WO2022264322A1

WO2022264322A1 - Optical circuit device

Info

Publication number: WO2022264322A1
Application number: PCT/JP2021/022897
Authority: WO
Inventors: 光太鹿間; 洋平齊藤; 昇男佐藤
Original assignee: 日本電信電話株式会社
Priority date: 2021-06-16
Filing date: 2021-06-16
Publication date: 2022-12-22
Also published as: JPWO2022264322A1

Abstract

This optical circuit device (11) is provided with, in order, a waveguide substrate (111), an undercladding (112), a core through which resin curing light is guided, and an overcladding (115), and is provided with a resin core (121) cured by irradiating a photocurable resin with the resin curing light, and a resin cladding (122) disposed around the resin core and having a lower refractive index than the refractive index of the resin core. The resin curing light is emitted from the core through which the resin curing light is guided at one end of the optical circuit device (11), and the surface of the other end of the optical circuit device (11) is inclined toward the waveguide substrate side.　Consequently, the present invention can provide an optical circuit device with which it is possible to improve manufacturing process efficiency.

Description

Optical circuit device

The present invention relates to optical circuit devices using self-forming waveguides.

In order to respond to the rapid increase in Internet traffic in recent years, it is necessary to expand the communication capacity of the data center network. In order to cope with further expansion of transmission capacity and reduction of power consumption, the introduction of optical interconnection for transmission by light is progressing even for short and medium distance applications.

In a typical optical interconnection system, optical transmission such as an optical waveguide or an optical fiber is performed between a light emitting element such as a laser diode (LD) and a light receiving element such as a photodiode (PD) arranged on a printed circuit board. Signal processing is realized by transmission using a medium.

Depending on the transmission method, the optical light emitting element is integrated with an optical modulation element or the like, or connected discretely, and further connected to a driver or the like that performs electrical-to-optical conversion. A configuration including these light emitting elements, light modulating elements, drivers, etc. is mounted as an optical transmitter on an electrical mounting board such as a printed circuit board (PCB).

Similarly, the light-receiving element is appropriately integrated with an optical processor or the like, or connected discretely, and further connected with an electric amplifier circuit for performing optical-electrical conversion. A configuration including these light receiving element, optical processor, electric amplifier circuit, etc. is mounted on a printed circuit board as an optical receiver. Optical interconnection is achieved by mounting an optical transceiver, which integrates an optical transmitter and an optical receiver, in a package or on a printed circuit board and optically connecting it to an optical transmission medium such as an optical fiber. It is Also, depending on the topology, it is realized through a repeater such as an optical switch.

Semiconductors such as silicon and germanium, III-V group semiconductors such as indium phosphide (InP), gallium arsenide (GaAs), and indium gallium arsenide (InGaAs) are used as light emitting devices, light receiving devices, and light modulation devices. Devices using materials such as are put into practical use. In recent years, along with these elements, optical waveguide type optical transceivers have been developed in which a silicon optical circuit (silicon photonics) having a light propagation mechanism, an indium phosphorous optical circuit, or the like are integrated. In addition to semiconductors, materials such as ferroelectrics such as lithium niobate and polymers may also be used as light modulation elements.

Furthermore, optical functional elements such as planar lightwave circuits made of silica glass are sometimes integrated together with the above light emitting elements, light receiving elements, and light modulating elements. Optical functional devices include splitters, wavelength multiplexers/demultiplexers, optical switches, polarization control devices, optical filters, and the like. Hereinafter, a device in which a light emitting device, a light receiving device, an optical modulation device, an optical functional device, a light amplifying device, etc. having the above light propagation and waveguiding mechanisms are integrated will be referred to as an optical waveguide device. Among optical waveguide devices, optical waveguide devices using silicon photonics excel in integration, mass production, and compatibility with electrical components, and are attracting attention as key devices in realizing next-generation optical interconnection.

One of the representative methods for connecting an optical circuit device and an optical waveguide such as an optical fiber is to butt the optical circuit and the optical waveguide against one or more end faces that are responsible for the optical input/output of the optical circuit. It is a structure to connect. For example, an optical fiber array, which is one of the optical waveguides, is integrated with glass or the like in which a V-groove is formed, and each core of the optical fiber and each core of the optical circuit device in this array structure are positioned. connected. At this time, in order to minimize the connection loss, it is necessary to position (hereinafter referred to as alignment) and fix each core of the optical circuit device and each core of the optical fiber in submicron units. In this positioning, light is input and output, alignment is performed simultaneously with power monitoring (optical alignment), and adhesive or the like is filled and fixed (active alignment, Non-Patent Document 1).

An optical connection technology using a self-forming waveguide has been proposed as a technology for connecting while relaxing this positioning accuracy. This technique forms a self-forming waveguide by filling a photocurable resin between waveguide cores to be connected and irradiating the photocurable resin with resin curing light from the cores to be connected. At this time, by emitting resin curing light from both waveguide cores to be connected, self-forming waveguides are formed so as to absorb the positional error of each core, and connection loss is reduced.

As a result, good connection loss can be obtained even with mechanical positioning accuracy that does not use active alignment, so self-forming waveguide technology is expected to improve the mountability of optical circuit devices. In the self-forming waveguide technology, as shown in FIGS. 14A and 14B, a self-forming waveguide core 821 is formed by irradiating resin curing light from a core 814 of an optical circuit device 81, and one side of the self-forming waveguide core 821 is formed. The end face is connected to the core 814 end face of the optical circuit device 81 . Also, one end face of the self-forming waveguide core is connected to the optical fiber to be connected (not shown).

The optical circuit device may be any known optical circuit device, but in silicon photonics, for example, it is difficult to propagate light in the visible to ultraviolet range, which is the wavelength of general resin curing light. Therefore, as shown in FIGS. 14A and 14B, a second waveguide core 814 made of SiON, SiN, SiO2, or the like, which is transparent in the same wavelength range, is provided. A second waveguide core 814 is provided on top of the first waveguide core 813 and functions as a spot size converter at the signal wavelength. The resin curing light 84 propagates through the second waveguide cores 814 and 814_2 and is emitted from the end surface of the optical circuit core. At this time, as a method of inputting the resin curing light to the second waveguide core 814 , the resin curing light 84 is input by abutting the optical fiber 83 against one end of the second waveguide core 814 .

However, in a conventional optical circuit device having a self-forming waveguide, in order to input resin curing light into the optical circuit device, an optical fiber having a core coaxial with the optical circuit core at one end of the waveguide core is used to form a resin. It was necessary to enter for hardening. Here, when forming a self-forming waveguide core (hereinafter referred to as a "resin core"), in the longitudinal direction of the optical circuit core, the input optical fiber, the optical circuit device, the resin core, and the other to be connected are separated from each other. Since optical fibers and optical circuit devices (not shown) are arranged, a large footprint is required.

Furthermore, with conventional self-forming waveguide technology, it is difficult to form self-forming waveguides on multiple silicon photonics chips at once. It was difficult.

As described above, in optical circuit devices using conventional self-forming waveguides, the area (footprint) required for mounting work when forming and connecting self-forming waveguides is large, and multiple self-forming waveguides are formed at once. There was a problem in manufacturing process efficiency such as inability to form a waveguide.

In order to solve the above-described problems, an optical circuit device according to the present invention includes a waveguide substrate,
An optical circuit device comprising: an undercladding; a core through which resin curing light is guided; and a resin clad having a refractive index smaller than that of the resin core, the resin curing light being guided at one end of the optical circuit device. It is characterized in that the surface of the other end portion of the optical circuit device, which is emitted from the core, is inclined toward the waveguide substrate side.

Further, an optical circuit device according to the present invention is an optical circuit device comprising, in order, a waveguide substrate, an undercladding, a core through which resin curing light is guided, and an overcladding, wherein the resin is added to the photocurable resin. a resin core that is cured by being irradiated with curing light; and a resin clad that is disposed around the resin core and has a lower refractive index than the resin core, wherein the resin curing light is irradiated with the At one end of the optical circuit device, the resin curing light is emitted from the core through which the resin curing light is guided, and a part of the surface of the optical circuit device is inclined toward the core through which the resin curing light is guided. characterized by

Further, an optical circuit device according to the present invention is an optical circuit device comprising, in order, a waveguide substrate, an undercladding, a core through which resin curing light is guided, and an overcladding, wherein the resin is added to the photocurable resin. a resin core that is cured by being irradiated with curing light; and a resin clad that is disposed around the resin core and has a lower refractive index than the resin core, wherein the resin curing light is irradiated with the At one end of the optical circuit device, the core through which the resin curing light is guided is emitted, and an optical path changing component is connected to or close to the core through which the resin curing light is guided at the other end surface of the optical circuit device. characterized by

According to the present invention, an optical circuit device capable of improving manufacturing process efficiency can be provided.

FIG. 1 is a schematic side sectional view showing the configuration of an optical circuit device according to the first embodiment of the present invention. FIG. 2A is a schematic side sectional view showing the configuration of the optical circuit device according to the first embodiment of the invention. FIG. 2B is a schematic top cross-sectional see-through view showing the configuration of the optical circuit device according to the first embodiment of the present invention. FIG. 3 is a schematic side sectional view showing an example of the configuration of the optical circuit device according to the first embodiment of the invention. FIG. 4 is a schematic cross-sectional side view showing the configuration of an optical circuit device according to a second embodiment of the invention. FIG. 5 is a schematic cross-sectional side view showing the configuration of an optical circuit device according to a third embodiment of the invention. FIG. 6 is a schematic cross-sectional side view showing an example of the configuration of an optical circuit device according to the third embodiment of the invention. FIG. 7A is a schematic side cross-sectional view showing the configuration of an optical circuit device according to a fourth embodiment of the present invention; FIG. 7B is a schematic side sectional view showing an example of the configuration of the optical circuit device according to the fourth embodiment of the invention. FIG. 8 is a schematic cross-sectional side view showing the configuration of an optical circuit device according to a fifth embodiment of the invention. FIG. 9 is a schematic cross-sectional side view showing the configuration of an optical circuit device according to the sixth embodiment of the invention. FIG. 10 is a schematic cross-sectional side view showing the configuration of an optical circuit device according to the sixth embodiment of the invention. FIG. 11 is a schematic cross-sectional side view showing an example of the configuration of an optical circuit device according to the sixth embodiment of the invention. FIG. 12 is a schematic side sectional view showing the configuration of an optical circuit device according to the seventh embodiment of the invention. FIG. 13A is a schematic side cross-sectional view showing an example of the configuration of an optical circuit device according to the seventh embodiment of the present invention; FIG. 13B is a schematic side cross-sectional view showing an example of the configuration of the optical circuit device according to the seventh embodiment of the present invention; FIG. 13C is a schematic side cross-sectional view showing an example of the configuration of an optical circuit device according to the seventh embodiment of the present invention; FIG. 13D is a schematic cross-sectional side view showing an example of the configuration of the optical circuit device according to the seventh embodiment of the present invention; FIG. 14A is a schematic side sectional view showing the configuration of a conventional optical circuit device. FIG. 14B is a schematic top sectional perspective view showing the configuration of a conventional optical circuit device.

<First Embodiment>
An optical circuit device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG.

<Structure of optical circuit device>
As shown in FIG. 1, the optical circuit device 11 according to the present embodiment includes, in order, a waveguide substrate 111, an undercladding 112, a first waveguide core 113, a second waveguide core 114, and an overcladding. 115 , and a photocurable resin core (hereinafter referred to as “resin core”) 121 and a photocurable resin clad (hereinafter referred to as “resin clad”) 122 of the self-formed waveguide.

Here, the waveguide layer of the optical circuit device 11 is composed of an undercladding 112 , a first waveguide core 113 , a second waveguide core 114 and an overcladding 115 .

Here, the resin curing light emitted from the second waveguide core 114 of the optical circuit device 11 is applied to the photocurable resin arranged on the emitting surface, and the photocurable resin core (hereinafter referred to as “resin core”) .) 121 is formed. As a result, the resin core 121 is connected to the surface from which the resin curing light is emitted.

In the optical circuit device 11, resin curing light is incident from an arbitrary end face (referred to as a “resin curing light incident end face” or “incidence end face”) near 116 (including the end face), and other end faces (“resin curing light 117 (including the end face). In this embodiment, the end surface 116 for incidence of resin curing light and the end surface 117 for emission of resin curing light are arranged at positions facing each other.

Hereinafter, in the horizontal plane (waveguide substrate 111 surface), the direction in which light is guided in the second waveguide core 114 in the vicinity of the resin curing light output end face 117 in the optical circuit device 11 (the X direction in the drawing) is defined as " The direction perpendicular to the longitudinal direction (the Y direction in the drawing, the depth direction on the paper surface) is defined as the "width direction," and the direction perpendicular to the horizontal plane (surface of the waveguide substrate 111) (the Z direction) is defined as the "longitudinal direction of the optical circuit core." "thickness direction".

In the optical circuit device 11 , the resin core 121 is connected to the end surface of the second waveguide core 114 at the output end surface 117 .

Further, in the optical circuit device 11, the surface of the incident end surface 116 is inclined so as to face the waveguide substrate 111 side (downward in this embodiment) as the optical path conversion structure. Here, the "surface" of the surface refers to the surface facing the outside of the optical circuit device 11 and the surface on the side that comes into contact with the external environment such as the atmosphere.

In the optical circuit device 11, a plurality of first waveguide cores 113 and second waveguide cores 114 are arranged in the width direction (Y direction) (not shown).

The optical circuit device 11 is a known silicon photonics chip, an optical waveguide layer is formed on a BOX layer 112 on a waveguide substrate 111, and the thickness of the waveguide substrate 111 is, for example, a standard silicon wafer thickness. It is 625 μm, which is the height.

Although not shown in the drawings, the light-emitting element, light-receiving element, modulation element, optical functional element, etc. described in the background are integrated, and electrical wiring layers, electrical pads, etc. are also integrated as necessary.

In addition, the optical circuit device 11 is integrated in a hybrid manner with an optical transmission element, an optical modulation element, and the like made of a compound semiconductor or the like, if necessary. Although not shown in the drawings, the optical circuit device 11 is mounted and fixed on a subcarrier, a package, an electric wiring board, or the like.

In the following, light emitted from a silicon photonics chip will be described as an example, but the operation when incident on a silicon photonics chip is also reversible, and the present invention naturally does not depend on the input/output direction of light.

A silicon photonics chip is equipped with an optical input/output unit for inputting/outputting light to the outside on at least one optical input/output end face, and a spot size converter (SSC, arrow 113_2 in FIG. 2B) as an edge coupler is an optical circuit. accumulated within. In general, the mode field diameter of the light propagation mode in the optical circuit of silicon photonics is very small, 1 μm or less. ) is done.

At this time, in the SSC portion, the Si fine wire 113, which is the first waveguide core, is formed in a tapered shape such that the tip shape becomes thinner. A second waveguide core 114 is formed to cover the first waveguide core (Si wire) 113 or to be close to the first waveguide core (Si wire) 113 . In the tapered Si wire, it becomes difficult for light to be confined in the Si core, and the mode field diameter widens. transitions to the second waveguide core 114 . Thus, the second waveguide core 114 is arranged to be optically coupled to the first waveguide core 113 . The material of the second waveguide core 114 is SiON, for example.

As for the shape of the Si wire 113, a non-linear tapered shape, a multi-stage tapered shape, or an SSC structure consisting of a discontinuous body of a Si core and a glass material, known as segmented SSC, may be used as needed. Further, the second waveguide core 114 is made of a material capable of propagating the curing wavelength of the photocurable resin, and may be made of glass, SiON, polymer, or the like other than SiON.

As shown in FIGS. 1 to 2B, a resin core 121 made of a photocurable resin extends along the length of the optical circuit core so as to be in contact with the end surface of a core (second waveguide core) 114 responsible for optical input/output of the optical circuit device 11. formed in the direction The photocurable resin is a known resin that reacts to a specific wavelength and undergoes a curing reaction. For example, acrylic resin, epoxy resin, silicone resin, urethane resin, oxetane resin, organic-inorganic hybrid, modified products thereof, or Substituents and the like can be used, and materials known as photoresists may be used. The curing wavelength can be arbitrarily designed by adding an initiator, a dye, and the like, and for example, wavelengths from ultraviolet light to visible light can be used.

The photocurable resin core 121 is formed by gradually curing uncured resin by resin curing light emitted from the end surface of the second waveguide core 114, and is in contact with the second waveguide core 114.

A resin clad 122 is arranged around the resin core 121 . The refractive index of the resin clad 122 is lower than that of the photocurable resin core 121 in the signal wavelength band. Known acrylic resins, epoxy resins, silicone resins, urethane resins, oxetane resins, and the like can be used as the resin clad material, and halogen-substituted compounds such as fluorination may be used as appropriate to adjust the refractive index.

Although the cross-sectional shape of the photo-curing resin core 121 is arbitrary, it is formed to have a shape similar to the mode distribution from the optical circuit core. For example, a Gaussian beam has a shape close to a circular cross section. In practice, the mode shape may be elliptical.

The resin core 121 is connected to an optical component such as an optical fiber to be connected or a second optical circuit device, and functions as an intermediary waveguide. Note that optical fibers, optical circuit devices, polymer waveguides, etc., to be connected are omitted in the drawings.

As the layout of the optical circuit of this embodiment, as shown in FIG. It is configured to receive light.

In the present embodiment, the end face (incidence end face) 116 on the resin curing light input side is arranged at a position facing the emission end face 117 on which the resin core 121 is formed, but it may be arranged on any surface. good. For example, by bending or curving the second waveguide core 114 by 90 degrees, the end face in the depth direction (Y+ direction) or the front direction (Y− direction) of the paper surface may be used as the incident end face 116 . Further, as will be described later, the resin curing light input portion of the second waveguide core 114 may be arranged on the same surface as the surface in contact with the resin core 121 or may be provided inside the optical circuit device 11 .

Here, in the present embodiment, as shown in FIG. 1, the incident end surface 116 is inclined toward the waveguide substrate 111 side (downward in FIG. 1). In other words, the end surface has an inclination angle such that the overcladding 115 of the optical circuit device 11 protrudes relative to the waveguide substrate 111 in the X-direction. This inclined end face (hereinafter referred to as "resin curing light incident oblique end face" or "incident oblique end face") 116 is formed by machining such as dicing or polishing, and is set at an angle of, for example, 45°. there is

As shown in FIGS. 2A and 2B, the input optical fiber 21 is arranged on the upper surface of the optical circuit device 11 (waveguide layer) near the incident oblique end face 116, and the resin curing light 22 is input. The resin curing light 22 is emitted light from an LD with a wavelength of 405 nm, for example, and propagates through the input optical fiber 21 .

As shown in FIG. 2A , the resin curing light 22 is reflected at the rear surface of the oblique end face 116 for incidence, is converted by 90°, is coupled to the second waveguide core 114, and propagates through the second waveguide core 114. Later, the light is emitted from the emission end face 117 filled with uncured photocurable resin. A resin core 121 is formed as a self-forming waveguide according to the resin curing light 22 .

After that, before filling the clad resin that covers the resin core, the uncured portion of the photocurable resin is removed, and a different material is filled and fixed. If the refractive index difference of the waveguide can be obtained by the resin characteristics, the photocurable resin may be used as it is as the clad material. For example, by using a resin with a different resin refractive index after curing depending on the curing wavelength, curing mechanism, addition of a copolymer, etc., the refractive index is kept lower than that of the photocurable resin core 121, and the resin is used as it is as a clad material. can also

Although an example in which the input optical fiber 21 and the overcladding 115 of the optical circuit device 11 are in contact is shown here, a lens or the like may be inserted between the input optical fiber 21 and the optical circuit device 11 . Also, a lens may be provided on the top surface of the optical circuit or on the end surface of the input optical fiber 21 .

As shown in FIG. 2B, the width of the second waveguide core 114 is designed to be widened as necessary in the vicinity of the resin curing light input portion, that is, the optical path changing structure. For example, the second waveguide core 114 has a width of about 2 to 4 μm in the SSC portion, but is expanded to about 10 to 50 μm in the vicinity of the resin curing light input portion.

With this structure, the positioning accuracy of the resin curing light can be designed looser than the positioning accuracy of the conventional method. In general, since the light output required for curing the resin is very small, the alignment accuracy of the resin curing light can be aligned based on the image observation accuracy from the top surface, for example, even if the alignment accuracy is not active alignment.

<effect>
Effects of the optical circuit device according to the present embodiment will be described below.

In a conventional optical circuit device having a resin core, in order to input resin curing light, it is necessary to input the resin curing light using an optical fiber having a core coaxial with the optical circuit core at one end of the waveguide core. was there. As a result, a large footprint is required, including the alignment space for the input fiber, and it is difficult to form self-assembled waveguides on multiple silicon photonics chips at once, creating problems in manufacturing process efficiency.

On the other hand, according to the optical circuit device according to the present embodiment, the input optical fiber can be arranged from the upper surface of the optical circuit device when resin curing light is input, so that the footprint can be significantly reduced. . In addition, since the core position can be adjusted and positioned by image observation from the upper surface of the optical circuit device, mounting workability (manufacturing process efficiency) can be greatly improved.

In addition, since the input optical fiber can be input from the top surface, it is possible to mount multiple chips side by side, and it is possible to form a resin core at the wafer level, which has the effect of greatly improving mounting workability.

It should be noted that the present invention can be similarly applied to optical circuit devices other than silicon photonics, such as InP integrated circuits, quartz PLCs, and LN circuits.

As shown in FIG. 3, a quartz-based PLC may be used as the optical circuit device 11. Si wires and InP waveguides strongly absorb visible light to ultraviolet light, which is resin curing light, but quartz PLC, LN, polymer, etc. can propagate resin curing light, and the second waveguide is unnecessary.

Alternatively, the entire optical circuit device 11 and resin core 121 may be covered with a clad (resin) 122 .

Further, as shown in FIG. 3, the oblique end face 116 for incidence of resin curing light may be coated with a high reflection film 118 . A highly reflective film coat can be easily formed by vapor-depositing a dielectric multilayer film, metal, or the like. Thereby, the reflection efficiency of reflection can be made sufficiently high.

In addition, if there is a clad resin or other mold resin, there is a risk that the refractive index difference necessary for reflection with high reflection efficiency cannot be obtained, but by coating the highly reflective film, the entire surface is covered with resin. Even in this case, it is possible to achieve reflection of resin curing light with high reflection efficiency. Of course, any combination of these and the configuration of FIG. 1 can be selected.

Also, any known optical fiber may be used as the optical fiber. Also, an optical waveguide device such as a polymer waveguide may be used as an optical component other than an optical fiber.

Also, although an optical path conversion of 90° by a 45° mirror is shown as an example, the angle may be changed to a predetermined design value if it is possible to input light to the waveguide core and resin curing light can be input from the upper surface. . In addition, an example in which the oblique end surface for resin curing light incidence and the reflecting surface of the mirror component are inclined at an angle of 45° and the optical path is converted by 90° has been shown, but the angle of inclination of the reflecting surface is not limited to this. Any angle may be used as long as the curing light can be incident on the waveguide core.

<Second Embodiment>
An optical circuit device according to a second embodiment of the present invention will be described with reference to FIG.

<Structure of optical circuit device>
In the optical circuit device according to this embodiment, the basic components are the same as in the first embodiment, the optical circuit device is an InP circuit, and the second waveguide core 114 is polymer.

The difference from the first embodiment is that, as shown in FIG. 4, an oblique end surface 131 for resin curing light incidence is formed in the optical circuit device as an optical path conversion structure. Here, the surface of the oblique end surface 131 for incidence of resin curing light is inclined toward the overcladding 115 side. A certain gap is provided between the oblique end surface 131 for incidence of resin curing light and the second waveguide core 114 through which the resin curing light is propagated.

The resin curing light is input from the upper surface of the optical circuit device 11 (waveguide), and is reflected by the highly reflective film 132 on the oblique end surface 131 for resin curing light incidence, so that the optical path is converted, and the light path is changed to the second waveguide core 114. is entered.

Any known method may be used for forming a mirror structure in such an optical circuit device. For example, it can be formed by machining with a blade having a specified angle using dicing or the like. Alternatively, it can be formed using an etching technique in a wafer process. Alternatively, another rectangular groove may be formed and then resin may be applied to utilize surface tension to form a similar mirror shape.

In this embodiment, the same effect as in the first embodiment can be obtained. That is, since the input optical fiber can be arranged from the upper surface of the optical circuit device when resin curing light is input, the footprint can be greatly reduced.

In addition, since the core position can be adjusted and positioned by observing the image from the top of the optical circuit device, mounting workability can be greatly improved.

In addition, manufacturing efficiency can be greatly improved because the oblique end face can be formed in a batch process, such as a wafer process, rather than for each chip. In addition, by integrating the oblique end faces in the circuit, the size of the optical circuit device can be reduced.

<Third Embodiment>
An optical circuit device according to a third embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG.

<Structure of optical circuit device>
The basic components of the optical circuit device according to this embodiment are the same as those of the first embodiment.

The difference from the first embodiment is that, as shown in FIG. 5, as an optical path conversion structure, an oblique end surface for resin curing light incidence is not provided in the optical circuit device, and an optical path conversion component 31 is provided on the end surface of the optical circuit device. 116 and integrated. Here, the surface of the inclined surface of the optical path conversion component 31 is inclined downward. The optical path conversion component is, for example, a mirror component such as a prism mirror, and is made of glass, Si, polymer, or the like. The optical path conversion component 31 is fixed to the optical circuit device 11 with an adhesive.

The resin curing light is input from the end face parallel to the top surface of the optical circuit device in the optical path changing component, reflected on the back surface of the inclined surface of the optical path changing component, and the optical path is changed, and is input to the second waveguide core 114. be done.

In addition, by performing the optical path conversion with a separate component instead of the oblique end face, there is no need to process the optical circuit device itself, and the mass productivity of the optical circuit device is improved. Although the optical path conversion component is separately prepared, it is easy to manufacture a desired mirror component with high mass productivity, and integration with an optical circuit device can be easily performed. As a result, the yield of the entire optical circuit device can be improved.

Further, as shown in FIG. 6, a beam diameter adjusting component 33 may be provided by connecting to the end face of the optical path converting component 31 on the resin curing light incident side.

Conventionally, when light propagates through the optical path changing component, the beam diameter of the light expands, so the beam diameter is likely to be mismatched with the second waveguide core.

On the other hand, as shown in FIG. 6, a beam diameter adjusting component 33 such as a lens, a GRIN lens, a GI fiber, or the like is used to adjust the beam diameter to a desired beam diameter at the second waveguide core 114 coupling portion. Resin curing light can be easily input to the second waveguide core 114 without diameter mismatch.

<Fourth Embodiment>
An optical circuit device according to a fourth embodiment of the present invention will be described with reference to FIGS. 7A and 7B.

The difference from the first embodiment is that, as shown in FIGS. 7A and 7B, as an optical path conversion structure, an oblique end surface for resin curing light incidence is not provided in the optical circuit device, and an optical path conversion component 41 is provided in the optical circuit device. is arranged close to the end face of the Here, the surface of the oblique end surface of the optical path conversion component 41 is inclined toward the overcladding 115 side. The optical path conversion component 41 is a mirror component such as a triangular prism mirror (FIG. 7A) or a cube prism mirror (FIG. 7B), and is made of glass, Si, polymer, or the like. The optical path conversion component 41 and the optical circuit device 11 are mounted on a mounting board 42 and fixed by an arbitrary method.

The resin curing light is input from the upper surface of the optical path conversion component 41 (upper side in FIGS. 7A and 7B), is reflected by the optical path conversion component 41 to change the optical path, and is input to the second waveguide core 114.

Also, as shown in FIG. 7B, considering the spread of the beam diameter, a lens, a GRIN lens, a GI fiber, or the like may be used as the beam diameter adjusting component 43 . As a result, resin curing light can be easily input to the second waveguide core 114 by adjusting the beam diameter to a desired beam diameter at the coupling portion of the second waveguide core 114 .

In addition, it is possible to mount the optical path conversion parts on the substrate with good mass production efficiency using an electronic component mounting machine such as a chip mounter, further improving the mounting workability.

As the mounting substrate, an electrical wiring substrate such as a PCB or a buildup, an electrical rewiring layer made of a thin film made of resin, a ceramic substrate, or an interposer made of Si, glass, glass epoxy, resin, or the like may be used. In addition, although the figure shows an example of face-up mounting in which the waveguide layer is on the upper surface as mounting of the chip on the substrate, it is of course possible to apply face-down mounting.

<Fifth Embodiment>
An optical circuit device according to a fifth embodiment of the present invention will be described with reference to FIG.

<Structure of optical circuit device>
The basic components of the optical circuit device according to this embodiment are the same as those of the fourth embodiment.

The difference from the fourth embodiment is that, as shown in FIG. 8, an optical path conversion component 51 is integrated in the optical circuit device 11 as an optical path conversion structure. Here, the surface of the oblique end surface of the optical path conversion component 51 is inclined toward the overcladding 115 side. The optical path conversion component 51 is, for example, a microprism mirror.

The optical circuit device 11 has a groove (terrace, cavity) 52 in which a mirror can be mounted inside the optical circuit device 11, and an optical path conversion component 51 is mounted in this groove 52 and fixed by an arbitrary method. . The grooves 52 in the optical circuit device 11 can be formed by any method such as known etching.

The resin curing light is input from the upper surface (upper side in FIG. 8) of the optical path changing component 51, and is reflected by the optical path changing component 51 to change the optical path. It is input to the second waveguide core 114 after propagating through the air gap.

As in the fifth embodiment, considering the spread of the beam diameter, for example, a lens, a GRIN lens, a GI fiber, etc. are used to adjust the desired beam diameter at the coupling portion of the second waveguide core 114. good too.

In addition, it is no longer necessary to process the oblique end face of the optical circuit device itself, which improves the mass productivity of the optical circuit device. Although the optical path conversion component is separately prepared, it is easy to manufacture a desired mirror component with high mass productivity, and integration with an optical circuit device can be easily performed. As a result, the yield of the entire optical circuit device can be improved.

In addition, it is possible to mount the optical path conversion component on the optical circuit device with good mass productivity using an electronic component mounting machine such as a chip mounter, further improving the mounting workability. Furthermore, the optical circuit device can be made smaller by integrating the optical path changer in the circuit.

<Sixth Embodiment>
An optical circuit device according to a sixth embodiment of the present invention will be described with reference to FIGS. 9 to 11. FIG.

The difference from the first embodiment is that the optical circuit device 11 is mounted face down on the mounting substrate 63 as shown in FIG. Here, a known flip-chip connection is used as a face-down mounting method, and connection is made via electrical contacts such as metal.

There are electrical wiring (not shown) and electrical contact pads (not shown) on the mounting substrate 63, which are electrically connected to the electrical wiring (not shown) and electrical contact pads of the optical circuit device. .

In the optical circuit device, a reflective structure 61 is provided between the overcladding 115 of the waveguide layer and the electrical contact 62 . Reflective structure 61 is, for example, a gold or aluminum pad for flip-chip bonding.

In addition, in the present embodiment, as the optical path conversion structure, the oblique end surface 116 for resin curing light incidence is inclined toward the waveguide substrate 111 side (upward in FIG. 9). In other words, the end faces are formed such that the overcladding 115 of the optical circuit device protrudes relative to the waveguide substrate 111 in the X-direction.

As shown in FIG. 10, the resin curing light 22 is refracted after being input from the waveguide substrate 111 side and is transmitted (propagated) through the waveguide layer. The resin curing light 22 transmitted through the waveguide layer is reflected by the reflecting structure 61 and then transmitted through the waveguide layer again. After that, it is input to the second waveguide core 114 by being reflected by the back surface of the oblique end surface 116 .

In addition, in face-down mounting such as flip chip connection, resin curing light can be input from the thickness direction (upper in FIG. 10) without using an additional mirror component, increasing the degree of freedom in the mounting method of the optical circuit device. can be expanded.

In this embodiment, an example of using a metal pad for flip-chip connection as the reflective structure is shown. Effective.

Further, as shown in FIG. 11, through vias may be formed in the mounting substrate, and resin curing light may be input from the through via side.

<Seventh Embodiment>
An optical circuit device according to a seventh embodiment of the present invention will be described with reference to FIGS. 12 to 13D.

The difference from the first embodiment is that the optical path changing structure 71 is also provided on the output end face 117 side where the resin core is formed. As in the first to sixth embodiments, the optical path changing structure 71 can be applied by any method such as total reflection, a mirror, or an oblique end surface.

Further, in the present embodiment, the optical path of the resin curing light emitted after propagating through the second waveguide core 114 is changed by the optical path conversion structure 71 in the vicinity of the output end face 117 including the output end face 117 . As a result, the photocurable resin core 121 extends perpendicularly to the longitudinal direction of the optical circuit core (in the thickness direction) and is formed in contact with the upper surface of the overcladding 115 .

In this embodiment, effects similar to those of the first embodiment can be obtained. That is, since the input optical fiber can be arranged from the upper surface of the optical circuit device when resin curing light is input, the footprint can be greatly reduced.

In addition, by connecting the resin core to the upper surface of the optical circuit device and forming it, it is possible to arrange the connection target on the upper surface, further improve the mounting workability, and increase the degree of freedom in the mounting layout. For example, new structures such as integration of optical circuit devices and optical fibers at the wafer level, integration of optical circuit devices, and exposure of a resin core from the upper surface of a resin mold package can be realized.

In the present embodiment, as shown in FIG. 13A, the resin core 121 can be formed on the upper surface of the overcladding 115 by making the outgoing end face 117 as well as the incoming end face 116 of the resin curing light oblique.

Further, as shown in FIG. 13B, another optical path conversion component 72 may be integrated with the output end surface 117. In addition, as shown in FIG.

Further, as shown in FIG. 13C, the optical path conversion component 73 is mounted on the mounting substrate 42, and the resin curing light is input while the photocurable resin is filled between the second waveguide core 114 and the optical path conversion component 73. , an optical path changing structure may be formed by the photocurable core 121 by emitting the light. At this time, it is desirable to form a highly reflective film 74 made of metal or dielectric on the optical path changing component in order to obtain a sufficient refractive index difference with the photocurable resin.

Alternatively, as shown in FIG. 13D, the second waveguide core 114 may be laid out so as to provide a loop circuit, and the end face for inputting and emitting the resin curing light may be arranged on the same end face. At this time, the resin curing light input core (optical fiber) and the output core (optical fiber) are arranged side by side in the width direction (Y direction).

Although illustration is omitted, in this embodiment, as in the first to sixth embodiments, for example, a configuration in which an output oblique end surface is formed in the optical circuit device, or a configuration in which an optical path conversion component is arranged may be employed. good.

In the embodiment of the present invention, when the resin curing light is reflected and made incident on the waveguide core due to the configuration of the oblique end face of the optical circuit device, the optical path changing part, etc., the reflection is total reflection or reflection with high reflectance. is desirable. It is sufficient that the incident resin curing light is reflected so as to be emitted with an intensity capable of curing the photocurable resin.

In the embodiments of the present invention, an example of the structure, dimensions, materials, etc. of each component is shown in the configuration of the optical circuit device, etc., but the present invention is not limited to this. Any material may be used as long as it exhibits the function of the optical circuit device and produces an effect.

The present invention relates to optical circuit devices, and can be applied to equipment and systems such as optical communication.

11 optical circuit device 111 waveguide substrate,
112 under clad 113 first waveguide core 114 second waveguide core 115 over clad 121 resin core 122 resin clad

Claims

in turn a waveguide substrate;
an undercladding;
a core through which resin curing light is guided;
An optical circuit device comprising an overcladding and
a resin core in which a photocurable resin is cured by being irradiated with the resin curing light;
a resin clad having a refractive index smaller than that of the resin core and disposed around the resin core;
the resin curing light is emitted from a core in which the resin curing light is guided at one end of the optical circuit device;
An optical circuit device, wherein the surface of the other end portion of the optical circuit device is inclined toward the waveguide substrate.
a mounting substrate having electrical contacts on its top surface;
2. The optical circuit device of claim 1, comprising a reflective structure disposed between the overcladding and the electrical contact of the optical circuit device.
in turn a waveguide substrate;
an undercladding;
a core through which resin curing light is guided;
An optical circuit device comprising an overcladding and
a resin core in which a photocurable resin is cured by being irradiated with the resin curing light;
a resin clad having a refractive index smaller than that of the resin core and disposed around the resin core;
the resin curing light is emitted from a core in which the resin curing light is guided at one end of the optical circuit device;
An optical circuit device, wherein a part of the surface of the optical circuit device is inclined toward a core side through which the resin curing light is guided.
in turn a waveguide substrate;
an undercladding;
a core through which resin curing light is guided;
An optical circuit device comprising an overcladding and
a resin core in which a photocurable resin is cured by being irradiated with the resin curing light;
a resin clad having a refractive index smaller than that of the resin core and disposed around the resin core;
the resin curing light is emitted from a core in which the resin curing light is guided at one end of the optical circuit device;
An optical circuit device, wherein an optical path converting component is connected to or located close to a core in the other end face of the optical circuit device through which the resin curing light is guided.
5. The optical circuit device according to claim 4, wherein the optical path conversion component is a mirror component.
A width of a core through which the resin curing light is guided in a region near the input portion of the resin curing light is wider than a width of a core through which the resin curing light is guided in a region other than the input portion near-by region. The optical circuit device according to any one of claims 1 to 5.
The optical circuit device according to any one of claims 1 to 6, wherein the resin core extends parallel to the longitudinal direction of the optical circuit core.
The optical circuit device according to any one of claims 1 to 7, wherein the resin core extends perpendicularly to the longitudinal direction of the optical circuit core.
1. The core through which the resin curing light is guided includes a first waveguide core and a second waveguide core optically coupled to the first waveguide core. 9. The optical circuit device according to any one of 8.