JP2006058327A - Optical waveguide device and optical coupling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical waveguide device which compactly changes the direction of a light path, and to provide an optical coupling device which aligns the optical waveguide device with other optical components (a light emitting element, a light receiving element, an optical fiber, or an optical waveguide, or the like) and fixedly positions them on a base body to optically couple them to each other. <P>SOLUTION: Both end faces 4 and 5 of the optical waveguide 1 consisting of a conjugate body of a clad 2 and a core 3 are formed into reflecting surfaces slanted at 45 degrees. The optical coupling between the optical waveguide 1 and the optical fiber 8 is formed by locating the optical fiber 8 aligned with a V-groove 14 of a support base 12 to be opposed to one end face 4, and fixedly bonding the end face to an optical waveguide main surface 6. A plane type light receiving/emitting element 46 is arranged opposing the other end face 5. Positional alignment between the optical waveguide 1 and the light receiving/emitting element 46 is performed by concavo-convex engagement between an engaging convex part 11 prepared on a lower part clad of the optical waveguide 1 and an engaging concave part 42 prepared on a mounting substrate 41, and the mounting substrate 41 and the support base 12 are provided with a guide pin 13 and a guide hole 43 for assisting the positional alignment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical waveguide device that is useful in an optical wiring system and that changes the direction of light, and the optical waveguide device and other optical components (such as a light emitting element, a light receiving element, an optical fiber, or an optical waveguide). The present invention relates to an optical coupling device that is aligned and fixed to a substrate and optically coupled.

  Until now, information transmission between relatively short distances, such as between boards in an electronic device or between chips in a board, has been performed mainly by electrical signals, but in order to further improve the performance of integrated circuits, It is necessary to increase the signal speed and the signal wiring density. However, in the electric signal wiring, it is difficult to increase the speed of the electric signal and increase the density of the electric signal wiring due to problems such as signal delay due to the time constant of the wiring and generation of noise.

  Optical wiring (optical interconnection) that solves these problems is drawing attention. Optical wiring can be applied to various locations such as between electronic devices, between boards in electronic devices, or between chips in a board. For example, chips are mounted for short-distance signal transmission between chips. An optical waveguide can be formed on a substrate, and an optical transmission / communication system can be constructed using the optical waveguide as a transmission path for signal-modulated laser light or the like. In addition, optical transmission using an optical fiber as a transmission line is suitable for optical transmission over a relatively long distance such as between boards because of a small propagation loss of light.

  Therefore, for optical transmission between boards, an optical waveguide device in which the optical waveguide is optically coupled with an optical fiber is required. In such a case, in the conventional apparatus, as shown in FIG. 15A, the optical waveguide 111 and the optical fiber 113 formed on the substrate 110 are linearly opposed to each other on the end surface, and the mounting substrate 110 is arranged. Both optical axes are made to coincide with each other in the parallel direction to form an optical coupling. However, if this is done, the optical waveguide 111 and the optical fiber 113 are routed on the substrate, and other components cannot be mounted in this region, so that the mounting density is reduced and the optical wiring system is enlarged. In order to solve such a problem, an apparatus for easily changing the direction of the optical path of the optical waveguide 111 or the optical fiber 113 in a direction perpendicular to the substrate surface is required.

  As in the above example, in order to freely realize an optical wiring system with excellent packaging density, the optical path, that is, the optical waveguide device that changes the direction of the optical path in a compact manner, or the optical waveguide device and other light An optical coupling device in which components (light emitting element, light receiving element, optical fiber, optical waveguide, or the like) are aligned and fixed to a support and an optical path is connected is indispensable. At this time, it is necessary to maintain a good relative positional accuracy so that the connection loss of light input / output between the optical waveguide device and other optical components falls within an allowable range. Hereinafter, in the present specification, when the light emitting element and the light receiving element are not distinguished, they may be referred to as optical elements.

  Conventionally, as an optical coupling device for changing the direction of an optical path, for example, Patent Document 1 described below discloses an optomechanical connector using an optical fiber.

  FIG. 16 is a perspective view of the optomechanical connector 120 disclosed in Patent Document 1. As shown in FIG.

  The optomechanical connector 120 is provided with a fixture 123 at one end, and the fixture 123 is formed with a groove having a V-shaped cross section. The optical fiber 121 is inserted into the V-shaped groove, and the peripheral wall is aligned by contacting the inclined surface of the V-shaped groove. In this state, the optical fiber 121 is pressed and fixed by the lid 124. On the left and right sides of the V-shaped groove of the fixture 123, grooves having inverted trapezoidal cross sections are formed. Two guide pins 122 are inserted into the groove, and, like the optical fiber 121, are aligned by contact with the inclined side surface of the groove, and are pressed and fixed by the lid 124.

  These aggregates are held by the plastic capsule 125, and the optical fiber 121 is held in the plastic capsule 125 after being changed in direction by a desired angle, for example, 90 degrees. The optical fiber 121 is positioned and fixed by the fixture 127 and the lid 128 together with the two guide pins 126 at the other end as well as the above-described end.

  When this optomechanical connector 120 is used, for example, a guide hole for fitting with the guide pin 122 or 126 is provided in the mounting substrate on which the optical element is fixed, and the guide pin 122 is inserted into this guide hole, and this fitting is performed. Thus, the position of the optomechanical connector 120 is fixed to the mounting substrate, and optical coupling between the optical element and the optical fiber 121 is formed. Then, the path of the light emitted from the optical element and the light incident on the optical element is changed by a desired angle while propagating through the optical fiber 121.

JP 2000-509839 A (page 10-13, FIGS. 1-4 and 8)

  However, if the device that changes the direction of the optical path by routing the optical fiber as described above is too small to reduce the size of the optical fiber, the loss of propagating light increases. When the radius of curvature of the optical fiber is increased in order to suppress the loss of light, the size of the optical fiber required for the direction change increases, and the mounting density decreases. This makes it difficult to reduce the size.

  For this reason, when an optical path direction changing device using an optical fiber is mounted on a substrate, as shown in FIG. 15 (b), not only other components cannot be mounted on the substrate surface in the vicinity of the direction changing device, but also a large optical path direction. The conversion device protrudes from the substrate, and another mounting substrate cannot be juxtaposed in this space, resulting in a new cause of a decrease in mounting density.

  As described above, in order to freely realize an optical wiring system with excellent packaging density, an optical waveguide device that changes the direction of light in a compact manner is necessary, but such a device has not yet been reported. .

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an optical waveguide device that changes the direction of light in a compact manner, and the optical waveguide device and other optical components (light emitting elements, It is an object of the present invention to provide an optical coupling device in which a light receiving element, an optical fiber, an optical waveguide, etc.) are aligned and fixed to a substrate and optically coupled.

  That is, according to the present invention, the end face of the optical waveguide is formed at the reflecting surface inclined at one end of the first optical waveguide, and the optical fiber or the second optical waveguide is disposed at a position facing the inclined reflecting surface. The direction of light is redirected through reflection by the inclined reflecting surface, and the first optical waveguide and the optical fiber or the second optical waveguide are optically coupled with each other in the direction. The optical waveguide device is integrated directly or indirectly at an angle of conversion, and includes the optical waveguide device and a base on which the other optical components are mounted. The first optical waveguide is fixed to the base in a state where the other end face of the optical waveguide is optically coupled to the other optical component.

  According to the optical waveguide device of the present invention, the end face of the optical waveguide is formed on the inclined reflecting surface at one end of the first optical waveguide, and light is reflected through the reflection by the inclined reflecting surface. To the inside or outside of the optical waveguide. The optical fiber or the second optical waveguide is disposed at a position facing the inclined reflecting surface at an angle of direction change by reflection with respect to the first optical waveguide, and the first optical waveguide is disposed in the first optical waveguide. The optical waveguide is integrated directly or indirectly. For this reason, the state in which the first optical waveguide and the optical fiber or the second optical waveguide are optically coupled is reliably maintained, and the light path is directed by the reflection by the inclined reflecting surface. Since it is converted, the length required for the direction change is only about the thickness of the first optical waveguide. Therefore, it is possible to change the direction of the optical path extremely compactly as compared with the conventional optical path direction changing device that changes the direction by bending the light guide path such as an optical fiber.

  According to the optical coupling device of the present invention, the first optical waveguide of the optical waveguide device and the other optical component mounted on the base are the other end surface of the first optical waveguide. In this case, the light emitted from the other optical component or the light incident on the other optical component is redirected and emitted or incident from the optical fiber or the second optical waveguide. An extremely small optical coupling device can be realized.

  In the optical waveguide device of the present invention, the optical fiber or the second optical fiber aligned with the first optical waveguide on the light incident or emission-side main surface of the first optical waveguide at the one end. These optical waveguides are preferably bonded and fixed.

  Alternatively, the optical fiber in a state where the first optical waveguide is fixed in contact with one surface of the common support and is aligned with the first optical waveguide on the other surface of the support. It is preferable that the position of the second optical waveguide is fixed.

  Alternatively, the first optical waveguide is fixed in contact with the first support, the optical fiber or the second optical waveguide is fixed in contact with the second support, and the first optical waveguide is fixed. It is preferable that the first support and the second support are fixed to each other by abutment or concave-convex fitting in the state of being aligned with each other.

  At this time, the second support may be configured to be detachable from the first support by a known method. In this way, the so-called connector-shaped optical coupling device capable of separating and coupling the first optical waveguide and the portion of the optical fiber or the second optical waveguide as necessary. Can be realized. According to this apparatus, the first optical waveguide optically coupled to the other optical element is fixed, and the optical fiber or the second optical waveguide optically coupled to the first optical waveguide is attached and detached. Therefore, the optical wiring can be easily rearranged.

  The first and second optical waveguides may be formed of a joined body of a core and a clad, and the core may be a light guide. At this time, at least a part of the joined body is preferably made of a polymer material. By using an organic polymer material as the material of the optical waveguide, the manufacturing process of the optical waveguide can be simplified. For example, when a UV (ultraviolet) curable organic material is used, film formation by spin coating or the like and core processing by photolithography are possible, and an optical waveguide can be manufactured with inexpensive manufacturing equipment and low manufacturing cost.

  Further, the other end face of the first optical waveguide is formed as an inclined reflecting surface, and light is guided to the outside or the inside of the first optical waveguide through reflection by the inclined reflecting surface, The optical coupling with the optical component is preferably performed. In this case, as described later, there is an advantage that a surface light emitting element or a surface light receiving element can be used.

  As one form of the optical coupling device of the present invention, another main surface of the first optical waveguide is in surface contact with the base on the opposite side of the optical fiber or the second optical waveguide, and the other main surface It is preferable that the convex portion or the concave portion formed on the side and the concave portion or the convex portion formed on the base side are fitted to each other. In this case, the first optical waveguide is correctly positioned and fixed at a predetermined position of the base by self-alignment by the concave-convex fitting, and is accurately aligned with the other optical component via the base. . For this reason, compared with the alignment using a marker etc., a labor is reduced significantly, productivity improves, and the cost reduction of an optical coupling device is implement | achieved.

  In this case, it is preferable that the convex portion is formed on the clad material on the other main surface side of the first optical waveguide. In this way, the thin first optical waveguide can be fixed to the base body by the concave-convex fitting. When the thickness of the first optical waveguide is reduced, the variation in the core position in the thickness direction due to the variation in the thickness of the clad is reduced, and it becomes easy to form accurate optical coupling.

  Moreover, it is preferable that the convex part used for the said uneven | corrugated fitting and the recessed part have a reverse surface mutually, and the said convex part and a recessed part have an inclined surface with the substantially same inclination angle. Thereby, the inclined surfaces of the convex portion and the concave portion are maintained in a good contact state over a wide area, and sufficient uneven fitting is achieved by a smooth sliding motion on the contact surface.

  Further, it is preferable that a guide mechanism for guiding at least one of the optical waveguide device and the base when the first optical waveguide is fixed at least in position relative to the base. In this case, it is preferable that the guide mechanism is constituted by guide pins or guide holes provided on the optical waveguide device side and the base body side, respectively, and a fitting mechanism of these guide pins and guide holes. By such preliminary alignment by the guide mechanism, the contact of the inclined surface of the convex portion and the concave portion used for the concave-convex fitting is surely realized, and the necessary condition for alignment by the concave-convex fitting is satisfied. It is.

  As another mode of the optical coupling device of the present invention, the first optical waveguide and the base body are the opposite side of the common support body or the first support body according to claim 3 or 4. The first optical waveguide main surface is in surface contact, and the common support body or the first support body and the base are brought into contact with each other, whereby the optical waveguide device and the other optical component are brought into contact with each other. It is aligned, and the contact surface of the support or the first support with respect to the base is formed at a position away from the other end surface of the first optical waveguide by a predetermined distance. Good. Also by contact (butting), the first optical waveguide is correctly positioned and fixed at a predetermined position of the base by self-alignment, and is accurately aligned with the other optical component through the base. For this reason, compared with the alignment using a marker etc., a labor is reduced significantly, productivity improves, and the cost reduction of an optical coupling device is implement | achieved.

  In any form of the optical coupling device of the present invention, it is preferable that a concave portion is formed in the base, and the light emitting or light receiving element which is the other optical component is fixed at a predetermined position in the concave portion. At this time, the other end face of the first optical waveguide is formed as an inclined reflecting surface, and light is guided to the inside or the outside of the first optical waveguide through reflection by the inclined reflecting surface. It is preferable that optical coupling with the other optical components is performed. Thus, there is an advantage that a surface light emitting element or a surface light receiving element can be used. For example, VCSELs (Vertical Cavity Surface-Emitting Lasers) and surface-emitting LEDs are easy to manufacture, inexpensive, abundant on the market, and have excellent high-frequency characteristics and modulation. Easy to implement. In addition, light receiving elements such as photodiodes are mainly surface light receiving elements, and are easy to mount.

  The optical waveguide device may be configured to be detachable from the base. In this way, it is possible to realize a so-called connector-shaped optical coupling device capable of separating and coupling the portion of the optical waveguide device and the portion held by the base as necessary. .

  The other optical component may be a light emitting element, a light receiving element, an optical fiber, or a planar optical waveguide.

  Next, a preferred embodiment of the present invention will be described specifically and in detail with reference to the drawings.

Embodiment 1
In the first embodiment, the first optical waveguide according to claim 10 is used by using the optical waveguide device according to claim 2 in which the first optical waveguide and the optical fiber are bonded and fixed. It is an example which comprises the optical coupling device with which the said base | substrate and the said base | substrate are aligned by uneven | corrugated fitting.

  1A is a top view of the optical coupling device according to the present embodiment, and FIG. 1B is a cross-sectional view of the optical coupling device at the position of line 1A-1A in FIG. . 2A is a top view of the optical waveguide device according to the present embodiment, and FIG. 2B is a cross-sectional view of the optical waveguide device at the position of line 2A-2A in FIG. It is. FIG. 3 is a cross-sectional view of the optical coupling device at the position of line 1B-1B in FIG. 1A, showing a mechanism for realizing optical coupling by concave-convex fitting.

  As shown in FIG. 2, the optical waveguide 1 that is the first optical waveguide is composed of a joined body of a clad 2 and a core 3, and the core 3 that is a light guide is sandwiched between the lower clad and the upper clad. ing. FIG. 2A shows an example in which four cores 3 are juxtaposed, but this is only an example, and the number of cores 3 may be single or plural.

  Each layer of the clad 2 and the core 3 of the optical waveguide 1 is formed by sequentially laminating known polymer materials having different refractive indexes and patterning the core material. The refractive index of the core 3 is larger than the refractive index of the clad 2, and the relative refractive index difference Δn is, for example, 0.8%. The cross section of the core 3 is, for example, a square of 40 μm × 40 μm, and the entire thickness of the optical waveguide 1 is, for example, about 100 μm.

  The end face 4 that is the end face of the one end portion of the optical waveguide 1 and the end face 5 that is the other end face are both formed as reflective surfaces inclined at 45 degrees. At one end of the optical waveguide 1, an optical fiber 8 is bonded and fixed to the optical waveguide main surface 6, which is the main surface on the light incident or emission side of the optical waveguide 1, with an adhesive (not shown). . The diameter of the optical fiber 8 is, for example, about 125 μm.

  As shown in FIG. 3, the optical waveguide device 10 is fixed on the mounting substrate 41 while being mounted on the support 12. On one main surface of the support 12, a V-shaped groove 14 that fits with the optical fiber 8 is formed with high accuracy. The optical fiber 8 is concavo-convexly fitted with the V-shaped groove 14, and the peripheral wall is in contact with the inclined surface of the V-shaped groove 14, whereby the position of the core 9 is accurately aligned. The aligned optical fiber 8 is bonded and fixed to the support 12 with an adhesive 15 or is fixed by pressing means such as an upper lid or a leaf spring (not shown). Further, the optical fiber 8 is bonded and fixed perpendicularly to the optical waveguide main surface 6 at its end face, and is integrated with the optical waveguide 1.

  The support 12 is formed by etching or the like from a silicon substrate or the like. In particular, the V-shaped groove 14 is preferably formed by anisotropic etching of a silicon substrate described later.

  As shown in FIG. 2B, in the optical waveguide device 10 formed in this way, the optical path in the core 3 of the optical waveguide 1 is 90 degrees through reflection by the 45-degree inclined reflecting surface of one end face 4. The optical waveguide 8 is optically coupled to the optical waveguide 1 and is optically coupled to the optical path of the core 9 of the optical fiber 8 that has been directionally changed and is bonded and fixed perpendicularly to the optical waveguide main surface 6. It is integrated in the state.

  In addition to the means for forming the optical path described above, the optical waveguide 1 and the support 12 are provided with fitting convex portions 11 and guide pins 13 as alignment means for forming the optical coupling device, respectively. ing.

  The fitting convex portion 11 provided in the lower clad of the optical waveguide 1 is for precisely fitting the concave and convex portions 42 provided in the mounting substrate 41 and is formed with high accuracy by a method described later. Yes. The cross-sectional shape of the fitting convex portion 11 is a trapezoid. Further, the guide pin 13 below the support 12 is for engaging with a guide hole 43 provided in the mounting substrate 41 so that the optical waveguide 1 and the mounting substrate 41 are positioned roughly. The inclined wall surface of the fitting convex portion 11 and the inclined wall surface of the fitting concave portion 42 are reliably in contact with each other.

  On the other hand, as shown in FIG. 1, the base-side portion of the optical coupling device includes a mounting substrate 41 as the base and an optical element array 46 as the other optical component.

  The mounting substrate 41 is formed by etching or the like from a semiconductor substrate or the like. For example, if a low resistance silicon substrate of 0.05 Ωcm or less is used, the entire substrate can be used as an electrical ground (ground electrode), noise to the signal line can be reduced, and high-frequency operation of the optical element 46 is possible. It becomes. When anisotropic etching described later is used, for example, a single crystal silicon wafer having a crystal orientation (100) is used as the material of the mounting substrate 41.

  The mounting substrate 41 is provided with two means for fitting unevenness. The fitting recess 42 is used for precisely fitting with the fitting protrusion 11 provided in the lower clad of the optical waveguide 1 and is formed with high accuracy by a method described later. The cross-sectional shape of the fitting recess 42 is an inverted trapezoid. The guide hole 43 is for fitting with the guide pin 13 of the support 12.

  In addition, the mounting substrate 41 is provided with a recess 44 for mounting an optical element. The fitting recess 42 and the optical element mounting recess 44 can be formed with high relative positional accuracy by forming them simultaneously by anisotropic etching described later.

  An electrode pad 45 for electrical connection with the optical element array 46 is formed in the optical element mounting recess 44, and a marker (not shown) is formed on the optical element array 46 on the mounting substrate 41. ) And is mounted with a high accuracy of about ± 2 μm with respect to the fitting recess 42.

  The electrode pad 45 has, for example, a three-layer structure of titanium Ti / platinum Pt / gold Au from below and has a thickness of slightly less than 0.6 to 1 μm. In this configuration, the gold layer is used as a conductive material, the titanium layer is used to improve adhesion to the substrate, and the platinum layer is used as a diffusion stop layer during annealing. The optical element array 46 is, for example, a four-channel light emitting element array or light receiving element array, and a VCSEL or a light emitting diode is used as the light emitting element, and a photodiode or the like is used as the light receiving element.

  As described above, the other end surface 5 of the optical waveguide 1 is formed as a reflective surface inclined at 45 degrees with respect to the main surface of the optical waveguide 1, and light is reflected through reflection by the inclined reflective surface 5. Is guided to the inside or the outside of the optical waveguide 1 to form optical coupling with the optical element 46 arranged opposite to the optical waveguide 46. At this time, if the optical element array 46 is a light emitting element, light incident on the inclined reflecting surface 5 from the light emitting portion 47 of the light emitting element is reflected by the inclined reflecting surface 5 and guided into the core 3. After this light propagates through the core 3, it is reflected by one end face 4, which is an inclined reflecting surface, is redirected, and is guided into the core 9 of the optical fiber 8. When the optical element 46 is a light receiving element, the light propagating through the core 9 of the optical fiber 8 is reflected by the inclined reflecting surface 4 and redirected, and guided to the inside of the core 3. This light propagates through the core 3, is reflected by the inclined reflecting surface 5, and is guided to the light receiving portion 47 of the light receiving element.

  Thus, in the optical coupling device of this embodiment, the direction of the optical path can be changed extremely compactly, so that the optical coupling device is routed on the substrate, unlike the conventional example shown in FIGS. 15 (a) and 15 (b). The mounting density is not lowered by the optical fiber, and the optical wiring system is not unnecessarily enlarged. Further, when the reflection by the inclined reflection surface is also used on the other end face 5, there is an advantage that a surface light emitting element or light receiving element such as a VCSEL having a light emitting part or a light receiving part on the upper surface can be used.

  FIG. 3 shows the alignment of the optical waveguide 1 and the mounting substrate 41 by concavo-convex fitting between the fitting convex portion 11 formed on the optical waveguide 1 and the fitting concave portion 42 formed on the mounting substrate 41. 46 is a cross-sectional view illustrating a mechanism for realizing accurate optical coupling between the light emitting or receiving unit 47 of 46 and the optical waveguide core 3. FIG. FIG. 3A is a cross-sectional view showing a state of the optical coupling device before the concave-convex fitting, and FIG. 3B is a cross-sectional view showing a state where optical coupling is formed by the concave-convex fitting. These cross-sectional views are cross-sectional views at the position indicated by the line 1B-1B in FIG.

  First, as indicated by the solid line arrow in FIG. 3A, the guide pin 13 formed on the support 12 is inserted into the guide hole 43 formed on the mounting substrate 41, and the optical waveguide 1 is formed by applying light force from above. Press against the mounting substrate 41 side. At this time, the relative positions of the optical waveguide 1 and the mounting substrate 41 are aligned with an accuracy of about ± 100 μm by fitting the guide pins 13 and the guide holes 43. Preliminary alignment by fitting the guide pin 13 and the guide hole 43 causes the inclined wall surface of the fitting convex portion 11 of the optical waveguide 1 and the mounting substrate 41, as indicated by the dotted arrow in FIG. Contact with the inclined wall surface of the recess 42 for fitting is reliably realized.

  When the optical waveguide 1 is further pushed into the mounting substrate 41 in the above-described state, the inclined wall surface of the fitting convex portion 11 and the inclined wall surface of the fitting concave portion 42 slide sideways while being in contact with each other, and the fitting convex portion 11. Is guided toward the center of the recess 42 for fitting. As shown in FIG. 3B, this movement continues until the center of the fitting convex portion 11 coincides with the center of the fitting concave portion 42 to complete the fitting. Finally, the optical waveguide 1 and the mounting substrate 41 are aligned with high accuracy of about ± 5 μm by the fitting of the fitting convex portion 11 and the fitting concave portion 42.

  In the above concave-convex fitting, it is preferable that the convex portion and the concave portion have opposite surfaces and have inclined surfaces having the same inclination angle, such as the fitting convex portion 11 and the fitting concave portion 42. In this case, good contact is maintained over a wide area of the convex portion and the concave portion, and sufficient concave-convex fitting is achieved by a smooth sliding motion on the contact surface. The fitting convex part 11 and the fitting concave part 42 having the inclined surfaces having the same inclination angle and opposite to each other are formed by, for example, forming a concave part by anisotropic etching of the (100) surface of a single crystal silicon substrate described later, It can be obtained by forming a convex portion by transferring the concave portion.

  The optical coupling device shown in FIG. 1 is a detachable so-called connector-shaped optical coupling that can separate and couple the optical waveguide device side portion and the mounting substrate side portion as necessary. It can be a device. In such a case, a known pressing means such as a spring or a leaf spring is provided between the outer lid (not shown) or a known engagement such as a key-shaped claw is provided on the outer edge (not shown). Therefore, it is preferable to have a structure that can hold the entire optical coupling device as a unit.

  Next, the manufacturing method of the main members of the optical coupling device based on this Embodiment is demonstrated using FIGS.

  FIG. 4 is a flowchart showing a process of manufacturing the main part of the mounting substrate 41. In addition, this figure is sectional drawing in the position of the 1B-1B line | wire of Fig.1 (a).

  First, as shown in FIG. 4A, a single crystal silicon wafer 51 having a crystal orientation (100) is prepared as a substrate, and a thermal oxide film 52 is formed on the surface.

  Next, as shown in FIG. 4B, a photoresist layer 53 is formed by patterning so as to mask portions other than the portions where the fitting recesses 42 and the optical element mounting recesses 44 are formed, and then fluorine. The thermal oxide film 52 in the opening is removed by reactive ion etching (RIE) using a system gas. After completion, the photoresist layer 53 used as a mask is removed by ashing with oxygen plasma.

  Next, as shown in FIG. 4C, the silicon substrate 51 is immersed in a potassium hydroxide aqueous solution or TMAH (Tetra Methyl Ammonium Hydroxide) aqueous solution having a temperature of 70 ° C. and a concentration of 20% by mass, and the silicon oxide film is used as a mask. The recesses for fitting 42 and the recesses for mounting optical elements 44 are formed by anisotropic etching of silicon. The depth of the concave portion is set to be slightly larger than the height of the optical element to be mounted. For example, if the height of the optical element is 100 to 200 μm, the depth of the recess is also set to about 100 to 200 μm.

  When a single crystal silicon wafer 51 having a crystal orientation (100) is used as the substrate, the inclination angle of the inclined surface of the recess formed by the anisotropic etching is constant at 54.7 degrees regardless of the etching conditions. .

  Next, as shown in FIG. 4D, an electrode pad 45 is formed in the optical element mounting recess 44. In this embodiment, the structure of the electrode is a three-layer structure of titanium Ti / platinum Pt / gold Au from the bottom, with a thickness of slightly less than 0.6 to 1 μm, and vapor deposition is used to form the metal film. Thereafter, annealing treatment may be performed at 300 to 400 ° C. in order to reduce the contact resistance with the silicon substrate 51. In the above configuration, the gold layer is used as a conductive material, the titanium layer is used to enhance the adhesion to the substrate, and the platinum layer is used as a diffusion stop layer during annealing. The electrode pad 45 forms an electrode pattern by a lift-off process using a photoresist. The method for forming the metal film is not limited to this, and for example, a plating method or a sputtering method may be used. As a pattern forming method, a method of forming a pattern by etching after forming a metal layer on the entire surface may be employed.

  Next, as shown in FIG. 4E, the optical element array 46 is mounted in the optical element mounting recess 44 with a marker (not shown) formed on the mounting substrate 41 as a mark.

  In the above process, since the fitting recess 42 and the optical element mounting recess 44 are formed by the same etching process, the optical element array 46 has a high relative positional accuracy. It is mounted with high accuracy of about ± 2 μm.

  The method for forming the concave / convex fitting V-shaped groove 14 with the optical fiber 8 on the support 12 is substantially the same as the method for forming the fitting concave portion 42 on the mounting substrate 41. That is, a single crystal silicon wafer having a crystal orientation (100) is prepared as a base material, a thermal oxide film is formed on the surface, and a photoresist layer is patterned so as to mask a portion other than a portion where the V-shaped groove 14 is formed. Form. Thereafter, the thermal oxide film in the opening is removed by RIE using a fluorine-based gas, and the photoresist layer used as a mask is removed by ashing, and then anisotropic etching of silicon with a potassium hydroxide aqueous solution or the like is performed. A V-shaped groove 14 is formed. Other portions of the support 12 are also formed mainly by etching or dicing.

  FIG. 5 and FIG. 6 are flowcharts showing a process of manufacturing a main part of the optical waveguide 1. In addition, this figure is sectional drawing in the position of the 1B-1B line | wire of FIG.

  In these steps, first, a recess is formed in the transfer substrate in the same steps as in FIGS. 4A to 4C, and then an optical waveguide material is deposited on the transfer substrate surface having the recess. Then, an optical waveguide layer is formed, and this optical waveguide layer is peeled off from the transfer substrate to obtain the optical waveguide 1 having the fitting convex portion 11 on one surface.

  First, as shown in FIG. 5A, as in FIG. 4A, a single crystal silicon wafer 61 having a crystal orientation (100) is prepared as a substrate, and a thermal oxide film 62 is formed on the surface.

  Next, as shown in FIG. 5B, after the photoresist layer 63 is formed by patterning so as to mask a portion other than the portion where the concave portion 64 corresponding to the convex portion 11 for fitting of the optical waveguide 1 is formed. Then, the thermal oxide film 62 at the opening is removed by RIE using a fluorine-based gas. After completion, the photoresist layer 63 used as a mask is removed by ashing with oxygen plasma.

  Next, as shown in FIG. 5C, the silicon substrate 61 is immersed in a potassium hydroxide aqueous solution or a TMAH aqueous solution having a temperature of 70 ° C. and a concentration of 20% by mass, and silicon anisotropy is used as a mask. A recess 64 is formed by etching to obtain a transfer substrate 65. When the single crystal silicon wafer 61 having the crystal orientation (100) is used as the substrate material, the inclination angle of the inclined surface of the recess formed by anisotropic etching is 54.7 degrees regardless of the etching conditions and the like. This coincides with the inclination angle of the inclined surface of the fitting recess 42 formed on the substrate 41.

  The size of the recess 64 is determined in consideration of the expansion and contraction of the optical waveguide layer that occurs at the time of peeling. Since the size of the expansion and contraction is fixed depending on the material of the optical waveguide layer, the optical waveguide layer is formed so that the size of the fitting convex portion 11 formed by the transfer of the concave portion 64 after peeling is the same as that of the fitting concave portion 42. The size of the recess 64 is determined in advance according to the material. In general, thermosetting resins tend to be greatly deformed, and ultraviolet curable resins tend to be less deformed.

  Next, as shown in FIG. 5D, a polymer organic material is first applied to the transfer substrate 65 by spin coating, and cured by ultraviolet irradiation or heating to form the lower cladding 2a.

  Next, as shown in FIG. 6E, a polymer organic material having a refractive index higher than that of the lower clad 2a is applied on the lower clad 2a and cured by ultraviolet irradiation or heating to form the core 3. . When forming the core 3, the ultraviolet irradiation region is limited by a mask, or after forming a core material on the entire surface, a pattern is formed with a photoresist, and an unnecessary portion of the core is removed by RIE. A core 3 having a circuit pattern is formed.

  Next, as shown in FIG. 6 (f), the same organic polymer material as that of the lower clad 2a is applied on the lower clad 2a and the core 3, and cured by ultraviolet irradiation or heat to form the upper clad 2b. .

  Next, as shown in FIG. 6G, a part of the upper clad 2b, the core 3, the lower clad 2a, and the transfer substrate 65 is cut with a V-shaped diamond blade or the like, and the end face 5 which is the other end face. Are formed on a 45-degree inclined reflecting surface. The position at which the 45-degree inclined reflecting surface 5 is formed is determined based on a marker (not shown) formed in advance on the silicon substrate, so that the concave portion 64 of the transfer substrate 65 and the fitting convex portion 11 of the optical waveguide 1 are formed. On the other hand, it can be positioned with high accuracy.

  Next, as shown in FIG. 6 (h), the optical waveguide portion above the lower clad 2 a is peeled from the transfer substrate 65 to obtain the optical waveguide sheet 66 having the fitting convex portion 11.

  Next, as shown in FIG. 6 (i), the optical waveguide sheet 66 is fixed upside down on the temporary substrate 67, and the end surface 4 which is the one end surface is also formed on a reflective surface inclined at 45 degrees, The formation of the optical waveguide 1 is finished.

  According to the manufacturing method of the present embodiment, a single crystal silicon substrate having a crystal orientation (100) is used as a material for forming the mounting substrate 41 and the transfer substrate 65, and the fitting recess 42 of the mounting substrate 41 is anisotropically etched. Since the concave portion 64 of the transfer substrate 65 is formed, the inclination angle of the inclined surface of the concave portion to be formed is constant at 54.7 degrees regardless of the etching conditions. For this reason, the fitting convex portion 11 of the optical waveguide 1 formed using the transfer substrate 65 is opposite to the fitting concave portion 42 formed on the mounting substrate 41, and is excellent over a wide range of inclined surfaces. Contact is maintained, and a sufficient slip fit on the contact surface achieves a sufficient uneven fit.

  Further, the inclination angle of the inclined surface of the concave portion of 54.7 degrees is convenient not only for causing uneven fitting due to a smooth sliding motion on the contact surface, but also for peeling the optical waveguide 1 from the transfer substrate 65. Is an angle.

  The method for forming the protrusions and recesses for fitting is not limited to the method by anisotropic etching of a single crystal silicon substrate. For example, a similar structure can be obtained by processing the substrate by high-precision diving or the like. Sometimes it forms. In this case, the substrate is not limited to a single crystal silicon substrate, and for example, a plastic substrate, a glass substrate, or a ceramic substrate can be used.

  As described above, in the optical waveguide device according to the present embodiment, one end face 4 of the optical waveguide 1 is formed on the reflecting surface inclined at 45 degrees, and the optical waveguide 1 is reflected through the reflection by the inclined reflecting surface. Is optically coupled to the optical fiber 8. Since this optical waveguide device changes the direction of the optical path by reflection, the optical path system can easily and compactly change the path of light in the desired direction, has a high mounting density, and allows flexible wiring. Can contribute effectively to the construction of

  The optical coupling device according to the present embodiment includes the above-described optical waveguide device as a component, and both end surfaces 4 and 5 of the optical waveguide 1 fixed on the mounting substrate are formed on reflective surfaces inclined at 45 degrees. It has a novel and unique structure in which one end face 4 is optically coupled to the optical fiber 8 and the other end face 5 is optically coupled to the optical element 46. Therefore, it is possible to realize an extremely small optical coupling device that changes the direction of the light emitted from the optical element 46 or the light incident on the optical element 46 and emits or enters the light from the optical fiber 8. A surface light emitting element or a light receiving element can be used as 46. In addition, since the optical waveguide core has an array structure, the number of channels can be easily changed.

  Such an optical coupling device can be used in various applications because of its unique structure. For example, a large number of surface-emitting light-emitting elements or surface-receiving types mounted on a mounting substrate at high density. A compact high-density mounting optical input / output device specialized only in the function of optically coupling between the light receiving element and a plurality of optical fibers arranged in a direction orthogonal to the mounting substrate is conceivable. Such a wiring structure cannot be realized by a conventional optical coupling device.

  Further, in the optical coupling device of the present embodiment, the alignment between the optical waveguide 1 and the mounting substrate 41 can be performed efficiently and with high accuracy by the concave-convex fitting. Further, for example, even when the configuration of the optical waveguide is changed, for example, the number of channels configuring the optical waveguide is increased, the same structure can be used.

Embodiment 2
The second embodiment uses the optical waveguide device described in claim 3 in which the first optical waveguide and the optical fiber are fixed to the common support and optically coupled. It is an example which comprises the optical coupling device described in above, wherein the first optical waveguide and the base are aligned by contact.

  FIG. 7A is a top view of the optical waveguide device according to the present embodiment, and FIG. 7B is a cross-sectional view of the optical waveguide device taken along line 7A-7A in FIG. 7A. . 8A is a top view of the optical coupling device according to the present embodiment, and FIG. 8B is a cross-sectional view of the optical coupling device at the position of line 8A-8A in FIG. 8A. It is.

  As shown in FIG. 7, the optical waveguide 1 and the optical fiber 8 as the first optical waveguide are essentially the same as those described in the first embodiment.

  That is, the optical waveguide 1 is composed of a joined body of the clad 2 and the core 3, and the core 3 serving as a light guide is sandwiched between the lower clad and the upper clad. FIG. 7A shows an example in which four cores 3 are juxtaposed, but the number of cores 3 may be single or plural. The refractive index of the core 3 is larger than the refractive index of the clad 2, and the relative refractive index difference Δn is, for example, 0.8%. The cross section of the core 3 is, for example, a square of 40 μm × 40 μm, and the entire thickness of the optical waveguide 1 is, for example, about 100 μm.

  Further, the end surface 4 which is the end surface of the one end portion of the optical waveguide 1 and the end surface 5 which is the other end surface are both formed on a reflecting surface inclined at 45 degrees. The optical waveguide 1 is optically coupled to the optical fiber 8 at one end face 4. The diameter of the optical fiber 8 is, for example, about 125 μm.

  One of the differences between the second embodiment and the first embodiment is the difference in the mechanism for optically coupling and integrating the optical waveguide 1 and the optical fiber 8. In the first embodiment, the optical fiber 8 is bonded and fixed perpendicularly to the main surface 6 of the optical waveguide 1. However, in the second embodiment, the optical fiber 8 is in contact with two orthogonal surfaces of the support 21 that is the common support. The optical waveguide 1 and the optical fiber 8 are fixed in position to form an optical coupling, and both are integrated.

  The support 21 is a substrate made of, for example, silicon. The material of the support 21 may be a glass substrate or a ceramic substrate other than a silicon substrate, but a semiconductor substrate, particularly a silicon substrate, is preferable because it can be processed by a semiconductor processing technique. And like the support body 12 of Embodiment 1, the V-shaped groove | channel 22 which carries out uneven | corrugated fitting with the optical fiber 8 is formed in the one surface with high precision by methods, such as anisotropic etching.

  The optical fiber 8 is unevenly fitted to the V-shaped groove 22, and the peripheral wall is in contact with the inclined surface of the V-shaped groove 22, whereby the position of the core 9 is accurately aligned. The aligned optical fiber 8 is bonded and fixed to the support 21 with an adhesive (not shown) or is fixed by a pressing means such as an upper lid (not shown) or a leaf spring. On the other hand, the optical waveguide main surface 6 of the optical waveguide 1 is fixed to the other surface of the support 21 perpendicular to the surface having the V-shaped groove 22 by bonding or the like. The optical fiber 8 and the main surface 6 may or may not be bonded.

  As shown in FIG. 7B, in the optical waveguide device formed in this way, the optical path in the core 3 of the optical waveguide 1 is in the direction of 90 degrees through reflection by the 45-degree inclined reflecting surface of one end face 4. The optical waveguide 8 is converted and fixed so as to coincide with the optical path in the core 9 of the optical fiber 8 fixed to the surface orthogonal to the optical waveguide main surface 6, and the optical waveguide 1 and the optical fiber 8 are optically coupled. It is integrated in the state.

  Another important point of the second embodiment different from the first embodiment is that the optical coupling between the optical waveguide 1 and an optical element 76 described later is due to the contact (butting) between the support 21 and the mounting substrate 71. It is formed by alignment. Therefore, in addition to the means for forming the optical path, the support body 21 is provided with contact surfaces 23 and 24 that are accurately and flatly formed on two orthogonal surfaces as positioning means.

  On the other hand, as shown in FIG. 8, in the portion on the base side of the optical coupling device, an optical waveguide support surface 72 that holds the optical waveguide 1 and a contact surface 73 with the support 21 are mounted on the mounting substrate 71 that is the base. 74, an optical element 76, a recess 75 for fixing the optical element 76, and the like.

  As in the first embodiment, the mounting substrate 71 is formed by etching or the like from a semiconductor substrate or the like. For example, if a low-resistance silicon substrate of 0.05 Ωcm or less is used, the entire substrate can be used as an electrical ground (ground electrode), noise to the signal line can be reduced, and high-frequency operation of the optical element 76 is possible. It becomes. In addition, the mounting method of the optical element 76 is the same as that of the first embodiment.

  As shown in FIG. 8B, in the state in which the optical coupling is formed, the optical waveguide 1 has the main surface 7 which is the opposite optical waveguide main surface facing the optical waveguide support surface 72 of the mounting substrate 71. Hold in contact. On the other hand, since the optical element 76 is fixed in the recess 75, the distance between the optical waveguide 1 and the optical element 76 in the height direction is controlled by adjusting the depth of the recess 75.

  As described above, the other end surface 5 of the optical waveguide 1 is formed as a reflection surface inclined at 45 degrees with respect to the main surface 6 or 7 of the optical waveguide 1, and the reflection by the inclined reflection surface 5 is performed. Thus, the light is guided to the inside or the outside of the optical waveguide 1 to form an optical coupling with the optical element 76 arranged to face. At this time, if the optical element 76 is a light emitting element, the light incident on the inclined reflecting surface 5 from the light emitting portion of the light emitting element is reflected by the inclined reflecting surface 5 and guided into the core 3. After this light propagates through the core 3, it is reflected by one end face 4, which is an inclined reflecting surface, is redirected, and is guided into the core 9 of the optical fiber 8. Further, when the optical element 76 is a light receiving element, the light propagating through the core 9 of the optical fiber 8 is reflected by the inclined reflecting surface 4 and redirected and guided into the core 3. After propagating through the core 3, the light is reflected by the inclined reflecting surface 5 and guided to the light receiving portion of the light receiving element 76.

  Thus, as in the first embodiment, the optical coupling device of the present embodiment can change the direction of the optical path very compactly, so the conventional example shown in FIGS. 15A and 15B. Unlike the optical fiber drawn on the substrate, the mounting density is not lowered, and the optical wiring system is not unnecessarily enlarged. Further, when the reflection by the inclined reflection surface is also used on the other end face 5, there is an advantage that a surface light emitting element or light receiving element such as a VCSEL having a light emitting part or a light receiving part on the upper surface can be used.

  FIGS. 9A and 9B are cross-sectional views (a) and (b) and a top view (c) showing a step of performing alignment in the left-right direction of the drawing by contact based on the second embodiment. In addition, sectional drawing (a) shows the state before contact, and sectional drawing (b) and top view (c) show the state after contact.

  As shown in FIG. 9A, the contact surface 23 of the support 21 is formed at a position away from the other end surface 5 of the optical waveguide 1 by a predetermined distance 25. The optical element 76 is fixed at a position away from the contact surface 73 of the mounting substrate 71 by a predetermined distance 77. For this reason, as shown in FIG. 9B, when the contact surface 23 and the contact surface 73 are brought into contact with each other, the other end surface 5 of the optical waveguide 1 and the optical element 76 are arranged in the left-right direction in FIG. It is aligned at a position separated by a predetermined distance.

  Further, as shown in FIG. 9C, if the contact portion between the contact surface 23 and the contact surface 73 is sufficiently widened, the correction of the angular deviation between the support 21 and the mounting substrate 71 by the contact is performed. Is also done.

  FIG. 9C shows a state where only the contact between the contact surface 23 and the contact surface 73 is performed and the contact between the contact surface 24 and the contact surface 74 is not performed. Thereafter, by making contact between the contact surface 24 and the contact surface 74, alignment in the depth direction of FIG. 9B can be performed.

  As an actual alignment step, for example, first, the support body 21 is moved in the right direction in FIG. 9, the contact surface 23 is brought into contact with the contact surface 73, and the position in the left-right direction in FIG. Next, the support body 21 is moved in the depth direction along the contact surface 73, the contact surface 24 is contacted with the contact surface 74, and alignment in the depth direction is performed.

  As described above, the alignment in the two-dimensional direction is performed only by repeating the contact twice. When combined with the alignment in the height direction by adjusting the depth of the concave portion 75 described above, complete alignment in the three-dimensional direction is performed, and optical coupling between the light guide core 3 and the light emitting or light receiving portion of the optical element 76 is formed. Is done. Further, by adding a contact surface in the vertical direction and repeating the contact three times, it is possible to perform alignment in all three-dimensional directions only by contact of the contact surface.

  The optical coupling device shown in FIG. 8 is a detachable, so-called connector-shaped optical coupling that can separate and couple the optical waveguide device side portion and the mounting substrate side portion as necessary. It can be a device. In such a case, a known pressing means such as a spring or a leaf spring is provided between the outer lid (not shown) or a known engagement such as a key-shaped claw is provided on the outer edge (not shown). Therefore, it is preferable to have a structure that can hold the entire optical coupling device as a unit.

  FIG. 10 is a flowchart showing a part of the process of manufacturing the optical waveguide device. Note that FIG. 10 is a cross-sectional view at the same position as the cross-sectional view of FIG.

  First, as shown in FIG. 10A, as in the first embodiment, each layer of the lower clad 2a, the core 3 and the upper clad 2b of the optical waveguide 1 is formed on the substrate 81 by, for example, different known refractive indexes. The polymer material is applied by spin coating or the like, cured by ultraviolet irradiation or heating, sequentially laminated, and patterned by patterning the core material.

  Next, as shown in FIG. 10 (b), a 45 ° oblique process is performed by dicing with a V-shaped blade, and one end face 4 of the optical waveguide is formed on an inclined reflective surface. Subsequently, although not shown in the figure, the optical waveguide is peeled off from the substrate 81, fixed upside down on the temporary substrate in the same manner as in the first embodiment, and dicered with a V-shaped blade. The end surface 5 is also formed on a reflective surface inclined at 45 degrees to obtain the optical waveguide 1.

  Next, as shown in FIG. 10C, the optical waveguide 1 is bonded and fixed to the base material 26 processed into the support 21. Subsequently, the base material 26 is cut at a position away from the other end surface 5 by a predetermined distance 25 to form the contact surface 23 with the mounting substrate 71, thereby obtaining the support 21. At this time, it is possible to form the contact surface 23 with an accuracy of ± several μm by cutting while detecting the edge 5a of the one end surface 5 by image observation using a CCD (Charge Coupled Device) camera and a microscope. it can. The contact surface 23 can be formed by cutting and then subjected to an etching process, whereby the dimensional accuracy can be improved or the stepped shape can be processed.

  As described above, according to the present embodiment, complete alignment in the three-dimensional direction can be easily performed by bringing the optical waveguide main surface 7 and the support 21 into contact with the mounting substrate 71. . According to this method, the alignment operation is simple because only the contact portions are brought into contact with each other. In addition, if the contact is performed over a sufficiently wide region, accurate alignment can be realized regardless of the precision of manufacturing details as long as the accuracy of the position of the entire contact portion is maintained. Therefore, the optical coupling can be easily formed with good productivity and yield, at low cost, and with high accuracy.

  Since the mechanical strength of the inclined end face of the optical waveguide is generally weak, it is difficult to align the optical waveguide by directly contacting the inclined end face portion. According to this embodiment, since positioning can be performed without applying a mechanical load to the optical waveguide, long-term reliability is excellent. Further, for example, even when the configuration of the optical waveguide is changed, for example, the number of channels configuring the optical waveguide is increased, the same structure can be used.

  As described above, the present embodiment is different from the first embodiment in that the optical coupling between the optical waveguide 1 and the optical fiber 8 and the optical coupling between the optical waveguide 1 and the optical element 76 are different from those in the first embodiment. Since the basic structure for changing the direction of the path by reflection is the same as in the first embodiment, it is needless to say that the same effect as in the first embodiment can be obtained in this respect.

  That is, in the optical waveguide device according to the present embodiment, one end face 4 of the optical waveguide 1 is formed on a reflective surface inclined at 45 degrees, and the optical waveguide 1 is connected to the optical fiber 8 through reflection by the inclined reflective surface. It is optically coupled. Since this optical waveguide device changes the direction of the optical path by reflection, the optical path system can easily and compactly change the path of light in the desired direction, has a high mounting density, and allows flexible wiring. Can contribute effectively to the construction of

  In addition, the optical coupling device according to the present embodiment includes the above-described optical waveguide device as a constituent element, and both end surfaces 4 and 5 of the optical waveguide 1 fixed on the mounting substrate are formed on reflective surfaces inclined at 45 degrees. Thus, the optical fiber 8 is optically coupled at one end face 4 and the optical element 76 is optically coupled at the other end face 5. Therefore, it is possible to realize an extremely small optical coupling device that changes the direction of the light emitted from the optical element 76 or the light incident on the optical element 76 and emits or enters the light from the optical fiber 8. A surface light emitting element or a light receiving element can be used as 76. In addition, since the optical waveguide core has an array structure, the number of channels can be easily changed.

  Such an optical coupling device can be used in various applications because of its unique structure. For example, a large number of surface-emitting light-emitting elements or surface-receiving types mounted on a mounting substrate at high density. A compact high-density mounting optical input / output device specialized only in the function of optically coupling between the light receiving element and a plurality of optical fibers arranged in a direction orthogonal to the mounting substrate is conceivable. Such a wiring structure cannot be realized by a conventional optical coupling device.

Embodiment 3
In the third embodiment, the position of the first optical waveguide is fixed in contact with the first support, and the optical fiber or the second optical waveguide is in contact with the second support. An optical waveguide device in which the first support and the second support are fixed to each other by contact or concave-convex fitting in a state where the first support and the second support are aligned with each other. In this example, the optical coupling device according to claim 15 is configured in which the first optical waveguide and the base are aligned by contact.

  In the present embodiment, the support 21 in the second embodiment is supported by the support 31 that is the first support that holds the optical waveguide 1 and the second support that holds the optical fiber 8. A so-called connector-shaped optical coupling device that can be divided into bodies 32 and that can be positioned by contact between the support 31 and the support 32 and can be separated or combined as necessary. This is only different from the second embodiment. The following description will be given with emphasis on the changes from the second embodiment.

  FIG. 11A is a top view of the optical coupling device according to the present embodiment, and FIG. 11B is a cross-sectional view of the optical coupling device at the position of line 11A-11A in FIG. . This optical coupling device is not different from the optical coupling device based on Embodiment 2 shown in FIG. 8 except that the support 21 is replaced with a support 31 and a support 32.

  FIG. 12 is an exploded sectional view showing the structure of the optical coupling device at the abutting position for easy understanding.

  As shown in FIG. 12, the mounting substrate side portion is the same as in the second embodiment, and the optical waveguide support surface 72 holding the optical waveguide 1, the contact surfaces 73 and 74, and the optical element 76 are fixed to the mounting substrate 71. A recess 75, an optical element 76, and the like are provided.

  The portion on the optical waveguide device side is divided into two, and the optical waveguide 1 is fixed to the support 31 by an adhesive or the like instead of the support 21. In addition to this, the support 31 is provided with a contact surface 23 and (not shown) 24. On the other hand, the position of the optical fiber 8 is fixed to the support 32 instead of the support 21. Similar to the support body 21, the support body 32 is provided with a V-shaped groove 22 for aligning and fixing the position of the optical fiber 8.

  The support 31 and the support 32 have three contact surfaces 33 and 34 (the other one is not shown) and contact surfaces 35 and 36 (the other one is not shown) orthogonal to each other. Is provided. The support body 31 and the support body 32 are formed so as to be accurately positioned and fixed to each other in a three-dimensional manner by contact with these three surfaces. It is made to have the same function as the support 21.

  Also, the support 31 and the support 32 are springs between the outer lid (not shown) so as to realize a so-called connector-shaped optical coupling device that can be separated or coupled as necessary. The support 31 and the support 32 can be held together by providing a known pressing means such as a plate spring or by providing a known engagement with a key-shaped claw or the like on an outer edge (not shown). .

  By adopting such a configuration, the optical coupling device according to the present embodiment is a so-called connector-shaped light that can separate and combine the optical waveguide 1 and the optical fiber 8 as necessary. It can be a coupling device. According to this apparatus, the optical wiring can be rearranged by attaching and detaching and replacing the optical fiber 8 optically coupled to the optical waveguide 1 while the optical waveguide 1 optically coupled to the optical element 76 is fixed. it can.

  This embodiment is essentially the same as the second embodiment except that the support portion holding the optical waveguide 1 and the support portion holding the optical fiber 8 can be divided. Needless to say, it has the same effect as the second embodiment.

  That is, in the optical waveguide device according to the present embodiment, one end face 4 of the optical waveguide 1 is formed on a reflective surface inclined at 45 degrees, and the optical waveguide 1 is connected to the optical fiber 8 through reflection by the inclined reflective surface. It is optically coupled. Since this optical waveguide device changes the direction of the optical path by reflection, the optical path system can easily and compactly change the path of light in the desired direction, has a high mounting density, and allows flexible wiring. Can contribute effectively to the construction of

  In addition, the optical coupling device according to the present embodiment includes the above-described optical waveguide device as a constituent element, and both end surfaces 4 and 5 of the optical waveguide 1 fixed on the mounting substrate are formed on reflective surfaces inclined at 45 degrees. Thus, the optical fiber 8 is optically coupled at one end face 4 and the optical element 76 is optically coupled at the other end face 5. Therefore, it is possible to realize an extremely small optical coupling device that changes the direction of the light emitted from the optical element 76 or the light incident on the optical element 76 and emits or enters the light from the optical fiber 8. A surface light emitting element or a light receiving element can be used as 76. In addition, since the optical waveguide core has an array structure, the number of channels can be easily changed.

  Further, the optical waveguide main surface 7 comes into surface contact with the mounting substrate 71, and the support 21 and the mounting substrate 71 come into contact with each other, whereby complete alignment in the three-dimensional direction is easily performed. According to this method, the alignment operation is simple because only the contact portions are brought into contact with each other. In addition, if the contact is performed over a sufficiently wide region, accurate alignment can be realized regardless of the precision of manufacturing details as long as the accuracy of the position of the entire contact portion is maintained. Therefore, the optical coupling can be easily formed with good productivity and yield, at low cost, and with high accuracy.

  Further, since the mechanical strength of the inclined end face of the optical waveguide is generally weak, it is difficult to align the optical waveguide by directly abutting the inclined end face portion. According to this embodiment, since positioning can be performed without applying a mechanical load to the optical waveguide, long-term reliability is excellent. Further, for example, even when the configuration of the optical waveguide is changed, for example, the number of channels configuring the optical waveguide is increased, the same structure can be used.

Embodiment 4
The fourth embodiment is an example in which an optical waveguide 38 that is the second optical waveguide is used instead of the optical fiber 8.

  13A is a top view of the optical coupling device according to the present embodiment, and FIG. 13B is a cross-sectional view of the optical coupling device at the position of line 13A-13A in FIG. 13A. . FIG. 14 is an exploded sectional view showing the structure of the optical coupling device at the abutting position for easy understanding. As can be seen from FIGS. 13 and 14, this optical coupling device is implemented in an optical waveguide 38 except that the optical waveguide 38 is used instead of the optical fiber 8 and the V-shaped groove 22 is not provided in the support 37. There is no difference from the optical coupling device based on the third aspect.

  When a film-like optical waveguide having no substrate is used as the optical waveguide 38, a flexible optical wiring can be formed more easily than the optical fiber 8. This is suitable, for example, when a jumper line connection is made between optical components in the board.

  Since the present embodiment is essentially the same as the third embodiment except for the points described above, it is needless to say that the present embodiment has the same effect as the third embodiment described above.

  As mentioned above, although this invention was demonstrated based on embodiment, it cannot be overemphasized that this invention is not limited to these examples at all, and can be suitably changed in the range which does not deviate from the main point of invention.

  For example, the optical waveguide device described in Embodiments 2 to 4 may be provided with a convex or concave portion for fitting, and the optical waveguide device may be fixed to the mounting substrate having the concave or convex portion for fitting by concave and convex fitting. it can.

  The optical coupling device of the present invention is suitably used in optical wiring applicable to various places such as between electronic devices, between boards in electronic devices or between chips in a board, and is small, low cost, and high in cost. It can contribute to the construction of high performance optical transmission / communication systems.

It is the top view (a) and sectional drawing (b) of the optical coupling device based on Embodiment 1 of this invention. The top view (a) and sectional drawing (b) of an optical waveguide device are the same. FIG. 6 is a cross-sectional view for explaining a mechanism for realizing optical coupling by concavity and convexity fitting between the fitting convex portion of the optical waveguide and the fitting convex portion of the mounting substrate. It is a flowchart which shows the process of producing the principal part of a mounting board | substrate equally. It is a flowchart which shows the process of producing the principal part of an optical waveguide same as the above. It is a flowchart which shows the process of producing the principal part of an optical waveguide same as the above. It is the top view (a) and sectional drawing (b) of the optical waveguide device based on Embodiment 3 of this invention. The top view (a) and sectional drawing (b) of an optical coupling device are the same. It is explanatory drawing which shows the process of aligning by contact | abutting similarly. It is a flowchart which shows a part of manufacturing process of an optical waveguide apparatus similarly. It is the top view (a) and sectional drawing (b) of the optical coupling device based on Embodiment 3 of this invention. It is explanatory drawing which decomposes | disassembles and shows the structure of an optical coupling device. It is the top view (a) and sectional drawing (b) of the optical coupling device based on Embodiment 4 of this invention. It is explanatory drawing which decomposes | disassembles and shows the structure of an optical coupling device. It is explanatory drawing which shows the problem of the conventional optical waveguide apparatus which optically coupled the optical waveguide with the optical fiber. FIG. 10 is a perspective view of an optomechanical connector for changing the direction of light, disclosed in Patent Document 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical waveguide, 2 ... Optical waveguide clad, 2a ... Lower clad, 2b ... Upper clad,
3 ... optical waveguide core, 4 ... one end face (reflecting face inclined at 45 degrees),
5 ... the other end face (reflecting face inclined at 45 degrees), 5a ... the edge of the other end face,
6 ... Optical waveguide main surface on the light incident or emission side (optical fiber or second optical waveguide side),
7 ... Optical waveguide main surface on the opposite side (mounting substrate side), 8 ... Optical fiber, 9 ... Optical fiber core,
DESCRIPTION OF SYMBOLS 10 ... Optical waveguide apparatus, 11 ... Convex convex part, 12 ... Support body, 13 ... Guide pin,
14 ... V-groove, 15 ... adhesive, 21 ... support, 22 ... V-groove, 23, 24 ... contact surface,
25 ... predetermined distance, 26 ... base material of support 21, 31, 32 ... support,
33-36 ... contact surface, 37 ... support, 38 ... optical waveguide, 41 ... mounting substrate,
42: recessed portion for fitting, 43 ... guide hole, 44 ... recessed portion for mounting optical element,
45 ... Electrode pads (titanium Ti / platinum Pt / gold Au), 46 ... optical element array,
47: Light emitting or light receiving portion, 48: Bonding pad, 51: Silicon substrate,
52 ... Silicon oxide film, 53 ... Photoresist layer, 61 ... Silicon substrate,
62 ... Silicon oxide film, 63 ... Photoresist layer, 64 ... Recess, 65 ... Transfer substrate,
66 ... Optical waveguide sheet, 67 ... Temporary substrate, 71 ... Mounting substrate,
72 ... Optical waveguide support surface, 73, 74 ... Abutting surface, 75 ... Recess, 76 ... Optical element,
77 ... predetermined distance, 81 ... substrate, 110 ... mounting substrate,
111 ... Optical waveguide, 112 ... Optical element, 113 ... Optical fiber,
120 ... Optomechanical connector, 121 ... Optical fiber,
122, 126 ... guide pins, 123, 127 ... fixtures, 124, 128 ... lids,
125 ... Plastic capsule

Claims (25)

  An end face of the first optical waveguide is formed on an inclined reflecting surface, and an optical fiber or a second optical waveguide is disposed at a position facing the inclined reflecting surface, and the inclined reflecting surface is provided. The direction of the light is changed through reflection by the optical fiber, and the first optical waveguide and the optical fiber or the second optical waveguide are optically coupled with each other at an angle of the direction change. An optical waveguide device integrated directly or indirectly.   At the one end, the optical fiber or the second optical waveguide aligned with the first optical waveguide is bonded and fixed to the main surface on the light incident or exit side of the first optical waveguide. The optical waveguide device according to claim 1.   The first optical waveguide is fixed in contact with one surface of a common support, and the optical fiber or the first optical fiber in a state aligned with the first optical waveguide is fixed to the other surface of the support. The optical waveguide device according to claim 1, wherein two optical waveguides are fixed in position.   The first optical waveguide is fixed in contact with the first support, the optical fiber or the second optical waveguide is fixed in contact with the second support, and the first optical waveguide and the position are fixed. The optical waveguide device according to claim 1, wherein the first support body and the second support body are fixed to each other by contact or concave-convex fitting in the combined state.   The optical waveguide device according to claim 4, wherein the second support is configured to be detachable from the first support.   2. The optical waveguide device according to claim 1, wherein each of the first and second optical waveguides includes a joined body of a core and a clad, and the core serves as a light guide path.   The optical waveguide device according to claim 6, wherein at least a part of the joined body is made of a polymer material.   The other end face of the first optical waveguide is formed on an inclined reflecting surface, and light is guided to the outside or the inside of the first optical waveguide through reflection by the inclined reflecting surface, and other optical components. The optical waveguide device according to claim 1, wherein the optical coupling is performed.   The optical waveguide device according to claim 1, and a base on which another optical component is mounted, wherein the other end surface of the first optical waveguide is optically coupled to the other optical component. An optical coupling device in which one optical waveguide is fixed to the base.   At the one end, the optical fiber or the second optical waveguide aligned with the first optical waveguide is bonded and fixed to the main surface on the light incident or exit side of the first optical waveguide. The optical coupling device according to claim 9.   The first optical waveguide is fixed in contact with one surface of a common support, and the optical fiber or the first optical fiber in a state aligned with the first optical waveguide is fixed to the other surface of the support. The optical coupling device according to claim 9, wherein the two optical waveguides are fixed in position.   The first optical waveguide is fixed in contact with the first support, the optical fiber or the second optical waveguide is fixed in contact with the second support, and the first optical waveguide and the position are fixed. The optical coupling device according to claim 9, wherein the first support body and the second support body are fixed to each other by contact or concave-convex fitting in the combined state.   The optical coupling device according to claim 12, wherein the second support is configured to be detachable from the first support.   The optical coupling device according to claim 9, wherein each of the first and second optical waveguides includes a joined body of a core and a clad, and the core serves as a light guide.   The optical coupling device according to claim 14, wherein at least a part of the joined body is made of a polymer material.   The other main surface of the first optical waveguide is in surface contact with the base on the opposite side of the optical fiber or the second optical waveguide, and the convex portion or the concave portion formed on the other main surface side, The optical coupling device according to claim 9, wherein a concave portion or a convex portion formed on the substrate side is fitted to each other.   The optical coupling device according to claim 16, wherein the convex portion is formed on a clad material on the other main surface side of the first optical waveguide.   17. The optical coupling device according to claim 16, wherein the convex part and the concave part used for the concave-convex fitting have opposite cross sections, and the convex part and the concave part have inclined surfaces having substantially the same inclination angle.   17. The optical coupling device according to claim 16, further comprising a guide mechanism for guiding at least one of the optical waveguide device and the base when the first optical waveguide is fixed at least in position relative to the base.   The light according to claim 19, wherein the guide mechanism includes guide pins or guide holes provided on the optical waveguide device side and the base body side, respectively, and includes a fitting mechanism between the guide pins and the guide holes. Coupling device.   The first optical waveguide and the base are in surface contact with each other on the main surface of the first optical waveguide opposite to the common support or the first support according to claim 11 or 12. And the common support or the first support and the base are in contact with each other, and the optical waveguide device and the other optical component are aligned by the contact, and the common to the base The optical coupling device according to claim 9, wherein the support body or the contact surface of the first support body is formed at a position separated from the other end face of the first optical waveguide by a predetermined distance. .   The optical coupling device according to claim 9, wherein a concave portion is formed in the base, and a light emitting or light receiving element which is the other optical component is fixed at a predetermined position in the concave portion.   The other end face of the first optical waveguide is formed as an inclined reflecting surface, and light is guided to the inside or the outside of the first optical waveguide through reflection by the inclined reflecting surface, and the other The optical coupling device according to claim 22, wherein the optical coupling device is configured to perform optical coupling with an optical component.   The optical coupling device according to claim 9, wherein the optical waveguide device is configured to be detachable from the base.   The optical coupling device according to claim 9, wherein the other optical component is a light emitting element, a light receiving element, an optical fiber, or a planar optical waveguide.

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