JP2015007669A - Method for manufacturing optical waveguide and apparatus for manufacturing optical waveguide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical waveguide and an apparatus for manufacturing an optical waveguide, by which processing to obtain a highly accurately controlled shape in a depth direction can be efficiently carried out and thereby, an optical waveguide having excellent optical characteristics on a processed surface can be easily manufactured.SOLUTION: The method for manufacturing an optical waveguide includes steps of: disposing a member 29 for forming an optical waveguide, a fixed mask (first mask) 22a having a transmissive part 221, and a movable mask (second mask) 22b having a shielding part 223; and processing the member 29 for forming an optical waveguide to obtain an optical waveguide by irradiating the member 29 with a laser beam L5 through the transmissive part 221 while moving the movable mask 22b so as to vary the area of an overlapping region with time where the transmissive part 221 and the shielding part 223 overlap each other. The movable mask 22b is moved in such a manner that the direction (moving direction) of the movable mask 22b intersects a direction where the area of the overlapping region varies with time.

Description

  The present invention relates to an optical waveguide manufacturing method and an optical waveguide manufacturing apparatus.

  The laser processing method that processes a workpiece by irradiating a laser is a non-contact processing method, and an excessive external force is not applied to the workpiece. It has the feature that high-precision processing can be performed. Moreover, it may be possible to process a material that is difficult to machine, which is also useful in this respect.

  In laser processing, a laser generated by a laser oscillator is formed through an optical system such as a mask or a lens, and the workpiece is irradiated with the laser to vaporize the material, thereby forming an arbitrary processing mark.

  For example, Patent Document 1 discloses using an excimer laser to process an inclined surface having an oblique angle of 45 degrees on an optical waveguide and using this as a mirror surface (mirror) for light reflection. Further, it is disclosed that when processing an inclined surface on an optical waveguide by laser processing, only a target region is processed by previously shielding a non-processed surface with a metal mask. Further, Patent Document 1 illustrates an example in which a metal mask is placed on a processed surface, and this metal mask is exemplified to be formed by a method such as vapor deposition, plating, or metal foil transfer.

JP 2002-169042 A

  However, in the case of this method, it is necessary to place a metal mask directly on the processing surface, and there is a problem that the working efficiency is low. In addition, there is a limit to the improvement in position accuracy due to the characteristics of the work of placing a metal mask, and the processing accuracy cannot be sufficiently increased.

  In laser processing, the processing depth can be changed by partially varying the integrated light amount. By utilizing this, it has been studied to freely control the shape of the processing trace in the depth direction so that the shape of the mirror for reflecting light becomes a target shape.

  However, since the shape of the core portion of the optical waveguide is various and it is necessary to form a mirror accordingly, there are many technical problems in controlling the integrated light quantity according to the shape of the mirror to be formed. Must be resolved. Specifically, in order to partially change the integrated light amount, it is necessary to use a mechanism that changes the laser irradiation region over time, such as using a mask that can change the transmission region over time. Such a mechanism has restrictions on driving conditions, such as the direction in which it can be changed with high accuracy. Thus, there are restrictions on changing the irradiation region. For this reason, even if it is going to change the shape of a mirror according to the shape of various core parts, it was not possible to cope with it.

Specific examples will be described below.
FIG. 6 is a perspective view showing a configuration of a conventional optical waveguide manufacturing apparatus, and FIG. 7 shows a laser irradiation region irradiated on a workpiece and its scanning in the optical waveguide manufacturing apparatus shown in FIG. 8 is a perspective view showing an optical waveguide obtained by processing by the optical waveguide manufacturing apparatus shown in FIG. 6, and FIG. 9 is a plan view of FIG.

  An optical waveguide manufacturing apparatus 9 shown in FIG. 6 includes a laser light source 91 that emits a laser L1 in the + X direction of FIG. 6, a mask 92 that forms the laser L1 into a laser L2 by a transmission portion 921, and a laser L2 6 and a reflecting mirror 93 that reflects toward the −Z direction.

  After being reflected by the reflecting mirror 93, the laser L2 formed by the mask 92 reaches the optical waveguide forming member 99 provided on the −Z side of the reflecting mirror 93, and is irradiated to the irradiation region D1. Thereby, in the irradiation area | region D1, vaporization of material arises and the recessed part which has the depth shape according to the integrated light quantity can be processed.

  An optical waveguide forming member 99 shown in FIG. 6 is a member having a long band shape extending in the X direction, and a clad layer 991, a core layer 993, and a clad layer 992 are laminated in this order from the lower side. It is a member. In addition, the core layer 993 is formed with a core portion 994 that is linear in a plan view and a side cladding portion 995 that is the other portion. One end portion 9941 of the core portion 994 is slightly separated from the one end surface 9931 of the core layer 993. As a result, the one end portion 9941 of the core portion 994 is surrounded by the side cladding portion 995 including not only the side surface but also the end surface. It is.

  As shown in FIG. 7, the irradiation region D <b> 1 is set at a position corresponding to the side cladding portion 995 so as to be positioned on the extension line of the optical axis C <b> 1 of the core portion 994 in the optical waveguide forming member 99. . Laser processing is performed at this position to form a recess, whereby an optical waveguide 90 shown in FIG. 8 is obtained.

  Further, the mask 92 is configured to be shifted along the Z direction, and the irradiation region D1 can be scanned in the X direction by this shift. In FIG. 7, a range S1 in which the irradiation region D1 can be scanned in the optical waveguide forming member 99 is indicated by a one-dot chain line.

  Therefore, in the optical waveguide manufacturing apparatus 9 shown in FIG. 6, by controlling the shift speed of the mask 92, the scanning speed of the irradiation region D1 can be changed along the X direction. As a result, the integrated light quantity can be freely controlled in each part of the region along the extension line of the optical axis C1 of the core part 994 on the upper surface of the optical waveguide forming member 99, and an arbitrary shape can be formed in the depth direction. The recessed part 997 which has can be processed. For example, a concave portion 997 including an inclined surface 9971 as shown in FIG. 8 can be obtained by forming a concave portion whose depth gradually increases toward the -X direction in FIG. An optical waveguide 90 having a mirror surface (inclined surface 9971) can be manufactured.

  Incidentally, in the optical waveguide manufacturing apparatus 9 shown in FIG. 6, the shift direction of the mask 92 is only one axis in the Z direction. This is because it is difficult to smoothly shift the mask 92 when the biaxial drive is used, and the mechanism may be complicated and costly.

  In the optical waveguide manufacturing apparatus 9 shown in FIG. 6, since the shift direction is converted by the reflecting mirror 93, the scanning direction of the irradiation region D1 is limited only to the X direction. For this reason, the optical waveguide manufacturing apparatus 9 shown in FIG. 6 can form only a recess having a depth shape (profile) whose depth varies along the X direction of the optical waveguide forming member 99. With the constraint that. That is, the change direction of the depth shape in the concave portion that can be formed in the optical waveguide manufacturing apparatus 9 shown in FIG. 6 is limited to the X direction. As a result, when the normal line N1 of the inclined surface 9971 formed on the optical waveguide forming member 99 is projected on the same plane as the core layer 993, the projected normal line N2 (hereinafter referred to as “projection normal line N2”). .) Is naturally parallel to the X direction, as shown in FIG. Therefore, it can be said that the optical waveguide manufacturing apparatus 9 shown in FIG. 6 has a restriction that only the inclined surface 9971 having the projection normal N2 parallel to the X direction can be formed.

  The optical waveguide 90 is formed with a plurality of recesses 997 as shown in FIGS. Such a plurality of recesses 997 are required to be processed simultaneously in one processing process from the viewpoint of processing efficiency and processing accuracy. In this regard, in the optical waveguide manufacturing apparatus 9 shown in FIG. 6, only when the projection normal N2 of the inclined surface 9971 and the array axis E1 of the plurality of recesses 997 are orthogonal to each other as shown in FIG. Is possible. This is because, in the optical waveguide manufacturing apparatus 9 shown in FIG. 6, as described above, in addition to the restriction that the shift direction of the mask 92 is only one axis in the Z direction, the laser L1 has a rectangular cross section elongated in the Y direction. This is because it has a shape and a change in the cross-sectional shape is generally difficult. The latter restriction is that the cross-sectional shape of the laser L1 has a rectangular cross-sectional shape that is elongated in the Y direction. Therefore, if the arrangement axis E1 of the plurality of concave portions 997 is not parallel to the Y direction, the concave portions 997 are simultaneously formed. It cannot be processed.

  These two restrictions cannot be easily solved because the two-axis driving of the mask 92 is difficult and the replacement of the laser light source 91 is not easy. The simultaneous formation has a problem that it can be applied only when the projection normal N2 of the inclined surface 9971 and the arrangement axis E1 of the plurality of recesses 997 are orthogonal to each other.

  On the other hand, as described above, the shape of the core portion 994 is various, and therefore the inclined surface 9971 to be formed corresponding to the core portion 994 has a shape in which the projection normal N2 is not orthogonal to the array axis E1. Things are being considered. In this case, if the number of the concave portions 997 to be formed is small, for example, the optical waveguide forming member 99 can be mounted on an XY stage or the like and driven by two axes on the XY plane. In that case, the position accuracy of the XY stage needs to be extremely high. In particular, it is necessary to move the XY stage with high accuracy in both the X axis and the Y axis, and the movement accuracy is directly reflected in the surface accuracy of the inclined surface 9971 to be formed. Accompany. That is, from the viewpoint of machining efficiency and machining accuracy, it can be said that uniaxial driving is more advantageous than biaxial driving. Further, if the number of the concave portions 997 to be formed increases, the laser L2 protrudes from the scannable range, so that simultaneous formation is difficult in any case.

  For the above reasons, in the conventional method of manufacturing an optical waveguide, when trying to form a recess in a workpiece, the shape in the depth direction is controlled with high precision, with many restrictions on the shape in the depth direction. There was a problem that processing could not be performed efficiently.

  An object of the present invention is to provide an optical waveguide manufacturing method capable of efficiently performing processing in which the shape in the depth direction is controlled with high accuracy, and thereby easily manufacturing an optical waveguide having excellent optical characteristics on the processed surface. And providing an apparatus for manufacturing an optical waveguide.

Such an object is achieved by the present inventions (1) to (7) below.
(1) An arrangement step of arranging an optical waveguide forming member including a core portion and a cladding portion, a first mask having a transmission portion, and a second mask having a shielding portion;
While moving the second mask relative to the first mask so that the area of the overlapping region where the transmissive portion and the shielding portion overlap changes with time, the second mask is moved through the transmissive portion. Processing the optical waveguide forming member by irradiating the optical waveguide forming member with a laser to obtain an optical waveguide, and
In the system based on the first mask, a direction in which the second mask is moved is a moving direction, and a direction in which the area of the overlapping region changes with time is a changing direction. A method of manufacturing an optical waveguide, wherein at least one of the first mask and the second mask is moved so as to intersect a change direction.

  (2) The manufacturing method of the optical waveguide according to (1), wherein an intersection angle between the moving direction and the changing direction is 1 to 89 °.

  (3) Said (1) or (2) in which said 1st mask has several said transmission part, and said 2nd mask has said shielding part more than the number of said transmission parts. The manufacturing method of the optical waveguide as described in any one of.

  (4) The method for manufacturing an optical waveguide according to any one of (1) to (3), wherein the shape of the transmission portion is an elongated shape.

  (5) The above-mentioned optical waveguide forming member is disposed on the first mask so that the long axis of the laser irradiation image transmitted through the transmission part is parallel to the extending direction of the core part (4) The manufacturing method of the optical waveguide as described in).

(6) A laser light source for irradiating a laser toward the optical waveguide forming member, a first mask having a transmissive portion, a second mask having a shielding portion, and the transmissive portion and the shielding portion so as to overlap each other. And a moving mechanism for moving the second mask relative to the first mask so that the area of the overlapping overlapping region changes over time,
In the system based on the first mask, the moving mechanism has a direction in which the second mask moves as a moving direction, and a direction in which the area of the overlapping region changes over time as a changing direction. An optical waveguide manufacturing apparatus configured to move at least one of the first mask and the second mask so that the moving direction and the changing direction intersect each other.

  (7) The light according to (6), wherein the second mask includes a transparent substrate having laser transparency and a shielding film having a shielding property formed on the transparent substrate. Waveguide manufacturing equipment.

  According to the present invention, it is possible to efficiently perform processing in which the shape in the depth direction is controlled with high accuracy, whereby an optical waveguide having excellent optical characteristics on the processed surface can be easily manufactured.

  Further, according to the present invention, an optical waveguide manufacturing apparatus capable of easily manufacturing the optical waveguide is obtained.

It is a perspective view which permeate | transmits and shows partially the optical waveguide manufactured by the manufacturing method of the optical waveguide of this invention. It is a top view of the optical waveguide shown in FIG. It is a perspective view which shows the structure of the manufacturing apparatus of the optical waveguide of this invention. It is a figure which shows typically the positional relationship of the two masks with which the manufacturing apparatus of the optical waveguide shown in FIG. 3 was equipped. It is a top view for demonstrating the method of giving a laser processing with respect to the member for optical waveguide formation, and manufacturing an optical waveguide. It is a perspective view which shows the structure of the manufacturing apparatus of the conventional optical waveguide. It is a top view which shows the irradiation area | region and the scanning direction of the laser irradiated with respect to a to-be-processed object in the manufacturing apparatus of the optical waveguide shown in FIG. It is a perspective view which shows the optical waveguide obtained by processing with the manufacturing apparatus of the optical waveguide shown in FIG. It is a top view of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an optical waveguide manufacturing method and an optical waveguide manufacturing apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

<Optical waveguide>
First, an example of an optical waveguide manufactured by the optical waveguide manufacturing method of the present invention will be described.

  FIG. 1 is a perspective view partially showing an optical waveguide manufactured by the optical waveguide manufacturing method of the present invention, and FIG. 2 is a plan view of the optical waveguide shown in FIG.

  An optical waveguide 1 shown in FIG. 1 has a band shape, and transmits an optical signal between one end and the other end to perform optical communication. FIG. 1 shows only one end portion of the optical waveguide 1.

  An optical waveguide 1 shown in FIG. 1 includes a laminated body 10 in which a clad layer 11, a core layer 13, and a clad layer 12 are laminated from below. In the core layer 13, a long core portion 14 and a side clad portion 15 provided adjacent to the side surface are formed. 1 and 2, the core portion 14 and the side cladding portion 15 in the core layer 13 that can be seen through the cladding layer 12 are also shown by dotted lines or the like.

  The width and height (the thickness of the core layer 13) of the core part 14 are not particularly limited, but are preferably about 1 to 200 μm, more preferably about 5 to 100 μm. Thereby, it is possible to increase the density of the core part 14 while increasing the transmission efficiency of the core part 14. That is, since the number of core portions 14 that can be laid per unit area can be increased, large-capacity optical communication can be performed even in a small area.

  In addition, the number of the core parts 14 formed in the core layer 13 is not particularly limited, but is 1 to 100, for example.

  The optical waveguide 1 is formed with a recess 170 formed by a process of removing a part thereof. The recess 170 shown in FIG. 1 is formed at a position corresponding to the side cladding portion 15 on the extension line of the end portion of the core portion 14. A part of the inner side surface of the recess 170 is constituted by an inclined surface 171 that is inclined with respect to the same plane as the core layer 13. The inclined surface 171 functions as a mirror (optical path conversion unit) that converts the optical path of the core unit 14. That is, the mirror composed of the inclined surface 171 changes the light propagation direction by reflecting the light propagating from the lower side to the upper side of the core portion 14 shown in FIG. 2 toward the back side of the paper surface of FIG. .

  As shown in FIGS. 1 and 2, the inclined surface 171 is a flat surface formed continuously from the cladding layer 12 to the cladding layer 11 through the core layer 13. Further, an upright surface 172 is provided at a position facing the inclined surface 171 on the inner surface of the recess 170. The upright surface 172 is a flat surface continuously formed from the cladding layer 12 through the core layer 13 to the cladding layer 11 and is a surface perpendicular to the same plane as the core layer 13. is there. In the present embodiment, the case where the inclined surface 171 is a flat surface has been described as an example. However, in the present invention, the inclined surface 171 does not necessarily need to be a flat surface, and may be a curved surface as necessary. Alternatively, it may be a flat surface with a partially different inclination angle.

  On the other hand, two surfaces of the inner surface of the concave portion 170 that are substantially parallel to the optical axis of the core portion 14 are also upright surfaces 173 and 174 that are perpendicular to the same plane as the core layer 13.

  The inclined surface 171 and the three upright surfaces 172, 173, and 174 constitute the inner surface of the recess 170.

  Further, the maximum depth of the recess 170 is appropriately set based on the thickness of the laminated body 10 and is not particularly limited, but is preferably 1 to 500 μm from the viewpoint of mechanical strength and flexibility of the optical waveguide 1. And more preferably about 5 to 400 μm. The recess 170 may partially penetrate the stacked body 10.

  Further, the maximum length of the concave portion 170, that is, the maximum length of the component parallel to the optical axis C2 of the core portion 14 in the opening of the concave portion 170 in FIG. 2 is not particularly limited, but the cladding layers 11 and 12 and the core layer From the relationship with the thickness of 13 and the inclination angle of the inclined surface 171, it is preferably about 2 to 1200 μm, more preferably about 10 to 1000 μm.

  Furthermore, the maximum width of the concave portion 170, that is, the maximum length of the component orthogonal to the optical axis C2 of the core portion 14 in the opening of the concave portion 170 in FIG. 2 is not particularly limited, and depends on the width of the core portion 14 and the like. Although it sets suitably, Preferably it is about 1-600 micrometers, More preferably, it is about 5-500 micrometers.

  One concave portion 170 may be formed for one core portion 14, but one concave portion 170 may be provided so as to straddle the plurality of core portions 14. .

  Moreover, when forming the some recessed part 170, those formation positions may mutually be shifted | deviated even if it is the mutually same position in a X direction. Note that, by shifting the position of the concave portion 170 in the X direction, a sufficient separation distance between the concave portions 170 can be secured. For example, when forming one concave portion 170 when forming two adjacent concave portions 170. Can affect the other concave portion 170 and suppress the inconvenience such as a decrease in surface accuracy of the inclined surface 171.

  The shape of the opening of the recess 170 shown in FIG. 1 is a rectangle, but the shape of the opening of the recess 170 processed in the present invention is not limited to this, and may be any shape. For example, a pentagon A polygon such as a hexagon, an ellipse, a circle such as an oval, and the like.

  In addition, since the inclined surface 171 functions as a mirror, the inclination angle is appropriately set according to the direction in which the optical path of the core portion 14 is converted, but the same plane as the core layer 13 is used as a reference surface. The angle (acute angle side) formed by the reference surface and the inclined surface 171 is preferably about 30 to 60 °, and more preferably about 40 to 50 °. By setting the tilt angle within the above range, it is possible to efficiently convert the optical path of the core portion 14 on the tilted surface 171 and to suppress the loss accompanying the optical path conversion.

  On the other hand, the angle (acute angle side) formed by the reference surface and the upright surfaces 172, 173, 174 is preferably about 60 to 90 °, respectively. In each figure, it is illustrated as approximately 90 °. The angle formed by the reference surface and the upright surfaces 172, 173, 174 is not limited to such a range, and may be less than 60 °.

  The constituent materials (main materials) of the core layer 13 and the cladding layers 11 and 12 as described above are, for example, acrylic ether, methacrylic resin, polycarbonate, polystyrene, cyclic ether resin such as epoxy resin and oxetane resin. , Polyamide, polyimide, polybenzoxazole, polysilane, polysilazane, silicone resin, fluorine resin, polyurethane, polyolefin resin, polybutadiene, polyisoprene, polychloroprene, polyester such as PET and PBT, polyethylene succinate, polysulfone, poly Various resin materials such as ethers and cyclic olefin resins such as benzocyclobutene resins and norbornene resins can be used. Note that the resin material may be a composite material in which materials having different compositions are combined. Since these can be easily processed by laser processing, they are suitable as constituent materials for the core layer 13 and the cladding layers 11 and 12.

  Here, when the normal line of each inclined surface 171 formed in the optical waveguide 1 is projected on the same plane as the core layer 13, the projected normal line N3 (hereinafter referred to as “projection normal line N3”). As shown in FIG. 2, it is inclined in both the X direction and the Y direction. Note that “inclined in both the X direction and the Y direction” means that the projection normal N3 is neither parallel nor orthogonal to the X direction, as shown in FIG. However, it refers to a state where neither parallel nor orthogonality is set. Similarly, the optical axis C2 of the core portion 14 is also inclined with respect to both the X direction and the Y direction.

  On the other hand, the optical waveguide 1 is formed with a plurality of (two in each drawing) recesses 170, and the array of these recesses 170 is along an array axis E2 parallel to the Y direction.

  Therefore, in the optical waveguide 1, the projection normal N <b> 3 of the inclined surface 171 (the optical axis C <b> 2 of the core portion 14) and the arrangement axis E <b> 2 of the plurality of recesses 170 are not orthogonal. When the plurality of recesses 170 are arranged in this way, the conventional optical waveguide manufacturing apparatus cannot simultaneously laser process these recesses 170 due to some restrictions on the structure of the device as described above. I had a problem.

  On the other hand, in the optical waveguide manufacturing apparatus 2 to be described later, it is possible to simultaneously process the plurality of recesses 170 in one processing process.

<Optical waveguide manufacturing equipment>
Next, an embodiment of the optical waveguide manufacturing apparatus of the present invention will be described.

  FIG. 3 is a perspective view showing the configuration of the optical waveguide manufacturing apparatus of the present invention, and FIG. 4 schematically shows the positional relationship between two masks provided in the optical waveguide manufacturing apparatus shown in FIG. FIG. 5 is a plan view for explaining a method of manufacturing an optical waveguide by performing laser processing on the optical waveguide forming member.

  The optical waveguide manufacturing apparatus 2 shown in FIG. 3 includes a laser light source 21 that emits a laser L3 in the + X direction of FIG. 3, a fixed mask (first mask) 22a that molds the laser L3 into a laser L5, and a movable mask. (Second mask) 22b and a reflecting mirror 23 that reflects the laser L5 toward the -Z direction in FIG. In addition, the optical waveguide manufacturing apparatus 2 includes a moving mechanism 25 that can shift the movable mask 22b in the Z direction.

  The laser L5 formed by the fixed mask 22a and the movable mask 22b is reflected by the reflecting mirror 23, then reaches the optical waveguide forming member 29 provided on the −Z side of the reflecting mirror 23, and is irradiated to the irradiation region D2. The Thereby, in the irradiation area | region D2, vaporization of material arises and the recessed part which has the depth shape according to the integrated light quantity can be processed.

  The optical waveguide forming member 29 shown in FIG. 3 is a member having a long band shape extending in the X direction, and the clad layer 11, the core layer 13 and the clad layer 12 are laminated in this order from the lower side. It is a member. The core layer 13 is formed with a core portion 14 that is linear in a plan view and a side cladding portion 15 that is the other portion. The one end portion 141 of the core portion 14 is slightly separated from the one end surface 131 of the core layer 13, and as a result, the one end portion 141 of the core portion 14 is surrounded by the side cladding portion 15 including not only the side surfaces but also the end surfaces. It is.

  As shown in FIG. 5, the irradiation region D <b> 2 is set so as to be positioned on the extension line of the optical axis C <b> 2 of the core portion 14 in the optical waveguide forming member 29. Laser processing is performed at this position to form a recess 170, whereby the optical waveguide 1 shown in FIG. 1 is obtained.

Hereinafter, the structure of each part of the optical waveguide manufacturing apparatus 2 will be described in detail.
(Laser light source)
Although it does not specifically limit as the laser light source 21, The thing which can irradiate a uniform light quantity with respect to a comparatively wide area | region is used preferably. Specific examples include various solid-state lasers such as YAG laser, YVO ₄ laser, Yb laser, and semiconductor laser, various gas lasers such as CO ₂ laser, He—Ne laser, and excimer laser. Among these, an excimer laser is preferably used from the viewpoint that the light intensity is uniform and the wavelength is suitable for processing.

  Note that the laser light source 21 according to the present embodiment emits a laser L3 having a rectangular cross-sectional shape with a long axis in the Y direction.

(Reflector)
The reflecting mirror 23 reflects the laser L5 and changes the irradiation direction. By using such a reflecting mirror 23, the emission direction of the laser L3 and the irradiation direction of the laser L5 can be made different, so that the degree of freedom in designing the optical waveguide manufacturing apparatus 2 can be increased. As a result, a smaller device can be realized.

  The optical waveguide manufacturing apparatus 2 may include two or more such reflecting mirrors 23 as necessary.

  Further, the reflecting mirror 23 may be omitted, and the optical waveguide forming member 29 may be directly irradiated with the laser L5 formed by the movable mask 22b.

  In that case, the arrangement of the fixed mask 22a and the movable mask 22b may be switched. That is, the movable mask 22b may be disposed on the laser light source 21 side, and the fixed mask 22a may be disposed on the optical waveguide forming member 29 side. This arrangement can be changed even when the reflecting mirror 23 is used.

  Further, the fixed mask 22a disposed on the optical waveguide forming member 29 side may be disposed in the vicinity of the optical waveguide forming member 29 or in contact with the optical waveguide forming member 29 as necessary. In this case, various masks as will be described later can be used as the fixed mask 22a. However, if necessary, a mask layer formed on the surface of the optical waveguide forming member 29 can be substituted.

(mask)
As described above, the optical waveguide manufacturing apparatus 2 shown in FIG. 3 includes the fixed mask 22a whose position is fixed, and the movable mask 22b provided so as to be movable with respect to the fixed mask 22a.

  Among these, the fixed mask 22a is fixed to the optical waveguide manufacturing apparatus 2, and therefore the laser L3 is always irradiated to the same position of the fixed mask 22a. The fixed mask 22 a includes a plate-like body 220 made of a material that does not transmit light, and two transmission portions 221 that penetrate the plate-like body 220 are formed in a part thereof. The laser L3 irradiated to the fixed mask 22a is shaped by the transmission part 221, and the shaped laser L4 is irradiated to the movable mask 22b located on the + X side of the fixed mask 22a.

  The fixed mask 22a is configured to transmit the laser L3 at the transmitting portion 221 and shield or attenuate the laser L3 at other portions, but is not limited to such a configuration, and partially transmits the laser L3. Any mask may be used as long as it is provided with a transmissive portion 221.

  Specific examples include various photomasks such as chrome masks, emulsion masks, and film masks, and various stencil masks such as metal masks and silicon masks. From the viewpoint of resistance to laser L3, light shielding properties, etc., the stencils A mask is preferably used, and a metal mask is more preferably used.

  On the other hand, the movable mask 22b can be shifted in the Z direction. The movable mask 22b includes a plate-like body 222 made of a light-transmitting material, and a shielding portion (shielding film) 223 that shields light transmission is provided in part of the movable mask 22b. As shown in FIG. 3, a part of the laser L4 irradiated to the movable mask 22b is transmitted through the plate-like body 222, while the remaining part is shielded by the shielding part 223, thereby forming a predetermined shape. The As a result, the shaped laser L5 is applied to the reflecting mirror 23 located on the + X side of the movable mask 22b.

  The movable mask 22b is configured to shield or attenuate the laser L4 at the shielding portion 223 and transmit the laser L4 at other portions, but is not limited to such a configuration, and partially shields the laser L4. Any mask may be used as long as the mask is provided with the shielding portion 223.

  Specifically, a mask of the same type as the fixed mask 22a described above can be used, but a chromium mask, an emulsion mask, or the like is preferably used from the viewpoint of easiness of forming the shielding portion 223.

  Here, FIG. 4 is a plan view when the fixed mask 22a and the movable mask 22b shown in FIG. 1 are viewed from the + X side from these positions. As shown in FIG. 4, two transmissive portions 221 formed on the fixed mask 22a are formed according to the number of concave portions 170 to be formed.

  Each transmission part 221 has a rectangular shape corresponding to the shape of the opening of the recess 170 to be formed. The shape of the transmission part 221 is set according to the shape of the opening of the recess 170, and may be a polygon or a circle as described above, but is preferably set to be an elongated shape. As a result, the length that can be shielded by the shielding part 223 of the movable mask 22b is increased for each transmission part 221, so that the adjustment range of the inclination angle of the inclined surface 171 formed in the recess 170 can be widened. As a result, the optical waveguide 1 having a higher degree of shape freedom can be obtained. A variable magnification optical system such as a lens may be provided in the middle of the optical path of the laser L4 or the laser L5. In that case, the size of the transmission portion 221 can be changed with respect to the size of the opening of the recess 170 to be formed in accordance with the magnification of the optical system. Thereby, for example, the resolution of the exposure region can be increased.

  Further, the number of transmission parts 221 formed on the fixed mask 22a may be any number as long as it is larger than the number of concave parts 170 to be formed. Since the individual difference in the surface accuracy of the inclined surface 171 can be kept small, the optical waveguide 1 having a small variation in transmission characteristics between channels (between the core portions 14) can be efficiently manufactured. It is preferable that a plurality of transmission parts 221 are formed in 22a.

  In addition, the number of shielding parts 223 provided on the movable mask 22b can be made smaller than the number of transmission parts 221 by devising the shape of the shielding part 223, but the transmission parts 221 and the shielding parts 223 are one-to-one. When it corresponds, it should just be set to the number of the permeation | transmission parts 221 or more.

  In FIG. 4, the state in which the shielding part 223 gradually overlaps the transmission part 221 by shifting the movable mask 22b from the state where the transmission part 221 of the fixed mask 22a and the shielding part 223 of the movable mask 22b do not overlap. The locus of the shift of the shielding part 223 is shown by continuously illustrating it.

  When the movable mask 22b is shifted as indicated by an arrow 229 in FIG. 4, a part of the outer edge of the shielding portion 223 is gradually moved along the direction indicated by the arrow 228 in FIG. Thereby, the shielding part 223 gradually covers and hides the transmission part 221 as indicated by the locus 224, and accordingly, the exposed area of the transmission part 221 gradually decreases. As a result, the laser L4 shaped by the transmission part 221 is further shaped by the shielding part 223, and the reflecting laser 23 is irradiated with the shaped laser L5.

  As described above, the optical waveguide manufacturing apparatus 2 is configured so that the area of the overlapping region 227 where the transmission part 221 and the shielding part 223 overlap can be changed with time by gradually shifting the movable mask 22b. As a result, the area of the cross section of the molded laser L5 also changes with time. As a result, the area of the irradiation region D2, which is the region where the laser L5 is irradiated onto the optical waveguide forming member 29, is also the movable mask. It will change over time with the shift of 22b.

  Specifically, although the area of the irradiation region D2 can be changed by the shift of the movable mask 22b, the change range is defined by the shape of the transmission part 221, and in the case of FIG. 5, the irradiation region in the illustrated range S2. The area of D2 changes. Thereby, in each part in irradiation field D2, a difference arises in total amount of light, and the amount of processing changes according to the difference. For example, when the irradiation region D2 shown in FIG. 5 changes so as to further expand from the state shown in the drawing, an inclined surface having a shape in which the side closer to the core portion 14 is shallow and gradually becomes deeper as the distance from the core portion 14 is increased. It becomes. By utilizing this, the concave portion 170 including the inclined surface 171 having a predetermined shape can be formed.

  For example, in the case of the optical waveguide 1 shown in FIG. 2, the optical axis C <b> 2 of the core portion 14 is inclined at an inclination angle θ <b> 2 with respect to the X direction, and the inclined surface 171 formed corresponding to the core portion 14. The projection normal N3 is also inclined at an inclination angle θ2 with respect to the X direction. Therefore, in order to form the concave portion 170 including the inclined surface 171 having such a shape, it is necessary to change the cross-sectional shape of the laser L5 so that the integrated light amount changes along the direction parallel to the projection normal N3. is there. Therefore, when the angle formed by the direction in which the shielding portion 223 is shifted in FIG. 4 (the direction indicated by the arrow 228 in FIG. 4) and the Z direction is the inclination angle θ1, the inclination angle θ1 is set to be equal to the inclination angle θ2. This makes it possible to reliably form the inclined surface 171 having the desired tilt angle (the inclined surface 171 having the projection normal line N3 inclined at the inclination angle θ2 with respect to the X direction).

  Further, the transmission part 221 formed on the fixed mask 22a is preferably formed such that the long axis of the rectangle (the long axis R1 shown in FIG. 4) is inclined at an inclination angle θ1 with respect to the Z direction. Thus, by configuring the shielding part 223 so as to gradually cover the transmission part 221 along the long axis R1, the area of the overlapping region 227 between the transmission part 221 and the shielding part 223 changes with time. Since the direction (indicated by the arrow 228 in FIG. 4) is also inclined at an inclination angle θ1 with respect to the Z direction, the optical waveguide 1 shown in FIG. 2 can be easily formed.

  Note that the crossing angle (in FIG. 4) formed by the direction in which the movable mask 22b is shifted (Z direction in FIG. 4) and the direction in which the area of the overlapping region 227 changes with time (the direction indicated by the arrow 228 in FIG. 4). The tilt angle θ1) shown is not particularly limited as long as it is more than 0 ° and less than 90 °, but is preferably about 1 to 89 °, and more preferably about 10 to 80 °. By setting the crossing angle within the above range, the accuracy of the tilt angle (angle formed by the projection normal N3 and the X direction) of the formed inclined surface 171 can be further increased, and the light with other optical components can be increased. The optical waveguide 1 having high optical performance such as coupling efficiency can be obtained. However, the intersection angle refers to an acute angle among the angles formed by the two directions.

  From the above, according to the optical waveguide manufacturing apparatus 2, even if the driving direction of the movable mask 22b is limited to only the Z direction, the area of the overlapping region 227 is changed in a direction inclined with respect to the Z direction. Can be made. In other words, in the present embodiment, the shift (movement) direction of the movable mask 22b (the Z direction in FIG. 4) and the area of the overlapping region 227 where the transmission portion 221 and the shielding portion 223 overlap with each other change due to the shift of the movable mask 22b. Since the change direction intersects with the inclination angle θ1, as shown in FIG. 2, the projection normal N3 of the inclined surface 171 to be formed is not orthogonal to the array axis E2 of the plurality of recesses 170. Even so, the inclined surface 171 in which the shape in the depth direction (depth shape) is controlled with high accuracy can be efficiently (easily) formed simply by shifting the movable mask 22b in one direction. Thereby, the surface accuracy of the inclined surface 171 is improved, the light reflection efficiency is increased, and an optical waveguide having excellent optical characteristics can be easily manufactured.

  As shown in FIG. 4, in the fixed mask 22a, the arrangement axis E3 where the plurality of transmission parts 221 are arranged is parallel to the Y direction. As described above, the laser light source 21 according to the present embodiment emits the laser L3 having a cross-sectional shape having a rectangular shape with the long axis in the Y direction. When forming simultaneously, it is preferable that the arrangement axis E3 of the plurality of transmission portions 221 formed on the fixed mask 22a is also configured to be parallel to the Y direction. Thereby, even when the projection normal N3 of the inclined surface 171 to be formed is not orthogonal to the array axis E2 of the plurality of recesses 170, a large number of recesses 170 can be formed at the same time. Variations in the depth shape and surface accuracy can be suppressed.

  Moreover, according to the optical waveguide manufacturing apparatus 2, the above-described processing can be performed while the optical waveguide forming member 29, which is a workpiece, is fixed. For this reason, not only the moving elements can be reduced and the processing accuracy can be further increased, but also it is not necessary to use an XY stage or the like, so that the apparatus can be simplified and the cost can be reduced. The present invention does not exclude the use of an XY stage or the like that moves the optical waveguide forming member 29, and the laser L5 is irradiated while the optical waveguide forming member 29 is moved by the XY stage or the like. You may do it.

  In this embodiment, the case where only the movable mask 22b is shifted has been described. However, only the fixed mask 22a may be shifted as necessary, and both the fixed mask 22a and the movable mask 22b are shifted. You may make it make it. When both are shifted, in the system based on the fixed mask 22a, both the fixed mask 22a and the movable mask 22b may be shifted so that the above relationship is relatively established.

  Moreover, in this embodiment, although the shielding part 223 has comprised the rectangle, this shape is not specifically limited, What kind of shape may be sufficient if said relationship is materialized. That is, in this embodiment, the long axis of the shielding part 223 that forms a rectangle is orthogonal to the long axis of the transmission part 221 that also forms a rectangle (the long axis R1 shown in FIG. 4), but at least the outer edge of the shielding part 223 If the part (two long sides of the shielding part 223 shown in FIG. 4) is orthogonal to the long axis of the transmission part 221, the shape of the shielding part 223 is not limited to a rectangle, for example, a parallelogram, A rhombus etc. may be sufficient and several shielding part 223 may be connected.

  In the present embodiment, the case where the projection normal N3 of the inclined surface 171 is parallel to the optical axis C2 of the core portion 14 is described, but the present invention can also be applied to the case where these are not parallel. In this case, the crossing angle of the long axis of the shielding part 223 with respect to the long axis of the transmission part 221 may be changed to an angle other than 90 ° according to the tilt angle of the inclined surface 171.

(Movement mechanism)
The movable mask 22b can be shifted by the moving mechanism 25.

  The moving mechanism 25 may be any mechanism as long as it can shift the movable mask 22b in the Z direction. Specific examples include actuators, hydraulic cylinders, and electric cylinders.

  In the present invention, since the movable mask 22b only needs to be shifted in the Z direction, the moving mechanism 25 need only be one-axis driven. Therefore, the configuration of the optical waveguide manufacturing apparatus 2 can be simplified as compared with the case of including a biaxial driving or triaxial driving moving mechanism, and the optical waveguide manufacturing apparatus 2 can be reduced in size and cost. be able to.

  Further, the uniaxially driven moving mechanism 25 controls the shift amount and the shift speed with higher accuracy than when the movable mask 22b is shifted using both of the two axes in the biaxially driven moving mechanism, for example. Therefore, it is useful from the viewpoint of processing accuracy.

  In addition to the above-described parts, the optical waveguide manufacturing apparatus 2 may include a stage on which the optical waveguide forming member 29 is placed as necessary. As described above, this stage has a function capable of driving the optical waveguide forming member 29 along the X direction, a function capable of driving both in the X direction and the Y direction, and a function capable of driving also in the Z direction. May be added.

  Furthermore, as described above, an optical system that focuses or diverges the laser L4 or the laser L5, or a shutter that temporarily shields the lasers L3, L4, and L5 may be provided.

<Optical waveguide manufacturing method>
Next, an embodiment of an optical waveguide manufacturing method of the present invention will be described.

  In the method of manufacturing the optical waveguide 1 shown in FIG. 1, first, an optical waveguide forming member 29 is set in the optical waveguide manufacturing apparatus 2 shown in FIG. Further, the fixed mask 22a and the movable mask 22b are disposed in a state before the movable mask 22b is shifted (arrangement step).

  At this time, assuming that the laser is transmitted only through the transmission part 221 of the fixed mask 22a and is irradiated onto the optical waveguide forming member 29, the long axis of the laser irradiation image is the core part 14 of the optical waveguide forming member 29. The fixed mask 22a and the optical waveguide forming member 29 are respectively arranged so as to be parallel to the extending direction (optical axis C2 shown in FIG. 2). Thereby, the tilt angle of the formed inclined surface 171 is adjusted to a target angle (in this embodiment, the tilt angle at which the projection normal N3 of the inclined surface 171 and the optical axis C2 of the core portion 14 are parallel). Can do.

  Next, while irradiating the laser L3 from the laser light source 21, the movable mask 22b is shifted so that the area of the overlapping region 227 where the transmission part 221 of the fixed mask 22a and the shielding part 223 of the movable mask 22b overlap changes with time. Let Thereby, since the area of the transmission part 221 changes and the shape of the cross section of the laser L5 also changes thereby, the integrated light quantity of each part in the irradiation area | region D2 can be changed.

  The direction of change of the integrated light quantity at this time can be determined by the shape of the transmission part 221 and the shape of the shielding part 223. In the case of FIG. 4, the shape and shielding of the transmission part 221 are such that the change direction of the area of the overlapping region 227 is inclined by the inclination angle θ1 with respect to the shift direction of the movable mask 22b (the shift direction and the change direction intersect). Since the shape of the portion 223 is set, the optical waveguide forming member 29 has an inclination having a projection normal N3 parallel to a direction inclined by an inclination angle θ2 (θ2 = θ1) with respect to the X direction. A surface 171 can be formed. As a result, the inclined surface 171 having the projection normal line N3 can be formed only by shifting the movable mask 22b in only one direction. When the movable mask 22b is shifted only in one direction, the shift amount and the shift speed can be controlled with high accuracy, and the surface accuracy of the formed inclined surface 171 can be easily increased accordingly. And the optical waveguide 1 excellent in the optical performance of the inclined surface 171 can be manufactured easily.

  The optical waveguide manufacturing method and the optical waveguide manufacturing apparatus of the present invention have been described above, but the present invention is not limited to this.

For example, in the above-described embodiment, the case where the inclined surface (recessed portion) is formed for use as a mirror with respect to the optical waveguide forming member has been described. The present invention can also be applied to a case where a target concave portion or through hole (for example, a concave portion for forming a land portion or a through hole for forming a through wiring) is formed.
Moreover, this inclined surface may be formed in the middle of the core part instead of on the extension line of the core part.

DESCRIPTION OF SYMBOLS 1 Optical waveguide 10 Laminated body 11 Clad layer 12 Clad layer 13 Core layer 131 One end surface 14 Core part 141 One end part 15 Side surface clad part 170 Recess 171 Inclined surface 172 Upright surface 173 Upright surface 174 Upright surface 2 Optical waveguide manufacturing apparatus 21 Laser Light source 22a Fixed mask 220 Plate-like body 221 Transmission portion 22b Movable mask 222 Plate-like body 223 Shielding portion 224 Trajectory 227 Overlapping area 228 Arrow 229 Arrow 23 Reflecting mirror 25 Moving mechanism 29 Optical waveguide forming member C1 Optical axis C2 Optical axis D1 Irradiation Area D2 Irradiation area E1 Array axis E2 Array axis E3 Array axis L1 Laser L2 Laser L3 Laser L4 Laser L5 Laser N1 Normal N2 Projection normal N3 Projection normal R1 Long axis S1 Range S2 Range θ1 Inclination angle θ2 Inclination angle 9 Optical waveguide Manufacturing apparatus 90 optical waveguide 91 laser light source 9 Mask 93 reflector 99 for forming an optical waveguide member 921 transmitting unit 991 cladding layer 992 cladding layer 993 the core layer 994 the core portion 995 side cladding portion 997 recess 9931 end surface 9941 end 9971 inclined surface

Claims (7)

An arranging step of arranging an optical waveguide forming member having a core portion and a clad portion, a first mask having a transmission portion, and a second mask having a shielding portion;
While moving the second mask relative to the first mask so that the area of the overlapping region where the transmissive portion and the shielding portion overlap changes with time, the second mask is moved through the transmissive portion. Processing the optical waveguide forming member by irradiating the optical waveguide forming member with a laser to obtain an optical waveguide, and
In the system based on the first mask, a direction in which the second mask is moved is a moving direction, and a direction in which the area of the overlapping region changes with time is a changing direction. A method of manufacturing an optical waveguide, wherein at least one of the first mask and the second mask is moved so as to intersect a change direction.   The method of manufacturing an optical waveguide according to claim 1, wherein an intersection angle between the moving direction and the changing direction is 1 to 89 °.   3. The optical waveguide according to claim 1, wherein the first mask has a plurality of the transmission parts, and the second mask has the shielding parts equal to or more than the number of the transmission parts. Production method.   The method of manufacturing an optical waveguide according to claim 1, wherein a shape of the transmission portion is an elongated shape.   5. The optical waveguide forming member according to claim 4, wherein the optical waveguide forming member is disposed with respect to the first mask so that a long axis of a laser irradiation image transmitted through the transmission portion is parallel to an extending direction of the core portion. Manufacturing method of optical waveguide. A laser light source for irradiating a laser toward the optical waveguide forming member, a first mask having a transmissive portion, a second mask having a shielding portion, and the transmissive portion and the shielding portion overlap each other. A moving mechanism for moving the second mask relative to the first mask so that the area of the overlapping region changes over time,
In the system based on the first mask, the moving mechanism has a direction in which the second mask moves as a moving direction, and a direction in which the area of the overlapping region changes over time as a changing direction. An optical waveguide manufacturing apparatus configured to move at least one of the first mask and the second mask so that the moving direction and the changing direction intersect each other.   The optical waveguide manufacturing apparatus according to claim 6, wherein the second mask includes a transparent substrate having laser transparency and a shielding film having a shielding property formed on the transparent substrate. .

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