JP2016133583A - Optical circuit and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical circuit capable of downsizing and a method for manufacturing the same.SOLUTION: An optical circuit 30 includes: input-output waveguides 11 and 12; a waveguide 13 for inspection; a slab waveguide 14; and an array waveguide 15. The waveguide 13 for inspection is connected with the slab waveguide 14 with which the input-output waveguide 12 is connected. The waveguide 13 for inspection includes an inspection port 13a on a second end surface 31b opposing a first end surface 31a. The waveguide 13 for inspection is interrupted at a second end point 13b and a first end point 13c located on a third end surface 31c.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an optical circuit and a manufacturing method thereof.

  Currently, studies for the purpose of downsizing an optical module used in an optical communication system and reducing the number of parts are continuing. For example, as in Patent Document 1, a method of achieving miniaturization of an optical module by arranging input / output ports of an input / output waveguide of an optical circuit on the same end surface of a substrate is conceivable. However, when the optical circuit is manufactured, if the input / output ports of the waveguide of the optical circuit are collectively arranged on one end face of the substrate, the input waveguide and the output waveguide are arranged close to each other. Therefore, there is a problem that it is difficult to inspect the optical circuit.

  Therefore, a configuration like the optical circuit 10 shown in FIG. 1 is used. The optical circuit 10 includes an input / output waveguide 11, an input / output waveguide 12, an inspection waveguide 13, a slab waveguide 14, and an arrayed waveguide 15. The inspection waveguide 13 has an inspection port 13a. Reference numeral 16b denotes a separation line. The inspection port 13 a of the inspection waveguide 13 is routed so as to face the input / output port of the input / output waveguide 11 or the input / output waveguide 12. W10 is the width of the optical circuit 10, and W10 is the distance between the separation lines 16b that sandwich the optical circuit 10.

  FIG. 2 shows an example in which four optical circuits 10 are arranged on the upper surface of the wafer. In the optical circuit 10, an input / output waveguide 11 that functions as an input waveguide and an input / output waveguide 12 that functions as an output waveguide are arranged close to each other. However, since the inspection waveguide 13 and the inspection port 13a for inspection are provided on the opposite sides of the input / output ports of the input / output waveguide 11 and the input / output waveguide 12, the inspection jig and the inspection instrument can be used as bars, It can be installed facing the chip. Therefore, inspection is easy.

  When the number of channels of the optical circuit is small, the optical circuit 10 can be arranged in parallel in the same direction as shown in FIG. Here, the number of channels is the sum of the number of waveguides included in the input / output waveguide 11 and the input / output waveguide 12. In addition, the inspection waveguide 13 is curved on the input / output waveguide 12 side, and the inspection waveguide 13 is guided to the end opposite to the input / output waveguide 11 and the input / output waveguide 12, thereby making the optical circuit 10. The chip is reduced in size.

  The interval between the waveguides of the input / output waveguide 11 and the input / output waveguide 12 is 127 μm, for example. Therefore, the length in the x direction in which the input / output waveguides of the optical circuit 10 are arranged is at least 127 μm and the number of channels. Therefore, when the number of channels is small, the optical circuit 10 will not be increased in size by extending the x direction unless the routing area of the inspection waveguide 13 or the like is widened. However, the length of the optical circuit 10 in the y direction is substantially constant regardless of the number of channels. This is because the radius of curvature of the waveguide of the optical circuit 10 cannot be reduced.

  At present, however, there is an increasing demand for miniaturization of an optical module having multiple channels, and further miniaturization of an optical circuit having a high Δ waveguide structure is demanded. Here, Δ is a relative refractive index difference between the core and the clad constituting the waveguide. Since the curvature radius of the waveguide can be designed to be small by increasing Δ, the slab waveguide 14 and the arrayed waveguide 15 in the optical circuit 10 can be reduced in size by increasing the density of arranging the waveguides. However, since it is difficult to secure a space for disposing the inspection waveguide 13, there is a problem that it is difficult to reduce the size of the optical circuit 10 as a whole.

  In the high Δ optical circuit 20 having a large number of channels as shown in FIG. 3, there is no empty space near the input / output ports of the input / output waveguide 11 and the input / output waveguide 12 due to the large number of channels. Therefore, the inspection waveguide 13 is curved from the slab waveguide 14 to the opposite side to the input / output waveguide 12 and continues to the end surface facing the end surface to which the input / output port of the input / output waveguide 12 is connected.

  In the configuration like the optical circuit 20, the number of channels is large, so that the x-axis direction is long, but the y-axis direction can be shortened by the amount of high Δ. Since the minimum distance between the input / output waveguide 11 and the input / output waveguide 12 does not change even when the Δ is increased, the x direction of the chip size of the optical circuit 20 is limited to the product of the minimum distance between the waveguide and the number of channels. .

  Thus, although the length in the y direction of the optical circuit 20 can be reduced by increasing Δ, the length in the x direction is mainly determined by the number of channels, so it is not easy to reduce the length in the x direction of the optical circuit 20. There was no problem. Further, the inspection waveguide 13 becomes unnecessary after the inspection is completed, but the necessity of providing the inspection waveguide 13 is also a barrier to downsizing.

Japanese Patent Laid-Open No. 2004-4907

  In order to solve the above-described problems, the present invention realizes the miniaturization of an optical circuit having an arrayed waveguide by using a blank area of an adjacent optical circuit for arranging a testing waveguide and a testing port. Objective.

  In order to achieve the above object, an optical circuit according to the present invention is an optical circuit in which an inspection waveguide that is unnecessary after inspection of an optical circuit is provided in a blank area of an adjacent optical circuit. The method for manufacturing an optical circuit according to the present invention is a method for manufacturing the optical circuit according to the present invention.

  Specifically, an optical circuit according to the present invention is for testing an optical waveguide circuit in which a plurality of input / output ports are arranged on a first end face, and the optical waveguide circuit connected to the optical waveguide circuit. And an inspection waveguide, wherein the inspection waveguide is interrupted at a first end point located on a third end surface substantially perpendicular to the first end surface.

  In the optical circuit according to the present invention, the inspection waveguide is interrupted between the optical waveguide circuit and the inspection port. This is because the inspection waveguide connected to the inspection port at the time of manufacturing the optical circuit is formed so as to cross the boundary with the adjacent optical circuit. As described above, in the optical circuit according to the present invention, the inspection port and the inspection waveguide connected to the inspection port are arranged in the blank area of the adjacent optical circuit when the optical circuit is manufactured. Miniaturization can be realized.

  In the optical circuit according to the present invention, a waveguide guided from a second end point different from the first end point of the third end surface to a second end surface opposed to the first end surface is further provided. You may have.

  The optical circuit according to the present invention may further include a waveguide connecting the third end point and the fourth end point of the third end face.

  The optical circuit according to the present invention may further include a waveguide that connects the third end point and the fourth end point of the fourth end face facing the third end face.

  The optical circuit according to the present invention may further include a waveguide guided from the third end point of the fourth end surface facing the third end surface to the first end surface.

  The optical circuit according to the present invention may further include a waveguide guided to the first end surface from a second end point different from the first end point of the third end surface.

  Specifically, an optical circuit manufacturing method according to the present invention includes: an optical waveguide circuit connected to a plurality of input / output ports; and a plurality of optical circuits including a test waveguide connected to the optical waveguide circuit on a wafer. An optical circuit forming method comprising: an optical circuit forming step formed in a step; and a separation step separated at a boundary between the plurality of optical circuits, wherein in the optical circuit forming step, The second input / output port of the first optical circuit is disposed on the first end face, and the input / output port of the second optical circuit of the two optical circuits faces the first end face. The optical waveguide circuit is formed so as to be disposed on an end face, and an inspection port connected to the inspection waveguide of the second optical circuit and an inspection port connected to the inspection waveguide of the first optical circuit Arranged on opposite surfaces, and the first optical circuit and As at least one of the inspection waveguide of said second optical circuit crosses at least one said boundary to form the test waveguide.

  Since the method for manufacturing an optical circuit according to the present invention includes an optical circuit formation step and a separation step, a plurality of optical circuits can be simultaneously manufactured on one wafer and then separated for each optical circuit. Here, in the optical circuit forming process, the inspection waveguide connected to the inspection port of the optical circuit is formed so as to cross the boundary of the adjacent optical circuit. Therefore, the inspection port of the optical circuit and the inspection waveguide are formed in the adjacent optical circuit. It can be placed in the margin area. Therefore, the method for manufacturing an optical circuit according to the present invention can realize downsizing of an optical circuit having an arrayed waveguide.

  In the method for manufacturing an optical circuit according to the present invention, the two adjacent optical circuits are arranged so as to have a point-symmetric or line-symmetric relationship.

  In the method for manufacturing an optical circuit according to the present invention, an optical circuit having a line symmetry relationship with the first optical circuit may be formed as the second optical circuit with respect to one side of the first end face.

  The above inventions can be combined as much as possible.

  According to the present invention, it is possible to provide a method for manufacturing a miniaturized optical circuit and an optical circuit manufactured by the manufacturing method.

An example of a conventional optical circuit is shown. An example in which four conventional optical circuits with a small number of channels are arranged is shown. An example in which four conventional optical circuits with a large number of channels are arranged will be shown. 1 shows an example of an optical circuit 30 according to a first embodiment of the present invention. An example is shown in which four optical circuits 30 according to the first embodiment of the present invention are arranged so that adjacent optical circuits 30 constituting a set are point-symmetric with respect to the center of the boundary line 16a. It is a modification of the first embodiment of the present invention, and is an example in which four optical circuits 30 are arranged so that adjacent optical circuits 30 constituting a set are point-symmetric with respect to the center of the boundary line 16a. Indicates. An example of the optical circuit 50 which concerns on the 2nd Embodiment of this invention is shown. An example in which four optical circuits 50 according to the second embodiment of the present invention are arranged will be shown. An example of the optical circuit 55 which concerns on another form of the 2nd Embodiment of this invention is shown. An example in which four optical circuits 55 according to another form of the second embodiment of the present invention are arranged will be shown. An example of the optical circuit 60 which concerns on the 3rd Embodiment of this invention is shown. An example is shown in which four optical circuits 60 according to the third embodiment of the present invention are arranged so that adjacent optical circuits 60 constituting a set are point-symmetric with respect to the center of the boundary line 16a. The optical circuits 60 according to the third embodiment of the present invention are arranged so that the adjacent optical circuits 60 constituting the set are point-symmetric with respect to the center of the boundary line 16a, and the set adjacent to the set is the boundary line. An example in which four lines are arranged so as to be line symmetric with respect to 16a 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)
FIG. 4 shows an example of the pattern of the optical circuit 30 formed on the wafer according to the first embodiment of the present invention. The optical circuit 30 includes an input / output waveguide 11, an input / output waveguide 12, an inspection waveguide 13, a slab waveguide 14, and an arrayed waveguide 15. The input / output waveguide 11 and the input / output waveguide 12 include an input / output port on the first end face 31a. In this embodiment, the input / output waveguide 11, the input / output waveguide 12, the slab waveguide 14, and the arrayed waveguide 15 function as an optical waveguide circuit.

  In the optical waveguide circuit of this embodiment, two slab waveguides 14 are connected by an arrayed waveguide 15, one slab waveguide 14 is connected to the input / output waveguide 11, and the other slab waveguide 14 is input / output guided. Connected to the waveguide 12. The input / output ports of the input / output waveguide 11 and the input / output waveguide 12 are arranged on the first end face 31a. An end face having input / output ports of the input / output waveguide 11 and the input / output waveguide 12 is an end face 31a, and an end face facing the end face 31a is an end face 31b. Since each of the input / output waveguide 11 and the input / output waveguide 12 has one or more waveguides, a plurality of input / output ports are arranged on the first end face 31a. The plurality of input / output ports are, for example, 15 or more and 60 or less input / output ports. Each of the input / output waveguide 11 and the input / output waveguide 12 is disposed in a region sandwiched between the boundary line 16a and the separation line 16b. When two optical circuits 30 constituting a set are formed on both sides of the boundary line 16a and the optical circuits are separated by the boundary line 16a, a third end face 31c is formed. Further, when the optical circuit formed in units with the separation line 16b interposed therebetween is separated by the separation line 16b, a fourth end face 31d is formed.

  The inspection waveguide 13 for inspecting the optical waveguide circuit is connected to the slab waveguide 14 to which the input / output waveguide 12 is connected. The inspection waveguide 13 has an inspection port 13a on the second end surface 31b facing the first end surface 31a. The inspection waveguide 13 is interrupted at the second end point 13b and the first end point 13c located on the third end face 31c. Therefore, the inspection waveguide 13 includes a waveguide connecting the inspection port 13a and the second end point 13b, and a waveguide connecting the first end point 13c and the slab waveguide 14.

  Here, the third end face 31c is an end face separated from another optical circuit 30 adjacent on the wafer when the optical circuit 30 is manufactured, and is in contact with the first end face 31a and the second end face 31b. At the same time, it is substantially perpendicular to the first end surface 31a and the second end surface 31b. W30 is the width of the optical circuit 30, and is the distance between the boundary line 16a and the separation line 16b separated from the wafer when the optical circuit 30 is manufactured.

  The optical circuit 30 according to the present embodiment includes the waveguide 17. The waveguide 17 outputs light input from the third end point 17a of the third end face 31c from the fourth end point 17b of the third end face 31c, and input from the fourth end point 17b of the third end face 31c. The emitted light is output from the third end point 17a of the third end face 31c. In the optical circuit 30 according to the present embodiment, the second end point 13b, the first end point 13c, the third end point 17a, and the fourth end point 17b are disposed on the same third end face 31c.

  Next, a method for manufacturing the optical circuit 30 according to the present embodiment will be described. The manufacturing method of the optical circuit 30 according to the present embodiment includes an optical circuit formation step and a separation step in order. Between the optical circuit formation step and the separation step, an inspection step for inspecting the optical circuit formed in the optical circuit formation step may be included.

  In the optical circuit forming process of this embodiment, a plurality of optical circuits 30 are formed adjacent to each other on the wafer. FIG. 5 shows an enlarged view of a part of an example of the wafer on which the optical circuit 30 is formed. A plurality of optical circuits 30AB each having two optical circuits 30 as a set are arranged on the wafer. FIG. 5 shows how two sets of optical circuits AB are formed in the x direction. The optical circuit 30AB is formed on the wafer by being connected in the x and y directions, and the number of connections in the x and y directions is arbitrary.

  In an optical circuit 30AB composed of two optical circuits 30, a first optical circuit 30A and a second optical circuit 30B are adjacent to each other across a boundary line 16a. The first optical circuit 30A of one optical circuit 30AB of the two sets of optical circuits 30AB and the second optical circuit 30B of the other optical circuit 30AB are adjacent to each other with the separation line 16b interposed therebetween. Among the optical circuits 30AB, the first optical circuit 30A and the second optical circuit 30B are separated by a boundary line 16a which is a boundary between them, and one optical circuit 30AB and the other optical circuit 30AB are separated. They are separated by a separation line 16b. Here, the boundary line 16a and the separation line 16b, which are boundaries between the plurality of optical circuits 30AB, are lines that pass through a plane substantially perpendicular to the first end surface 31a and the second end surface 31b. The two inspection waveguides 13 of the optical circuit 30A and the optical circuit 30B constituting the optical circuit 30AB cross only one boundary line 16a in the optical circuit 30AB.

  In this embodiment, the optical circuit 30A of the pattern A and the optical circuit 30B of the pattern B in which the optical circuits 30A of the pattern A are arranged symmetrically are formed alternately. Specifically, input / output ports of the input / output waveguides 11 and 12 of the optical circuit 30A are arranged on the first end face 31a of the optical circuit 30A, and input / output of the input / output waveguides 11 and 12 of the optical circuit 30B. The optical waveguide circuit is formed so that the port is disposed on the first end face 31a of the optical circuit 30B. The first end face 31a of the optical circuit 30A and the second end face 31b of the optical circuit 30B are formed on the same plane. The second end face 31b of the optical circuit 30A and the first end face 31a of the optical circuit 30B are formed on the same plane.

  Each inspection port 13a of the optical circuit 30A and the optical circuit 30B of the optical circuit 30AB constituting the set is formed on the opposing surface. For example, the inspection port 13a of the optical circuit 30A is disposed on the second end face 31b of the optical circuit 30A, and the inspection port 13a of the optical circuit 30B is disposed on the second end face 31b of the optical circuit 30B. A working waveguide 13 is formed.

  The inspection port 13a of the optical circuit 30A is disposed closer to the boundary line 16a than the input / output ports of the input / output waveguides 11 and 12 of the optical circuit 30A, and the inspection port 13a of the optical circuit 30B is connected to the input / output waveguide of the optical circuit 30B. The input / output ports of the waveguides 11 and 12 are arranged on the boundary line 16a side. By adopting such an arrangement, the waveguide interval of the optical circuit 30 is 127 μm, and the total number of channels of the waveguides constituting the input / output waveguide 11 and the input / output waveguide 12 of the optical circuit 30 is 40. In some cases, of the width of the optical circuit 30 in the x direction, the width of the input / output ports of the input / output waveguides 11 and 12 is about 5 mm.

  By bringing the inspection port 13a closer to the boundary line 16a and simultaneously bringing the input / output ports of the input / output waveguides 11 and 12 closer to the boundary line 16a, the width of the optical circuit 30 in the x direction can be reduced. It can be close to the output port width of about 5 mm. In this case, in order to avoid light interference during inspection, the inspection port 13a and the input / output port of the input / output waveguide 12 are not arranged in parallel. When the input / output ports (11 and 12) and the inspection port 13a of the input / output waveguide are formed in this way, the optical circuit 30AB can form about 30 optical circuits 30 on the diameter of a 6-inch wafer.

  As shown in FIG. 5, in this embodiment, the inspection waveguide 13 is formed so that the inspection waveguide 13 connected to the inspection port 13a of the optical circuit 30A and the optical circuit 30B crosses the boundary line 16a. Specifically, the inspection waveguide 13 of the optical circuit 30A is formed to enter the optical circuit 30B from the optical circuit 30A across the boundary line 16a, and to enter the optical circuit 30A from the optical circuit 30B across the boundary line 16a. To do. The inspection waveguide 13 of the optical circuit 30B is formed so as to cross the boundary line 16a and enter the optical circuit 30A from the optical circuit 30B, and cross the boundary line 16a to enter the optical circuit 30B from the optical circuit 30A. At this time, a part of the inspection waveguide 13 is formed in a blank area where the waveguide is not arranged in the area of the adjacent optical circuit 30. As a result, the waveguide 17 shown in FIG. 4 is formed in the optical circuit 30B, and the waveguide 17 shown in FIG. 4 is formed in the optical circuit 30A.

  In the conventional optical circuit, the input / output ports connected to the input / output waveguides of the optical circuit are arranged on the same end face in order to reduce the size of the optical module and reduce the number of components. When the number of input / output ports is large, the area occupied by the inspection port 13a is separately required because the exclusive area of the input / output waveguide is increased in the conventional optical circuit. Therefore, downsizing has been difficult. Therefore, in the present embodiment, a blank area without a waveguide among areas of the adjacent optical circuit 30 is used as an area in which the inspection waveguide 13 is disposed.

  As described above, in the optical circuit forming process of the present embodiment, a part of the inspection waveguide 13 is formed in the blank area of the adjacent optical circuit 30, so that a region for routing the inspection waveguide 13 is newly provided. The area per one optical circuit 30 can be reduced by the amount of the region. Here, 18 in FIG. 5 is the position of the separation line in the conventional layout. Since the optical circuit 30 is arranged as shown in FIG. 5, the size of the optical circuit 30 can be reduced by Wdif in the x direction. Here, Wdif is the distance between the position of the boundary line 16a in the optical circuit 30 and the position of the separation line 18 arranged in the conventional layout.

  Next, the inspection process will be described. In the inspection process, the wafer on which the optical circuit 30 is formed is separated so that the input / output waveguides 11 and 12 of the optical circuit 30 and the input / output ports of the input / output waveguide 12 and the inspection port 13a are exposed at the end face, and the optical circuit 30AB is connected. After the bars are formed, each optical circuit 30 is inspected. The number of optical circuits 30 included in one bar is arbitrary. When two sets of optical circuits 30AB are included in one bar, for example, the arrangement is as shown in FIG. The optical circuit 30 is separated by, for example, cutting the wafer with a dicing saw or the like, or cleaving the wafer.

  When the wafer on which the optical circuit 30 is formed is used as a bar, for example, the wafer on which the optical circuit 30 is formed is separated at the boundary in the y direction of the optical circuit 30, and the first end surface 31a and the second end surface 31b are separated. Form. When the wafer on which the optical circuit 30 is formed is separated at the boundary in the y direction, and the first end surface 31a and the second end surface 31b are formed on the same plane, a plurality of optical circuits 30 connected in the x direction. It becomes.

  Next, the operation | movement as an optical circuit of each optical circuit 30 is test | inspected among the bars containing the some optical circuit 30. FIG. The inspection method is arbitrary. For example, an optical signal is input from the input / output port of the input / output waveguide 11, and the optical signal output to the inspection port 13 a of the inspection waveguide 13 is measured. The quality of the operating characteristics of the optical circuit 30 can be determined from the optical signal output to the inspection port 13a.

  Next, the separation process will be described. In the separation step, the plurality of optical circuits 30 are separated at the boundaries of the optical circuits 30 to form chips. For example, the wafer including the plurality of optical circuits 30 formed in the optical circuit forming process is separated at the boundary in the y direction of each optical circuit 30, and further separated by the boundary line 16a and the separation line 16b. However, in the case where the present embodiment includes an inspection process, after the inspection process is completed, the bar including the plurality of optical circuits 30 is separated by the boundary line 16a and the separation line 16b that are the boundaries of the respective optical circuits 30.

  In the present embodiment, since a part of the inspection waveguide 13 is disposed in a blank area where the waveguide is not disposed in the region of the adjacent optical circuit 30, the inspection waveguide 13 is separated when the optical circuit 30 is separated. Are also separated. Although the inspection waveguide 13 is separated, since the separation process is a subsequent process of the inspection process, no problem occurs even when the method for manufacturing the optical circuit 30 according to the present embodiment includes the inspection process.

  FIG. 5 shows an example in which even-numbered optical circuits 30 are formed on the wafer by combining two optical circuits 30 in the optical circuit forming step, but the present invention is not limited to this. For example, the number of optical circuits 30 formed simultaneously on the wafer is arbitrary and may be an odd number. When the odd-numbered optical circuits 30 are formed on the wafer, one optical circuit 30 does not constitute a pair of optical circuits 30AB.

FIG. 6 shows a modification when the optical circuit 30 according to the present embodiment is formed. In FIG. 6, the optical circuits 30D, 30B, 30A and 30C are formed adjacent to each other. The optical circuit 30D constitutes a part of an optical circuit 30CD that is a set of a plurality of optical circuits, the optical circuits 30A and 30B constitute an optical circuit 30AB that is a set of a plurality of optical circuits, and the optical circuit 30C includes a plurality of optical circuits. It constitutes a part of the optical circuit 30CD which is a set of circuits. The optical circuit 30A and the optical circuit 30C, and the optical circuit 30B and the optical circuit 30D are in a line-symmetric relationship with respect to the separation line 16b. Further, the optical circuit 30A and the optical circuit 30B, and the optical circuit 30C and the optical circuit 30D have a point-symmetric relationship with respect to the center of the boundary line 16a. The optical circuit 30A and the optical circuit 30B that form a set, and the optical circuit 30C and the optical circuit 30D that form a set are alternately arranged. Therefore, by forming the inspection waveguide 13 of the adjacent optical circuit 30 in a blank area without the waveguide, the width W30 of the optical circuit 30 can be reduced also in the modification of the present embodiment. Specifically, also in the modification of the present embodiment, the optical circuit 30 can be made smaller than the optical circuit 10 or the optical circuit 20 by Wdif shown in FIG.

(Second Embodiment)
FIG. 7 shows an example of a pattern of the optical circuit 50 formed on the wafer according to the second embodiment of the present invention. The optical circuit 50 includes an input / output waveguide 11, an input / output waveguide 12, an inspection waveguide 13, a slab waveguide 14, and an arrayed waveguide 15. The inspection waveguide 13 includes an inspection port 13a. The pair of optical circuits 50 constitute a set of optical circuits.

  In the optical circuit 30 according to the first embodiment, the second end point 13b, the first end point 13c, the third end point 17a, and the fourth end point 17b are arranged on the same third end face 31c (FIG. 4). . However, in the present embodiment, the second end point 13b and the first end point 13c are disposed on the third end surface 31c, and the third end point 17a and the fourth end point 17b are disposed on the fourth end surface 31d. Here, the fourth end surface 31d is a cross section formed by separating the optical circuit sets by the separation line 16b, and faces the third end surface 31c, and is formed on the first end surface 31a and the second end surface 31b. The surface is in contact with and substantially perpendicular to the first end surface 31a and the second end surface 31b. The waveguide 17 outputs light input from the third end point 17a of the fourth end face 31d from the fourth end point 17b of the fourth end face 31d, and inputs from the fourth end point 17b of the fourth end face 31d. The emitted light is output from the third end point 17a of the fourth end face 31d.

  Next, a method for manufacturing the optical circuit 50 according to the second embodiment will be described. The method for manufacturing the optical circuit 50 according to the present embodiment includes an optical circuit formation step and a separation step in order. Between the optical circuit formation step and the separation step, an inspection step for inspecting the optical circuit formed in the optical circuit formation step may be included. The inspection process and the separation process according to the present embodiment are the same as the inspection process and the separation process according to the first embodiment.

  In the optical circuit formation process of the present embodiment, the optical circuits 50 that are line-symmetric with respect to the x axis are formed adjacent to both sides of the boundary line 16a and the separation line 16b. Therefore, the input / output waveguides of the optical circuit 50 are formed on the opposite end faces.

  FIG. 8 shows an enlarged view of a part of an example of a wafer on which the optical circuit 50 is formed. FIG. 8 shows an example in which two sets of optical circuits 50AB each having two optical circuits 50 are formed in the x direction in a partial region on the wafer. In the optical circuit forming step, the optical circuit 50AB shown in FIG. 8 is formed by being connected in the x direction and the y direction. The number of connections in the x and y directions of the optical circuit 50AB is arbitrary.

  An optical circuit 50AB composed of the first optical circuit 50A and the second optical circuit 50B constitutes one set, and one set of the first optical circuit 50A and the other set of two adjacent optical circuits 50AB. The second optical circuit 50B is adjacent. The first optical circuit 50A and the second optical circuit 50B constituting the optical circuit 50AB are separated by a boundary line 16a which is a boundary between them in the separation step. The first end face 31a of the optical circuit 50A and the second end face 31b of the optical circuit 50B are formed on the same plane. The second end face 31b of the optical circuit 50A and the first end face 31a of the optical circuit 50B are formed on the same plane.

  The optical circuit forming process according to the present embodiment is basically the same as the optical circuit forming process according to the first embodiment. However, in the optical circuit forming process according to the present embodiment, the inspection port 13a of the first optical circuit 50A can be formed closer to the boundary line 16a than the optical circuit according to the first embodiment.

Specifically, in the arrangement of the optical circuit 30 according to the first embodiment, the curved portion (waveguide 17) of the inspection waveguide 13 of the adjacent optical circuit brings the inspection port 13a close to the boundary line 16a. It is an obstacle to formation. Therefore, the inspection waveguide 13 from the second end point 13b to the inspection port 13a avoiding the curved portion (waveguide 17) of the inspection waveguide 13 of the adjacent optical circuit includes the slab waveguide 14 and the array waveguide. 15 so as to approach 15. On the other hand, in the optical circuit 50 according to the present embodiment, the curved portion (waveguide 17) of the adjacent inspection waveguide 13 is not arranged on the end face side that forms the inspection port 13a. It can be formed in the vicinity of the boundary line 16a. In other words, in the optical circuit 50, the inspection waveguide 13 extending from the second end point 13b to the inspection port 13a can be arranged close to and parallel to the boundary line 16a. For this reason, the optical circuit 50 according to the present embodiment has the inspection port 13a and each port of the input / output waveguides 11 and 12 markedly separated from the boundary line 16a as compared with the optical circuit 30 according to the first embodiment. The length of the optical circuit 50 in the x direction can be reduced accordingly.
Here, the vicinity is a distance at which guided light is not coupled to an adjacent waveguide, and is a distance that does not cause a problem in manufacturing. For example, a distance of about the waveguide interval between the input and output waveguides is sufficient, but the influence of light coupling is negligible until the adjacent waveguide interval is about 20 μm. In addition, since it is necessary to provide a dicing marker (a pattern in which the core is left in a straight line) for separation into individual chips, it is necessary to pass the inspection WG at a position where it does not become an obstacle, It is necessary to set a position where light does not bind to this marker. Therefore, the inspection waveguide 13 and the boundary line 16a (or the separation line 16b), the inspection waveguide 13 and the input / output waveguide 11, or the inspection waveguide 13 must be at least 20 μm apart.

  The inspection waveguide 13 connected to the inspection port 13a of the optical circuit 50A and the optical circuit 50B is formed so as to cross the boundary line 16a. The inspection waveguide 13 that crosses one boundary line 16a or one separation line 16b is only the inspection waveguide 13 extending from one optical circuit. Specifically, the inspection waveguide 13 of the optical circuit 50A enters the optical circuit 50B from the optical circuit 50A across the boundary line 16a, and enters the original optical circuit 50A from the optical circuit 50B across the same boundary line 16a. To form. The inspection waveguide 13 of the optical circuit 50B crosses the separation line 16b that is a boundary with the adjacent set, enters the adjacent set optical circuit 50A, and crosses the separation line 16b again to return to the original optical circuit 50B. Form to return.

  FIG. 9 shows an example of the pattern of the optical circuit 55 formed on the wafer according to another embodiment of the second embodiment. FIG. 10 shows an enlarged view of a part of an example of a wafer on which the optical circuit 55 is formed. This different form is different from the second embodiment as shown in FIG. 10 in which the inspection port 13a of the optical circuit 55A is on the first end face 31a of the optical circuit 55B and the inspection port 13a of the optical circuit 55B is the optical circuit 55A. This is a point on the first end face 31a. In this alternative embodiment, as shown in FIG. 10, the inspection waveguide 13 only crosses the boundary line 16a or the separation line 16b once, and the first end point is formed on the third end face 31c as shown in FIG. 13c is formed, and the third end point 17a is formed on the fourth end surface 31d, but the second end point 13b is not formed on the third end surface 31c, and the fourth end point 17b is formed on the fourth end surface 31d. Is not formed. Therefore, the optical circuit 55 includes a waveguide guided from the third end point 17a of the fourth end face 31d to the inspection port 13a of the first end face 31a.

  FIGS. 8 and 10 show an example in which even-numbered optical circuits 50 or optical circuits 55 are formed on a wafer by combining two optical circuits 50AB or 55AB in the optical circuit formation step. It is not limited. That is, the number of optical circuits 50 or optical circuits 55 formed simultaneously on the wafer is arbitrary and may be an odd number. When the odd-numbered optical circuit 50 or the optical circuit 55 is formed on the wafer, one optical circuit 50 or the optical circuit 55 does not constitute the optical circuit 50AB or the optical circuit 55AB as a group.

  As described above, in the present embodiment and another embodiment of the present embodiment, the optical circuit 50A and the optical circuit 50B or the optical circuit 55A and the optical circuit 55B constitute a set. The inspection ports 13a of the optical circuit 50A and the optical circuit 50B or the optical circuit 55A and the optical circuit 55B are formed to face each other. In the optical circuit 30 according to the first embodiment, as shown in FIG. 5, the optical circuit 30 is formed point-symmetrically with respect to the center of the boundary line 16a, but the optical circuit 50A and the optical circuit 50B or the optical circuit 55A and the optical circuit 55B are The arrangement of the optical circuits formed in each has a line-symmetric relationship with respect to the x axis. Also in this embodiment and another form of this embodiment, since a part of the inspection waveguide 13 is formed in the blank area of the adjacent optical circuit 50 or optical circuit 55, the optical circuit 50 or the optical circuit is equivalent to the blank area. The area per circuit 55 can be reduced. In addition, in the present embodiment, since the waveguide 17 does not become an obstacle in forming the inspection waveguide 13, the inspection port 13a can be formed in the vicinity of the boundary line 16a or the separation line 16b. As compared with the optical circuit according to the above, the area per one of the optical circuit 50 or the optical circuit 55 can be further reduced.

(Third embodiment)
FIG. 11 shows an example of the pattern of the optical circuit 60 formed on the wafer according to the third embodiment of the present invention. The optical circuit 60 includes an input / output waveguide 11, an input / output waveguide 12, an inspection waveguide 13, a slab waveguide 14, and an arrayed waveguide 15. The inspection waveguide 13 includes an inspection port 13a.

  In the first embodiment and the second embodiment, the inspection port 13a is arranged on the second end face 31b of the same optical circuit. However, in the optical circuit 60 according to the present embodiment, the inspection port 13a is disposed on the first end face 31a of the adjacent optical circuit. The inspection waveguide 13 crosses the boundary line 16a, and the inspection port 13a of the inspection waveguide 13 is disposed in the vicinity of the separation line 16b. When the boundary line 16a is cut, a first end point 13c, a second end point 13b, and a third end surface 31c are formed in the cross section. When the separation line 16b is cut, a fourth end face 31d is formed in the cross section. However, since the inspection waveguide 13 does not cross the separation line 16b, no end point is formed.

  The optical circuit 60A and the optical circuit 60B constituting the set have a point-symmetric relationship. In the present embodiment, the optical circuits 60 having a point-symmetrical relationship are alternately formed adjacent to each other. The inspection waveguide 13 connected to the optical circuit 60B enters the optical circuit 60A from the first end point 13c, passes through the vicinity of the second end surface 31b of the optical circuit 60A, and is guided to the vicinity of the separation line 16b. The inspection port 13a of the optical circuit 60B is formed on the first end face 31a of 60A. The inspection waveguide 13 connected to the optical circuit 60A enters the optical circuit 60B from the first end point 13c, is guided to the vicinity of the separation line 16b via the vicinity of the second end face 31b of the optical circuit 60B, The inspection port 13a of the optical circuit 60A is formed on the first end face 31a of the optical circuit 60B. The first end face 31a of the optical circuit 60A and the second end face 31b of the optical circuit 60B are formed on the same plane. The second end face 31b of the optical circuit 60A and the first end face 31a of the optical circuit 60B are formed on the same plane.

  Specifically, the inspection waveguide 13 is interrupted at the second end point 13b and the first end point 13c located on the third end face 31c. Therefore, the inspection waveguide 13 includes a waveguide connecting the second end point 13b and the inspection port 13a, and a waveguide connecting the first end point 13c and the slab waveguide 14.

  Among the inspection waveguides 13 included in the optical circuit 60, the waveguide connecting the inspection port 13a and the second end point 13b is the inspection waveguide 13 connected to the optical waveguide circuit of the adjacent optical circuit 60 forming a set. That is, when the optical circuit 60A and the optical circuit 60B are adjacent to each other, the inspection waveguide 13 connected to the optical waveguide circuit of the optical circuit 60A is also formed inside the optical circuit 60B, and the optical circuit 60B The inspection waveguide 13 connected to the wave circuit is also formed inside the optical circuit 60A. The optical circuit 30 according to the first embodiment and the optical circuit 50 according to the second embodiment include the waveguide 17, but the optical circuit 60 according to the present embodiment does not include the waveguide 17.

  A method for manufacturing the optical circuit 60 according to the present embodiment will be described. The method for manufacturing the optical circuit 60 according to the present embodiment includes an optical circuit formation step and a separation step in order. Between the optical circuit formation step and the separation step, an inspection step for inspecting the optical circuit formed in the optical circuit formation step may be included. The inspection process according to the present embodiment is the same as the inspection process according to the first embodiment.

  In the optical circuit formation process of the present embodiment, a plurality of optical circuits 60 are formed adjacent to each other on the wafer. In the present embodiment, the optical circuit 60A of pattern A and the optical circuit 60B of pattern B in which the optical circuit 60A of pattern A is arranged point-symmetrically are alternately formed. The inspection waveguide 13 is formed as a waveguide continuous with the optical circuit 60A and the optical circuit 60B.

  FIG. 12 shows an enlarged view of a part of an example of the wafer on which the optical circuit 60 is formed. FIG. 12 shows a state in which two sets of optical circuits 60AB each having two optical circuits 60 are formed in the x direction in a partial region on the wafer. In the optical circuit formation step, the optical circuit 60AB shown in FIG. 12 is formed by being connected in the x direction and the y direction. The number of connections in the x and y directions of the optical circuit 60AB is arbitrary.

  In each of the two sets of optical circuits 60AB, the first optical circuit 60A and the second optical circuit 60B are adjacent to each other. Also, the first optical circuit 60A constituting one set of optical circuits 60AB and the second optical circuit 60B constituting the other set of optical circuits 60AB are adjacent to each other. The first optical circuit 60A and the second optical circuit 60B constituting the optical circuit 60AB are separated by a boundary line 16a which is a boundary between them in the separation step. The boundary line 16a that is a boundary is a line that passes through a surface substantially perpendicular to the first end surface 31a and the second end surface 31b. In one set of optical circuits 60AB, the two inspection waveguides 13 of the optical circuit 60A and the optical circuit 60B constituting the set cross one boundary line 16a.

  The optical circuit formation process according to the present embodiment is basically the same as the optical circuit formation process according to the first embodiment. However, in the optical circuit forming process according to the present embodiment, the inspection port 13a connected to the optical waveguide circuit of the first optical circuit 60A constituting the set is the input / output port of the other second optical circuit 60B constituting the set. Formed on the outside. Similarly, the inspection port 13a connected to the optical waveguide circuit of the second optical circuit 60B is formed outside the input / output port of the first optical circuit 60A.

  Specifically, as shown in FIG. 12, the inspection port 13a connected to the optical waveguide circuit of the first optical circuit 60A constituting the set is connected to the input / output port of the other second optical circuit 60B constituting the set. It is formed near the separation line 16b. The inspection port 13a connected to the optical waveguide circuit of the second optical circuit 60B is formed near the separation line 16b from the input / output port of the first optical circuit 60A. As shown in FIG. 12, in the optical circuit 60, any of the inspection waveguides 13 can be formed in the vicinity of the separation line 16b.

  In the present embodiment, the inspection ports 13a of the optical circuit 60A and the optical circuit 60B constituting the set are formed to face each other. In the optical circuit 30 according to the first embodiment and the optical circuit 50 according to the second embodiment, the inspection port 13a included in the inspection waveguide 13 connected to the optical waveguide circuit is the optical circuit 30 and the optical circuit 50 respectively. Formed inside. However, in the optical circuit 60 according to the present embodiment, the inspection port 13a included in the inspection waveguide 13 connected to the optical waveguide circuit is formed inside the counterpart optical circuit 60 constituting the set.

  In the optical circuit 60AB constituting the set, the end face on which the inspection port 13a is formed and the end faces on which the input / output ports of the input / output waveguide 11 and the input / output waveguide 12 are arranged face each other and are sufficiently separated. Therefore, the influence of stray light generated in each of the inspection port 13a, the input / output waveguide 11 and the input / output port of the input / output waveguide 12 in the optical circuit 60A extends to the inspection port 13a of the optical circuit 60B and other input / output ports. In other words, the influence of stray light generated in each of the inspection port 13a, the input / output waveguide 11 and the input / output ports of the input / output waveguide 12 in the optical circuit 60B extends to the inspection port 13a of the optical circuit 60A and other input / output ports. Absent. In addition, since the inspection waveguides 13 of the optical circuits 60A and 60B pass through the vicinity of the separation line 16b and are guided to the inspection port 13a, the width of the optical circuit 60 in the x direction is equal to the input / output waveguide 11 and the input / output waveguide. It becomes close to the width of the input / output port of the waveguide 12, and the length of the optical circuit 60 in the x direction can be made very small.

  FIG. 13 shows a modification when the optical circuit 60 according to the present embodiment is formed. In FIG. 13 as well, adjacent optical circuits 60 forming a pair are formed point-symmetrically with respect to the center of the boundary line 16a. In FIG. 13, the optical circuit 60AB and the optical circuit 60CD are formed adjacent to each other. The optical circuit 60AB and the optical circuit 60CD are axisymmetric with respect to the separation line 16b.

  Since the optical circuits constituting the set are also point-symmetric in this modified example, the width of the optical circuit 60 can be reduced in the modified example of the present embodiment by arranging the inspection waveguide 13 in a blank area that is not used. can do.

  Next, the separation process according to this embodiment will be described. The separation process according to the present embodiment is basically the same as the separation process according to the first embodiment. However, in this embodiment, the inspection waveguide 13 crosses the boundary line 16a, and the inspection port 13a is formed in the vicinity of the separation line 16b. Further, a part of the inspection waveguide 13 may overlap with the separation line 16b.

  12 and 13 show an example in which even-numbered optical circuits 60 are formed on a wafer by combining two optical circuits 60AB or 60CD in the optical circuit forming step. However, the present invention is not limited to this. The number of optical circuits 60 formed simultaneously on the wafer is arbitrary and may be an odd number. When the odd-numbered optical circuits 60 are formed on the wafer, one optical circuit 60 does not constitute the optical circuit 60AB or the optical circuit 60CD as a pair.

  As described above, in the present embodiment, the optical circuit 60A and the optical circuit 60B constitute an optical circuit 60AB, and the optical circuit 60C and the optical circuit 60D constitute an optical circuit 60CD. The inspection ports 13a of the optical circuit 60A and the optical circuit 60B or the optical circuit 60C and the optical circuit 60D constituting the set are formed so as to face each other. The optical circuit 60 according to the present embodiment is formed point-symmetrically with respect to the center of the boundary line 16a as shown in FIG. In this embodiment, since a part of the inspection waveguide 13 is arranged in the blank area of the adjacent optical circuit 60, the area per one optical circuit 60 can be reduced by the blank area.

  The optical circuit and the manufacturing method thereof of the present invention can be applied to the optical communication industry.

10: Optical circuit 11: Input / output waveguide 12: Input / output waveguide 13: Inspection waveguide 13a: Inspection port 13b: Second endpoint 13c: First endpoint 14: Slab waveguide 15: Array waveguide 16a: Boundary line 16b: separation line 17: waveguide 17a: third end point 17b: fourth end point 18: separation line 20: optical circuits 30, 30A, 30B, 30C, 30D, 30AB, 30CD: optical circuit 31a: first End face 31b: second end face 31c: third end face 31d: fourth end face 50, 50A, 50B, 50AB, 55, 55A, 55B, 55AB: optical circuits 60, 60A, 60B, 60C, 60D, 60AB, 60CD: Optical circuit

Specifically, an optical circuit according to the present invention is for testing an optical waveguide circuit in which a plurality of input / output ports are arranged on a first end face, and the optical waveguide circuit connected to the optical waveguide circuit. And an inspection waveguide, wherein the inspection waveguide is interrupted at a first end point located on a third end surface substantially perpendicular to the first end surface.
The inspection waveguide may be led to an end face different from the third end face.
In addition, an end point connected to the inspection waveguide provided in another optical circuit may be disposed on the third end face or the fourth end face facing the third end face.
Specifically, the bar according to the present invention includes an optical waveguide circuit in which a plurality of input / output ports are arranged on a first end face, and an inspection for inspecting the optical waveguide circuit connected to the optical waveguide circuit. And the input / output port of the first optical circuit of the two adjacent optical circuits is disposed on the first end face, and the second optical circuit of the two optical circuits The input / output port is disposed on an end face opposite to the first end face, and the inspection waveguide of at least one of the first optical circuit and the second optical circuit includes the first optical circuit and the first optical circuit. The first optical circuit and the second optical circuit are characterized by crossing a boundary with the second optical circuit at least once.
The optical circuit according to the present invention may be formed by separating the bar at the boundary.

Claims (9)

An optical waveguide circuit having a plurality of input / output ports disposed on a first end face;
An inspection waveguide for inspecting the optical waveguide circuit connected to the optical waveguide circuit;
With
An optical circuit, wherein the inspection waveguide is interrupted at a first end point located on a third end face substantially perpendicular to the first end face.   The waveguide further guide | induced to the 2nd end surface facing the said 1st end surface from the 2nd end point different from the said 1st end point of the said 3rd end surface is characterized by the above-mentioned. The optical circuit according to 1.   3. The optical circuit according to claim 1, further comprising: a waveguide that connects a third end point and a fourth end point of the third end face.   3. The optical circuit according to claim 1, further comprising: a waveguide that connects a third end point and a fourth end point of the fourth end surface facing the third end surface. 4.   2. The optical circuit according to claim 1, further comprising: a waveguide guided from a third end point of the fourth end surface facing the third end surface to the first end surface.   2. The light according to claim 1, further comprising a waveguide guided to the first end surface from a second end point different from the first end point of the third end surface. circuit. An optical circuit forming step of forming on the wafer a plurality of optical circuits comprising an optical waveguide circuit connected to a plurality of input / output ports and an inspection waveguide connected to the optical waveguide circuit;
A separation step of separating at a boundary between the plurality of optical circuits;
A method of manufacturing an optical circuit having, in order,
In the optical circuit forming step,
The input / output port of the first optical circuit of the two adjacent optical circuits is disposed on the first end surface, and the input / output port of the second optical circuit of the two optical circuits is the first optical circuit. Forming the optical waveguide circuit so as to be disposed on the end face opposite to the end face of
The inspection port connected to the inspection waveguide of the second optical circuit and the inspection port connected to the inspection waveguide of the first optical circuit are arranged on opposite surfaces, and the first optical circuit And a method of manufacturing an optical circuit, wherein the inspection waveguide is formed such that at least one of the inspection waveguides of the second optical circuit crosses the boundary at least once.   The method for manufacturing an optical circuit according to claim 7, wherein the two adjacent optical circuits are in a point-symmetrical relationship.   The optical circuit according to claim 7, wherein an optical circuit having a line-symmetric relationship with the first optical circuit is formed as the second optical circuit with respect to one side of the first end surface. Method.

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