JPH11202145A - Optical module and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the optical module for a hybrid optical integrated circuit which has a sealing structure with superior economy and reliability and the manufacture thereof. SOLUTION: This optical module is embedded in resin 22 wherein an optical waveguide 11 provided on a substrate 12 is molded. In this case, a resin stopper 15 which prevents the resin 22 from flowing to a waveguide end surface is provided at an input/output end part while surrounding the optical waveguide 11 and substrate 12 and the end surface of the optical waveguide 11 is exposed to the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin-sealed optical module and a method for manufacturing the same, and more particularly to a hybrid optical integrated circuit having a sealing structure excellent in economy and reliability.

[0002]

2. Description of the Related Art In an optical integrated circuit in which an optical element such as an LD optically coupled to an optical waveguide is integrated on a substrate, a method of molding with a resin as in the case of a silicon semiconductor has been used in order to ensure reliability economically. Are being considered. For example, Terashima
Other authors, Proceedings of the 1997 IEICE General Conference C-3-
The 61 has an LD and a monitor PD mounted on a Si substrate,
There has been proposed a structure in which an optical fiber with a ferrule is placed in a V-groove formed in a Si substrate, fixed, and then the whole is sealed with an epoxy resin. An optical module similarly sealed with a resin is also reported in Ishii et al., "Proceedings of the 1997 IEICE General Conference C-3-62".

FIG. 9A is a sectional view of an optical module based on those proposals, and FIG. 9B is a perspective view thereof. In FIG. 9, reference numeral 01 denotes an optical fiber, 02 denotes a ferrule, 03 denotes a sealing resin, 04 denotes a transparent resin, 05 denotes an optical element, 06 denotes a V-grooved Si substrate, and 07 denotes an optical fiber holder. . In this conventional example, an optical fiber is used as an optical waveguide. The optical fiber 01 is a Si substrate 0
6 is bonded and fixed to the V groove by an optical fiber retainer 07, and optically coupled to an optical element. In the report example, an LD and a monitor PD are mentioned as the optical element 05. These optical elements 05 are wire-bonded to the lead frame 08 with gold wires via electrodes on the Si substrate 06.

The optical element 05 and the optical coupling portion between the optical element 05 and the optical fiber 01 are covered with a transparent resin 04 to protect the opaque sealing resin 03 from intrusion and stress. In the optical module thus formed, for example, a receptacle of an optical connector is used by being adhered to an end face.

[0005]

On the other hand, if a quartz-based planar lightwave circuit is used instead of an optical fiber as the optical waveguide, a high-performance optical circuit such as a branch circuit or a branching circuit can be easily realized. LD for transmission and PD for reception by branching
For example, an optical transceiver is configured by integrating the above. In this case, it is necessary to connect an optical fiber to the optical waveguide in order to take out the input and output to the outside. Usually, the optical fiber block is connected and fixed to the end of the optical waveguide by an adhesive. However, when attempting to mold the optical waveguide having this structure with a resin, the stress due to the contact of the mold during molding and the residual stress of the molding agent act on the optical fiber block, and as a result, the displacement between the optical fiber and the optical waveguide is caused. Occurs, and in the worst case, the optical fiber block comes off.

Accordingly, it has been desired to solve these problems and realize a sealing technique which enables economical resin sealing and enables highly efficient connection between an optical fiber and an optical waveguide. In other words, it has been desired to realize a sealing technique that enables economical resin sealing and enables highly efficient optical connection between an optical fiber and an optical waveguide.

An object of the present invention is to provide a resin-sealed optical module capable of highly efficient optical connection between an optical fiber and an optical waveguide by exposing an end face of the optical waveguide, and a method of manufacturing the same.

[0008]

According to a first aspect of the present invention, there is provided an optical module in which an optical waveguide provided on a substrate is embedded in a molded resin.
An optical module, wherein a resin stopper for preventing the resin from flowing into the waveguide end face is provided at an input / output end so as to surround the optical waveguide and the substrate, and the end face of the optical waveguide is exposed to the outside. suggest.

According to the first aspect of the present invention, in an optical module in which an optical waveguide provided on a substrate is embedded in a resin, a resin stopper is provided so as to surround the optical waveguide and the substrate. Can be prevented from covering the whole, and one end of the optical waveguide can be exposed to the outside. This makes it possible to perform active alignment of the input / output optical fibers with the optical module while sealing most of the optical module with resin, thereby realizing a highly efficient and highly reliable optical module. it can. Further, as a result, since the optical fiber can be arranged outside the molding material, it is possible to prevent the occurrence of the optical fiber position shift due to the stress of the molding material.

According to a second aspect, the resin stopper is a first aspect.
The present invention proposes an optical module, wherein the resin stopper is fixed to an optical waveguide and a substrate.

According to the second aspect, by fixing the resin stopper to the optical waveguide and the substrate with an adhesive or the like, flexibility in the construction method of the optical module can be obtained.

According to a third aspect, in the first or second aspect,
An optical module is proposed, wherein the resin stopper serves also as an optical fiber connection reinforcing member.

According to the third aspect, the resin stopper serves also as an optical fiber connection reinforcing member, so that an economical and highly efficient optical module can be realized.

According to a fourth aspect, in the first or second aspect,
An optical module is characterized in that the resin stopper serves also as a structure constituting an optical connector.

According to the fourth aspect, the resin stopper also serves as the structure constituting the optical connector, so that an economical and highly efficient optical module can be realized. In the conventional reports, the receptacle of the optical connector is bonded later, but the resin stopper also serves as the receptacle of the optical connector, so that the optical module can be realized more economically.

In a fifth aspect, in the first to fourth aspects,
The substrate provided with the optical waveguide is fixed on a lead frame, an optical element optically coupled to the optical waveguide is mounted on the substrate, and the lead frame is connected to an electrode on the substrate and / or an electrical wiring on the optical waveguide. An optical module characterized in that an optical element is electrically wired to the optical module.

According to the fifth aspect, the substrate is fixed to the lead frame, and electric wiring to the optical element mounted on the substrate is performed via the lead frame mounted with the substrate.
There is no need to separately provide an electrode or a pin for taking out an electric wiring separately, and an optical module can be realized more economically.

According to claim 6, in claim 1 to 5,
An optical element optically coupled to the optical waveguide is mounted on a substrate provided with the optical waveguide, and an optical element and an optical coupling portion between the optical element and the optical waveguide are covered with a transparent resin. We propose an optical module.

According to the sixth aspect, by covering the optical coupling portion between the optical waveguide and the optical element with a transparent resin, it becomes possible to use an opaque resin as a resin for sealing the whole, and the choice of resins is expanded. That is, it becomes possible to use a resin having high moisture resistance filled with an inorganic substance or the like, and the moisture resistance and reliability of the optical module are greatly improved. As the sealing resin having high moisture resistance, a resin that has been used in semiconductor encapsulation and has a proven track record can be used.

In a seventh aspect, in the first to sixth aspects,
An optical module is proposed, wherein an optical fiber is connected to an end face of the optical waveguide.

According to the seventh aspect, since the end face of the optical waveguide is exposed, it is possible to connect the optical fiber for input and output with high efficiency, and to provide a highly reliable and economical resin-sealed optical module. it can.

According to claim 8, in claims 1 to 4,
An optical module is provided in which resin stoppers are provided on both sides of the optical waveguide, and optical fibers are connected to each other.

According to the eighth aspect, the optical components such as the splitter and the multiplexing / demultiplexing circuit can be sealed with resin while the connection with the optical fiber can be performed with high efficiency, so that the reliability can be improved.

In a ninth aspect, in the first to fourth aspects,
An optical module is provided, wherein microcapillaries are provided on both sides of the end face of the optical waveguide, each being aligned with the core of the optical waveguide, and optical fibers are respectively connected to the microcapillaries.

According to the ninth aspect, the optical waveguide is sealed with a resin, and the resin stopper serving also as a structure constituting the optical connector is provided on the end face.
Highly reliable optical components can be configured.

According to a tenth aspect, in the first aspect, the resin stopper serves also as an optical fiber connection reinforcing member, and after the resin stopper is fixed to the optical waveguide and the substrate,
An optical module is proposed in which the end face is flush with the optical waveguide and connected to an optical fiber connection block.

According to the tenth aspect, by using both the resin stopper and the optical fiber connection reinforcing member, highly efficient connection with the optical fiber is possible without reducing the number of parts and increasing the number of processes. A highly economical resin-sealed optical module can be obtained.

According to the eleventh aspect, in the optical module in which the optical waveguide provided on the substrate is embedded in a resin,
A method for manufacturing an optical module is proposed, wherein a mold used for embedding with a resin contacts the resin stopper so that the optical waveguide and the substrate do not directly contact the mold.

According to the eleventh aspect, since the optical waveguide and the substrate do not come into direct contact with the resin sealing mold,
There is an advantage that generation of scratches on the optical waveguide and the substrate due to contact with the mold can be avoided.

[0030]

Embodiments of the present invention will be described below, but the present invention is not limited to these embodiments.

[Embodiment 1] The first embodiment of the present invention is an example in which a resin stopper is formed on an optical waveguide provided on a substrate and the substrate, and the substrate is sealed with a resin. FIG. 1A is a plan view of an example in which a resin stopper 2 is formed on an optical waveguide provided on a substrate, and FIG. 1B is a perspective view thereof. In addition,
In FIG. 1A, the lead frame is omitted. Further, the lead frame of FIG. 1B is shown in a cut form after the module is formed.

As shown in FIG. 1B, an optical waveguide 11 is formed on a substrate 12. The substrate 12 is bonded and fixed on the lead frame 13, and an adhesive, solder, or the like can be applied to this bonding as in a normal semiconductor production process. The reinforcing member 14 is bonded and fixed on the optical waveguide 11 with an adhesive or the like. Here, examples of the optical waveguide 11 include various optical waveguides such as quartz, polymer, and semiconductor. Examples of the substrate 12 include an Al substrate, a steel polyimide substrate, a ceramic substrate, a glass substrate, and the like, in addition to the Si substrate similar to the conventional example shown in FIG. Various metals generally used in semiconductor production can be applied to the lead frame 13. The reinforcing member 14 may be made of plastic, ceramic, or the like, in addition to glass.

In the present invention, the resin stopper 15 is preferably made of an organic material such as a thermoplastic resin, a thermosetting resin, or an elastomer. However, the present invention is not limited to this. Can be used. The resin stopper 15
May be formed by injection molding or grinding of a thermoplastic resin, and then fixed around the substrate 12, the optical waveguide 11, and the reinforcing member 14 by a fixing means such as an adhesive.

The notch 16 of the optical waveguide shown in FIG. 1A in this embodiment is a portion where the optical waveguide 11 is removed and the substrate 12 is exposed, and the optical element 17 is mounted. Have been. For example, as the optical element 17, LD and P
By mounting D and optically coupling to one end of the Y-branch waveguide as shown in FIG. 1A, an optical module for an optical transceiver can be configured.

FIG. 2 is a cross-sectional view when the optical waveguide with the resin stopper shown in FIG. 1 is set in a sealing mold (hereinafter referred to as "mold") 21 to perform resin sealing. is there. The injection hole of the sealing resin 22 is omitted. The optical coupling portion and the optical element 17 are protected by the transparent resin 23. The transparent resin 23
For example, a silicone resin having a small stress is suitable.
In the present invention, the sealing resin 22 may be an epoxy resin for transfer molding in addition to a liquid epoxy resin or a urethane resin, but the present invention is not limited to this. If a release agent is applied to the inside of the mold 21, the mold 21 can be easily removed after the sealing resin is cured.

The mold 21 is divided into upper and lower parts, for example.
A structure in which the lead frame 13 and the resin stopper 15 are sandwiched and fixed can be applied. In this case, only the lead frame 13 and the resin stopper 15 come into contact with the mold 21. The upper and lower molds 21 are pressurized and fixed using a fastening member such as a screw. The above-described sealing resin 22 is injected into such a mold 21 and is heated and cured at a predetermined temperature, whereby an optical module sealed with resin is obtained.

For comparison, FIG. 3 is a cross-sectional view of the optical module of the present embodiment at the time of sealing when the optical module is manufactured without the resin stopper 15. As shown in FIG. 3, when the resin stopper 15 is not provided, the mold 21 is directly connected to the substrate 12 and the reinforcing member 1.
4 would be touched. Upper and lower molds 2 during sealing
Since it is necessary to apply pressure to the base plates 21 and 21 to prevent the resin from leaking, the substrate 12 directly in contact with the mold 21 is required.
It can be understood that stress is applied to the reinforcing member 14 and the risk of breakage. On the other hand, as shown in FIG. 2, the resin stopper 15 is interposed between the mold 21 and the substrate 12 or the reinforcing member 14, thereby absorbing the stress and reducing the risk of breakage. .

In the resin-sealed optical module obtained in the present embodiment, since the end face of the optical waveguide 11 is exposed, the input and output optical fibers are highly accurately aligned by the active alignment method, and then bonded. Can be fixed.

FIG. 4 is a sectional view of a module in which an optical fiber 24 is adhered and fixed to the resin-sealed optical module obtained in this embodiment. The glass block 25 for fiber connection has a V-groove, and the optical fiber 24 is interposed and fixed.
This is for reinforcing the fiber connection part.

In this embodiment, for example, the optical element 17
If one of the two is a laser diode, a driving current is passed through the laser diode, and light emitted from the end face of the optical waveguide 11 is monitored by an optical sensor connected to the other end of the optical fiber 24, while the optical fiber 24 and the optical waveguide 11 are connected. Positioning can be performed. If an ultraviolet-curable adhesive is applied to the end face of the optical waveguide 11 in advance, it can be bonded and fixed by irradiating ultraviolet rays after positioning. In addition, by cutting the connection portion obliquely as shown in FIG. 4, reflection at the interface can be suppressed.

As described above, by fixing the mold with the resin stopper fixed to the optical waveguide and the substrate, the fragile optical waveguide and the substrate do not come into contact with the mold and the end faces of the optical waveguide are exposed to the outside. It can be sealed with resin, and as a result, a highly reliable and economical resin-sealed optical module that can be connected to optical fibers with high efficiency can be obtained.

[Second Embodiment] A second embodiment is an example in which a resin stopper is used also as an optical connector, and FIG. 5 is a sectional view. In the present embodiment, the resin stopper 31 also serves as the receptacle of the optical connector, and is fixed around the substrate 12, the optical waveguide 11, and the reinforcing member 14 with an epoxy adhesive as in the first embodiment. The end face of the optical waveguide is vertically cut and polished, and the microcapillary 32 is aligned and fixed to the core of the optical waveguide by an active alignment method before resin sealing. The plug 33 of the optical connector to which the optical fiber 24 is attached is connected to the receptacle 31.
The optical fiber 24 is engaged with the microcapillary 3
2 is inserted at the center.

As in the first embodiment, the mold is
1 and the lead frame 13 are aligned and fixed, resin is injected, heated and cured to obtain a desired resin-sealed optical module.

As described above, since the resin stopper and the optical connector are also used, a resin-sealed optical module with an optical connector can be obtained without increasing the number of processes.

Embodiment 3 Embodiment 3 is an example in which resin stoppers are provided at both ends of an optical module and optical fibers are connected to both ends, and FIG. 6 is a sectional view. Optical waveguide 11
Is, for example, a splitter or a multiplexing / demultiplexing circuit. In the present embodiment, the resin stoppers 15 are fixed to both ends of the optical waveguide 11, respectively. Also in the present embodiment, a mold (not shown) is fixed so that two resin stoppers 15 are sandwiched, and a resin is injected, heated, and cured to obtain a target resin-sealed optical module. . In FIG. 6, the interface between the optical waveguide and the substrate and the connection-reinforcing glass block 34 is cut and polished diagonally so as to suppress the return of reflected light at the bonding interface after connection.

In this way, the optical components such as the splitter can be sealed with the resin while the connection with the input / output optical fiber can be performed with high efficiency, so that the reliability can be improved.

In the present embodiment, the connection with the optical fiber is exemplified by active alignment using a glass block, but an example in which a resin stopper is used also as an optical connector can be cited. FIG. 7 shows a cross-sectional view thereof. In the present embodiment, the resin stopper 31 also serves as the receptacle of the optical connector as in the second embodiment. In this example, the optical waveguide is sealed with resin, and an optical connector is already connected to the end face, so that an optical component with a very compact configuration and high reliability can be configured.

Fourth Embodiment A fourth embodiment is an example in which a resin stopper is used also as an optical fiber connection reinforcing member, and FIG. 8 is a sectional view. An optical waveguide 11 is formed on a substrate 12 and an optical element 17 optically coupled to the optical waveguide 11 is mounted thereon in the same manner as in the first embodiment.
3 protected. However, the optical fiber connection reinforcing member 14 shown in the first embodiment is also used as the resin stopper 35 in the present embodiment. After the resin stopper 35 is fixed to the optical waveguide 11 and the substrate 12,
Is polished so that the end faces are flush with each other. The same material as that described in Embodiment 1 can be applied to the resin stopper 35 which also serves as a reinforcing member. Thereafter, similarly to the first embodiment, the optical module is fixed to a mold and sealed with a resin to obtain an optical module.

As described above, by using both the resin stopper and the optical fiber connection reinforcing member, highly efficient connection with the optical fiber is possible without reducing the number of parts and increasing the number of processes, and the reliability and economy are improved. , A resin-sealed optical module having a high

[0050]

As described above, according to the first to fourth aspects of the present invention, in an optical module in which an optical waveguide provided on a substrate is embedded in a resin, a resin stopper is provided on a part of the optical waveguide and the substrate. With this arrangement, at least one end of the optical waveguide is exposed to the outside, and an optical fiber can be connected thereto by an active alignment method, so that a highly reliable resin-sealed optical module with small connection loss can be obtained. This resin stopper can be bonded and fixed to the optical waveguide and the substrate, and can also serve as an optical connector or an optical fiber connection reinforcing member. As a result, a resin-sealed optical module having excellent connectivity can be obtained without increasing the module manufacturing cost.

According to the fifth and sixth aspects of the present invention, the substrate is fixed on the lead frame and the electrical wiring is performed,
An optical waveguide having an optical element optically coupled to the optical waveguide can be easily sealed with a resin while maintaining the connectivity with the optical fiber, so that a highly reliable optical module can be obtained. At this time, the optical element and the optical coupling section can be protected from the sealing resin by being covered with the transparent resin.

According to the seventh aspect of the present invention, since the end face of the optical waveguide is exposed, highly efficient connection with the input / output optical fiber is possible, and the resin sealing with high reliability and economy is achieved. An optical module can be provided.

According to the invention of claim 8, it is possible to improve the reliability by sealing the optical parts such as the splitter and the multiplexing / demultiplexing circuit with the resin while the connection with the optical fiber can be performed with high efficiency. it can.

According to the ninth aspect of the present invention, the optical waveguide is sealed with a resin, and the resin stopper serving also as a structure constituting the optical connector is provided on the end face. High optical components can be configured.

According to the tenth aspect, by using both the resin stopper and the optical fiber connection reinforcing member, highly efficient connection with the optical fiber is possible without reducing the number of components and increasing the number of processes. A highly economical resin-sealed optical module can be obtained.

According to the eleventh aspect of the present invention, since the mold is fixed by the resin stopper, the fragile optical waveguide and the substrate are prevented from directly contacting the mold. Deterioration such as cracks in the optical waveguide or the substrate can be prevented, and a highly reliable optical module can be realized.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a resin-sealed optical module of the present invention. (A) is a plan view, (b) is a perspective view.

FIG. 2 is a cross-sectional view of the resin-sealed optical module according to the first embodiment of the present invention when it is sealed.

FIG. 3 is a cross-sectional view of the present invention when resin sealing is performed without using a resin stopper.

FIG. 4 is a sectional view of a resin-sealed optical module obtained by the first embodiment of the resin-sealed optical module of the present invention, in which an optical fiber is adhered and fixed to the resin-sealed optical module.

FIG. 5 is a sectional view showing a second embodiment of the resin-sealed optical module of the present invention.

FIG. 6 is a sectional view showing a third embodiment of the resin-sealed optical module of the present invention.

FIG. 7 is a cross-sectional view showing a third embodiment of the resin-sealed optical module of the present invention, in which the resin stopper also serves as an optical connector.

FIG. 8 is a sectional view showing a fourth embodiment of the resin-sealed optical module of the present invention.

FIG. 9 is a cross-sectional view showing a configuration of a conventional resin-sealed optical module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Optical waveguide 12 Substrate 13 Lead frame 14 Member for connection reinforcement 15 Resin stop 16 Notch of optical waveguide 17 Optical element 18 Core of optical waveguide 21 Sealing mold 22 Sealing resin 23 Transparent resin 24 Optical fiber 25 Optical fiber Glass block for connection reinforcement 31 Resin stopper (also used as receptacle) 32 Microcapillary 33 Plug for optical connector 34 Glass block for connection reinforcement 35 Resin stopper also used as optical fiber connection reinforcement member 02 Ferrule 01 Optical fiber 02 Ferrule 03 Sealing resin 04 Transparent resin 05 Optical element 06 Si substrate with V-groove 07 Optical fiber holder 08 Lead frame

Continued on the front page (72) Inventor Akira Morinaka 3-19-2 Nishi Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Shuichiro Asakawa 3-9-1-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Inside Telegraph and Telephone Co., Ltd. (72) Koji Sato, Inventor 3-192-2 Nishi Shinjuku, Shinjuku-ku, Tokyo Japan Inside Telegraph and Telephone Co., Ltd. Telegraph and Telephone Corporation

Claims (11)

[Claims] In an optical module in which an optical waveguide provided on a substrate is embedded in a molded resin, a resin stopper for preventing the resin from flowing into an end face of the waveguide surrounds the optical waveguide and the substrate. An optical module provided at an input / output end, wherein an end face of an optical waveguide is exposed to the outside. 2. The optical module according to claim 1, wherein the resin stopper is fixed to the optical waveguide and the substrate. 3. The optical module according to claim 1, wherein the resin stopper serves also as an optical fiber connection reinforcing member. 4. The optical module according to claim 1, wherein the resin stopper serves also as a structure constituting an optical connector. 5. The substrate according to claim 1, wherein the substrate on which the optical waveguide is provided is fixed on a lead frame, an optical element optically coupled to the optical waveguide is mounted on the substrate, and an electrode on the substrate and / or Alternatively, the optical module is characterized in that the optical element is electrically wired to the lead frame via the electrical wiring on the optical waveguide. 6. The optical device according to claim 1, wherein an optical element optically coupled to the optical waveguide is mounted on a substrate provided with the optical waveguide, and an optical element and an optical coupling portion between the optical element and the optical waveguide are transparent. An optical module characterized by being covered with a suitable resin. 7. The optical module according to claim 1, wherein an optical fiber is connected to an end face of the optical waveguide. 8. The optical module according to claim 1, wherein resin stoppers are provided on both sides of the optical waveguide, and optical fibers are respectively connected. 9. The microcapillary according to claim 1, further comprising a microcapillary aligned with a core of the optical waveguide on both sides of the end face of the optical waveguide, and an optical fiber connected to the microcapillary. An optical module characterized by the above-mentioned. 10. The optical fiber according to claim 1, wherein the resin stopper serves also as an optical fiber connection reinforcing member, and after fixing the resin stopper to the optical waveguide and the substrate, the end face is flush with the optical waveguide. An optical module characterized by being connected to a fiber connection block. 11. In an optical module in which an optical waveguide provided on a substrate is embedded in a resin, a mold used when embedding with a resin contacts the resin stopper, so that the optical waveguide and the substrate directly contact the mold. A method for manufacturing an optical module, comprising: