JP2015135403A - Optical path conversion structure and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical path conversion structure low in manufacturing cost and a method for manufacturing the same.SOLUTION: A method for manufacturing an optical path conversion structure includes a mirror forming step and a groove forming step individually, and, in order to install a mirror in a planar waveguide circuit in a subsequent installation step, performs mirror formation and groove formation by using wafer processing without using resin. The optical path conversion structure is formed with a mirror by using the wafer processing without using the resin to provide for a planar waveguide circuit and a mirror support.

Description

  The present invention relates to an optical path conversion structure used for optical communication and a method for manufacturing the same.

  In the optical communication field, an optical functional component is configured and integrated using a planar waveguide circuit. In order to perform optical communication using such a planar waveguide circuit, optical coupling for inputting light from the optical element to the planar waveguide circuit is required. In addition, optical coupling is required to extract part or all of the light from the planar waveguide circuit and input it to another optical element.

  An integrated module such as an integrated reception front-end module receives light output from the side surface of the planar waveguide circuit using an optical element disposed on the side surface without changing the optical path. In addition, light is input to the side surface of the planar waveguide circuit by an optical element. Examples of the optical element include laser diode (LD) and photo diode (PD). In order to reduce the size of the module, it is necessary to provide the module with an optical path changing function and to mount the optical element on the surface.

  Therefore, an integrated module using a vertical input / output structure as an optical coupling structure between a planar waveguide circuit and an optical element has been proposed (see, for example, Patent Document 1). In the vertical input / output structure of Patent Document 1, an optical path changing mirror for converting an optical path is provided in a part of a planar waveguide circuit, and light is input / output in a direction perpendicular to the light traveling direction in the planar waveguide circuit. . However, since the integrated integrated module disclosed in Patent Document 1 includes processing with a laser or the like in the mirror manufacturing process, it has been difficult to produce with high accuracy. For this reason, the integrated module of Patent Document 1 has a problem that the manufacturing cost increases.

  On the other hand, manufacturing a mirror that forms a mirror with high accuracy and high yield by forming a mirror support using resin in a planar waveguide circuit formed on a substrate and depositing metal on the mirror support. A method has been proposed (see, for example, Patent Document 2). However, since the mirror manufacturing method disclosed in Patent Document 2 uses a resin, it is inferior in heat resistance, and the mirror may be deformed depending on environmental conditions. Therefore, even if the manufacturing method of the mirror of patent document 2 is used, the problem that manufacturing cost becomes high cannot be solved.

Japanese Patent Laid-Open No. 11-153719 JP 2007-240781 A

  In order to solve the above-described problems, an object of the present invention is to provide an optical path conversion structure having a low manufacturing cost and a manufacturing method thereof.

  In order to achieve the above object, an optical path changing structure according to the present invention has a mirror structure having a mirror, a planar waveguide circuit having a groove for arranging the mirror structure, and a substrate having different configurations. Moreover, the manufacturing method of the optical path changing structure which concerns on this invention forms a mirror in a mirror structure using a wafer process and anisotropic etching.

  Specifically, in the method for manufacturing an optical path conversion structure according to the present invention, at least a part of the mirror forming layer is left and at least a part of the mirror forming layer is anisotropically etched to form a slope for providing a mirror. And a mirror forming step of forming a mirror support by forming a mirror on at least a part of the slope, and a planar waveguide circuit including an optical waveguide formed on the substrate, and A groove forming step for forming a groove in which the end face of the waveguide is disposed, and the groove formed in the groove forming step so that the mirror formed in the mirror forming step is positioned on the optical path of the light emitted from the end face. And an installation step of installing the mirror support inside the groove.

  The manufacturing method of the optical path changing structure of the present invention has a mirror forming step and a groove forming step separately, and uses a wafer process without using a resin in order to install the mirror in the planar waveguide circuit in the subsequent installation step. Thus, a mirror forming step and a groove forming step can be performed. For this reason, the manufacturing method of the optical path changing structure according to the present invention can form a mirror with high accuracy and high yield, so that the manufacturing cost can be reduced.

  In the method of manufacturing an optical path changing structure according to the present invention, in the mirror forming step, the inclined surface may be concaved by performing anisotropic etching of the mirror support while applying a voltage to the mirror forming layer.

  Specifically, an optical path conversion structure according to the present invention includes a planar waveguide circuit having a groove in an optical waveguide formed on a substrate, and an end surface of the optical waveguide disposed on a part of a wall surface of the groove. A mirror formed on at least a part of an inclined surface along the crystal plane of the mirror forming layer, and disposed in the groove so that the mirror is positioned on an optical path of light emitted from the end face With body.

  Since the optical path conversion structure according to the present invention includes a planar waveguide circuit and a mirror support, a mirror can be formed using a wafer process without using a resin. Therefore, the optical path conversion structure according to the present invention can form a mirror with high accuracy and high yield without using a resin, so that the manufacturing cost can be reduced.

  In the optical path conversion structure according to the present invention, the groove in the planar waveguide circuit is further provided with a handling unit that is integral with the mirror support, is wider than the groove, and is disposed outside the groove. The surface of the planar waveguide circuit adjacent to the open surface may be in contact with the surface of the planar waveguide circuit adjacent to the open surface.

  In the optical path conversion structure according to the present invention, the inclined surface of the mirror may be concave.

  The light emitting module of the present invention includes an optical path conversion structure according to the present invention, and a light emitting element that causes light to enter a mirror provided in the optical path conversion structure.

  The light receiving module of the present invention includes an optical path conversion structure according to the present invention and a light receiving element that receives light from a mirror provided in the optical path conversion structure.

  According to the present invention, it is possible to provide an optical path conversion structure with a low manufacturing cost and a manufacturing method thereof.

An example of the perspective view of the optical path conversion structure which concerns on 1st embodiment of this invention is shown. An example of the perspective view of the state which removed the mirror structure from the optical path changing structure which concerns on 1st embodiment of this invention is shown. An example of sectional drawing of the optical path changing structure concerning a first embodiment of the invention of this application is shown. The other example of sectional drawing of the optical path changing structure which concerns on 1st embodiment of this invention is shown. An example of the state which laminated | stacked the mask layer on the support substrate and the mirror formation layer among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of the state which etched the mask layer on a support substrate among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of the state which isolate | separated by etching the support substrate among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of the state which further etched the support substrate isolate | separated by the etching among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of the state which anisotropically etched the support substrate and the mirror formation layer among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of the state which removed the mask layer by the etching among the mirror formation processes which concern on 1st embodiment of this invention is shown. An example of sectional drawing and a top view in the state where a mirror was formed by vapor deposition of a reflective film among mirror formation processes concerning a first embodiment of the present invention is shown. An example of the schematic diagram explaining the light emitting module which is 2nd embodiment of this invention is shown. An example of the schematic diagram explaining the light reception module which is 3rd embodiment of this invention is shown.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to embodiment shown below. These embodiments are merely examples, and the present invention can be implemented in various modifications and improvements based on the knowledge of those skilled in the art. In the present specification and drawings, the same reference numerals denote the same components.

(First embodiment)
An example of a perspective view of the optical path conversion structure 10 according to the first embodiment of the present invention is shown in FIG. FIG. 2 is a perspective view showing a state in which the mirror structure 810 is removed from the optical path conversion structure 10 in FIG. The optical path conversion structure 10 according to the present embodiment includes a mirror structure 810, a substrate 11, and a planar waveguide circuit 12. In FIG. 1, the mirror structure 810 is indicated by a thick line. The mirror structure 810 includes a mirror support 810a and a handling unit 810b. The mirror support 810a and the handling part 810b have an integral structure.

  The planar waveguide circuit 12 is disposed on the substrate 11. The substrate 11 and the planar waveguide circuit 12 include a groove 18. On the wall surface of the groove 18, the end face 12 b of the optical waveguide provided in the planar waveguide circuit 12 is disposed. For example, the planar waveguide circuit 12 is formed of a lower clad disposed on the substrate 11, a core disposed on the lower clad, and an upper clad disposed on the core. When guided, the groove 18 is deeper than the core.

  A mirror support 810 a is accommodated in the groove 18. The length Lg of the groove 18 is larger than the length Lm of the mirror support 810a. Further, the width Wg of the groove is larger than the width Wm of the mirror support 810a, but it is preferable that Wg and Wm are substantially equal. The groove 18 has one end 12a of the groove 18 disposed therein. The end portion 12a includes an end surface 12b of the optical waveguide. The light guided through the planar waveguide circuit 12 is emitted from the end face 12 b and reflected by the mirror 81. The light incident on the planar waveguide circuit 12 is reflected by the mirror 81 and enters the planar waveguide circuit 12 from the end face 12b. Reference numeral 14 denotes a side parallel to an optical path of light emitted from the end surface 12b or incident on the end surface 12b among the sides constituting the groove 18.

  FIG. 3 is a cross-sectional view taken along the alternate long and short dash line indicated by A-A ′ in FIG. 1. The alternate long and short dash line shown by AA ′ in FIG. 1 is on a plane parallel to the surface where the substrate 11 and the planar waveguide circuit 12 are in contact, inside the groove 18, and parallel to the side 14 of the groove. . The A-A ′ sectional view shown in FIG. 3 is a view taken along a plane perpendicular to the plane where the substrate 11 and the planar waveguide circuit 12 are in contact, including the alternate long and short dash line indicated by A-A ′. An optical path 16 shown in FIG. 3 is an example of an optical path of light guided through the planar waveguide circuit 12. The optical path 17 is an example of an optical path of light that connects the mirror 81 and the direction of the mirror 81. Here, the direction of the mirror 81 is not limited to the direction corresponding to the optical path 16 and the optical path 17 which are directions in which light is reflected and incident on the upper side of the substrate 11 in FIG. The direction in which light is reflected and incident toward the front side or the back side may be used.

  FIG. 4 is a cross-sectional view taken along the alternate long and short dash line indicated by B-B ′ in FIG. 1. 1 is on the surface where the substrate 11 outside the groove 18 and the planar waveguide circuit 12 are in contact with each other, and is in parallel with the side 14 of the groove. The B-B ′ sectional view shown in FIG. 4 is a view taken along a plane that includes the alternate long and short dash line indicated by B-B ′ and that is perpendicular to the plane where the substrate 11 and the planar waveguide circuit 12 are in contact.

  The mirror support 810 a includes a mirror 81 and a mirror forming layer 22. The mirror 81 is formed on at least a part of the slope along the crystal plane of the mirror forming layer 22 provided in the mirror support 810a. The mirror 81 is disposed on the optical path of light guided through the planar waveguide circuit 12. The slope of the mirror forming layer 22 that forms the mirror 81 may be a concave surface. The handling unit 810 b includes a mirror forming layer 22, a connection layer 23, a support substrate 24, and a reflective film 82.

  The width Wh of the handling part 810 b is larger than the width Wg of the groove 18 and is disposed outside the groove 18. Further, a part of the handling part 810b and a part of the surface on which the mirror 81 is arranged functions as the mirror structure-side abutting part 15. In the planar waveguide circuit 12, the surface facing the end surface 12b of the groove 18 is an open surface. The planar waveguide circuit 12 includes a PLC-side abutting portion 13 on both end surfaces adjacent to the open surface, that is, the surface in contact with the side 14. The PLC-side abutting portion 13 is in contact with the mirror structure-side abutting portion 15 on the surface as shown in FIG. By providing the PLC-side butting portion 13 and the mirror structure-side butting portion 15, the mirror structure 810 can be easily arranged in the groove 18. Thereby, an increase in cost of the optical path conversion structure 10 can be suppressed.

Examples of the substrate 11 include a Si substrate and a SiO ₂ substrate. An example of the planar waveguide circuit 12 is an optical waveguide based on Planar Lightwave Circuit (PLC). In FIG. 1, only the vicinity of the mirror structure 810 is extracted and shown, and the planar waveguide circuit 12 and the substrate 11 are also connected to a portion not shown in FIG. Further, the optical path conversion structure 10 shown in FIG. 1 is not limited to the planar waveguide circuit 12 and the end portion of the substrate 11, but may be an intermediate portion.

  A method for manufacturing the mirror structure 810 according to the first embodiment will be described. The manufacturing method of the optical path changing structure 10 includes a mirror forming step, a groove forming step, and an installation step. In the mirror forming step, at least a part of the mirror forming layer 22 is left and at least a part of the mirror forming layer 22 is anisotropically etched to form a mirror support surface 65 including a slope for providing the mirror 81, and the mirror support surface In this step, a mirror structure 810 is formed by forming a mirror 81 on at least a part of 65. The groove forming step is a step of forming a groove 18 deeper than the optical waveguide in the planar waveguide circuit 12 including the optical waveguide formed on the substrate 11. In the groove forming process, the installation process is such that the mirror 81 formed in the mirror forming process is positioned on at least one surface of the mirror structure 810 on the optical path of the light emitted from the planar waveguide circuit 12. It is a step of installing inside the formed groove 18.

  First, in the mirror forming process, at least a part of the mirror forming layer 22 is left and at least a part of the mirror forming layer 22 is anisotropically etched to form a mirror support surface 65 including a slope for providing the mirror 81. The process will be described. Specifically, the process from the state of FIG. 5 to the state of FIG. 10 through the states of FIG. 6, FIG. 7, FIG. 8, and FIG. 22 is a step of forming a mirror support surface 65 composed of a slope for providing a mirror 81 by anisotropically etching at least a part of 22.

  As shown in FIG. 5, the mask layer 25 is stacked on the support substrate 24, and the mask layer 21 is stacked below the mirror formation layer 22. There is a connection layer 23 on the mirror forming layer 22 and below the support substrate 24. Here, the mirror formation layer 22, the connection layer 23, and the support substrate 24 that form the mirror structure 810 are stacked after the mirror formation step. The mask layer 21 and the mask layer 25 are layers used for forming the mirror structure 810.

An example of the mirror forming layer 22 is Si. Examples of the mask layer 21, the mask layer 25, and the connection layer 23 include an oxide film layer such as SiO ₂ . An example of the support substrate 24 is Si. As an example of a method of laminating the mask layer 21 and the mask layer 25, there is a chemical vapor deposition (CVD). The thickness of the mask layer 21 and the mask layer 25 is, for example, about 5 μm. Here, a lamination method of the support substrate 24, the connection layer 23, and the mirror formation layer 22 is not shown, but an SOI substrate formed by bonding having a similar structure may be used. In general, the SOI substrate already has a structure corresponding to the support substrate 24, the connection layer 23, and the mirror formation layer 22.

  Next, a resist 32 is laminated on the mask layer 25 shown in FIG. The shape of the resist 32 determines the shape of the mask layer 25 after etching. The shape of the mask layer 25 determines the shape of the support substrate 24 included in the mirror structure 810. Therefore, the resist 32 has a shape that can realize the shape required for the support substrate 24 included in the mirror structure 810. In the process of forming the mirror structure 810, the support substrate 24 is etched in three stages. The mask layer 25 formed using the resist 32 determines the second-stage and third-stage etched portions of the support substrate 24. An example of the resist 32 is a photoresist. A photoresist is a compound used in photolithography, whose physical properties such as solubility are changed by ultraviolet rays or the like. Photoresist is applied to the material surface to protect the material surface from subsequent processing such as etching. Next, the mask layer 25 without the resist 32 is removed by etching as shown in FIG.

  Next, the resist 32 shown in FIG. 6 is removed. Next, a resist 42 is stacked. The resist 42 determines the location of the first stage etching of the support substrate 24. The shape of the resist 42 determines the shape of the mirror formation layer 22 provided in the mirror structure 810. Therefore, the resist 42 has a shape that can realize the shape required for the mirror formation layer 22 included in the mirror structure 810. Next, the support substrate 24 without the resist 42 is etched. This etching is the first stage etching of the support substrate 24. An example of a method for etching the support substrate 24 is Inductive Coupled Plasma-Reactive Ion Etching (ICP-RIE). The thickness of the support substrate 24 is about 400 μm, for example.

  Next, the resist 42 shown in FIG. 7 is removed. Next, the support substrate 24 is etched using the mask layer 25 as a mask. The etching of the support substrate 24 is a second stage etching of the support substrate 24. In this etching, the support substrate 24 without the mask layer 25 is etched. The etching is stopped before the support substrate 24 is completely removed. After the mirror structure 810 is formed by the second-stage etching of the support substrate 24, the support substrate 24 does not block the optical path 17 of the light reflected by the mirror 81 shown in FIG.

  Next, anisotropic wet etching is performed on the support substrate 24 and the mirror formation layer 22 of FIG. This anisotropic wet etching is a third stage etching of the support substrate 24. The third stage etching of the support substrate 24 is performed to form the mirror support surface 65 and the mirror support surface 66 which are mirror support surfaces for forming the mirror 81 of the mirror structure 810. An example of an etchant used for wet etching is potassium hydroxide (KOH). In the etching using KOH, for example, an etching solution containing 40% by mass of KOH is used. The temperature at the time of etching is 80 ° C., for example. As shown in FIG. 9, the etched surfaces of the mirror forming layer 22 and the support substrate 24 are inclined with respect to the mask layer 21.

  In the etching, a voltage may be applied to the support substrate 24 and the mirror formation layer 22. An example of the voltage applied to the support substrate 24 and the mirror forming layer 22 is 6V. When a voltage is applied to the support substrate 24 and the mirror formation layer 22 during the etching, the etched support substrate 24 and the etched inclined surface of the mirror formation layer 22 can be made concave.

  The anisotropic etching will be briefly described. The single crystal of Si has a diamond structure, and Si atoms inside the crystal are each covalently bonded by four bonds. The bonding state of the surface Si atoms varies depending on the crystal plane appearing on the surface. For example, on the (100) plane of Si, two bonds out of four bonds of Si atoms are cut and connected by two bonds. However, Si atoms are connected by three bonds on the (111) plane of Si, and only one bond is broken. For this reason, the (111) plane is less likely to be etched than the (100) plane, and the etching rate is slow. As a result, when the Si single crystal is wet-etched from the (100) plane of Si, a (111) plane that is difficult to etch appears on the surface. The surface remaining after the etching is a smooth surface along the crystal plane.

  When the support substrate 24 and the mirror formation layer 22 are single crystals of Si, the mirror support surface 65, the mirror support surface 66, the inclined surface 67, and the inclined surface 68 are Si (111) surfaces. That is, the crystal planes of the support substrate 24 and the mirror formation layer 22 are exposed to be inclined with respect to the connection layer 51 and the connection layer 53 by etching. However, the orientation of the Si (111) plane is determined by the orientation of the crystal axes of the support substrate 24 and the mirror forming layer 22 which are Si single crystals. Therefore, by changing the orientation of the crystal axis when laminating the mirror forming layer 22 and the support substrate 24, the orientation of the exposed Si (111) plane can be changed. By changing the orientation of the exposed Si (111) surface, the direction in which the light incident on the mirror 81 is reflected can be selected.

  When the support substrate 24 and the mirror forming layer 22 having the Si (100) surface as a surface are etched with KOH from the upper surface, that is, from the upper side in FIG. 7, the angle α of the mirror support surface 65 shown in FIG. β, the angle γ of the mirror support surface 67, and the angle δ of the mirror support surface 68 are each about 55 degrees. In the etching for applying a voltage to the support substrate 24 and the mirror forming layer 22, the support substrate 62, the support substrate 64, the mirror support 61, and the mirror support 63 are concave, so that the mirror 81 and the mirror 83 also have a light collecting effect. Although etching using KOH has been described here, other examples of the etchant include tetramethylammonium hydroxide (TMAH) and a mixed solution of nitric acid, hydrofluoric acid, and acetic acid.

  Next, the mask layer 21, the mask layer 25, and the connection layer 23 in FIG. 9 are etched. This etching is performed to provide the mirror 81 on the mirror structure 810. As shown in FIG. 10, the mask layer 21 and the mask layer 25 are removed by etching.

  Next, a step of forming a mirror on at least a part of the slope in the mirror forming step will be described. The reflective film for forming the mirror 81 and the mirror 83 is deposited on the mirror forming layer 22 and the support substrate 24 of FIG. By the deposition of the reflective film, as shown in the cross-sectional view of FIG. 11, a mirror 81, a mirror 83, a reflective film 82, and a reflective film 84 are formed. Although not used in the step of forming a mirror on at least a part of the described slope, for example, a reflective film of metal is deposited by lift-off to form a mirror 81 and a mirror 83, and a reflective film 82 and a reflective film 84 are not formed. It can also be. Lift-off is a technique in which when a metal is deposited on a pattern made of a photoresist and the photoresist is removed later, the metal pattern remains only in a portion where there is no photoresist. Gold and aluminum are mentioned as an example of the metal used as a reflecting film.

  Next, the process of providing the handling part 810b on the mirror structure 810 will be described. From the lower side of the mirror structure 810, the mirror forming layer 22 and the connection layer 23 corresponding to the portion 85 to be removed from the lower surface shown by shading in the lower surface view of FIG. To do. The lower side of the mirror structure 810 corresponds to the back surface of the SOI wafer. Specifically, the mirror forming layer 22 is removed from the left and right ends of the mirror support surface 65 when facing the mirror support surface 65 toward the center, and the mirror formation layer 22 when facing the mirror support surface 65 is removed. The width is made smaller than the width Wg of the groove formed by the groove forming step. By removing part of the support 22, a part of the mirror structure 810 that is not housed in the groove becomes a handling portion 810 b having a width larger than the width of the groove.

  The width Wm of the mirror forming layer 22 after the etching shown in FIGS. 1 and 11 is made narrower than the width Wg of the groove. Since the support substrate 24 is not etched after the mirror formation layer 22 is etched, the width Wh of the support substrate 24 functioning as the handling portion 810b is wider than the width Wm of the mirror formation layer 22 and the width Wg of the groove. By forming the handling portion 810b, the mirror structure 810 and the mirror structure 811 are completed. Although the mirror structure 810 is described here, the mirror structure 810 and the mirror structure 811 have the same structure.

  Next, the groove forming step will be described. The groove forming step is a step of forming the groove 18 deeper than the core of the optical waveguide in the planar waveguide circuit 12 having the optical waveguide formed on the substrate 11 and further forming the PLC side abutting portion 13. A groove 18 for installing the mirror structure 810 is formed in the substrate 11 and the planar waveguide circuit 12 of FIG. The shape of the groove 18 is at least the width and depth at which the mirror structure 810 can be installed. When the mirror structure 810 is installed, the mirror 81 having the mirror structure 810 that transmits light guided through the planar waveguide circuit 12 is formed. It is necessary to have a shape that can be reflected. Therefore, the width Wg of the groove 18 is larger than the width Wm of the mirror structure 810. Comparing the sizes of Wh, Wg, and Wm, Wh is the largest, Wg is the next largest, and Wm is the smallest. Here, the formation of the groove 18 for installing the mirror structure 810 has been described, but the same applies to the case where the mirror structure 811 or another mirror structure is used.

  Next, a part of the planar waveguide circuit 12 is etched to form the PLC side abutting portion 13. Specifically, the PLC-side abutting portion 13 is formed on a surface that is a part of the planar waveguide circuit 12 outside the groove and is adjacent to the surface facing the end surface 12b of the optical waveguide of the planar waveguide circuit 12. Form. At least a part of the end portion of the groove in the direction perpendicular to the optical path 16 shown in FIG. 3 is opened to form the PLC-side abutting portion 13. Due to the formation of the PLC-side abutting portion 13, the mirror forming layer 22 that functions as a part of the handling portion 810 b is installed on the substrate 11 after an installation step described later.

  Next, the installation process will be described. In the installation process, the mirror structure 810 is installed inside the groove formed in the groove formation process so that the mirror 81 formed in the mirror formation process is positioned on the optical path of the light emitted from the planar waveguide circuit 12. It is a process. Specifically, the mirror structure 810 is installed in a groove provided in the substrate 11 and the planar waveguide circuit 12 as shown in FIG. Further, the mirror structure 810 brings the mirror structure-side abutting portion 15 of the mirror structure 810 into contact with the PLC-side abutting portion 13 as shown in FIGS. Since the mirror structure 810 can be installed by passive alignment in which the PLC-side butting portion 13 and the mirror structure-side butting portion 15 are brought into contact with each other, the mirror structure 810 can be easily arranged in the groove 18.

  When the mirror structure 810 needs to be fixed, for example, the handling portion 810b of the mirror structure 810 is fixed to the planar waveguide circuit 12 using an ultraviolet curable resin. When the mirror structure 810 is installed in a groove provided in the substrate 11 and the planar waveguide circuit 12 as shown in FIG. 3, the mirror 81 provided in the mirror structure 810 functions as the mirror 81 in FIGS. To do. The optical path conversion structure and the like shown in FIG. 1 show only the vicinity of the optical path conversion structure, and the optical waveguide and the like are connected to a portion not shown in FIG. Here, the formation of the groove for installing the mirror structure 810 has been described, but the same applies to the case where the mirror structure 811 or another mirror structure is used.

(Second embodiment)
FIG. 12 shows a light emitting module according to the second embodiment of the present invention. The light emitting module according to the present embodiment includes an optical path conversion structure 10, a light emitting element 91, and an optical element fixing substrate 93. Reference numeral 911 denotes an optical path until the light output from the light emitting element 91 is reflected by the mirror 81, and 912 denotes an optical path after the light output from the light emitting element 91 is reflected by the mirror 81. Reference numeral 92 denotes a reflecting surface for guiding the output light of the light emitting element 91 to the optical path 911 when the light emitting element 91 is an end face light emitting element such as an LD (Laser Diode). That is, when the light emitting element 91 is a surface light emitting element, the light emitting surface is above the mirror 81, and the light emitted from the light emitting element 91 passes through the optical path 911 and the optical path 912, the reflecting surface 92 is unnecessary.

  The light output from the light emitting element 91 is reflected by the mirror 81, undergoes optical path conversion, and is input to the planar waveguide circuit 12. When the light emitting element 91 has the reflecting surface 18, the reflecting surface 92 is inserted in the optical path between the light emitting element 91 and the planar waveguide circuit 12.

(Third embodiment)
FIG. 13 shows an example of a light receiving module according to the third embodiment of the present invention. The light receiving module according to the present embodiment includes an optical path conversion structure 10 and a light receiving element 101. In the present embodiment, the light emitting element 91 provided in the first embodiment is replaced with the light receiving element 101, and the optical element fixing substrate 93 and the reflecting surface 92 provided in the first embodiment for using the light emitting element 91 are provided. Omitted. The optical paths of light received by the light receiving element are 1011 and 1012. Reference numeral 1011 denotes an optical path after the light received by the light receiving element 101 is reflected by the mirror 81, and 1012 denotes an optical path before the light received by the light receiving element 101 is reflected by the mirror 81. The light guided through the planar waveguide circuit 12 is reflected by the mirror 81 to change the optical path, and is input to the light receiving element 101.

  The optical path changing structure and the method for producing the same according to the present invention can be applied to the communication industry.

10: Optical path conversion structure 11: Substrate 12: Planar waveguide circuit 12a: End part 12b: End face 13: PLC side abutting part 14: Groove side 15: Mirror structure side abutting part 16: Optical path 17: Optical path 18: Groove 21: Mask layer 22: Mirror forming layer 23: Connection layer 24: Support substrate 25: Mask layer 32: Resist 42: Resist 65: Mirror support surface 66: Mirror support surface 67: Slope 68: Slope 81: Mirror 82: Reflection Film 83: Mirror 84: Reflective film 85: Part to be removed from the lower surface 810: Mirror structure 810a: Mirror support 810b: Handling part 811: Mirror structure 91: Light emitting element 92: Reflecting surface 93: Optical element fixed substrate 911 Optical path 912: Optical path 101: Light receiving element 1011: Optical path 1012: Optical path

Claims (7)

Mirror support is provided by forming an inclined surface for providing a mirror by anisotropically etching at least a part of the mirror forming layer while leaving at least a part of the mirror forming layer, and forming a mirror on at least a part of the inclined surface. A mirror forming step for forming a body;
A groove forming step of forming, in a planar waveguide circuit including an optical waveguide formed on a substrate, a groove in which an end surface of the optical waveguide is disposed on a part of a wall surface;
An installation step of installing the mirror support in the groove formed in the groove formation step so that the mirror formed in the mirror formation step is positioned on the optical path of the light emitted from the end face;
The manufacturing method of the optical path changing structure which has this. In the mirror forming step, the inclined surface is made concave by performing anisotropic etching of the mirror support while applying a voltage to the mirror forming layer.
The manufacturing method of the optical path conversion structure of Claim 1. A planar waveguide circuit having a groove in an optical waveguide formed on a substrate, and an end face of the optical waveguide disposed on a part of a wall surface of the groove;
A mirror support having a mirror formed on at least a part of a slope along the crystal plane of the mirror forming layer and disposed in the groove so that the mirror is positioned on an optical path of light emitted from the end face When,
An optical path changing structure. The mirror support is integral with the width of the groove, and further includes a handling portion disposed outside the groove,
The surface facing the end surface of the groove in the planar waveguide circuit is an open surface,
Both ends of the planar waveguide circuit adjacent to the handling part and the open surface are in contact with each other at the surface,
The light conversion structure according to claim 3. The optical path changing structure according to claim 3 or 4, wherein the inclined surface of the mirror is a concave surface. An optical path changing structure according to any one of claims 3 to 5,
A light emitting element that makes light incident on the mirror;
A light emitting module comprising: An optical path changing structure according to any one of claims 3 to 5,
A light receiving element that receives light from the mirror;
A light receiving module comprising:

Images