JP2018194802A - Optical module and method for manufacturing the same - Google Patents

Abstract

To provide an optical module having resistance to high power light and heat resistance, and a method for manufacturing the same.SOLUTION: An optical module 100 comprises: an optical fiber 101; a planar light wave circuit 102; a fiber block 103 having the optical fiber 101 inserted and fixed; a UV curable resin adhesives layer 104 for bonding and fixing the fiber block 103 and the planar light wave circuit 102; a glass layer 105 for bonding and fixing the fiber block 103 and the planar light wave circuit 102. The UV curable resin adhesives layer 104 is provided in a portion not passing light inputted or outputted between the optical fiber 101 and the planar light wave circuit 102, between the connection end surfaces of the fiber block 103 and the planar light wave circuit 102, and the glass layer 105 is provided in a portion passing light inputted or outputted between the optical fiber 101 and the planar light wave circuit 102, between the connection end surfaces.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an optical module in which a planar lightwave circuit and an optical fiber are optically connected, and a manufacturing method thereof, which is resistant to high-energy light such as visible light used for optical communication and optical sensing.

  In recent years, not only the spread of smartphones but also the expansion of services using IoT (Internet of Things) has led to a remarkable increase in communication traffic. One of the components that support this large-capacity optical communication is a planar lightwave circuit (PLC). A PLC is actually used in a current communication network, and a splitter that branches light, an optical switch that switches a path of an optical signal, and a laser and a modulator that serve as a light source are also realized in a broad sense. The PLC is composed of a quartz material, a silicon material, a semiconductor material, or the like. A PLC is usually not used alone, but in most cases is used by coupling input / output light in the PLC to an optical fiber.

  An example of a method for connecting a PLC and an optical fiber will be described with reference to FIG. FIG. 1 shows a laser light source (LD) 1, an optical fiber 2 connected to the LD 1, a PLC 3 that propagates and outputs light input from the optical fiber 2, and an optical fiber 2 for fixing the optical fiber 2 to the PLC 3. An optical module comprising a fiber block 4 is shown. A photodiode (PD) 5 that receives light output from the PLC 3 is connected to an optical fiber 6, and the PLC 3 and the fiber block 4 are bonded together with a UV curable resin adhesive 7.

  The fiber block 4 is installed at the tip of the optical fiber 2 in order to obtain a bonding area with respect to the PLC 3. As the fiber block 4, a glass member such as a V-groove substrate or a microcapillary is generally used.

  The positions of the optical fiber 2 and the PLC 3 are fixed to each other after the PLC 3 and the optical fibers 2 and 6 are fixed to the fine motion aligning device, and the fiber block 4 in which the optical fiber 2 is inserted is brought close to the PLC 3. After the agent 7 is applied to the connection gap, it is determined by adjusting with submicron order accuracy so that the light receiving intensity of the PD 5 is maximized. Thereafter, the optical fiber 2 and the PLC 3 are fixed by irradiating UV light to cure the UV curable resin adhesive 7.

  Here, if necessary, an optical fiber is directly connected to the output end of the PLC 3 instead of the PD 5, and the output light intensity is measured by connecting the optical fiber to a power meter, and the output light measured by the power meter. The positions of the optical fiber 2 and the PLC 3 may be adjusted by a fine alignment device so that the intensity becomes maximum. Further, not only the connection between the optical fiber 2 and the PLC 3, but another PLC and another PLC may be connected.

  As described above, a UV curable resin adhesive is generally used for connection between the optical fiber and the PLC (see, for example, Patent Document 1). The following three points can be cited as advantages of using the UV curable resin adhesive in the optical connection between the optical fiber and the PLC.

  The first advantage is that when a UV curable resin adhesive is used, the optical fiber can be fixed to the PLC with high relative positional accuracy. If optical connection is made using a thermosetting adhesive, the relative position between the optical fiber and the PLC is changed by the thermal expansion of the jig for pressing and fixing the fiber block when heated to cure the thermosetting adhesive. It is difficult to fix the optical fiber accurately because the optical fiber moves from the fine alignment device. In addition, when a room temperature curable adhesive is used, it takes time for the room temperature curable adhesive to cure, and the relative position of the jig itself cannot be maintained during curing. Therefore, it is expected that the relative position between the optical fiber and the PLC in the optical connection is shifted, and the optical fiber moves from the fine alignment device.

  On the other hand, since the UV curing resin adhesive has a short curing time, it can be connected while maintaining the relative position between the optical fiber and the PLC. Therefore, in the case of using the UV curable resin adhesive, the optical fiber can be connected to the PLC without moving from above the fine movement aligning device, so that an optical connection with a good relative position accuracy is possible.

  The second advantage is that the optical fiber and the PLC can be connected with high production throughput when considering the mass productivity of the device including the PLC.

  Since the optical connection process using the fine motion aligning device is performed for each sample, if the occupation time of the fine motion aligning device for each sample is long, the production throughput deteriorates. In order to increase the throughput, parallel processing of the optical connection process can be considered. However, the LD, power meter, fine adjustment device, etc. used for the optical connection are not inexpensive, so there is a capital investment by preparing a plurality of these. There is a problem of increasing.

  In this respect, since the UV curable resin adhesive is cured in about several minutes by being irradiated with UV light, the curing time is much shorter than that of a room temperature curable adhesive or a two-component adhesive that is cured by being left for several hours. . Therefore, by using the UV curable resin adhesive, an optical connection with a good production throughput is possible.

  The third advantage is that since the UV curable resin adhesive is a resin, the refractive index of the UV curable resin adhesive, which greatly affects the optical connection loss, is adjusted to match the refractive index of the core layer at the outgoing end face of the PLC. Is that you can.

  When the optical fiber and the PLC are optically connected through a space using a lens, AR (anti-reflection) processing is performed on the emission end face of the PLC in order to eliminate the influence of reflection, but this increases the cost. Connected. On the other hand, a low-loss optical connection can be realized at low cost by adjusting the refractive index using a UV curable resin adhesive.

  Due to such advantages, in many cases, a UV curable resin adhesive is used for optical connection between the optical fiber and the PLC.

JP 2014-048628 A

  Up to now, PLC has been mainly used as a component for optical communication, but recently, the application destination is expanding to an optical probe type sensor or the like. Further, since the PLC has a small number of alignment steps and is strong against vibration, it is also expected to be used as an optical component in a projector that multiplexes / demultiplexes RGB three primary color light sources.

  As described above, with the expansion of application destinations of PLCs, not only the light in the communication wavelength band but also the light in the visible light wavelength band is used as the light propagated to the PLC. Therefore, it is necessary to take measures for propagating visible light not only to components constituting the optical module, such as PLC and optical fiber, but also to optical connection portions connecting them.

  As described above, in the conventional optical connection technology, a UV curable adhesive is used for the optical connection portion. However, this UV curable resin adhesive is known to absorb high energy visible light and deteriorate. This phenomenon occurs by propagating high power light of several mW class to the UV curable resin adhesive even in the communication wavelength band.

  FIG. 2 shows another example of a method for connecting a PLC and an optical fiber. In the configuration shown in FIG. 2, a portion where light passes between the PLC 3 and the fiber block 4 is a gap. Thus, in order to avoid the deterioration of the UV curable resin adhesive, only the portion where the light does not pass between the PLC 3 and the fiber block 4 is fixed with the UV curable resin adhesive 7, and the portion where the light passes is made a gap. Connection methods may be taken. However, this connection method has a problem that a dust collection phenomenon occurs in a gap portion through which light passes and connection loss increases.

  Furthermore, when PLC is used for communication, it is usually used at room temperature. However, when it is used as an optical sensor, even severer temperature conditions, such as in the engine room of a car or at high geothermal temperatures in a mine, etc. Use in an environment of about 200 ° C at all times is also assumed. However, since the UV curable resin adhesive generally used for optical connection does not have a heat resistance of 85 ° C. or higher, an optical module optically connected using such a UV curable resin adhesive is 200. When placed in an environment of about ° C., the UV curable resin adhesive is softened, the optical connection position is shifted, and the connection loss increases.

  Recently, UV curable resin adhesives with high heat resistance that do not soften even when heated at a high temperature of about 200 ° C. have appeared. However, when an optical module optically connected using such a highly heat-resistant UV curable resin adhesive is placed in an environment of about 200 ° C., the UV curable resin adhesive is not softened by heat, but depending on factors such as humidity. The UV curable resin adhesive is deteriorated with time, and the position of the phase difference between the PLC and the optical fiber is shifted to increase the connection loss. For this reason, since an optical connection having heat resistance has not been realized conventionally, an optical module in which a PLC and an optical fiber are optically connected cannot be used in a high temperature environment.

  As described above, in the conventional optical connection technology, when high energy light such as visible light is propagated or subjected to severe temperature conditions, the UV curable resin adhesive used for the optical connection portion is deteriorated. There is a problem that a stable and long-term reliable optical connection cannot be realized.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical module that is resistant to high-power light and is heat resistant, and a method for manufacturing the same.

  An optical module according to an aspect of the present invention includes one or more optical fibers, a planar lightwave circuit that is optically connected to the one or more optical fibers, and a fiber in which the one or more optical fibers are inserted and fixed. An optical module comprising a block, a UV curable resin adhesive layer for bonding and fixing the fiber block and the planar lightwave circuit, and a glass layer for bonding and fixing the fiber block and the planar lightwave circuit. The UV curable resin adhesive layer allows light input or output between the one or more optical fibers and the planar lightwave circuit to pass between the connection end surfaces of the fiber block and the planar lightwave circuit. The glass layer is provided between the connection end faces, and the glass layer allows light input or output between the one or more optical fibers and the planar lightwave circuit to pass therethrough. Characterized in that it is provided in a portion.

  An optical module manufacturing method according to an aspect of the present invention is a method for manufacturing an optical module in which one or a plurality of optical fibers inserted and fixed in a fiber block and a planar lightwave circuit are optically connected. The step of adjusting the connection position between the optical fiber inserted into and fixed to the fiber block and the planar lightwave circuit using a core device, and between the connection end faces of the fiber block and the planar lightwave circuit, Or a step of applying a UV curable resin adhesive to a portion where light input or output does not propagate between a plurality of optical fibers and the planar lightwave circuit, and irradiating the UV curable resin adhesive with UV light, Bonding and fixing the fiber block and the planar lightwave circuit, and between the connection end surfaces, the one or more optical fibers and the planar lightwave circuit Is input or the light output was filled with glass precursor materials in a portion propagating between, characterized in that it comprises the steps of: curing the glass precursor material by liquid phase synthesis.

  According to the present invention, it is possible to provide an optical module that is resistant to high-power light and is heat-resistant, and a method for manufacturing the same, and greatly contributes to the expansion of PLC application destinations.

It is a figure for demonstrating the prior art example of the method of connecting PLC and an optical fiber. It is a figure for demonstrating the other prior art example of the method of connecting PLC and an optical fiber. It is a figure which illustrates the optical module which concerns on Example 1 of this invention. It is a perspective view of the state before connecting PLC and a fiber block in the optical module which concerns on Example 1 of this invention. It is a figure which shows the measurement system of high power tolerance about the optical module which concerns on this invention. It is a figure which shows the measurement result of the time-dependent loss fluctuation | variation of the optical module which concerns on this invention. It is a figure which shows the result of the reliability test of the optical module which concerns on this invention. It is a figure which shows the result of the heat resistance test of the optical module which concerns on this invention. It is a figure which illustrates the optical module which concerns on Example 3 of this invention.

Example 1
FIG. 3 is a top cross-sectional view of the optical module according to Embodiment 1 of the present invention. 3, the optical fiber 101, the PLC 102 that is optically connected to the optical fiber 101, the fiber block 103 into which the optical fiber 101 is inserted and fixed, and the optical fiber 101 and the PLC 102 between the connection end faces of the PLC 102 and the fiber block 103. Light that is input / output between the optical fiber 101 and the PLC 102 passes between the UV curable resin adhesive layer 104 that bonds and fixes a portion through which light input / output does not pass and the connection end surface between the PLC 102 and the fiber block 103. An optical module 100 having a glass layer 105 for adhering and fixing a portion to be fixed is shown. As shown in FIG. 3, the fiber block 103 is provided with an adhesive dam groove 106.

  The glass layer 105 is produced by a liquid phase synthesis method. The liquid phase synthesis method is, for example, a sol-gel method in which a liquid raw material is polymerized to form a glass by curing at room temperature or by baking, and is a kind of sol-gel method. A polysilazane method in which polysilazane is cured by standing or baking at room temperature to generate glass, or a liquid phase precipitation method in which liquid raw material is cured by hydrolysis to generate glass can be used.

Here, in this embodiment, polysilazane is used as the precursor material of the glass layer 105. Hereinafter, polysilazane will be briefly described. Polysilazane is an inorganic polymer material having SiH ₂ NH as a basic unit, and is cured by reacting with water to form a high-purity silica film. The cured silica film is colorless and transparent, has no absorption edge with respect to visible light, and has high transparency. Moreover, since polysilazane becomes inorganic SiO ₂ after curing, it has resistance to high-energy light, and further has heat resistance of about 1000 ° C. Furthermore, since polysilazane is a one-pack type solution, it can be easily filled into minute gaps on the connection end faces.

  In order to lower the conversion temperature to silica, polysilazane is often added as a dopant with an amine-based catalyst that promotes the reaction with dehydrogenation and oxidation catalyst Pb compound and moisture. The curing rate and reaction rate of polysilazane vary depending on the dopant contained in polysilazane, the curing temperature, and the curing environment such as curing in a high humidity atmosphere.

As a precursor material of the glass layer 105 produced by the liquid phase synthesis method, for example, silicon alkoxide Si (OC ₂ H ₅ ) _{4 in} addition to an inorganic polymer material having SiH ₂ NH as a basic unit such as polysilazane. Can be used, and those mainly composed of hydrogen silicofluoride (H ₂ SiF ₆ ) can be used.

  FIG. 4 is a perspective view of a state before connecting the PLC and the fiber block in the optical module according to Embodiment 1 of the present invention. For the sake of simplicity, FIG. 4 shows a configuration when a fiber block is connected only to the output side of the PLC.

  As shown in FIG. 4, the PLC 102 can have an embedded waveguide structure in which a core layer is embedded with a cladding layer on a Si substrate. The input / output ends of the PLC 102 are connected by an S-shaped bending waveguide formed by forming a core layer in an S-shape.

  Hereinafter, a method for manufacturing an optical module according to the present invention will be described. The PLC 102 can be manufactured, for example, by the following procedure. An under cladding layer made of quartz glass having a thickness of 20 μm and a core layer made of quartz glass having a thickness of 2 μm whose refractive index has been increased by Ge doping are sequentially deposited on the Si substrate. The core layer is formed into an optical waveguide pattern by a general exposure development technique and etching technique. Then, after forming an optical waveguide by laminating an overcladding layer made of quartz glass by 15 μm, the wafer is cut, and a 5.0 × 10.0 mm size chip is cut out to produce a quartz PLC 102 did. Quartz-based PLC 102 has a heat-resistant temperature exceeding 500 ° C.

  As the fiber block 103, for example, a V-groove substrate or a microcapillary can be used. The fiber block 103 can be manufactured by the following procedure in an example using a V-groove substrate.

  A V-groove for fixing a fiber having a diameter of 125 μm is formed by machining on a glass plate having a thickness of 1 mm and a size of 5 × 5 mm. The optical fiber 101 is set on the V-groove substrate on which the V-groove is formed, and the optical fiber 101 set on the V-groove substrate is sandwiched between glass plates having a thickness of 1 mm, 5 mm × 3 mm. The two glass plates and the optical fiber 101 sandwiched between these glass plates are bonded with a UV curable resin adhesive, fixed by irradiating with UV light, and then the end face is polished. Adhesive damming grooves 106 having a width of 150 μm and a depth of 500 μm are formed on the connection end face of the fiber block 103 assembled in this way at two locations on the left and right sides from the central portion of the connection end face.

  By forming the adhesive damming groove 106 in this way, it is possible to prevent the UV curable resin adhesive from entering the light passing portion on the connection end face. Therefore, it is possible to bond and fix the fiber block 103 and the PLC 102 while providing the UV curable resin adhesive layer 104 only in the portion where light does not pass on the connection end face and providing the glass layer 105 only in the light passing portion. . The adhesive blocking groove 106 may be, for example, a width of 100 μm or more and a depth of 100 μm or more.

  Next, after fixing the PLC 102 and the fiber block 103 to the fine-motion aligning device and adjusting the connection position with the connection end surface of the PLC 102 and the fiber block 103 separated by about 1 μm, the UV curable resin adhesive is applied between the connection end surfaces. Apply to the part where light does not pass through. At this time, the UV curable resin adhesive tends to spread over the entire connection end surface due to capillary action, but the UV curable resin adhesive is dammed by the adhesive damming groove 106, and the UV curable resin is bonded to the light passing portion of the connection end surface. The adhesive does not reach. Thereafter, the UV curable resin adhesive layer 104 is formed by irradiating and curing the UV curable resin adhesive spread on the connection end surface between the PLC 102 and the fiber block 103 by irradiating the UV light. Glue and fix.

  After removing the bonded PLC 102 and the fiber block 103 from the fine adjustment device, the polysilazane is hardened by filling the gap in the light passage portion between the connection end faces with polysilazane and leaving it at room temperature for 12 hours. The layer 105 is formed in the light passage portion. As described above, the optical module 100 according to Example 1 of the present invention was manufactured.

  The connection loss was evaluated for the optical module 100 according to Example 1 of the present invention thus manufactured. FIG. 5 shows a high power tolerance measurement system for the optical module 100 according to the first embodiment. As shown in FIG. 5, light having a wavelength of 405 nm is incident on the input end of the optical module 100 from the LD 110, and the output power of the light emitted from the output end of the optical module 100 is measured with the power meter 120.

  The insertion loss of the entire optical module 100 was 3.0 dB. Since the transmission loss of the PLC 102 is estimated to be 1.0 dB from the existing measurement, the connection loss at the two input / output ends is considered to be 1.0 dB, respectively.

  On the other hand, in the measurement system shown in FIG. 5, the connection loss was 1.0 dB when the connection loss was measured in the same manner using a conventional optical module having a light passage portion as a gap instead of the optical module 100. . Therefore, it was confirmed that even if polysilazane was filled in the light passage part, there was no problem in light transmission and a connection with little loss was realized.

  FIG. 6 shows a result when the loss variation of the optical module 100 according to the first embodiment when light with a wavelength of 405 nm and 20 mW is incident is continuously measured for 2000 hours. As shown in FIG. 6, in the optical module 100 according to Example 1, it was found that the output power did not change at 3 dB even after 2000 hours.

  On the other hand, when the connection loss of the conventional optical module shown in FIG. 2 in which the light passage portion is a gap is measured in the same manner, the output power deteriorates in about 100 hours. As described above, it has been confirmed by analysis that the dust is collected in the gap due to the dust collecting effect, and the output power is deteriorated by increasing the transmission loss.

  Next, FIG. 7A shows a temporal change in connection loss when the optical module 100 according to Example 1 of the present invention was subjected to a high temperature and high humidity test at 85% humidity and 85 ° C. for 2000 hours. FIG.7 (b) shows the temporal change of the connection loss when the heat cycle test of -40 degreeC-70 degreeC is done.

  As shown in FIG. 7A, in the optical module 100 according to Example 1 of the present invention, it was found that the output power did not change at 3 dB even after 2000 hours passed under high temperature and high humidity conditions. Moreover, as shown in FIG.7 (b), in the optical module 100 which concerns on Example 1 of this invention, even when it is a case where a -40 degreeC-70 degreeC heat cycle is given, output power does not change at 3 dB. I understood that. Therefore, in the optical module 100 according to Example 1 of the present invention, the light propagation characteristics did not deteriorate with time.

  Therefore, from the results shown in FIGS. 7A and 7B, it was found that the optical module 100 according to Example 1 of the present invention using polysilazane can withstand a reliability test. From this, when the optical fiber 101 and PLC102 were optically connected using polysilazane like a present Example, it was shown that the optical connection resistant to the high energy light of a visible region is possible.

  For the optical module 100 according to Example 1, the heat resistance of the optical connection portion was evaluated. FIG. 8 shows connection loss when the optical module 100 according to Example 1 is heated at 100 ° C., 200 ° C., and 300 ° C. for 1 hour at room temperature. In FIG. 8, using a measurement system similar to the measurement system shown in FIG. 5, light having a wavelength of 1550 nm is incident on one optical fiber 101 from the LD 110, and the output power of the light output from the other optical fiber 101 is expressed as power. Connection loss was evaluated by measuring with the meter 120. As shown in FIG. 8, it was shown that the connection loss does not change even if the optical module 100 according to Example 1 is continuously heated at a high temperature of 100 ° C. to 300 ° C.

  Thus, in the present invention, the UV curable resin adhesive constituting the UV curable resin adhesive layer 104 is used for temporarily fixing the connection position on the fine alignment device, and then the glass layer 105 is formed. To fix the connection position. Therefore, even if the UV curable resin adhesive layer 104 is deteriorated due to heat, the glass layer 105 can secure the connection position, connection strength, transparency, and reliability, so that it has heat resistance that can withstand even in a high temperature environment at all times. Connection is feasible.

  When considering the mass productivity of the manufacturing method of the optical module 100 according to the first embodiment of the present invention, in the manufacturing method of the optical module 100 according to the first embodiment, a portion through which light does not pass is fixed by the UV curable resin adhesive layer 104. In addition, since the light passage portion is filled with the glass precursor material, the glass precursor material is filled and cured at room temperature for a long time, compared with the conventional optical module manufacturing method as shown in FIG. The manufacturing process increases as much as it is made.

  However, this filling step is not a step of performing each sample using a fine alignment device, but it is sufficient to fill and cure the glass precursor material together on the connection end faces of many optical modules. The property is not greatly reduced.

  Therefore, the manufacturing method of the optical module 100 according to the first embodiment of the present invention is resistant to high energy light and has heat resistance while taking advantage of the optical connection using the conventional UV curable resin adhesive. Optical connection was realized. Therefore, the present invention greatly contributes to the expansion of PLC application destinations.

  In the first embodiment, for the sake of simplification, a configuration in which one optical fiber 101 is connected to each of the input and output ends is illustrated. A plurality of V-grooves for inserting and fixing the optical fiber 101, a plurality of optical waveguides formed in the PLC 102, and a plurality of optical fibers 101 connected to the input / output ends of the optical waveguide 101, respectively. The same applies to Example 2 below.

(Example 2)
Hereinafter, an optical module according to Embodiment 2 of the present invention will be described. In the optical module according to the second embodiment, the UV curable resin adhesive that does not soften even when heated at about 200 ° C. is used as the UV curable resin adhesive constituting the UV curable resin adhesive layer 104 that adheres a portion through which light does not pass. And the glass precursor material is cured by heating to form the glass layer 105.

  It is known that when a glass precursor material such as polysilazane is heated, the reaction with oxygen and water proceeds faster, and the time required for curing can be shortened than when the glass precursor material is left at room temperature. In the optical module according to the second embodiment, a glass precursor is used by using a UV curable resin adhesive that does not soften even when heated at 200 ° C. or higher as the UV curable resin adhesive constituting the UV curable resin adhesive layer 104. It is possible to form the glass layer 105 by curing the glass precursor material by heat treatment after filling the material. Therefore, according to the optical module according to the second embodiment, the curing time can be significantly shortened compared to the first embodiment in which polysilazane is cured by being left at room temperature for 12 hours, thereby realizing an improvement in mass production throughput. It becomes possible.

  In Example 2, the PLC 102 and the fiber block 103 were used except that a UV curable resin adhesive that does not peel or deteriorate even when heated at 200 ° C. was used as the UV curable resin adhesive used when assembling the fiber block. 1 was prepared in the same procedure. Further, in Example 2, a UV curable resin adhesive that does not soften even when heated at 200 ° C. for 1 hour is used as a UV curable resin adhesive used for connection of a portion where light does not pass on the connection end surface, and 200 ° C. as polysilazane. Except for using a material that can be cured in 1 hour when heated at, and curing polysilazane by heating at about 200 ° C. for 1 hour without filling it for 12 hours at room temperature after filling with polysilazane. These were connected in the same procedure as in Example 1.

  When the connection loss of the optical module according to Example 2 manufactured in this way was evaluated, the connection loss was 1.0 dB, which was the same as that of Example 1. In addition, in order to evaluate the high power resistance of the optical connection portion, light having a wavelength of 405 nm and 1 mW was transmitted through the optical module for 2000 hours, but the output power did not vary. When the heat resistance of the optical module according to Example 2 was evaluated, the connection loss did not change even when the heating was continued at a high temperature of 100 ° C. to 300 ° C., similarly to the optical module 100 according to Example 1. Therefore, also in Example 2, similarly to Example 1, it was possible to realize an optical connection having high power resistance and heat resistance.

  As described above, in Example 2, the curing time can be reduced to 1/12 compared to Example 1 in which polysilazane is cured by standing at room temperature for 12 hours, so that the optical connection has high power resistance and heat resistance. It is possible to improve the mass production throughput while realizing the above.

Example 3
FIG. 9 shows an optical module according to Embodiment 3 of the present invention. FIG. 9 shows an optical fiber 201, a PLC 202 optically connected to the optical fiber 201, a microcapillary 203 into which the optical fiber 201 is inserted and fixed, and a portion where light does not pass between the connection end faces of the PLC 202 and the microcapillary 203. An optical module 200 having a UV curable resin adhesive layer 204 for adhering / fixing and a glass layer 205 for adhering / fixing a portion through which light passes between the connection end surfaces of the PLC 202 and the microcapillary 203 is shown. Yes. As shown in FIG. 9, the microcapillary 203 is provided with an adhesive damming groove 206.

  The PLC 202 was produced in the same procedure as in Examples 1 and 2.

  The microcapillary 203 can be constituted by, for example, a cylindrical glass member having a diameter of 1 mm and a length of 5 mm with a hole having a diameter of 0.126 mm. Such a glass microcapillary 203 has a heat-resistant temperature exceeding 500 ° C. An optical fiber 201 coated with polyimide having a heat resistance of 300 ° C. was inserted into the microcapillary 203 and fixed using a UV curable resin adhesive having a heat resistance of 200 ° C.

  The connection procedure between the PLC 202 and the microcapillary 203 into which the optical fiber 201 is inserted and fixed is the same as that in the second embodiment.

  In the third embodiment, as in the second embodiment, it is possible to realize an improvement in mass production throughput while realizing an optical connection having high power resistance and heat resistance.

  Here, in the third embodiment, for the sake of simplification, a configuration in which one optical fiber 201 is connected to each of the input and output ends is illustrated. By using a multi-core microcapillary into which the fiber 201 can be inserted and forming a plurality of optical waveguides in the PLC 202, it is possible to have a configuration in which a plurality of optical fibers 201 are connected to their input / output ends.

  In the above embodiment, the connection between the PLC and the fiber block or the microcapillary has been described. However, the principle of the present invention can be applied to optical waveguide devices in general, such as connection between PLCs and connection between fibers. is there. Further, the material of the PLC is not limited to quartz, but may be any material such as silicon or semiconductor. Further, in the above-described embodiment, the configuration in which the adhesive damming groove is provided in the fiber block or the microcapillary is shown, but the adhesive damming groove may be provided in the PLC.

Claims (6)

One or more optical fibers;
A planar lightwave circuit optically connected to the one or more optical fibers;
A fiber block in which the one or more optical fibers are inserted and fixed;
A UV curable resin adhesive layer for bonding and fixing the fiber block and the planar lightwave circuit;
A glass layer for bonding and fixing the fiber block and the planar lightwave circuit;
An optical module comprising:
The UV curable resin adhesive layer is a portion where light input or output between the one or more optical fibers and the planar lightwave circuit does not pass between connection end surfaces of the fiber block and the planar lightwave circuit. Provided in
The optical module, wherein the glass layer is provided in a portion where light input or output passes between the one or more optical fibers and the planar lightwave circuit between the connection end faces.   The optical module according to claim 1, wherein the UV curable resin adhesive layer has a heat resistant temperature of 200 ° C. or higher.   The fiber block or the planar lightwave circuit is provided with an adhesive damming groove for preventing the UV curable resin adhesive constituting the UV curable resin adhesive layer from entering the portion through which the light passes. The optical module according to claim 1, wherein the optical module is provided. A method for producing an optical module in which one or a plurality of optical fibers inserted and fixed in a fiber block and a planar lightwave circuit are optically connected,
Adjusting a connection position between the optical fiber inserted and fixed in the fiber block and the planar lightwave circuit using a fine alignment device;
A UV curable resin adhesive is applied to a portion where light input or output between the one or more optical fibers and the planar lightwave circuit does not propagate between the connection end faces of the fiber block and the planar lightwave circuit. Steps,
Irradiating the UV curable resin adhesive with UV light to bond and fix the fiber block and the planar lightwave circuit;
Between the connection end faces, a glass precursor material is filled in a portion where light input or output propagates between the one or more optical fibers and the planar lightwave circuit, and the glass precursor is formed by a liquid phase synthesis method. Curing the material; and
A method comprising the steps of:   The method of claim 4, wherein the step of curing the glass precursor material comprises curing the glass precursor material by allowing the glass precursor material to stand at room temperature. The UV curable resin adhesive has a heat resistant temperature of 200 ° C. or higher,
The method of claim 4, wherein the step of curing the glass precursor material comprises curing the glass precursor material by heating the glass precursor material.

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