JP6268918B2 - Optical fiber connection structure, optical fiber connection method, and optical module - Google Patents

Description

  The present invention relates to an optical fiber connection structure, an optical fiber connection method, and an optical module.

  Optical signals are suitable for high-speed and large-capacity signal transmission, and optical signals are put into practical use in long-distance backbone communication systems. Even in information system devices such as computers, optical signals have already been put into practical use between devices due to the increase in signal speed, and the introduction of optical signals into devices and boards is now in the field of view. As a wiring member for connecting distant positions, an optical fiber is superior in terms of performance and price. On the other hand, an optical signal processing part, for example, an optical transceiver, an optical coupler / splitter, an AWG (Arrayed Waveguide Grating) or the like is preferably formed as an optical waveguide. Furthermore, recently, silicon photonics is also being used. Silicon photonics has an advantage that the same function can be formed in a very small area by finely processing silicon in a semiconductor manufacturing process. The optical waveguide component alone formed on the substrate has limited applications, and by connecting to an optical fiber, an optical signal processed by the optical waveguide can be transmitted to a target location.

  As the function and integration degree of the optical waveguide components are improved, the number of optical fibers to be connected has been remarkably increased. Usually, an optical waveguide and an optical fiber are connected using a component called a fiber array in which optical fibers are bonded and fixed in V grooves formed at regular intervals. In order to connect the optical waveguide and the optical fiber with low loss, it is necessary to precisely control the positional relationship between the two. Alignment accuracy within 1 μm in single mode and within several μm in multimode is required. A fiber array in which optical fibers are aligned has the merit that many optical fibers can be connected at the same time. However, in order to match the target position accuracy, not only three-axis movement of XYZ but also rotation of each axis is included. A total of 6 axes of precision alignment is required. In particular, as the number of optical fibers aligned with the fiber array increases, the accuracy in the rotational direction becomes much more severe.

  Many proposals have been made to achieve both positional accuracy and ease of optical fiber connection work by forming a guide V-groove on the optical waveguide substrate side.

  In the first group, V-grooves for aligning optical fibers are formed on the substrate. In this case, since the V-groove needs to be terminated at the end face of the optical waveguide core, it is formed by etching, particularly silicon anisotropic etching. When anisotropic etching is used, a V-shaped groove having a precise shape determined by the angle of the crystal plane can be obtained, and a V-shaped groove having an accurate dimension can be formed by defining an etching pattern using a photolithography technique. However, a problem arises as to which of the optical waveguide and the V-groove is formed first on the substrate. When the V-groove is formed first, it is difficult to form a core of several μm to several tens of μm on the edge of a huge groove of 100 μm or more without disordering the shape. In order to solve this problem, a method of forming a core by temporarily filling a V groove with a resin (see, for example, Patent Document 1), or a method of forming a core by covering the V groove (for example, Patent Document 2). Have been proposed).

  However, the method of temporarily filling the V-groove takes time and is not sufficient. In the case of resin filling, complete smoothness cannot be expected, and the core shape is disturbed. Even when the V-groove is covered, the formation of the core is likely to be disturbed by the lid unless the positional accuracy of the lid and the thickness of the lid are controlled.

Conversely, there is a method of forming a V-groove later (see, for example, Patent Document 3). However, anisotropic etching of silicon needs to be boiled for a long time in a high-concentration alkaline solution, and the material of the optical waveguide that can withstand this is extremely limited. Silica (SiO ₂ ) -based optical waveguides are examples of materials that can withstand wet processing, but even these may be damaged if strong protective measures are not taken.

  Another disadvantage of using anisotropic etching of silicon is that the wall surface of the optical waveguide core is also beveled and the optical fiber cannot be close to the core. For this reason, vertical grooves are formed by another processing (for example, see Patent Document 4), or the end face of the optical fiber is processed into a shape corresponding to the slope of the optical waveguide core (for example, see Patent Document 5). Since the former requires two types of processing, the formation process takes time. In the latter case, it is difficult to process the tip of the optical fiber itself, and it is necessary to arrange the optical fiber in the V-groove in the same direction in the rotation direction.

  Thus, although the effect is high if the optical fiber alignment V-groove can be formed on the optical waveguide substrate, there is a problem that the formation itself is very difficult.

  In the second group, guide groove V grooves are formed on the optical waveguide substrate. In this case, the V-groove is formed on both sides of the core, and it is not necessary to accurately terminate the groove at the end surface of the core. Therefore, the V-groove can be formed by simple grinding (grinding). However, since grinding is a machining process, high accuracy cannot be expected in the formation position and depth of the V-groove. For this reason, it is difficult to obtain the accuracy required for optical fiber connection unless extremely precise adjustment is performed.

  If the V groove for the guide pin is formed by anisotropic etching of silicon as in the first group, the necessary accuracy can be ensured. However, the same problem occurs as when fiber grooves are formed on the substrate. If the V-groove is formed first, the flow changes in the groove when spin coating is applied to the photoresist or the optical waveguide resin, and it is difficult to uniformly apply to the front surface of the substrate. If the V-groove is formed later, the material of the optical waveguide that can withstand the wet treatment as described above is poor.

JP 2006-119627 A JP-A-8-313756 JP 2005-308918 A Japanese Patent Laid-Open No. 1-126698 JP 2004-151391 A

  Therefore, it is an object to provide a structure that facilitates connection of an optical fiber to an optical waveguide and a manufacturing method thereof.

In one aspect, the optical fiber connection structure is:
A guide chip mounted on an optical waveguide substrate on which an optical waveguide is formed and having a first slope extending in parallel with the optical waveguide;
A fiber storage substrate that holds an array of optical fibers and has a second slope corresponding to the first slope of the guide tip;
The fiber housing substrate includes a first portion that fits with the first inclined surface of the guide chip on the optical waveguide substrate at the second inclined surface, and the optical fiber positioned outside the optical waveguide substrate. The second portion holds the optical fiber in a groove formed at a constant pitch.

  Connection of the optical fiber to the optical waveguide is facilitated.

1 is a schematic perspective view of an optical module using the optical fiber connection structure of Example 1. FIG. 1 is a configuration diagram of a fiber array used in the optical fiber connection structure of Example 1. FIG. It is a figure which shows the optical fiber connection structure of Example 1, and its connection process. It is a figure which shows the optical fiber connection structure of Example 1, and its connection state. FIG. 6 is a connection process diagram using an optical fiber connection structure which is a modification of the first embodiment. 6 is a configuration diagram of a fiber array used in the optical fiber connection structure of Example 2. FIG. It is a figure which shows the optical fiber connection structure of Example 2, and its connection process. It is a figure which shows the optical fiber connection structure of Example 2, and its connection state.

  The optical fiber connection structure of the embodiment connects an optical fiber held in a fiber array to an optical waveguide formed on an optical waveguide substrate. The optical fiber connection structure includes a fiber array and a guide chip disposed on the optical waveguide substrate. The first inclined surface is provided on the side wall of the guide chip, and the second inclined surface is provided on the side surface of the fiber storage substrate of the fiber array. The optical fiber is aligned with and connected to the optical waveguide by utilizing the fitting of the first slope and the second slope. Thus, the optical fiber can be accurately connected to the optical waveguide with a simple configuration.

  In particular, when the same material is used for the guide chip and the optical fiber storage substrate and the first and second inclined surfaces are formed using the same crystal plane, the first etching is performed by anisotropic etching without using a precise processing tool. The first slope and the second slope can be accurately matched. Moreover, also when forming a guide chip and an optical fiber accommodation board | substrate by injection molding using a metal mold | die, a 1st slope and a 2nd slope can be made to correspond exactly.

  FIG. 1 is a schematic perspective view of an optical fiber connection structure 10A of Example 1 and an optical module 1A using the same. The optical fiber transmission line connection structure 10 </ b> A includes a guide chip 13 disposed on the optical waveguide substrate 11 and a fiber array 20. The fiber array 20 includes one or more optical fibers 21 and a fiber storage substrate 25 that stores the optical fibers 21. In order to hold the optical fiber 21 stably, a lid 27 that holds the optical fiber 21 together with the fiber storage substrate 25 may be included.

  In the first embodiment, a pair of guide chips 13 is used for the optical transmission line connection structure 10A. The guide chips 13 are arranged on both sides of the optical waveguide 12 formed on the optical waveguide substrate 11, and the fiber array 20 is inserted between the guide chips 13.

  The guide chip 13 has slopes 14 on surfaces facing each other across the optical waveguide 12. On the other hand, the fiber storage substrate 25 of the fiber array 20 has a slope 32 corresponding to the slope 14 of the guide chip 13 on the side surface. By fitting and sliding the inclined surface 32 of the fiber housing substrate 25 on the inclined surface 14 of the guide chip 13, the optical fiber 21 can be accurately positioned and connected to the optical waveguide 12.

  The fiber housing substrate 25 is fitted to the guide chip 13 on the optical waveguide substrate 11 in a region extending first from the lid 27. As will be described later, the optical fiber 21 extends to the vicinity of the center in the optical axis direction of the fiber storage substrate 25, and the tip of the optical fiber 21 slightly protrudes from the tip surface of the lid 27. As a result, when the fiber housing substrate 25 is inserted into the guide chip 13, the optical fiber 21 comes into contact with the end surface of the optical waveguide substrate 11, and the optical fiber 21 and the optical waveguide 12 are light-transmitted at the end surface of the optical waveguide substrate 11. Join.

  An optical module 1A using the optical transmission line connection structure 10A includes an optical waveguide substrate 11, an optical circuit 15 formed on the optical waveguide substrate 11, and an optical waveguide 12 extending from the optical circuit 15 to the end of the optical waveguide substrate 11. And an optical transmission line connection structure 10 </ b> A for connecting the optical fiber 21 to the optical waveguide 12 at the end of the optical waveguide substrate 11.

  Although not shown, the optical circuit 15 includes a light emitting device, an optical modulator, a light receiving element, an optical coupler / splitter, an AWG (Array waveguide Grating), and the like. The optical circuit 15 may be connected to the electronic component by electrical wiring (not shown). When the optical circuit 15 includes a waveguide circuit on the optical reception side and a waveguide circuit on the optical transmission side, the optical waveguide 12 for input to the optical circuit 15 and the optical waveguide 12 for output from the optical circuit 15. May be formed on the optical waveguide substrate 11. In that case, the optical transmission line connection structure 10A may be arranged for each of the input optical waveguide 12 and the output optical waveguide.

  2 to 4 are diagrams illustrating a connection process of the optical transmission line connection structure 10A according to the first embodiment. First, as shown in FIG. 2, the fiber array 20 is produced. In FIG. 2A, the optical fiber 21 is mounted on the fiber housing substrate 25. The fiber storage substrate 25 has V grooves 34 formed at a constant pitch on the fiber holding surface 31, and has slopes 32 corresponding to the slopes 14 of the guide chip 13 on both side walls of the fiber holding surface 31.

  The fiber storage substrate 25 is, for example, a silicon substrate. In this case, by using anisotropic etching of silicon, the V groove 34 having an accurate angle determined by the crystal plane of silicon can be formed. The width and depth of the V-groove 34 can be accurately controlled by using a crystal plane in combination with a photolithography technique. The side surface of the fiber storage substrate 25 is also etched simultaneously with the formation of the V-groove 34 to form the inclined surface 32. Since the position of the inclined surface 32 with respect to the V groove 34 is determined by the accuracy of photolithography, the positions of the inclined surfaces 32 on both side surfaces of the fiber storage substrate 25 are accurately defined with respect to the V groove 34.

  When the optical fiber 21 is mounted in the V-groove 34, the optical fiber 21 is arranged so that the tip of the optical fiber 21 is positioned at the approximate center of the fiber storage substrate 25. The optical fiber 21 is obtained by removing the coating of a tape core wire (not shown) and cutting the tip by a cleavage method or laser cutting, and the lengths thereof are uniform. The lid 27 is used to bond the optical fiber 21 while pressing it against the V-groove 34 of the fiber housing substrate 25. In the case of using a liquid or gel adhesive, the amount is appropriately adjusted so that the adhesive does not flow before the tip of the optical fiber 21. In the example of FIG. 2A, bonding is performed using adhesive films 23a and 23b.

  By holding the optical fiber 21 between the lid 27 and the fiber housing substrate 25 using the adhesive films 23a and 23b, the fiber array 20 shown in FIG. 2B is completed. In a general fiber array, the optical fiber is disposed up to the end of the V-groove, and the end face is polished. On the other hand, in the configuration of FIG. 2, the end face of the optical fiber 21 is located in the middle of the fiber storage substrate 25. By adopting the configuration shown in the figure, the region of the fiber housing substrate 25 where the optical fiber 21 is not mounted can be used as a bonding area to the surface of the optical waveguide substrate 11. Compared with the conventional configuration, the joint surface with the optical waveguide substrate 11 is increased, and the fixing is strong and less secularly changed.

  Further, the tip of the optical fiber 21 mounted in the V groove 34 protrudes beyond the tip of the lid 27. Thereby, the coupling between the optical fiber 21 and the optical waveguide 12 on the optical waveguide substrate 11 is ensured. Further, it is possible to prevent a part of the adhesives 23 a and 23 b from flowing out from the lid 27 and hindering the coupling between the optical fiber 21 and the optical waveguide 12.

  Next, in the step of FIG. 3, the guide chip 13 is mounted on the optical waveguide substrate 11, and the fiber array 20 is disposed above the optical waveguide substrate 11 with its fiber holding surface facing downward. The optical waveguide substrate 11 is, for example, a silicon substrate, and the optical waveguide 12 and the optical circuit 15 are formed using silicon photonics technology.

  The guide chip 13 is produced using a crystalline substrate such as silicon. The slope 14 of the guide tip 13 is formed by anisotropic etching using the crystal plane. As described above, by using the same crystal face of the same crystal material as that of the fiber storage substrate 25, the inclined surface 14 of the guide chip 13 and the inclined surface 32 of the fiber storage substrate 25 can be accurately matched. The pair of guide chips 13 are mounted on the optical waveguide substrate 11 with the inclined surfaces 14 facing the optical transmission path 14.

  The accuracy of core bonding between the core of the optical fiber 21 and the optical waveguide 12 is determined at the mounting position of the guide chip 13. An alignment mark is formed on the optical waveguide substrate 11 using a mask for forming the optical waveguide 12 on the optical waveguide substrate 11, and a high-precision flip chip bonder (made by Toray Engineering, OF2000, accuracy ± 0.5 μm) is used. Thereby, the positional accuracy of the guide chip 13 with respect to the optical waveguide 12 can be ensured.

  FIG. 3B is a cross-sectional view taken along the line AA ′ of FIG. The position of the inclined surface 32 of the side wall with respect to the V groove 34 of the fiber storage board 25 is precisely defined by the accuracy of photolithography. The position of the inclined surface 14 of the guide chip 13 with respect to the optical waveguide 12 of the optical waveguide substrate 11 is accurately defined by the precision of alignment mark formation by photolithography and the precision of the flip chip bonder. In addition, the angle of the inclined surface 32 of the fiber storage substrate 25 and the angle of the inclined surface 14 of the guide chip 13 are controlled by anisotropic etching using the same crystal plane.

  Next, in the process of FIG. 4, the fiber array 20 is slid in a state where the inclined surface 14 of the guide chip 13 and the inclined surface 32 of the fiber storage substrate 11 are aligned, and the end surface of the optical fiber 21 abuts against the end surface of the optical waveguide substrate 11. Adhere and fix. Thereby, the connection between the optical waveguide 12 and the optical fiber 21 is completed, and the optical module 1A is completed.

  4B is a cross-sectional view taken along the line BB ′ of FIG. 4A, and FIG. 4C is a cross-sectional view taken along the line CC ′ of FIG. As shown in FIG. 4B, the optical fiber core 21 a and the optical waveguide 12 coincide with each other at the end face of the optical waveguide substrate 11. As described above, the positional accuracy of the optical fiber in the arrangement direction (X direction) includes the positional accuracy of the inclined surface 32 with respect to the V-groove 34, the mounting positional accuracy of the guide chip 13 with respect to the optical waveguide 12, and the angle between the inclined surface 32 and the inclined surface 14. Secured by accuracy.

  The positional accuracy of the optical fiber core 21a in the height direction (Y direction) is determined by the position of the optical fiber 21 in the V-groove 34. In the first embodiment, anisotropic etching is performed using a specific crystal plane of the fiber housing substrate 25. Therefore, by specifying the width of the V groove 34 from the diameter of the optical fiber 21, the depth of the V groove is determined. . Therefore, the position of the optical fiber core 21a and the position of the optical waveguide 12 of the optical waveguide substrate 11 also coincide with each other in the height direction.

  As shown in FIG. 4C, the positional accuracy of the optical fiber core 21 a in the optical axis direction (Z direction) is such that the tip of the optical fiber 21 is located in the middle of the fiber housing substrate 25 and from the front surface 27 a of the lid 27. It is ensured by mounting so that the tip of the optical fiber 21 protrudes. By sliding and inserting the fiber storage substrate 25 between the inclined surfaces 14 of the guide chip 13, the optical fiber 21 moves in the Z direction, and the movement in the Z direction is performed when the tip of the optical fiber 21 hits the end surface of the optical waveguide substrate 11. finish. In this state, the optical module 1A is completed by bonding and fixing the fiber housing substrate 25 to the optical waveguide substrate 11.

  According to the configuration of the first embodiment, the optical fiber 21 can be aligned and connected to the optical waveguide 12 with a simple configuration.

  FIG. 5 is a schematic configuration diagram of an optical fiber connection configuration 10B as a modification of the first embodiment and an optical module 1B using the same. In the configuration of FIGS. 1 to 4, the fiber storage substrate 25 completely enters between the guide chips 13, and the fiber mounting surface of the fiber storage substrate 25 is in contact with the surface of the optical waveguide substrate 11 and slides.

  In the modification shown in FIG. 5, the V-groove 84 of the fiber housing substrate 75 is formed by grinding (grinding) into glass or the like instead of anisotropic etching of silicon. Since the V-groove 84 by grinding is simple, it is used for an inexpensive fiber array. The uniformity of the pitch and depth of the V-groove 84 is sufficient for optical fiber alignment applications, but the absolute value of the depth cannot be guaranteed. In other words, when the optical fibers 21 are aligned with the V-grooves 84 that are ground, the optical fibers 21 are evenly arranged. Not necessarily. For this reason, grinding is often used for conventional butt-joint type fiber arrays, but it is not generally used for applications where the accuracy of the groove shape is required.

  In the modification of FIG. 5, by using the accuracy of the pitch of the V-groove 84, an inexpensive grinding groove is applied to the V-groove 84 that requires shape accuracy. Specifically, as shown in FIG. 5A, at least two V-grooves 84 that are larger than the number of cores of the optical fiber 21 are formed. Cut the V-grooves outside the required number of groove arrays with a cutting line indicated by a broken line.

  As shown in FIG. 5B, as a result of the cutting, a slope 82 having the same slope shape as that of the V groove 84 is formed on a part of the side surface of the fiber housing substrate 75. The inclination of the inclined surface 14 of the guide chip 13 disposed on the optical waveguide substrate 11 is also adjusted to the inclination of the inclined surface 82 of the fiber housing substrate 75, that is, the inclined surface of the V groove 84. This can be realized by forming the guide chip 13 by cutting the substrate using the same blade as the formation of the V groove 84 or a large blade having the same angle. As described above, the mounting accuracy of the guide chip 13 on the optical waveguide substrate 11 is guaranteed by the accuracy of alignment mark formation by photolithography and the accuracy of the flip chip bonder.

  As shown in FIG. 5C, the fiber storage board 75 is fitted between the guide chips 13 with the fiber holding surface of the fiber storage board 75 facing down in the same manner as in FIG. 4, and the tip of the optical fiber 21 is the optical waveguide. The fiber storage board 75 is slid until it hits the end face of the board 11. Since the slope 82 on the side surface of the fiber storage board 75 and the slope 14 of the guide chip 13 substantially coincide with each other, the fiber storage board 75 in a state where the positions of the optical waveguide 12 and the optical fiber core 21a are aligned in the fiber arrangement direction (X direction). Are mounted on the optical waveguide substrate 11.

  The position of the core 21a of the optical fiber 21 in the height direction (Y direction) is determined by the position of the inclined surface 14 in the X direction of the guide chip 13. The positional accuracy of the slope 14 in the X direction is sufficiently ensured. Therefore, even when the absolute value of the depth of the V-groove 84 is different from the designed value, the optical fiber core 21a is made to fit in the Y direction by fitting the inclined surface 82 of the fiber storage board 75 to the inclined surface 14 of the guide chip 13. The optical waveguide 12 can be aligned. In this case, the surface of the fiber housing substrate 75 does not necessarily coincide with the surface of the optical waveguide substrate 11, and a space 85 may be generated. However, there is no problem as long as the height position of the optical fiber core 21 a matches the height position of the optical waveguide 12.

  FIGS. 6-8 is a figure which shows the optical fiber connection structure 30 of Example 2, and its connection process. In the first embodiment, the guide chips 13 having the slopes 14 are arranged on both sides of the optical waveguide 12 of the optical waveguide substrate 11. In the second embodiment, one guide chip 53 is disposed on the optical waveguide 12 of the optical waveguide substrate 11, and a groove 61 that fits with the guide chip 53 is formed in the fiber storage substrate 45.

  FIG. 6 is a diagram illustrating a configuration of the fiber array 40 used in the second embodiment. The fiber array 40 includes one or more optical fibers 21 and a fiber storage substrate 45 that stores the optical fibers 21. In order to hold the optical fiber 21 stably, a lid 47 that holds the optical fiber 21 together with the fiber storage substrate 45 may be included.

  The fiber housing substrate 45 includes a region where the V-groove 64 for receiving the optical fiber 21 is formed and a recess 61 formed in a region ahead of the region where the V-groove is formed. The lid 47 presses the optical fiber 21 against the fiber storage substrate 45 in the region where the V-groove 64 is formed. As means for fixing the optical fiber 21 to the fiber housing substrate 45, adhesive films 43a and 43b are used as shown in FIG. 6A, but the present invention is not limited to this example.

  As shown in FIG. 6B, the tip of the optical fiber 21 mounted on the fiber housing substrate 45 slightly protrudes forward from the lid 47. With this configuration, when the fiber housing substrate 45 is mounted on the optical waveguide substrate 11, the tip of the optical fiber 21 always abuts against the optical waveguide 12. Even if the adhesive material flows out, optical coupling between the tip of the optical fiber 21 and the optical waveguide 12 is ensured.

  The recess 61 is formed by digging a portion ahead of the region of the V groove 64 by anisotropic etching. As an example, the depth of the recess 61 is several hundred microns. The recess 61 has a slope 62 on its side wall. The slope 62 is formed using a specific crystal plane, and the angle of the slope 62 and the angle of the V groove 64 are substantially the same.

  In FIG. 7, the guide chip 53 is disposed on the optical waveguide 12 near the edge of the optical waveguide substrate 11. The fiber array 40 is disposed above the optical waveguide substrate 11 so that the fiber mounting surface faces the optical waveguide 12. The fiber array 40 and the guide chip 53 constitute the optical fiber connection structure 30. The optical waveguide 12 extends from the optical circuit 15 to the edge of the optical waveguide substrate 11 for transmission and reception of optical signals via the optical fiber 21.

  The guide chip 53 has a slope 54 on its side surface, and the slope 54 is positioned parallel to the optical axis of the optical waveguide 12. The inclined surface 54 of the guide chip 53 has the same inclination angle as the inclined surface 62 of the side wall of the recess 61 of the fiber storage substrate 45. The guide chip 53 is made of the same material as that of the fiber housing substrate 45 and anisotropic etching is performed using the same crystal plane, whereby the slope 54 having the same shape as the slope 62 of the recess 61 can be formed. The height of the guide tip 54 corresponds to the depth of the recess 61.

  As in the first embodiment, the mounting accuracy of the guide chip 54 on the optical waveguide substrate 11 is ensured by the alignment mark formation accuracy (not shown) and the flip chip bonder accuracy. The recess 61 of the fiber storage substrate 45 is placed on the guide chip 53, and the fiber storage substrate 45 is slid along the slope 54 of the guide chip 53, thereby mounting the fiber storage substrate 45 on the optical waveguide substrate 11.

  FIG. 8 shows a connection state between the optical fiber 21 and the optical waveguide 12. 8B is a DD ′ cross-sectional view of FIG. 8A, and FIG. 8C is a EE ′ cross-sectional view of FIG. 8A. As a result of sliding the fiber storage substrate 45 along the inclined surface 54 of the guide chip 53, the state where the tip of the optical fiber 21 is in contact with the optical waveguide 12 exposed on the end surface of the optical waveguide substrate 11 is shown. In this state, the fiber housing substrate 45 is bonded and fixed to the optical waveguide substrate 11.

  As shown in FIGS. 8B and 8C, the optical fiber core 21a and the optical waveguide 12 match in both the fiber arrangement direction and the height direction, and a stable connection is realized with multi-fibers. The configuration of the second embodiment has an advantage that only one guide chip 54 is required.

  With the configuration and method of the first and second embodiments, the alignment between the optical fiber and the optical waveguide is simplified using the guide chip. In addition, since a wide area of the fiber storage substrate (25, 75, 45) can be used for the bonding region with the optical waveguide substrate 11, the bonding becomes strong. Further, when the V-groove and the slope are formed using the crystal plane, the alignment accuracy is further improved.

The following notes are presented for the above explanation.
(Appendix 1)
A guide chip mounted on an optical waveguide substrate on which an optical waveguide is formed and having a first inclined surface (14, 54) extending in parallel with the optical waveguide;
A fiber storage substrate that holds an array of optical fibers and has a second slope corresponding to the first slope of the guide tip;
The fiber housing substrate includes a first portion that fits with the first inclined surface of the guide chip on the optical waveguide substrate at the second inclined surface, and the optical fiber positioned outside the optical waveguide substrate. An optical fiber connection structure, wherein the optical fiber is held in a groove formed at a constant pitch by the second portion.
(Appendix 2)
The guide chips are a pair of guide chips disposed on both sides of the optical waveguide, and the first inclined surface is at a position facing the optical waveguide,
The optical fiber connection structure according to appendix 1, wherein the second slope is formed on a side surface of the fiber storage substrate.
(Appendix 3)
The guide chip is one guide chip disposed on the optical waveguide,
The fiber housing substrate has a recess formed in the first portion;
The optical fiber connection structure according to appendix 1, wherein the second slope is formed on a side wall of the recess.
(Appendix 4)
The light according to any one of appendices 1 to 3, wherein the guide chip and the fiber storage substrate are formed of the same material, and the first inclined surface and the second inclined surface are formed of the same crystal plane. Fiber connection structure.
(Appendix 5)
The optical fiber connection structure according to any one of appendices 1 to 3, wherein the first inclined surface of the guide tip and the second inclined surface of the fiber storage substrate are formed by cutting.
(Appendix 6)
The optical fiber connection structure according to any one of appendices 1 to 5, wherein a tip end of the optical fiber is positioned in the vicinity of a boundary between the first portion and the second portion of the fiber housing substrate.
(Appendix 7)
An optical waveguide substrate having an optical circuit and an optical waveguide extending from the optical circuit;
The optical fiber connection structure according to any one of supplementary notes 1 to 6, which is disposed at an end of the optical waveguide substrate and connects the optical waveguide and an optical fiber;
An optical module.
(Appendix 8)
A guide chip having a first slope is disposed on an optical waveguide substrate on which an optical waveguide is formed so that the first slope is positioned in parallel with the optical waveguide,
Preparing a fiber storage substrate having a first portion having a second slope corresponding to the first slope and a second portion holding an optical fiber array behind the first portion;
The surface of the fiber storage substrate holding the optical fiber is directed to the optical waveguide substrate, the second inclined surface of the fiber storage substrate is slid onto the first inclined surface of the guide chip, and the tip of the optical fiber is Close to the end face of the optical waveguide,
When the tip of the optical fiber held by the second portion hits the end surface of the optical waveguide substrate, the fiber storage substrate is fixed to the optical waveguide substrate.
An optical fiber connection method.
(Appendix 9)
Preparing a pair of the guide chips, arranging the guide chips on both sides of the optical waveguide so that the first inclined surface is opposed to the optical waveguide,
Forming the second slope on a side surface of the fiber housing substrate;
The optical fiber connection according to appendix 8, wherein the first portion of the fiber housing substrate is inserted between the pair of guide chips, and the second inclined surface is slid on the first inclined surface. Method.
(Appendix 10)
The guide chip having the first slope on both side walls is disposed on the optical waveguide,
Forming a recess having the second slope on the first portion of the fiber housing substrate;
The optical fiber connection method according to appendix 8, wherein the recess and the guide chip are fitted to slide the second inclined surface onto the first inclined surface.
(Appendix 11)
The light according to appendix 8, wherein the first inclined surface and the second inclined surface are formed by anisotropic etching of the same crystal plane using the guide chip and the fiber storage substrate made of the same material. Fiber connection method.
(Appendix 12)
The light according to appendix 8, wherein the guide tip in which the first slope is formed by a cutting technique and the fiber storage substrate in which the second slope is formed by the same cutting technique as the first slope are used. Fiber connection method.

1A, 1B, 2 Optical modules 10A, 10B, 30 Optical fiber connection structure 11 Optical waveguide substrate 12 Optical waveguide 13, 53 Guide chip 14, 54 Slope of guide chip (first slope)
DESCRIPTION OF SYMBOLS 15 Optical circuit 20 and 40 Fiber array 21 Optical fiber 21a Optical fiber core 25, 45, 75 Fiber storage board 32, 62, 82 The slope (2nd slope) of a fiber storage board
34, 64, 84 V groove

Claims (6)

A guide chip mounted on an optical waveguide substrate on which an optical waveguide is formed and having a first slope extending in parallel with the optical waveguide;
A fiber storage substrate that holds an array of optical fibers and has a second slope corresponding to the first slope of the guide tip;
The fiber housing substrate includes a first portion that fits with the first inclined surface of the guide chip on the optical waveguide substrate at the second inclined surface, and the optical fiber positioned outside the optical waveguide substrate. And holding the optical fiber in a groove formed at a constant pitch in the second portion ,
The first portion covers a part of the optical waveguide extending to an end surface of the optical waveguide substrate, and in the second portion, the tip of the optical fiber is fitted to the end surface of the optical waveguide substrate, and the end surface An optical fiber connection structure , wherein an optical waveguide and the optical fiber are connected . The guide chips are a pair of guide chips disposed on both sides of the optical waveguide, and the first inclined surface is at a position facing the optical waveguide,
The optical fiber connection structure according to claim 1, wherein the second inclined surface is formed on a side surface of the fiber housing substrate. The guide chip is one guide chip disposed on the optical waveguide,
The fiber housing substrate has a recess formed in the first portion;
The optical fiber connection structure according to claim 1, wherein the second slope is formed on a side wall of the recess.   The said guide chip and the said fiber accommodation board | substrate are formed with the same material, The said 1st slope and the said 2nd slope are formed with the same crystal plane, The any one of Claims 1-3 characterized by the above-mentioned. The optical fiber connection structure described. An optical waveguide substrate having an optical circuit and an optical waveguide extending from the optical circuit;
The optical fiber connection structure according to any one of claims 1 to 4, which is disposed at an end of the optical waveguide substrate and connects the optical waveguide and an optical fiber.
An optical module. A guide chip having a first slope is mounted on an optical waveguide substrate on which an optical waveguide is formed so that the first slope is positioned in parallel with the optical waveguide,
Preparing a fiber storage substrate having a first portion having a second slope corresponding to the first slope and a second portion holding an optical fiber array behind the first portion;
The surface of the fiber storage substrate holding the optical fiber is directed to the optical waveguide substrate, the second inclined surface of the fiber storage substrate is slid onto the first inclined surface of the guide chip, and the tip of the optical fiber is Close to the end face of the optical waveguide,
When the tip of the optical fiber held by the second portion hits the end surface of the optical waveguide substrate, the fiber storage substrate is fixed to the optical waveguide substrate ,
The first portion covers a part of the optical waveguide extending to the end surface of the optical waveguide substrate, the second portion is fitted with the optical fiber to the end surface of the optical waveguide substrate, and the optical waveguide is An optical fiber connection method comprising connecting an optical fiber.

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