element housing hole 31 is the electrode pad of the optical element 4 The gap between the inner peripheral surface of the optical element storage hole 31 and the outer peripheral surface of the optical element 4 stored in the optical element storage hole 31 is too small if it is less than 5% of the dimension of the contact surface 44a of 44, The possibility that the self-alignment of the optical element 4 due to the reflow of the metal bumps 45 will not be realized smoothly increases. Further, it takes time to insert the optical element 4 into the optical element housing hole 31.

  On the other hand, the difference between the cross-sectional dimension of the optical element housing hole 31 of the circuit board 3 and the cross-sectional dimension of the optical element 4 perpendicular to the axis 31a (center axis) of the optical element housing hole 31 is If it exceeds 195% of the dimension of the contact surface 44 a of the electrode pad 44, the overlap between the contact surface 44 a of the electrode pad 44 of the optical element 4 accommodated in the optical element accommodation hole 31 and the contact surface 34 a of the terminal portion 34 will occur. When the metal bump 45 is reflowed, the case where the self-alignment due to the surface tension of the melted bump material (bonding metal material) is not effective is likely to occur. In this case, 195/2% of the dimension of the contact surface 44a of the electrode pad 44 of the optical element 4 between the outer periphery of the optical element 4 and the inner surface of the optical element housing hole 31 when the complete alignment state described above is achieved. A gap of a size of will be secured.

  As shown in FIG. 9, the cross-sectional dimension of the optical element storage hole 31 having a rectangular cross section (square in the illustrated example) of the circuit board 3 is such that the length of one side of the four cross sections is the optical element storage of the optical element 4. It must be smaller than the diagonal dimension of the cross section (cross-sectional shape is rectangular, square in the illustrated example) perpendicular to the axial center 31a (center axis) of the hole 31.

  If the length of one side of the optical element accommodation hole 31 is larger than the diagonal dimension of the cross section of the optical element 4, the optical element 4 is accommodated when the optical element 4 is accommodated in the optical element accommodation hole 31. Positioning in the direction around the axis about the axis 31a by the inner surface of the hole 31 (contact of the optical element 4 with the inner surface of the optical element housing hole 31) (overlap of the contact surfaces 44a and 34a before reflow of the metal bumps) To secure). Further, when the metal bump 45 is reflowed, the optical element 4 freely rotates in the direction around the axis centering on the axis 31 a, so that the contact surface 44 a of each electrode pad 44 of the optical element 4 and the contact of the terminal portion 34. A case where the overlap with the surface 34a becomes very small or a case where the overlap disappears easily occurs.

  As shown in FIG. 9, the distance between the opposing inner surfaces of the four inner surfaces of the optical element accommodation hole 31 is smaller than the diagonal dimension of the cross section of the optical element 4, and the optical element accommodation hole 31 of the circuit board 3. If the rotation range in the direction around the axis centering on the axis 31a of the optical element 4 when the metal bump 45 is reflowed is set by the difference between the sectional dimension of the optical element 4 and the sectional dimension of the optical element 4, the metal bump 45 is melted. By self-alignment due to the surface tension of the bump material (bonding metal material), it is more reliable to ensure a sufficiently large overlap between the contact surface 44a of each electrode pad 44 of the optical element 4 and the contact surface 34a of the terminal portion 34. realizable.

  In this circuit board 3, the cross-sectional dimension of the optical element accommodation hole 31 is perpendicular to the axial center 31 a (center axis) of the optical element accommodation hole 31 in the optical element 4, and the contact surface of the electrode pad 44. 44a is larger by 5 to 195% of the dimension, and therefore the optical element 4 is positioned by the accuracy of the inner surface of the optical element storage hole 31 (the optical element 4 is positioned by fitting the optical element 4 into the optical element storage hole 31). Compared to the configuration, the operation of inserting and incorporating the optical element 4 into the optical element housing hole 31 can be performed easily and smoothly. Compared to the configuration in which the optical element 4 is positioned by the accuracy of the inner surface of the optical element storage hole 31 (the configuration in which the optical element storage hole 31 is positioned by fitting the optical element 4), the optical element is stored. Since the requirement for the formation accuracy of the inner surface of the hole 31 is considerably low, there is an advantage that the labor for processing the optical element housing hole 31 can be greatly reduced. Even if the formation accuracy of the inner surface of the optical element housing hole 31 is low, the self-alignment of the optical element 4 can be realized only by reflowing the metal bump 45 by the surface tension of the melted bump material (bonding metal material).

Further, since the self-alignment of the optical element 4 can be realized by the reflow of the metal bumps 35, it is not necessary to adjust the insertion position of the optical element 4 with respect to the optical element accommodation hole 31, and the operation of inserting the optical element 4 into the optical element accommodation hole 31 is possible. Can be done very easily.
As shown in FIG. 11A, variation is allowed in the positions of the optical elements 4 respectively accommodated in the plurality of optical element accommodation holes 31 of the circuit board 3. 11B, the plurality of optical elements 4 are overlapped with the contact surfaces 44a of the plurality of electrode pads 44 of the optical element 4 and the contact surfaces 34a of the terminal portions 34. Alignment with respect to the terminal portion 34 can be performed in a short time in a short time so as to be sufficiently large.

(Filled resin part forming process)
When the optical element mounting step is completed, a filling resin portion forming step for forming a filling resin portion 37 that fills the space between the inner surface of the optical element housing hole 31 and the optical element 4 is performed.
In this filling resin portion forming step, the opening portion of the optical element accommodation hole 31 in the joint surface 3b of the circuit board 3 (substrate with the optical element accommodation hole) is formed as an opening sealing member (FIGS. 12A and 12B). The liquid resin material 8 is injected into the optical element housing hole 31 in a state where the optical element housing hole 31 is closed using the opening sealing member denoted by reference numeral 7 and the optical waveguide substrate 2 in FIG. 13 (from the device mounting surface 3a side to the optical element). The filling resin portion 37 is formed by injecting into the storage hole 31. At this time, by securing a gap between the light receiving / emitting part installation surface 43 of the optical element 4 mounted on the circuit board 3 and the opening sealing member, together with the filling resin part 37, the filling resin part 37 Continuously, a transparent resin layer 38 that covers the light receiving / emitting portion installation surface 43 of the optical element 4 is also formed. In this case, the filling resin portion 37 and the transparent resin layer 38 are formed of the same resin material 8.
Note that the gap between the light receiving / emitting part installation surface 43 of the optical element 4 mounted on the circuit board 3 and the opening sealing member is such that the terminal part 34 is formed by a sheet-like or plate-like opening sealing member. This can be ensured by restricting bending into the optical element housing hole 31.

When the filling resin portion forming step is completed, the process proceeds to a mirror portion forming step in which the mirror portion 24 is formed on the optical waveguide substrate 2 attached to the bonding surface 3b of the circuit board 3.
When the filling resin portion forming step is completed, the above-described optical element built-in substrate 6 is obtained.

As the resin material 8 that forms the filling resin portion 37 and the transparent resin layer 38, it is preferable to employ, for example, an ultraviolet curable resin that can ensure transparency after curing, such as an epoxy resin.
In this case, the filling resin portion 37 and the transparent resin layer 38 can be easily formed by curing the resin material 8 injected into the optical element housing hole 31.

  In this filling resin portion forming step, as shown in FIG. 13, the optical waveguide substrate 2 itself attached to the bonding surface 3b of the circuit substrate 3 after completion of the optical element mounting step may be used as the opening sealing member. 12A, a sheet-like or plate-like opening sealing member 7 other than the optical waveguide substrate 2 is attached to the joining surface 3b of the circuit board 3, and into the optical element housing hole 31. As shown in FIG. The liquid resin material 8 may be injected.

(Filled resin part forming step 1)
First, the filling resin portion forming step will be described with reference to FIGS. 12 (a) and 12 (b).
12A and 12B, a sheet-like or plate-like opening sealing member 7 is attached to the bonding surface 3b of the circuit board 3, and the circuit board 3 (substrate with optical element accommodation holes) is attached. After injecting the liquid resin material 8 into the optical element accommodation hole 31 in a state where the opening of the optical element accommodation hole 31 in the joint surface 3b is closed, the resin material 8 is cured to fill the filling resin portion 37 and The transparent resin layer 38 is formed (filled resin portion forming step).
As the opening sealing member 7, it is preferable to use a material that is transmissive to ultraviolet rays, whereby the work of curing the resin material 8 injected into the optical element housing hole 31 by irradiation with ultraviolet rays can be efficiently performed in a short time. It can be carried out.
As the opening sealing member 7, for example, a synthetic resin transparent sheet or transparent plate, a glass plate, or the like can be employed. For example, polyimide, polynorbornene (PNB), benzocyclobutene (BCB), or the like can be employed as a material for forming the synthetic resin transparent sheet or transparent plate.

When the formation of the filling resin portion 37 and the transparent resin layer 38 is completed, the opening sealing member 7 is removed from the circuit board 3 as shown in FIG. The substrate 2 is attached, and the process proceeds to a mirror part forming step for forming the mirror part 24.
The transparent resin layer 38 is a protective layer for protecting the light receiving / emitting part 401 of the optical element 4, in particular, before the optical element built-in substrate 6 is bonded to the optical waveguide substrate 2. Functions as a protective layer for protecting against collisions of colliding objects, contamination due to dust adhesion, and the like.
In addition, after removing the opening sealing member 7 from the circuit board 3, for example, a flattening process of the transparent resin layer 38 on the bonding surface 3 b side of the circuit board 3 can be performed.

  In addition, as the opening sealing member 7 used in the filling resin portion forming step 1, the opening of the optical element storage hole 31 in the bonding surface 3 b of the circuit board 3 is sealed and injected into the optical element storage hole 31. In order to prevent leakage of the liquid resin material 8, it is not necessary to adhere to the entire bonding surface 3 b of the circuit board 3, for example, more than the opening of the optical element housing hole 31 in the bonding surface 3 b of the circuit board 3. It may be a slightly larger sheet-like or plate-like member, a cap-like member fitted into the opening of the optical element housing hole 31, or the like.

(Filled resin part forming step 2)
In the case of FIG. 13, as described above, the optical waveguide substrate 2 is attached to the joint surface 3b of the circuit substrate 3, and the optical waveguide substrate 2 itself is used as the opening sealing member, and the filling resin portion forming step is performed. Do.
In this case, in view of curing the resin material 8 injected into the optical element housing hole 31 by irradiation with ultraviolet rays, the optical waveguide substrate 2 can transmit ultraviolet rays in the cross-sectional direction of the optical waveguide substrate 2. The resin material 8 in the optical element housing hole 31 is irradiated with ultraviolet rays from the side opposite to the circuit board 3.

  The optical waveguide substrate 2 may be attached to the circuit board 3 by adhering the optical waveguide substrate 2 already formed into a sheet shape to the circuit board 3 by using an appropriate adhesive, for example, a three-layer structure. The optical waveguide forming body is formed by applying a varnish containing a resin material forming each layer of the optical waveguide forming body to the joint surface of the circuit board 3, and the core is formed by irradiating the optical waveguide forming body with active energy rays. The portion 22 may be formed so as to be attached to the circuit board 3.

  According to the manufacturing method of the optical waveguide module 1 including the filling resin portion forming step (filling resin portion forming step 2) described with reference to FIG. 13, the opening portion sealing member after the filling resin portion forming step is completed. Since the (optical waveguide substrate 2) is not removed from the circuit board 3, compared with the manufacturing method including the filling resin portion forming step (filling resin portion forming step 1) described with reference to FIGS. 12 (a) and 12 (b). Thus, the number of processes can be reduced.

In any of the filling resin part forming steps 1 and 2 described above, in a state where the transparent opening sealing member (opening sealing member 7 or optical waveguide substrate 2) is attached to the bonding surface 3b of the circuit board 3, The resin material 8 for forming the filling resin portion 37 and the transparent resin layer 38 is injected into the optical element housing hole 31, and the optical element is formed from the bonding surface 3b side of the circuit board 3 through the opening sealing member. The filling state of the resin material 8 into the storage hole 31 can be observed.
In addition, about the opening part sealing member 7 used by the filling resin part formation process 1, the opening part of the optical element accommodation hole 31 in the joint surface 3b of the circuit board 3 was sealed, and it inject | poured into the optical element accommodation hole 31 In terms of preventing leakage of the liquid resin material 8, it is not necessarily limited to a transparent material, and an opaque material can also be employed.

  When the filling resin portion forming step is completed, the process proceeds to a mirror portion forming step for forming the mirror portion 24 on the optical waveguide substrate 2.

(Mirror part formation process)
In the mirror portion forming step, the optical element 4 can be received / emitted through the optical waveguide substrate 2 (and the transparent resin layer 38) from the opposite side of the optical waveguide substrate 2 to the circuit board 3 (optical element built-in substrate 6). The optical waveguide substrate 2 is processed by aligning the position with the portion 401, and as illustrated in FIG. 2, FIG. 3, etc., the optical waveguide substrate 2 is formed with a V-shaped concave portion from the side opposite to the circuit substrate 3. A certain mirror part 24 is formed. The mirror part 24 is formed by, for example, laser processing or machining of the optical waveguide substrate 2.
Thereby, the optical waveguide module according to the present invention is obtained.

(Device mounting process)
In order to manufacture the optical waveguide module 1 in which the electronic device 5 is mounted on the optical element built-in substrate 6, that is, the optical waveguide module with device 1A, after the filling resin portion forming step is completed, before the mirror portion forming step, Alternatively, after the mirror part forming step, a device mounting step of mounting the electronic device 5 on the optical element built-in substrate 6 (circuit substrate 3) is performed.
In terms of ensuring workability in the mirror portion forming step, the device mounting step is preferably performed after the mirror portion forming step.

(Adopting optical elements with multiple light receiving / emitting sections)
As described above, the optical waveguide 4 applied to the optical waveguide module 1A with a device and the optical element built-in substrate 6 according to the present invention includes a plurality of receiving / emitting sections 401 on the receiving / emitting section installation surface 43. It is possible to adopt what is.
However, as shown in FIGS. 14A to 14C, for example, as shown in FIGS. 14A to 14C, the light receiving / light emitting portion installation surface 43 is provided so that the self-alignment of the optical element 4 with respect to the circuit board 3 can be performed as much as possible by reflowing metal bumps. In this case, it is preferable to adopt a configuration in which the electrode pads 44 are provided on both sides via the light receiving / emitting unit 401.
Reference numerals 4A, 4B, and 4C are assigned to the optical elements 4 in FIGS. 14A to 14C for distinction.

In the example shown in FIGS. 14A to 14C, the optical element 4 is a rectangular parallelepiped chip having a rectangular light receiving / emitting part installation surface 43.
The optical elements 4A and 4C shown in FIGS. 14A and 14C have a central portion in the width direction of the rectangular light receiving / light emitting portion installation surface 43 (in the direction along the short side of the rectangular light receiving / light emitting portion installation surface 43). A plurality of light receiving / light emitting portions 401 are arranged and arranged in a line along the longitudinal direction of the rectangular light receiving / light emitting portion installation surface 43 in the center portion, and the plurality of light receiving / light emitting portions 401 are arranged. The electrode pads 44 are installed at a plurality of locations on both sides via the light emitting unit installation row 401L.

  If the electrode pad 44 is provided on only one side of the both sides via the light receiving / emitting section installation row 401L, the optical element is stored in the optical element storage hole 31, and each electrode pad is stored. When the metal bump mounted on 44 is brought into contact with the contact surface 34a of the terminal portion 34, the optical element 4 is tilted, and even if the metal bump is reflowed, the optical element 4 self-acts on the circuit board 3. Alignment may not function effectively. On the other hand, as in the optical elements 4A and 4C shown in FIGS. 14A and 14C, the electrode pads 44 may be installed at a plurality of positions on both sides via the light receiving / emitting section installation row 401L. For example, when the optical element is stored in the optical element storage hole 31 and the metal bump mounted on each electrode pad 44 is brought into contact with the contact surface 34a of the terminal portion 34, the optical element 4 is useless. Inclination can be prevented, and self-alignment of the optical element 4 with respect to the circuit board 3 can be reliably performed by reflow of the metal bumps.

  In the optical element 4 having the rectangular light receiving / emitting part installation surface 43, the electrode pad 44 is rectangular in light receiving / emitting light in that the self-alignment of the optical element 4 with respect to the circuit board 3 effectively functions by reflow of metal bumps. It is preferable that the configuration is provided at a plurality of locations along the longitudinal direction of the light receiving / light emitting unit installation surface 43 on each of both sides in the width direction of the unit installation surface 43. In this regard, the light receiving / light emitting unit 401 is not necessarily arranged to form the light receiving / light emitting unit installation row 401L. For example, the light receiving / light emitting unit 401 is installed in the region where the electrode pad 44 is installed on both sides in the width direction of the light receiving / light emitting unit installation surface 43, and at the center in the width direction of the light receiving / light emitting unit installation surface 43. It does not exclude the configuration, etc. that are not installed.

The optical element 4B of FIG. 14B has a configuration in which the light receiving / emitting portion 401 and the electrode pad 44 are arranged in a line along the longitudinal direction of the rectangular receiving / light emitting portion installation surface 43.
In this case, when the optical element is accommodated in the optical element accommodation hole 31 and the metal bump mounted on each electrode pad 44 is brought into contact with the contact surface 34a of the terminal portion 34, FIG. Although the posture stability of the optical element is inferior to that of the optical elements 4A and 4C shown in (c), self-alignment of the optical element 4 with respect to the circuit board 3 by reflow of the bonding metal material (metal bump) can be realized without any problem.

Even when the optical element 4 formed on a rectangular chip having a rectangular light receiving / emitting part installation surface 43 is employed, a cross section perpendicular to the axis 31 a of the optical element housing hole 31 is taken as the optical element 4. The rectangular shape having a dimension slightly larger than the cross-sectional dimension perpendicular to the axis 31a of the optical element housing hole 31 (by 5 to 195% of the dimension of the contact surface 44a of the electrode pad 44) is square. This is the same as in the case of the optical element having the light receiving / emitting part installation surface 43.
Further, the optical element storage hole 31 having a rectangular cross section has a cross-sectional long side dimension perpendicular to the axis 31a (center axis) of the optical element storage hole 31 of the optical element 4 (the cross-sectional shape is rectangular. ) Smaller than the diagonal dimension.

When the optical element 4 having a configuration in which the light receiving / light emitting portions 401 are provided at a plurality of locations along the longitudinal direction of the rectangular light receiving / light emitting portion installation surface 43, a plurality of the optical elements 4 are used as the optical waveguide substrate 2. The one having the number of core portions 22 corresponding to the number of the light receiving / light emitting portions 401 (or may be larger than the number of the light receiving / light emitting portions 401) is adopted. Further, a mirror part 24 is provided at a position corresponding to each light receiving / emitting part 401 of the optical element 4, and an optical path and a light receiving / light emitting part corresponding to each core part 22 of the optical waveguide substrate 2 via the mirror part 24. 401 is optically coupled one-to-one.
The optical element 4 of the type having a plurality of light receiving / light emitting portions 401 that is currently on the market generally has an installation interval of the light receiving / light emitting portions 401 in the longitudinal direction of the rectangular light receiving / light emitting portion installation surface 43 of 250 μm. Is. In order to cope with this, the arrangement interval of the core portions 22 formed in parallel corresponding to the plurality of light receiving / emitting portions 401 of the optical element 4 in the optical waveguide substrate 2 is also set to 250 μm.
The arrangement interval of the core portions 22 formed in parallel to the optical waveguide substrate 2 is aligned with the installation interval of the light receiving / light emitting portions 401 in the longitudinal direction of the rectangular light receiving / light emitting portion installation surface 43 in the optical element 4. The installation interval of the parts 401 is not limited to 250 μm. In the case of other than 250 μm (for example, 125 μm), the arrangement interval of the core portions 22 is also aligned with the installation interval of the light receiving / emitting portions 401 accordingly.

(Another aspect)
Next, another aspect of the present invention will be described.
Here, the optical waveguide module 10 shown in FIG. 15 and the manufacturing method thereof will be described.
In the optical waveguide module 10 shown in FIG. 15, a sheet-like transparent member (opening sealing member 7) is interposed between the circuit board 3 and the optical waveguide substrate 2 of the optical waveguide module 1 shown in FIG. It has a structure.
The opening sealing member 7 is attached to the bonding surface 3 b of the circuit board 3, and the optical waveguide substrate 2 is bonded and fixed to the opening sealing member 7.
The optical path H2 between the light receiving / emitting part 401 of the optical element 4 of the circuit board 3 and the mirror part 24 formed on the optical waveguide substrate 2 corresponding to the light receiving / emitting part 401 is an opening sealing member 7. To penetrate.

As a manufacturing method of the optical waveguide module 10, for example, in the filling resin portion forming step, as shown in FIG. 12A, the transparent sheet-like opening sealing member 7 is formed on the bonding surface 3 b of the circuit board 3. After completion of the bonding and filling resin portion forming step, the optical waveguide substrate 2 is attached to the circuit board 3 without removing the opening sealing member 7 from the circuit board 3. Is attached so as to be laminated on the surface opposite to the circuit board 3 (see FIG. 15), and the process proceeds to the mirror part forming step.
In the process before the filling resin portion forming process, the optical element mounting process is performed in the same manner as in the above-described embodiment. Further, the steps after the mirror portion forming step can be performed in the same manner as in the above-described embodiment.

  The transparent opening sealing member 7 in this case can also transmit ultraviolet light in view of curing the resin material 8 injected into the optical element housing hole 31 by irradiation of ultraviolet light in the filling resin portion forming step. It is preferable to cure the resin material 8 by irradiating the resin material 8 in the optical element housing hole 31 with ultraviolet rays from the side opposite to the circuit board 3. In this regard, as the transparent opening sealing member 7, it is preferable to employ a transparent sheet made of a synthetic resin such as polyimide, polynorbornene (PNB), or benzocyclobutene (BCB).

  As a method of providing the optical waveguide substrate 2 on the surface of the opening sealing member 7 on the side opposite to the circuit substrate 3, the optical waveguide substrate 2 is attached to the bonding surface 3 b of the circuit substrate 3 in the embodiment described above. In the same manner as in the case of providing in a state, in addition to the application of the prepared optical waveguide substrate 2 (for example, bonding using an adhesive as appropriate), the formation of an optical waveguide forming body by application of varnish, The optical waveguide substrate 2 may be formed using the opening sealing member 7 itself as a base material by forming the core portion 22 by irradiating the waveguide forming body with active energy rays.

  According to the method for manufacturing the optical waveguide module 10, the opening sealing member 7 is not removed from the circuit board 3 after the filling resin portion forming step is completed. Therefore, the optical waveguide module 10 has been described with reference to FIGS. Compared to the manufacturing method, there is an advantage that the number of steps can be reduced.

(Other examples of manufacturing methods)
As described above, the optical waveguide module manufacturing method according to the present invention incorporates an optical element into the circuit board 3 in which the optical element housing hole 31 has been formed, and then integrates the optical waveguide board 2 into the circuit board 3. It is not limited to the structure provided, and as shown in FIGS. 16A, 16B, and 16C, wiring is performed after the optical waveguide substrate 2 is provided on the wiring-provided substrate 300 that does not have the optical element housing hole 31. An optical element in which the optical element housing hole 31 is formed in the attached substrate 300 to obtain the circuit board 3 (optical element housing hole forming process), and the optical element is mounted in the optical element housing hole 31 of the circuit board 3 for mounting. After performing the mounting process, the filling resin part forming process and the mirror part forming process may be performed in this order.
The steps after the filling resin portion forming step can be performed in the same manner as in the above-described embodiment.
Needless to say, a device mounting step may be performed after the mirror portion forming step.

As shown in FIG. 16A, the board with wiring 300 is different from the circuit board 3 only in that the optical element housing hole 31 is not provided. Other than the optical element housing hole 31, the wiring portion 32, the through wiring 33, and the terminal portion 34 are provided in the same manner as the circuit board 3.
However, in the substrate 300 with wiring, the terminal portion 34 is a part of the wiring pattern formed on one side of the substrate 300 with wiring (the surface on the side where the wiring portion 32 is formed; hereinafter referred to as the bonding surface 300b). It extends along the inner semiconductor substrate 39 of the substrate with wiring 300.

In this manufacturing method, first, as shown in FIG. 16A, the optical waveguide substrate 2 is provided on the bonding surface 300b of the substrate with wiring 300 (composite substrate forming step). By this step, a composite substrate 301 in which the optical waveguide substrate 2 is provided in a laminated state on the substrate with wiring 300 is obtained.
In order to provide the optical waveguide substrate 2 on the joint surface 300b of the substrate with wiring 300, the optical waveguide substrate 2 already formed in a plate shape is attached (for example, appropriately bonded using an adhesive). In addition, in the latter case, an optical waveguide forming body is formed by applying a varnish to the substrate with wiring 300, and the core portion 22 is formed by irradiating the optical waveguide forming body with active energy rays. A method of forming the optical waveguide substrate 2 integrally with the substrate with wiring 300 using the substrate with wiring 300 itself as a base material is also possible.

Next, as shown in FIG. 16B, an optical element accommodation hole forming step for forming the optical element accommodation hole 31 in the substrate with wiring 300 is performed. As the processing method, for example, laser processing using an excimer laser is suitable. In FIG. 16B, reference numeral 302 denotes a processing laser beam. In addition, reactive ion etching (RIE) or the like can also be employed.
The circuit board 3 is obtained by this optical element housing hole forming step. In addition, since the optical element housing hole 31 is formed, the terminal portion 34 has a protruding shape protruding from the wiring portion 32 to the opening of the optical element housing hole 31 in the bonding surface 300b.

When the optical element housing hole forming step is completed, an optical element mounting step for mounting the optical element in the optical element housing hole 31 is performed (see FIG. 16C). Thereafter, a filling resin portion forming step and then a mirror portion forming step are performed.
Upon completion of the mirror part forming step, an optical waveguide module having the structure shown in FIG. 3 can be obtained.
In the obtained optical waveguide module, the surface opposite to the bonding surface 300b of the circuit board 3 (the optical element built-in substrate 6) can be used as a device mounting surface 300a for mounting an electronic device such as an LSI.

  According to this manufacturing method, the optical waveguide substrate 2 is provided in a stacked state on the substrate with wiring 300 before the optical element housing hole 31 is formed, and the composite substrate 301 is formed. Since the optical element housing hole forming step of forming 31 is performed, the work of attaching the optical waveguide substrate 2 to the substrate with wiring 300 can be performed easily. The optical waveguide substrate 2 can be securely bonded even to a range including the position where the optical element housing hole 31 is to be formed on the substrate with wiring 300 (specifically, the bonding surface 300b). Adhesion with the optical waveguide substrate 2 can be easily secured.

In addition, this invention is not limited to the above-mentioned embodiment, It can change suitably.
(A) The present invention is an optical waveguide module having a configuration not including the filling resin portion 37 and the transparent resin layer 38, and an optical waveguide having only the filling resin portion among the filling resin portion 37 and the transparent resin layer 38. Includes modules. Moreover, about the manufacturing method of an optical waveguide module, the structure which does not comprise the filling resin part formation process is also included.
(B) In the method of manufacturing an optical waveguide module according to the present invention, after the optical waveguide substrate 2 is provided on the bonding surface 3b of the circuit substrate 3, a mirror portion is formed on the optical waveguide substrate 2 (mirror portion). (Formation step) The method is not limited to the configuration, and includes bonding the optical waveguide substrate 2 on which the mirror portion has been formed to the circuit substrate 3.
(C) The forming resin of the filling resin portion 37 and the transparent resin layer 38 is not limited to the ultraviolet curable resin. For example, a thermosetting resin such as a thermosetting epoxy is adopted, and in the filling resin portion forming step, the filling resin portion and the transparent resin portion are obtained by heat curing of the liquid resin material injected into the optical element housing hole. It is also possible to form
(D) The optical element built-in substrate according to the present invention may be any substrate as long as an optical element is incorporated in the optical element housing hole of the circuit board, and is not necessarily limited to a substrate having a filling resin portion and a transparent resin layer. Not.
(E) As illustrated in FIGS. 1 and 2, in the above-described embodiment, a light having a configuration in which one circuit board (substrate with a built-in optical element) and one optical waveguide substrate are integrated in a stacked state. Although the waveguide module has been illustrated, the present invention is not limited to this, and for example, a configuration in which the optical element built-in substrate is fixed (overlapped and integrated) at a plurality of locations on one sheet-like optical waveguide substrate can be adopted. is there.
(F) As a circuit board, it is not limited to what formed the optical element accommodation hole in the semiconductor substrate. For example, an electrically insulating insulating resin plate provided with an optical element housing hole, a wiring portion, a terminal portion, and a through wiring can be employed.

It is a front sectional view showing the structure of the optical waveguide module of the embodiment according to the present invention. FIG. 2 is a front sectional view showing a state (optical waveguide module with a device) in which an electronic device (LSI) is mounted on the optical waveguide module of FIG. 1. FIG. 3 is an enlarged cross-sectional view showing an area A indicated by a virtual line of the optical waveguide module in FIGS. 1 and 2, and an optical element accommodation hole formed in a circuit board and light incorporated in the optical element accommodation hole; The vicinity of the element is shown enlarged. It is a figure which shows the metal bump mounted in the circuit board before incorporating an optical element in the optical element accommodation hole of a circuit board, and the electrode pad of an optical element. It is a perspective view which shows the structure of the optical waveguide board | substrate of the optical waveguide module which concerns on this invention. 6A and 6B are diagrams for explaining an example of a method for manufacturing the optical waveguide substrate of FIG. 5, in which FIG. 6A is a perspective view showing a three-layer optical waveguide forming body, and FIG. 6B is an optical waveguide forming body of FIG. It is a perspective view which shows the state which formed the core part by irradiation of active energy of. It is a figure which shows the light-receiving / light-emitting part installation surface of an optical element. FIG. 3 is a plan view showing a state where a plurality of electrode pads (specifically, contact surfaces of electrode pads) of the optical element overlap with terminal portions (specifically, contact surfaces of terminal portions) of the circuit board. It is a top view which shows the relationship between the cross-sectional dimension of the optical element accommodation hole of a circuit board, and the cross-sectional dimension (especially diagonal dimension of a rectangular cross section) of an optical element. It is a front sectional view explaining tilting of an optical element in an optical element accommodation hole of a circuit board by reflow of a metal bump of the optical element. (A) and (b) are the figures (plan view) explaining the self-alignment of the optical element in the several optical element accommodation hole of a circuit board, (a) is before reflow of the metal bump of an optical element, (b) Indicates after reflow of metal bumps of the optical element. It is a figure explaining the filling resin part formation process of the manufacturing method of the optical waveguide module concerning the present invention, and (a) uses the opening part sealing member for the opening part of the optical element accommodation hole in the joint surface of a circuit board. The figure explaining the process of inject | pouring a liquid resin material in an optical element accommodation hole in the block | closed state, (b) removed the opening part sealing member from the circuit board after formation of a filling resin part and a transparent resin layer. It is a figure which shows a state. It is a figure explaining the filling resin part formation process of the manufacturing method of the optical waveguide module which concerns on this invention, Comprising: The optical element in the state which plugged the opening part of the optical element accommodation hole in the joint surface of a circuit board using the optical waveguide board | substrate It is a figure explaining the process of inject | pouring a liquid resin material in a storage hole. (A)-(c) is a figure which shows the example of the optical element which comprises multiple light receiving / light-emitting parts. It is a figure explaining another aspect of this invention, Comprising: It is a front sectional view which shows the structure of the optical waveguide module of the structure by which the transparent opening part sealing member is inserted between the circuit board and the optical waveguide board | substrate . (A)-(c) is a figure explaining the other example of the manufacturing method of the optical waveguide module which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical waveguide module, 1A ... Optical waveguide module with a device, 2 ... Optical waveguide board | substrate, 21 ... Cladding part, 22 ... Core part, 23 ... Optical waveguide formation body, 231 ... Core layer, 232 ... Cladding layer, 25 ... Bump Housing hole, 3 ... Circuit board, substrate with optical element housing hole, 3a ... Device mounting surface, 3b ... Bonding surface, 31 ... Optical element housing hole, 31a ... Axis, 32 ... Wiring section, 33 ... Through-wiring, 34 ... Terminal part, 34a ... contact surface, 35 ... bonding metal part, 351 ... metal bump, 36 ... bonding metal part, 37 ... filling resin part, 38 ... transparent resin layer, 39 ... semiconductor substrate (silicon substrate), 39a ... oxide film 4, 4A, 4B, 4C ... optical element, 401 ... light receiving / emitting part, 41 ... light emitting element, 411 ... light emitting part, 42 ... light receiving element, 421 ... light receiving part, 43 ... light receiving / light emitting part installation surface, 44 ... Electric Pads, 45 ... Metal bumps, 5 ... Electronic device (LSI), 5a ... Bottom surface, 51 ... Substrate, 52 ... Electronic circuit, 53 ... Via wiring, 6 ... Optical element built-in substrate, 61 ... Electronic device penetration wiring, 62 Metal bumps 63... Metal bumps 7. Opening sealing member 8. Resin material 9.

Claims (12)

An optical waveguide substrate having a linear core portion in a plate-like clad portion, and a circuit substrate attached to the optical waveguide substrate,
On the circuit board, an optical element which is a light receiving element or a light emitting element is housed and incorporated in an optical element housing hole penetrating the circuit board, and the optical element is disposed on an end surface facing the optical waveguide substrate. Having a light receiving / emitting part,
The optical waveguide substrate has a mirror part for forming an optical path between the optical waveguide of the optical waveguide substrate and the light receiving / emitting part of the optical element at a position corresponding to the light receiving / emitting part of the optical element. Have
The circuit board includes a wiring portion formed on a joint surface facing the optical waveguide substrate, a through wiring penetrating through the circuit board and connected to the wiring portion so as to be electrically conductive, and from the wiring portion to the joint surface. A projecting terminal portion projecting from the opening of the optical element storage hole in
The electrode pad provided on the end face of the optical element is bonded to the terminal portion and connected to be electrically conductive,
The electrode pad of the optical element and the terminal portion are bonded with a conductive bonding metal material,
The cross-sectional dimension of the optical element accommodation hole is a dimension obtained by increasing the cross-sectional dimension of the optical element perpendicular to the axis of the optical element accommodation hole by 5 to 195% of the dimension of the contact surface of the electrode pad. ,
The shape of the cross section of the optical element housing hole and the optical element is rectangular,
The distance between the opposing inner surfaces of the optical element housing hole is smaller than the diagonal dimension of the cross section of the optical element;
The optical element is capable of rotating and moving within the optical element accommodation hole while being set and regulated by the difference between the cross-sectional dimension of the optical element accommodation hole and the cross-sectional dimension of the optical element, and the axis of the optical element accommodation hole The contact surfaces of all electrode pads of the optical element have portions that overlap the contact surfaces of the terminal portions in plan view over the entire range of rotational movement of the optical element in the direction around the axis centering on the center. An optical waveguide module.   It is provided with a filling resin portion that fills a space between the inner surface of the optical element housing hole and the optical element, and the end surface of the optical element is covered with a transparent resin layer continuous from the filling resin portion. The optical waveguide module according to claim 1.   A transparent opening portion sealing member for sealing an opening portion that opens to the joint surface of the optical element housing hole is provided on a joint surface of the circuit board facing the optical waveguide substrate. Item 3. The optical waveguide module according to Item 2.   Electrode pads and metal bumps mounted on the electrode pads are provided on the joint surface of the circuit board, and the metal bumps are inserted into the optical waveguide via bump housing holes penetrating the optical waveguide board. The optical waveguide module according to claim 1, wherein the optical waveguide module protrudes from the waveguide substrate to a side opposite to the circuit substrate.   5. The optical waveguide module according to claim 1, wherein the mirror portion of the optical waveguide substrate is configured by a concave portion that is recessed from a side opposite to the circuit substrate of the optical waveguide substrate. . A method for manufacturing the optical waveguide module according to any one of claims 1 to 5,
A light receiving element or a light emitting element comprising a wiring portion formed on one or both sides of the semiconductor substrate, a through wiring penetrating the semiconductor substrate, and a through hole penetrating the semiconductor substrate. An optical element provided with an optical element housing hole in which an optical element is incorporated and a projecting terminal portion protruding from the wiring portion on one side of the semiconductor substrate into an opening at one end of the optical element housing hole The optical element is incorporated into the optical element accommodation hole of the substrate with the accommodation hole, and the metal bumps previously mounted on the electrode pad provided on the optical element are reflowed, and the electrode pad is used as the terminal portion. Optical element mounting process to be connected;
A light having a linear core portion in a plate-like clad portion and deposited on the side of the surface on which the wiring portion on which the terminal portion protrudes is formed on both surfaces of the substrate with the optical element housing hole. An optical path is formed between the optical waveguide of the optical waveguide substrate and a light receiving / emitting unit provided on an end surface of the optical element facing the optical waveguide substrate after the optical element mounting step on the waveguide substrate. A method of manufacturing an optical waveguide module, comprising: a mirror part forming step of forming a mirror part. In the manufacturing method of the optical waveguide module according to claim 6,
After the electrode pad is connected to the terminal portion, a filling resin portion forming step for forming a filling resin portion filling the space between the inner surface of the optical element housing hole and the optical element is performed, and then the mirror portion forming step is performed. An optical waveguide module manufacturing method characterized by the above. In the manufacturing method of the optical waveguide module according to claim 7,
In the filling resin portion forming step, in the state where the opening portion of the substrate with the optical element storage hole in which the terminal portion of the optical element storage hole is provided is blocked using an opening sealing member. A method of manufacturing an optical waveguide module, wherein a liquid resin material is injected into an element housing hole to form the filling resin portion. In the manufacturing method of the optical waveguide module according to claim 8,
In the filling resin portion forming step, a transparent resin layer covering the end face of the optical element is formed continuously from the filling resin portion. In the manufacturing method of the optical waveguide module according to claim 8 or 9,
After the completion of the filling resin portion forming step, after removing the opening sealing member from the substrate with the optical element accommodation hole, the optical waveguide substrate is attached to the substrate with the optical element accommodation hole, and then the mirror portion A method of manufacturing an optical waveguide module, comprising performing a forming step. In the manufacturing method of the optical waveguide module in any one of Claims 8-10,
Using a transparent opening sealing member, after completion of the filling resin portion forming step, after attaching the optical waveguide substrate to the substrate with the optical element housing hole with the opening sealing member attached, A method of manufacturing an optical waveguide module, wherein the mirror part forming step is performed. In the manufacturing method of the optical waveguide module in any one of Claims 8-10,
A method for manufacturing an optical waveguide module, wherein the filling resin portion forming step is performed using the optical waveguide substrate attached to the substrate with the optical element housing hole as the opening sealing member.

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