JP2006030224A - Optical waveguide and optical coupling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical coupling device in which a processing error generated when performing processing for exposing a core end portion of an optical waveguide is not included in an alignment error between the optical waveguide core end portion and another optical component, and such light. To provide an optical waveguide that enables the fabrication of a coupling device.
An optical waveguide 1 is a joined body of clads 2 and 4 and a core 3 serving as a light guide. The end face 6 of the optical waveguide 1 is formed on a reflecting surface inclined at approximately 45 degrees by dicer processing, and the optical waveguide 1 is optically coupled to the optical element 26 through reflection by the inclined end face 6. By a similar dicer process, a V-shaped groove 8 as an alignment marker is formed at a position away from the upper end 7 of the inclined end face 6 by a predetermined distance 9 at the upper part of the optical waveguide 1, and the V-shaped groove 8 is used. The optical waveguide 1 is accurately aligned with the support 11 by the concave-convex fitting. The support 11 is provided with an alignment means with the mounting substrate on which the optical element 26 is mounted at a position away from the position of the concave-convex fitting by a predetermined distance.
[Selection] Figure 1

Description

  The present invention is useful in an optical wiring system, and aligns an optical waveguide and another optical component (such as a light-emitting element, a light-receiving element, an optical fiber, or an optical waveguide), fixes the position on a support, and connects the optical path. The present invention relates to an optical coupling device and a manufacturing method thereof.

  Until now, information transmission over a relatively short distance, such as between boards in electronic equipment or between chips in a board, has been performed mainly by electrical signals, but in order to further improve the performance of integrated circuits. Therefore, 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 transmission of signals over a short distance such as between chips. It is possible to construct an optical transmission / communication system in which an optical waveguide is provided on a substrate, and a transmission path for signal-modulated laser light or the like is used.

  In such an optical wiring system, an optical coupling device that aligns an optical waveguide and connects an optical path by aligning the optical waveguide with another optical component (such as a light emitting element, a light receiving element, an optical fiber, or an optical waveguide) 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 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.

  In order to optically couple a planar light emitting or light receiving element and an optical waveguide, the end surface of the optical waveguide core is formed on a light reflecting surface inclined at 45 degrees, and light is transmitted into the optical waveguide by optical path conversion using the inclined end surface. Alternatively, it is common to optically couple an optical element and an optical waveguide that are guided to the outside and disposed opposite to the inclined end surface.

  There are several methods for forming the optical waveguide having the 45-degree inclined end face (reflection surface), but it is easy to form by using dicing.

Now, in Patent Document 1 described later, since there are variations in the positions of the end faces of the semiconductor laser and the optical waveguide, problems that occur when alignment is performed using alignment markers are pointed out.
A solution has been proposed for a case where the semiconductor laser is an edge-emitting type and the end face of the optical waveguide is perpendicular to the optical waveguide core.

  FIG. 8 is for explaining the problem pointed out in Patent Document 1 in the case where the end face of the optical waveguide is a 45-degree inclined end face (reflecting face). FIG. 10 is a flowchart showing a process of forming an optical coupling device 120 that forms an end face 106 inclined at 45 degrees at an end portion by dicing and connects a core 103 and an optical element 112 through reflection by the inclined end face 106.

  First, as shown in FIG. 8A, the layers of the lower clad 102, the core 103, and the upper clad 104 of the optical waveguide 101 are formed on the substrate 81. For example, a known polymer material having a different refractive index is applied by spin coating or the like, and cured by pretreatment heating, ultraviolet irradiation, and posttreatment heating, whereby the respective layers are sequentially laminated. At this time, the core material is patterned into the shape of the core 103.

  Further, after the core 103 is formed, the optical waveguide side marker 105 is formed by a method such as vapor deposition of a metal material on the upper surface of the lower clad 102 where the core 103 is not formed. The optical waveguide side marker 105 is used as a reference when the inclined end face 106 is formed on the optical waveguide 101 or when the optical waveguide 101 and the optical element 112 are aligned.

  Next, as shown in FIG. 8 (b), a 45 ° oblique process is performed by dicing with a V-shaped blade to form an inclined end face 106 on the optical waveguide 101, and the other end is also desired. Cut into shapes. At this time, the position where the inclined end face 106 is formed is determined at a position separated by a predetermined distance 107 from the optical waveguide side marker 105 with reference to the optical waveguide side marker 105. However, even if the center position of the dicing is correctly determined with reference to the optical waveguide side marker 105, as shown by a dotted line in FIG. The position where 108 is formed shifts to the left in FIG. 8B and has an error 109 with respect to the optical waveguide side marker 105. Actually, it is difficult to strictly control the cutting amount by the blade, and the position of the formed inclined end face 106 may cause an error 109 exceeding ± 10 μm, reflecting the variation of the cutting amount.

  Next, as shown in FIG. 8C, the position of the optical waveguide 101 is fixed to the mounting substrate 111 on which the optical element 112 is mounted, and the optical coupling device 120 is formed. At this time, for example, in the image observation using a CCD (Charge Coupled Device) camera and a microscope, the optical waveguide side marker 105 and the mounting substrate side marker 113 used as a reference for positioning the optical element 112 are simultaneously observed. Meanwhile, the mounting position of the optical waveguide 101 is positioned.

  According to the above method, even if the optical waveguide side marker 105 and the optical element 112 or the mounting substrate side marker 113 used as a positioning reference thereof are positioned without error, the position of the inclined end surface 106 is Since there is an error 109 with respect to the optical waveguide side marker 105, an alignment error having the magnitude of the error 109 is generated between the inclined end face 106 and the optical element 112.

  For example, when the cross section of the core 3 is a square of 40 μm × 40 μm, if the alignment error with the optical element 112 exceeds ± 10 μm, an optical coupling loss of 1 dB or more occurs, which is unacceptable. is there.

  Although the example in which the inclined end face 106 is formed by dicing has been described with reference to FIG. 8, the position of the end to be formed is determined based on the position when the end of the core is exposed by positioning based on a reference point such as a marker. Since there is more or less processing error with respect to the point, if the optical waveguide and other optical components are aligned based on this reference point after that, the alignment between the optical waveguide core end and the other optical components is performed as described above. Processing error is necessarily included.

  Patent Document 1 proposes a solution for the case where the semiconductor laser is an edge-emitting type and the end face of the optical waveguide is perpendicular to the optical waveguide core, but applicable objects are limited. For example, the present invention is not applicable when the optical element is a planar light emitting / receiving element and the end face of the optical waveguide is an inclined reflecting surface.

  In addition, as a method of alignment without using a marker, the optical element is actually operated, the position of the optical element is adjusted while actually observing the intensity of the signal light, and the position is fixed where the optical coupling is optimal. However, in this method, there is a problem that the optical element has to be driven, the alignment is very troublesome, and is not suitable for mass production.

Japanese Patent Laid-Open No. 11-337779 (page 2-5, FIGS. 1-4)

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a processing error that occurs when performing processing to expose the core end portion of the optical waveguide. An object of the present invention is to provide an optical coupling device that is not included in an alignment error with a component, and an optical waveguide that makes it possible to manufacture such an optical coupling device.

  That is, the present invention has an end face formed by processing that exposes an end portion of the core in an optical waveguide composed of a joined body of a core and a clad, and the edge portion of the processed end surface is used for alignment. The optical waveguide is optically coupled with another optical component, and the end of the core and the other optical component are aligned with each other. This relates to the optical coupling device.

  According to the present invention, the optical waveguide is formed of a joined body of a core and a clad, and has a processed end surface formed by processing that exposes an end portion of the core. The optical component is optically coupled. At this time, the end portion of the core and the other optical component are aligned based on the edge portion of the processed end face. For this reason, there is no room for the position error of the processed end face generated when forming the processed end face to enter the alignment error.

  In the optical waveguide of the present invention, it is preferable that a marker is provided with reference to the edge portion of the processed end surface, and the end portion of the core and the optical component are aligned by the marker. This is because when the edge portion is used as a location for detecting the position of the processing end face, detection is easy, and as a result, accuracy and efficiency are improved. In addition, if the marker is newly formed on the basis of the edge portion, the marker can be aligned with the end portion of the core without including the position error of the processing end surface generated when forming the processing end surface. The marker can be used.

  Further, the processed end face is preferably formed by cutting. As a method for forming the optical waveguide, there is a method by stamping molding or the like, but a method of cutting the optical waveguide layer formed on the substrate by cutting may be simple. Moreover, since this method is a method in which processing errors are likely to occur, the present invention can be applied most effectively.

  Moreover, it is preferable that the processed end face of the optical waveguide forms an inclined reflecting surface. Accordingly, light can be guided to the outside or the inside of the optical waveguide through the reflection by the inclined end face, and optical coupling with the other optical component can be formed. If the reflection by the inclined end face is used, it is possible to form optical coupling with other optical components while changing the direction of the optical path in a compact manner. Further, if a concave portion is provided in the mounting substrate and the light emitting or light receiving element which is the other optical component is fixed in the concave portion, there is an advantage that a surface light emitting type light emitting element or a surface light receiving type 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. It is easy to modulate and easy to implement. In addition, light receiving elements such as photodiodes are mainly surface light receiving elements, and are easy to mount.

  Further, it is preferable that the processing end surface is an inclined end surface formed by dicing, and the marker for alignment is provided on the upper side with the upper end of the cutting surface as the reference. At this time, the alignment marker is preferably a concave or convex portion formed on the surface, and the concave or convex portion is preferably formed by dicing. If it does in this way, it can carry out consistently from formation of the processing end face to formation of the position alignment marker with attaching to a device for dicing, and a series of processing can be performed accurately and efficiently. At this time, if the recess reaches the core, the propagation of light is hindered. Therefore, the depth of the recess is preferably less than the thickness of the upper clad.

  In addition, 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.

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

  The concave portion or the convex portion and the convex portion or the concave portion provided on the optical waveguide support corresponding to the concave portion or the concave portion are formed by concave and convex fitting, and the concave and convex fitting position is used as a reference. The optical waveguide support may be configured to be aligned with the other optical component by fitting the optical waveguide support to the support of the other optical component.

  Further, in the optical coupling device of the present invention, the concave portion or the convex portion described in claim 6 and the convex portion or the concave portion provided on the optical waveguide support corresponding to the concave portion or the concave portion are fitted into the concave and convex portions. The optical waveguide and the other optical component are aligned with each other by fitting the optical waveguide support and the support of the other optical component at the position relative to the position. It is good.

  The alignment by the concave / convex fitting is much simpler and more productive than the method of aligning the marker while observing the image, and as a result, the cost of the optical coupling device can be reduced. These will be specifically described in the first embodiment.

  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, a concave portion or a convex portion formed on the surface as an alignment marker and a convex portion or a concave portion provided on the optical waveguide support corresponding to the concave portion are formed to be unevenly fitted. The optical waveguide described in Item 9 is used, and the optical waveguide support is unevenly fitted to the support of another optical component at a position based on the concave / convex fitting position, whereby the optical waveguide and the other optical component are fitted. An example of an optical coupling device according to claim 12 and a manufacturing process thereof will be described with reference to FIGS.

  FIG. 1 is a plan view (a) and a sectional view (b) of the optical waveguide 1. In addition, sectional drawing (b) is sectional drawing in the position of the 1A-1A line | wire of top view (a). The optical waveguide 1 is composed of a joined body of a lower clad 2, a core 3 and an upper clad 4, and the core 3 as a light guide is sandwiched between the lower clad 2 and the upper clad 4. Although FIG. 1 shows an example in which four cores 3 are juxtaposed, the present invention is not limited to this, and the number of cores 3 included in the optical waveguide 1 may be single or plural.

  Each layer of the lower clad 2, the core 3 and the upper clad 4 of the optical waveguide 1 is formed, for example, 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 indexes of the clads 2 and 4, 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.

  The end surface 6 of the optical waveguide 1 is formed as a reflection surface inclined at approximately 45 degrees with respect to the main surface of the optical waveguide 1, and light is reflected inside the optical waveguide core 3 or reflected through the reflection by the inclined end surface 6. Optical coupling is formed with the optical element 26 that is guided to the outside and disposed oppositely as described later.

  In the upper part of the optical waveguide 1, a V-shaped groove 8 is formed as the concave portion serving as the alignment marker at a position away from the upper end 7 of the inclined end face 6 by a predetermined distance 9, and the optical waveguide support described below is formed. It is used for alignment by concavo-convex fitting with the body 11.

  FIG. 2 shows an uneven fitting between a V-shaped groove 8 formed as the concave portion, which is the alignment marker, on the upper portion of the optical waveguide 1 and a convex portion 13 provided on the optical waveguide support 11 corresponding thereto. FIG. 2 is a plan view (a) and a cross-sectional view (b) of an optical waveguide formed by the above. In addition, sectional drawing (b) is sectional drawing in the position of the 2A-2A line | wire of a top view (a). In this specification, such a composite of an optical waveguide layer and an optical waveguide support is also called an optical waveguide.

  The optical waveguide support 11 is formed by etching or the like from a silicon substrate or the like, and on one main surface side, a mountain-shaped convex portion 12 that fits with the V-shaped groove 8 formed in the optical waveguide 1, The guide hole 22 provided in the mounting substrate 21 and the guide pin 13 for engaging with the concave and convex portions are formed with high precision, and the position of the guide pin 13 is accurately at a position away from the convex portion 12 by a predetermined distance 14. It has been established.

  The material of the optical waveguide support 11 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.

  The optical waveguide 1 and the optical waveguide support 11 are accurately positioned by the concave-convex fitting between the V-shaped groove 8 and the mountain-shaped convex portion 12, and then integrated by, for example, bonding. The adhesive used at this time may be either thermosetting or ultraviolet curable.

  FIG. 3 is a plan view (a) and a cross-sectional view (b) of the optical coupling device according to the present embodiment. In addition, sectional drawing (b) is sectional drawing in the position of the 3A-3A line | wire of top view (a). An optical element array 26 is mounted as the other optical component on the mounting substrate 21 which is the support for the other optical component.

  The mounting substrate 21 is formed by etching or the like from a silicon substrate or the like, and has guide holes 22 that fit with the guide pins 13 of the optical waveguide support 11, an optical waveguide support surface 23, a recess 24 that fixes the optical element array 26, and The mounting board side marker 25 and the like are formed with high precision, and the optical element array 26 is mounted with being accurately positioned at a position away from the guide hole 22 by a predetermined distance 28 with the mounting board side marker 25 as a reference. ing.

  On the other hand, in the optical waveguide 1 integrated with the optical waveguide support 11, there is a convex portion 12 at a position away from the guide pin 13 by a predetermined distance 14 and further at a position away from the convex portion 12 by a predetermined distance 9. There is an upper end 7 of the inclined end face 6.

  Therefore, when the optical waveguide 1 and the mounting substrate 21 are fixed to each other by the concave / convex fitting between the guide pin 13 and the guide hole 22, as shown in FIG. 3B, the inclined end face 6 of the optical waveguide core 3. And the optical element 26 in the horizontal direction are automatically aligned.

  Further, since the optical waveguide 1 is held in a state where the main surface on the mounting substrate 21 side is in contact with the optical waveguide support surface 23, the optical element fixing recess 24 should be formed to an appropriate depth. The distance in the height direction between the inclined end face 6 of the optical waveguide core 3 and the optical element 26 is also automatically set to an appropriate size.

  In a state where the optical coupling is formed in this way, if the optical element 26 is a light emitting element, the light incident on the inclined end surface 6 from the light emitting portion 27 of the light emitting element is reflected by the inclined reflecting surface 6 and Guided inside. When the optical element 26 is a light receiving element, the light propagating through the core 3 is reflected by the inclined end surface 6 and guided to the light receiving portion 27 of the light receiving element. By using reflection by the inclined end face 6, there is an advantage that a surface light emitting type light emitting element having a light emitting part on the upper surface and a surface light receiving type light receiving element having a light receiving part on the upper surface can be used. For example, VCSEL (light emitting area size is 10 μm, for example) and surface-emitting LEDs are easy to manufacture, inexpensive, abundant in a variety of commercially available products, excellent in high frequency characteristics, easy to modulate, and easy to mount Easy. In addition, light receiving elements such as photodiodes are mainly surface light receiving elements, and are easy to mount.

  Note that the optical coupling device shown in FIG. 3 is detachable so that the optical waveguide side portion and the mounting substrate side portion can be separated or combined as necessary by inserting and removing the guide pins 13. A so-called connector-shaped optical coupling device can be obtained. 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.

  4 and 5 are flowcharts showing the steps of manufacturing the optical waveguide 1 and the optical coupling device. In addition, this figure is sectional drawing in the same position as sectional drawing (b) of FIG.

  First, as shown in FIG. 4A, the lower clad 2, the core 3 and the upper clad 4 of the optical waveguide 1 are formed on a substrate 81 such as silicon. For example, a known polymer material having a different refractive index is applied by spin coating or the like, and cured by pretreatment heating, ultraviolet irradiation, and posttreatment heating, whereby the respective layers are sequentially laminated. At this time, the core material is patterned into the shape of the core 3.

  Further, the end portion formation marker 5 is formed by a method such as vapor deposition of a metal material in a region where the core 3 is not formed on the upper surface of the lower clad 2 after the core 3 is formed.

  Next, as shown in FIG. 4B, an inclined end face (reflective surface) 6 is formed on the optical waveguide 1 by performing a 45 ° oblique process by performing a dicer process with a V-shaped blade. At this time, a position where the inclined end face 6 is formed is a position away from the end forming marker 5 by a predetermined distance with reference to the end forming marker 5. As described above, the position of the inclined end surface 6 that is actually formed may cause an error exceeding ± 10 μm with respect to the end forming marker 5 reflecting the variation in the cutting amount by the blade.

  Further, the other end face is cut into a desired shape. FIG. 4B shows an example in which the blade is cut perpendicularly with a normal blade, but the other end face may be formed on an inclined reflecting surface.

  Next, as shown in FIG. 4C, a V-shaped groove 8 is formed as the concave portion on the upper clad 4 by dicing with a V-shaped blade. The position where the V-shaped groove 8 is provided is a position separated by a predetermined distance 9 from the upper end 7 of the inclined end surface 6, which is the edge portion of the cutting surface, and is cut while detecting the upper end 7 with a dicer monitor. Thus, it can be determined with an accuracy of ± several μm.

  Next, as shown in FIG. 4D, the optical waveguide 1 is peeled from the substrate 81.

  Next, as shown in FIGS. 5E to 5F, the position of the optical waveguide 1 is fixed to the optical waveguide support 11 by concave-convex fitting.

  The optical waveguide support 11 is formed by etching or the like from a silicon substrate or the like, although a manufacturing process is not illustrated. On one main surface side, a V-shaped groove 8 formed in the optical waveguide 1 and a mountain-shaped convex portion 12 that fits in a concave-convex manner, and a guide pin that fits in a guide hole 22 provided in the mounting substrate 21 13 is formed with high accuracy, and the position of the guide pin 13 is accurately determined at a position away from the convex portion 12 by a predetermined distance 14.

  The material of the optical waveguide support 11 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.

  The optical waveguide 1 and the optical waveguide support 11 are accurately positioned by the concave-convex fitting between the V-shaped groove 8 and the mountain-shaped convex portion 12, and then integrated by, for example, bonding. The adhesive used at this time may be either thermosetting or ultraviolet curable.

  Next, as shown in FIGS. 5 (f) to 5 (g), the optical waveguide 1 is positioned on the mounting substrate 21 by concave and convex fitting between the guide pins 13 of the optical waveguide support 11 and the guide holes 22 of the mounting substrate 21. Fix it.

  Although not shown in the drawings, the mounting substrate 21 is formed by etching a semiconductor substrate such as a silicon substrate, and guide holes 22 that are unevenly engaged with the guide pins 13 of the optical waveguide support 11, an optical waveguide support surface 23, and an optical element array. The concave portion 24 for fixing 26, the mounting substrate side marker 25, and the like are formed with high accuracy. The optical element array 26 is accurately positioned and mounted at a position away from the guide hole 22 by a predetermined distance 28 with the mounting board side marker 25 as a reference.

  The material of the mounting substrate 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.

  As described above, according to the present embodiment, after the end surface (reflecting surface) inclined at 45 degrees is cut by the dicer, the alignment marker is formed with reference to the upper end of the cutting surface. Regardless of the position error of the 45-degree inclined end face that occurs when the 45-degree inclined end face is formed, accurate alignment with the inclined end face can be performed using the alignment marker.

  In addition, the 45 ° inclined end surface is formed by dicing using a V-shaped dicing blade, and the alignment marker is also formed by dicing using a V-shaped dicing blade. Therefore, the optical waveguide is mounted on a dicing apparatus. As it is, it can be performed consistently from the formation of the machining end face to the formation of the alignment marker, and a series of machining can be performed accurately and efficiently.

  Further, since the end face is inclined at 45 degrees, a surface light emitting / receiving element can be used.

  Further, the concave / convex fitting allows the optical waveguide and the surface light emitting / receiving element to be accurately aligned with high accuracy. This method is much simpler and more productive than the method of aligning the marker while observing the image, and as a result, the cost of the optical waveguide device can be reduced.

  The present invention can be used for alignment of an optical waveguide sheet and a submount for an optical waveguide sheet in an optical coupling device described in Japanese Patent Application No. 2004-105833.

Embodiment 2
The second embodiment is based on the optical waveguide and the optical coupling device based on the first embodiment, but in the first embodiment, the optical waveguide core end portion and the optical element, which are formed by the concave and convex fitting between the guide pin and the guide hole, are as follows. This is an example of an optical waveguide and an optical coupling device in which the alignment is performed by contact (butting) of the contact surface. The following description will be given with emphasis on the changes from the first embodiment.

  FIG. 6 is a cross-sectional view of the optical coupling device according to the second embodiment. This cross-sectional view is a cross-sectional view at a position corresponding to the cross-sectional view (b) of FIG.

  The optical waveguide 1 is the same optical waveguide 1 that is formed of a joined body of the lower clad 2, the core 3, and the upper clad 4 as in the first embodiment.

  The end surface 6 of the optical waveguide 1 is formed as a reflection surface inclined at approximately 45 degrees with respect to the main surface of the optical waveguide 1, and light is reflected inside the optical waveguide core 3 or reflected through the reflection by the inclined end surface 6. Optical coupling is formed with the optical element 46 that is guided to the outside and arranged oppositely.

  In the upper part of the optical waveguide 1, a V-shaped groove 8 is formed as the concave portion serving as the alignment marker at a position away from the upper end 7 of the inclined end face 6 by a predetermined distance 9, and the optical waveguide support described below is formed. It is used for alignment by uneven fitting with the body 31.

  The optical waveguide support 31 is formed by etching or the like from a silicon substrate or the like, and a mountain-shaped convex portion 32 that is concavo-convexly engaged with the V-shaped groove 8 formed in the optical waveguide 1 is provided on one main surface side. Further, a contact surface 33 that contacts the contact surface 42 provided on the mounting substrate 41 is provided on the front side surface. The convex portion 32 and the contact surface 33 are formed with high accuracy, and the position of the contact surface 33 is accurately determined at a position away from the convex portion 32 by a predetermined distance 34.

  The optical waveguide 1 and the optical waveguide support 31 are accurately aligned by the concave-convex fitting of the V-shaped groove 8 and the mountain-shaped convex portion 32, and then integrated by, for example, bonding. The position of the abutment surface 33 is accurately determined at a position away from the convex portion 32 by a predetermined distance 34, and the position of the V-shaped groove 8 that is concavo-convexly engaged with the convex portion 32 is the upper end 7 of the inclined end surface 6. Therefore, the position of the contact surface 33 is accurately determined at a position away from the upper end 7 of the inclined end face 6 by a predetermined distance. Will be.

  On the other hand, the mounting substrate 41 is formed by etching or the like from a silicon substrate or the like, and includes a contact surface 42 that contacts the contact surface 33 of the optical waveguide support 31, an optical waveguide support surface 43, and a recess 44 that fixes the optical element 46. The mounting board side marker 45 and the like are formed with high accuracy. The optical element 46 is accurately positioned and fixed at a position away from the contact surface 42 by a predetermined distance 47 with the mounting board side marker 45 as a reference.

  In order to align and fix the optical waveguide 1 integrated with the optical waveguide support 31 to the mounting substrate 41, first, the optical waveguide 1 is mounted on the mounting substrate so that the main surface thereof is in contact with the optical waveguide support surface 43. Next, the optical waveguide 1 and the optical waveguide support 31 are moved in the left-right direction in the drawing in a state where the optical waveguide 1 and the optical waveguide support surface 43 are in contact with each other. The contact surface 33 and the contact surface 42 of the mounting substrate 41 are brought into contact with each other.

  The upper end 7 of the inclined end surface 6 is at a position accurately spaced from the contact surface 33 by a predetermined distance, and the optical element 46 is at a position accurately spaced from the contact surface 42 by a predetermined distance. Accordingly, when the optical waveguide 1 and the mounting substrate 21 are fixed to each other by the above-described contact, as shown in FIG. 6, the horizontal position between the inclined end surface 6 of the optical waveguide core 3 and the optical element 46 is Aligned automatically. Similarly, alignment in the depth direction is also performed by contact of a contact surface (not shown) in the depth direction of FIG.

  Further, since the optical waveguide 1 is held in a state in which the main surface on the mounting substrate 41 side is in contact with the optical waveguide support surface 43, if the optical element fixing recess 44 is formed to an appropriate depth. The distance in the height direction between the inclined end face 6 of the optical waveguide core 3 and the optical element 46 is also automatically set to an appropriate size.

  In this way, perfect alignment in the three-dimensional direction is performed, and optical coupling between the inclined end face 6 of the optical waveguide core 3 and the optical element 46 is realized.

  At this time, if the optical element 46 is a light emitting element, the light incident on the inclined reflecting surface 6 from the light emitting portion of the light emitting element is reflected by the inclined reflecting surface 6 and guided into the core 3. When the optical element 46 is a light receiving element, the light propagating through the core 3 is reflected by the inclined reflecting surface 6 and guided to the light receiving part of the light receiving element. Thus, a surface-emitting light-emitting element having a light-emitting portion on the upper surface or a surface-receiving light-receiving element having a light-receiving portion on the upper surface can be used.

  The optical coupling device according to the present embodiment is different from the first embodiment only in the method for aligning the optical waveguide support and the mounting substrate by self-arrangement based on the outer shape. Needless to say, the same effect as described in the first embodiment can be expected.

  That is, according to the present embodiment, after the end surface (reflecting surface) inclined at 45 degrees is cut by the dicer, the alignment marker is formed with the upper end of the cutting surface as a reference, so the 45-degree inclined end surface is formed. Regardless of the position error of the 45-degree inclined end face that occurs at this time, accurate alignment with the inclined end face can be performed using the alignment marker.

  In addition, the 45 ° inclined end surface is formed by dicing using a V-shaped dicing blade, and the alignment marker is also formed by dicing using a V-shaped dicing blade. Therefore, the optical waveguide is mounted on a dicing apparatus. As it is, it can be performed consistently from the formation of the machining end face to the formation of the alignment marker, and a series of machining can be performed accurately and efficiently.

  Further, since the end face is inclined at 45 degrees, a surface light emitting / receiving element can be used.

  In addition, the contact between the contact surfaces allows the optical waveguide and the surface light emitting / receiving element to be accurately aligned with high accuracy. This method is much simpler and more productive than the method of aligning the marker while observing the image, and as a result, the cost of the optical waveguide device can be reduced.

Embodiment 3
In the third embodiment, the alignment between the optical waveguide core end and the optical element is not performed by the concave-convex fitting as in the first and second embodiments. For example, a CCD (Charge Coupled Device) camera and a microscope are used. The mounting substrate 51 while simultaneously observing the lower end (edge portion) 10 of the inclined end surface 6 of the optical waveguide 1 and the optical element array 56 or the mounting substrate side marker 55 used as a positioning reference in the image observation. A position of the optical waveguide 1 is fixed on the optical coupling device to form an optical coupling device.

  This embodiment is directly contrasted with the conventional method for manufacturing an optical coupling device shown in FIG. 8C, but is not the optical waveguide side marker 105 but the lower end (edge portion) 10 of the inclined end face 6. Therefore, it is not affected by the position error generated when the inclined end face 6 is formed.

  This method does not have a high efficiency of alignment compared with the method of aligning by uneven fitting or contact, but has the advantage that it is not necessary to provide means for uneven fitting or contact and an optical waveguide support. Have

  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.

  The optical coupling device of the present invention is preferably 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 has high productivity and low cost. Moreover, it can contribute to the construction of a high-performance optical transmission / communication system.

It is the top view (a) and sectional drawing (b) of an optical waveguide based on Embodiment 1 of this invention. The top view (a) and sectional drawing (b) of the optical waveguide integrated with the optical waveguide support body are the same. The top view (a) and sectional drawing (b) of an optical coupling device are the same. It is a flowchart which shows the manufacturing process of an optical waveguide and an optical coupling device equally. It is a flowchart which shows the manufacturing process of an optical waveguide and an optical coupling device equally. It is sectional drawing of the optical coupling device based on Embodiment 2 of this invention. It is sectional drawing of the optical coupling device based on Embodiment 3 of this invention. It is a flowchart which shows the conventional process of forming an inclined end surface in the edge part of an optical waveguide, and producing an optical coupling device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical waveguide, 2 ... Lower clad, 3 ... Core, 4 ... Upper clad,
5 ... end forming marker, 6 ... end face inclined at 45 degrees (reflective surface), 7 ... upper end of the inclined end face,
8 ... V-shaped groove, 9 ... predetermined distance, 10 ... lower end (edge portion) of the inclined end surface,
DESCRIPTION OF SYMBOLS 11 ... Optical waveguide support body, 12 ... Convex part, 13 ... Guide pin, 14 ... Predetermined distance,
21 ... Mounting substrate, 22 ... Guide hole, 23 ... Optical waveguide support surface, 24 ... Recess for fixing optical element,
25 ... mounting board side marker, 26 ... optical element array, 27 ... light receiving / emitting part of optical element array,
28 ... predetermined distance, 31 ... optical waveguide support, 32 ... convex, 33 ... guide pin,
34 ... predetermined distance, 41 ... mounting substrate, 42 ... guide hole, 43 ... optical waveguide support surface,
44: concave portion for fixing an optical element, 45 ... mounting board side marker, 46 ... optical element array,
47 ... predetermined distance, 51 ... mounting substrate, 53 ... optical waveguide support surface, 54 ... optical element fixing recess,
55 ... Mounting substrate side marker, 56 ... Optical element array, 81 ... Substrate, 101 ... Optical waveguide,
102 ... lower clad, 103 ... core, 104 ... upper clad,
105 ... Optical waveguide side marker, 106 ... End face (reflective surface) inclined at 45 degrees,
107 ... predetermined distance, 108 ... inclined end face when the cutting depth becomes too large,
109 ... error, 111 ... mounting board, 112 ... optical element, 113 ... mounting board side marker,
120 ... Optical coupling device

Claims (12)

  An optical waveguide comprising a joined body of a core and a clad has an end surface formed by processing for exposing the end portion of the core, and an edge portion of the processed end surface is used for alignment. , Optical waveguide.   The optical waveguide according to claim 1, wherein a marker is provided with reference to the edge portion, and the end portion of the core and the optical component are aligned by the marker.   The optical waveguide according to claim 1, wherein the processed end face is formed by cutting.   The optical waveguide according to claim 3, wherein the processed end surface forms an inclined reflecting surface.   The optical waveguide according to claim 2, wherein the processed end surface is an inclined end surface formed by dicing, and the marker for alignment is provided at an upper portion with the upper end of the cut surface as the reference.   The optical waveguide according to claim 5, wherein the alignment marker is a concave portion or a convex portion formed on a surface.   The optical waveguide according to claim 6, wherein the concave portion or the convex portion is formed by dicing.   The optical waveguide according to claim 7, wherein a depth of the concave portion is less than a thickness of the upper clad.   The concave portion or the convex portion and the convex portion or the concave portion provided on the optical waveguide support corresponding to the concave portion or the concave portion are formed by concave and convex fitting, and the concave and convex fitting position is used as a reference. 7. The optical waveguide support according to claim 6, wherein the optical waveguide support is configured to be aligned with the support of the other optical component so that the alignment with the other optical component is performed. Optical waveguide.   The optical waveguide according to claim 1, wherein at least a part of the joined body is made of a polymer material.   The optical waveguide according to any one of claims 1 to 10 and another optical component are optically coupled, and the end of the core and the other optical component are aligned. Coupling device.   The concave portion or the convex portion according to claim 6 and the convex portion or the concave portion provided in the optical waveguide support corresponding to the concave portion or the concave portion are concavely and convexly fitted, and at the position based on the concave and convex fitting position, the light guide The optical coupling device according to claim 11, wherein the optical waveguide and the other optical component are aligned by the concave-convex fitting of the waveguide support and the support of the other optical component. .

Images