JP2005148129A - Method for manufacturing optical wiring system, and optical wiring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily form an optical waveguide of an optical waveguide layer having a reflecting surface of high optical coupling efficiency. <P>SOLUTION: The optical waveguide of the optical waveguide layer 3 having the reflecting surface of high optical coupling efficiency by metallic reflection in place of total reflection can easily be formed by forming the reflecting mirror of a metallic thin film 7 for an end face 5 of the optical waveguide 3. Moreover, by forming the reflecting mirror of the metallic thin film 7 for the end face 5 of the optical waveguide 3, the reflecting mirror becomes resistant to reduction of the reflectance due to dew condensation and dust in air onto the end face 5 of the optical waveguide layer 3. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical wiring system manufacturing method and an optical wiring system.

  An optical transmission device package (also referred to as “OE-MCM”), which becomes a multichip module by packaging an optical transmission device such as a photoelectric conversion device and an electronic circuit device, includes an optical transmission device, an optical coupling device, and an optical mounting substrate. , A driver electronic circuit element for light emission, an amplification electronic circuit element for light reception, a logic electronic circuit element, and a package, a terminal, an MCM substrate, and the like for sealing the whole.

  Patent Document 1 discloses a configuration example of a conventional optical transmission element package. FIG. 10 is a cross-sectional view schematically showing a configuration example of a conventional optical transmission element package described in Patent Document 1. In FIG. As shown in FIG. 10, the optical transmission element package 100 is arranged with its photoelectric conversion surface facing the optical wiring substrate 101. In the optical wiring board 101, a multi-layered optical waveguide 103 is surface-mounted on the optical transmission element package 100 side on the printed circuit board 102, and a plurality of optical transmission element packages 100 are optically connected by the optical waveguide 103. Making it possible. Such an optical transmission element package 100 is manufactured by packaging an LSI chip 104 and a planar optical element array 105 as an optical transmission element with a transparent resin 106. Further, a microlens 107 is disposed on the surface of the transparent resin 106 of the optical transmission element package 100 and the optical wiring substrate 101, and spatial light propagation is performed by a parallel light flux.

  The electrodes of the surface optical element array 106 are disposed on the side opposite to the optical wiring substrate 101 side, and are bonded to the LSI chip 104 itself as an interposer substrate. The LSI chip 104 is die-bonded to the metal 108 having the flat leads 109 and is also wire-bonded to the flat leads 109. The flat lead 109 is bonded to the printed board 102.

  The light beam emitted from the planar optical element array 106 (here, the light emitting element) disposed in the optical transmission element package 100 is collimated by the microlens 107 on the lower surface of the optical transmission element package 100 and is applied to the printed circuit board 102. On the other hand, the light propagates in the vertical direction and is focused on the optical waveguide 103 by the microlens 107 formed on the upper surface of the optical waveguide 103. At the end face of the optical waveguide 103, a total reflection mirror 110 is formed by an air interface. The condensed beam is subjected to an optical path change of 90 degrees in the total reflection mirror 110 and then guided to each core of the optical waveguide 103. The

  In this way, the optical waveguide 103 having a multilayer structure on the printed circuit board 102 causes the total reflection mirror 110 by the air interface to transmit the propagation light perpendicular to the printed circuit board 102 from the planar optical element array 106 to the propagation light parallel to the printed circuit board 102. The light from the surface optical element array 106 can be coupled to the optical waveguide 103 with high efficiency. Similarly, the propagation light in the direction parallel to the printed circuit board 102 from the optical waveguide 103 is deflected to the propagation light perpendicular to the printed circuit board 102 by the total reflection mirror 110 by the air interface at the end of the optical waveguide 103, It can be coupled to a planar optical element array 106 (here, a light receiving element) that efficiently converts an optical signal into an electrical signal.

JP 2002-189137 A

  However, the total reflection mirror 110 described in Patent Document 1 described above has a very high reflectance and low loss in the case of a light beam with a small incident angle to the optical waveguide 103, but the optical waveguide 103 In the case of a light beam including a component having an incident angle of 5 degrees or more, a light beam having a critical angle or less becomes large, and the loss becomes very large.

  Further, when the total reflection mirror 110 of the optical waveguide 103 is formed by mechanical processing by dicing, the total reflection mirror 110 is processed in a straight line, so that there is a limitation in patterning, and the layout of the optical transmission element package. Therefore, a large restriction is imposed on the optical transmission band, and the optical transmission band is limited. On the other hand, when dry etching is used to form the total reflection mirror 110, the entire substrate needs to be evacuated or decompressed, which is very expensive.

  An object of the present invention is to easily form an optical waveguide of an optical waveguide layer having a reflecting surface with high optical coupling efficiency.

  According to a first aspect of the present invention, there is provided an optical wiring system manufacturing method comprising: an optical waveguide layer provided on a substrate and having an optical waveguide for transmitting an optical signal; and optical coupling of the optical waveguide layer via the optical waveguide. In the manufacturing method of an optical wiring system comprising an optical transmission element, an inverse taper shape forming step in which an end surface of the optical waveguide layer is formed into an inverse taper shape in which the area of the optical waveguide layer decreases as the distance from the optical transmission element increases. And a metal thin film forming step of forming a metal thin film that bends the optical signal on the end face of the optical waveguide layer having the inversely tapered shape.

  Therefore, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is easy to form an optical waveguide of an optical waveguide layer having a reflection surface with high optical coupling efficiency by metal reflection, not total reflection. Is possible. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to a second aspect of the present invention, in the method of manufacturing an optical wiring system according to the first aspect, the metal thin film forming step is performed in the vicinity of an end face of the optical waveguide layer having an inversely tapered shape, and a minute dielectric is formed on the substrate. And forming a metal thin film between the microdielectric and the end face of the optical waveguide layer.

  Therefore, the microdielectric material in a portion different from the optical waveguide layer can control the hydrophilic state, shape, and accuracy thereof independently of the optical waveguide layer, so that a metal thin film can be easily formed. Thus, a metal thin film can be more easily produced.

  According to a third aspect of the present invention, there is provided an optical wiring system manufacturing method comprising: an optical waveguide layer provided on a substrate and having an optical waveguide for transmitting an optical signal; and optical coupling of the optical waveguide layer via the optical waveguide. In a manufacturing method of an optical wiring system including an optical transmission element, a microdielectric forming step for forming a microdielectric on the substrate, and a metal thin film for bending an optical signal is formed on the microdielectric formed A metal thin film forming step, wherein the optical waveguide layer is provided in contact with the metal thin film formed on the microdielectric.

  Therefore, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is easy to form an optical waveguide of an optical waveguide layer having a reflection surface with high optical coupling efficiency by metal reflection, not total reflection. Is possible. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to a fourth aspect of the present invention, there is provided an optical wiring system manufacturing method comprising: an optical waveguide layer provided on a substrate and having an optical waveguide for transmitting an optical signal; and optical coupling of the optical waveguide layer via the optical waveguide. In a manufacturing method of an optical wiring system including an optical transmission element, a microdielectric forming step of forming a microdielectric having a negative shape with respect to the shape of the end face of the optical waveguide layer on the substrate, An optical waveguide layer forming step of forming the optical waveguide layer in contact with the micro dielectric, and the area of the optical waveguide layer decreases as the micro dielectric is removed from the substrate and away from the optical transmission element A reverse taper shape forming step of forming an end surface of the optical waveguide layer having a reverse taper shape, and a metal thin film forming step of forming a metal thin film that bends an optical signal on the end surface of the optical waveguide layer of the reverse taper shape. To Bei.

  Therefore, the shape processing step of the reflecting mirror of the optical waveguide layer is not required, and the transfer negative pattern of the optical waveguide layer is formed as a microdielectric as a member different from the optical waveguide layer in advance, so that the optical transmission element has a multilayer structure. The mirror portion of the optical waveguide layer having an inversely tapered shape in which the area of the optical waveguide layer decreases with distance from the substrate can be easily manufactured as a tapered structure with respect to the substrate. Thereby, it becomes possible to provide a method for manufacturing an optical wiring system with higher economic efficiency.

  According to a fifth aspect of the present invention, in the method for manufacturing an optical wiring system according to the third or fourth aspect, the microdielectric has a curved surface structure except for a portion in contact with the end face of the optical waveguide layer.

  Accordingly, the reflection mirror surface itself of the metal thin film on the minute dielectric is also reduced in its roughness, so that the optical coupling is achieved by improving the shape accuracy and reducing the surface roughness of the reflection mirror. Efficiency can be improved. Thereby, an optical wiring system with high energy efficiency can be provided.

  According to a sixth aspect of the present invention, in the method for manufacturing an optical wiring system according to any one of the first to fifth aspects, the metal thin film is formed using electroless plating.

  Therefore, a metal thin film can be easily produced only on the end face of the optical waveguide layer.

  According to a seventh aspect of the present invention, in the method for manufacturing an optical wiring system according to any one of the first to sixth aspects, the metal thin film is a copper thin film.

  Therefore, when a surface emitting semiconductor laser (VCSEL: Vertical Cavity Surface-Emitting Laser), which is an optical transmission element in the visible band with a wavelength of 850 nm, is used as the optical transmission element, Compared to the case of a reflective film made of gold or silver, it is possible to obtain a metal reflectance that is much higher than that of a metal.

  The invention according to claim 8 is the method of manufacturing an optical wiring system according to any one of claims 3 to 7, wherein the fine dielectric is a photosensitive material layer formed by applying a photosensitive material on the substrate. After forming a multi-tone ultraviolet exposure portion by exposing the UV light to multi-tone, the photosensitive material layer is developed.

  Therefore, by optimizing the γ characteristics of the photosensitive material and increasing the solubility of the exposed part in the developer, a tapered micro-dielectric with a small area on the top of the substrate can be obtained with high accuracy by the exposure and development process. It can be created easily.

  According to a ninth aspect of the present invention, in the method for manufacturing an optical wiring system according to the eighth aspect, multi-tone exposure is performed by a multi-tone exposure system using a spatial modulation element and laser light.

  Therefore, by arbitrarily controlling the data input to the spatial modulation element, the area distribution of the multi-tone exposure can be easily changed. Therefore, a very small dielectric material corresponding to each individual design design on each substrate can be used. Can be easily formed at high speed.

  According to a tenth aspect of the present invention, in the method for manufacturing an optical wiring system according to the ninth aspect, the multi-tone exposure system is also used for forming a microlens for collecting incident / exit light in the optical transmission element.

  Therefore, there is no need to provide an extra device in the line, which is very economical.

  According to an eleventh aspect of the present invention, in the method for manufacturing an optical wiring system according to the eighth aspect, multi-tone exposure is performed by a multi-tone exposure system using a spatial modulation element and a multi-tone mask.

  Therefore, since a multi-tone fixed pattern can be formed in advance on a multi-tone mask, the resolution can be improved.

  According to a twelfth aspect of the present invention, in the method for manufacturing an optical wiring system according to the eleventh aspect, the multi-tone exposure system is also used to form a microlens that collects incident / exit light in the optical transmission element.

  Therefore, there is no need to provide an extra device in the line, which is very economical.

  An optical wiring system according to a thirteenth aspect of the present invention is optically coupled via a substrate, an optical waveguide layer provided on the substrate and having an optical waveguide for transmitting an optical signal, and the optical waveguide of the optical waveguide layer. An optical transmission element formed on the optical waveguide layer, and formed on the end surface of the optical waveguide layer and an end surface of the optical waveguide layer that decreases in area as the distance from the optical transmission element decreases. A metal thin film that bends.

  Therefore, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is easy to form an optical waveguide of an optical waveguide layer having a reflection surface with high optical coupling efficiency by metal reflection, not total reflection. Is possible. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  An optical wiring system according to a fourteenth aspect of the present invention is optically coupled via a substrate, an optical waveguide layer provided on the substrate and having an optical waveguide for transmitting an optical signal, and the optical waveguide of the optical waveguide layer. An optical transmission element formed on the optical waveguide layer and having an inversely tapered end face that decreases in area as the distance from the optical transmission element increases, and is near the end face of the optical waveguide layer and the base And a metal thin film formed between the micro dielectric and the end face of the optical waveguide layer.

  Therefore, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is easy to form an optical waveguide of an optical waveguide layer having a reflection surface with high optical coupling efficiency by metal reflection, not total reflection. Is possible. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to a fifteenth aspect of the present invention, in the optical wiring system according to the thirteenth or fourteenth aspect, the metal thin film is a copper thin film.

  Therefore, for example, when a VCSEL in the visible band with a wavelength of 850 nm is used as the optical transmission element, a very high metal reflectance can be obtained as compared with the case of a reflective film made of aluminum, and it is made of gold or silver. The same metal reflectance as in the case of the reflective film can be obtained.

  According to the method of manufacturing the optical wiring system of the first aspect, since the reflection mirror on the end face of the optical waveguide layer is formed of the metal thin film, reflection with high optical coupling efficiency by metal reflection instead of total reflection. An optical waveguide having an optical waveguide layer having a surface can be easily formed. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to the second aspect of the present invention, since the microdielectric of the portion different from the optical waveguide layer can control the hydrophilic state, shape and accuracy independently of the optical waveguide layer, the metal thin film can be easily formed. Thus, a metal thin film can be more easily produced.

  According to the third aspect of the present invention, since the reflection mirror on the end face of the optical waveguide layer is formed of the metal thin film, the optical waveguide layer having a reflection surface with high optical coupling efficiency due to metal reflection instead of total reflection. An optical waveguide can be easily formed. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to the invention of claim 4, since the shape processing step of the reflection mirror of the optical waveguide layer is unnecessary, the transfer negative pattern of the optical waveguide layer is formed in advance as a minute dielectric as a member different from the optical waveguide layer. Since the mirror part of the optical waveguide layer, which has a multi-layered structure and has an inversely tapered shape in which the area of the optical waveguide layer decreases as it moves away from the optical transmission element, can be easily manufactured as a tapered structure with respect to the substrate. It becomes possible to provide a method for manufacturing an optical wiring system with high economic efficiency.

  According to the fifth aspect of the present invention, since the micro-roughness of the reflective mirror surface of the metal thin film on the micro-dielectric is also reduced, the shape accuracy is improved and the surface roughness of the reflective mirror is reduced. As a result, the optical coupling efficiency can be improved, so that an optical wiring system with high energy efficiency can be provided.

  According to invention of Claim 6, a metal thin film can be easily produced only in the end surface of an optical waveguide layer by forming a metal thin film using electroless plating.

  According to the seventh aspect of the invention, since the metal thin film is a copper thin film, for example, when a VCSEL in a visible band with a wavelength of 850 nm is used as an optical transmission element, compared with a reflective film made of aluminum. Therefore, a very high metal reflectance can be obtained, and the same metal reflectance as that of a reflective film made of gold or silver can be obtained.

  According to the eighth aspect of the invention, by optimizing the γ characteristics of the photosensitive material and enhancing the solubility of the exposed portion in the developer, the taper-shaped microscopic area having a small area at the upper portion of the substrate by the exposure and development processes. The dielectric can be made very easily with high accuracy.

  According to the ninth aspect of the present invention, the area distribution of the multi-tone exposure can be easily changed by arbitrarily controlling the data input to the spatial modulation element. Can be formed very easily and at high speed.

  According to the invention described in claim 10, there is no need to provide an extra device in the line, which is very economical.

  According to the eleventh aspect of the present invention, since the multi-tone fixed pattern can be formed in advance on the multi-tone mask, the resolution can be improved.

  According to the invention of the twelfth aspect, it is not necessary to provide an extra device in the line, which is very economical.

  According to the optical wiring system of the thirteenth aspect of the invention, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, the reflection surface has a high optical coupling efficiency by metal reflection instead of total reflection. The optical waveguide of the optical waveguide layer can be easily formed. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to the optical wiring system of the fourteenth aspect of the present invention, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, the reflection surface has a high optical coupling efficiency by metal reflection instead of total reflection. The optical waveguide of the optical waveguide layer can be easily formed. In addition, since the reflection mirror on the end face of the optical waveguide layer is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide layer.

  According to the fifteenth aspect of the present invention, since the metal thin film is a copper thin film, for example, when a VCSEL in a visible band with a wavelength of 850 nm is used as an optical transmission element, compared with a reflective film made of aluminum. Therefore, a very high metal reflectance can be obtained, and the same metal reflectance as that of a reflective film made of gold or silver can be obtained.

[First embodiment]
A first embodiment of the present invention will be described with reference to FIG.

  FIG. 1 is a schematic diagram showing a method of manufacturing an optical wiring system as a first embodiment of the present invention.

  As shown in FIG. 1A, an under cladding layer 2, a core layer 3 that is an optical waveguide layer having an optical waveguide, and a resist layer 4 are formed on a substrate 1 in this order. Since the formation of the under-cladding layer 2, the core layer 3, and the resist layer 4 is well known, a description thereof is omitted here. As the substrate 1, substrates made of various materials such as a glass substrate, a ceramic substrate, and a polymer substrate can be used. More specifically, the substrate 1 may be a glass-epoxy composite electric wiring board, a glass-fluorine compound composite electric wiring board, a ceramic electric wiring board, or the like. Although not particularly illustrated, the wiring is provided on the substrate 1 and in the substrate 1 and through holes. The undercladding layer 2 preferably has high adhesion to the substrate 1 and the underlayer and has a small difference in thermal expansion coefficient. An intermediate layer may be provided between the under-cladding layer 2 and the core layer 3, the under-cladding layer 2 and the substrate 1, and the core layer 3 and the resist layer 4. The absorption coefficient and refractive index of such an intermediate layer must be designed to be the lowest as one of the optical waveguide configurations. As the optical waveguide material, epoxy resin, acrylic resin, polysilanol resin, polysilane, glass or the like can be used when the propagation light is from near infrared light to visible light. Note that when part of the core layer 3 is removed by dicing, the resist layer 4 may not be provided, but an upper covering layer may be provided as a protective layer for the core layer 3.

  Subsequently, as shown in FIG. 1B, the resist layer 4 is exposed to a predetermined pattern by an exposure apparatus and then developed to dissolve the resist layer 4 in the exposed portion. A shape is formed and patterned.

  In this state, as shown in FIG. 1C, the core layer 3 is etched by dry etching (anisotropic etching) using the resist layer 4 on the core layer 3 as an etching mask, so that the core layer 3 is inversely tapered. An optical waveguide microstructure having a shaped cross-section 5 is formed.

  Next, as shown in FIG. 1 (d), the upper part of the core layer 3 is covered with the resist layer 4, and is immersed in a hydrophilization treatment solution containing a coupling agent to form a section 5. The hydrophilic treatment portion 6 is formed. In addition, when the optical waveguide material originally has a hydrophilic surface such as glass, this hydrophilic treatment need not be performed. The hydrophilic portion of the end face of the optical waveguide is subjected to a hydrophilic treatment directly by inkjet, printing or light irradiation, in addition to the hydrophilic treatment of the exposed portion by masking with the resist layer 4 or printing layer by exposure patterning. Even effective. It is also effective to appropriately apply a lipophilic treatment or to provide a protective film.

  Thereafter, as shown in FIG. 1E, the resist layer 4 is removed by polishing, chemical treatment or dry etching.

  After removing the resist layer 4 in this way, as shown in FIG. 1 (f), all or part of the resist layer 4 is immersed in an electroless plating solution of copper, and a copper electroless plating film is formed on the hydrophilized portion 6. (Metal thin film) 7 is formed. It is also effective to increase the thickness of the metal thin film by further electrolytic plating on the electroless plating. As described above, since the plating layer can be selectively provided on the hydrophilic treatment portion 6 easily by electroless plating, the metal thin film 7 can be easily produced only on the end surface of the core layer 3 (optical waveguide). It is also effective to later remove the electroless plated portion formed on the unnecessary surface by etching with laser or photolithography. Further, in addition to forming the metal reflection film from only copper, combining the reflection film made of copper and another metal is effective for improving the adhesion of the metal and improving the reflectance.

  Next, a polymer film made of a thermoplastic material patterned in advance is brought into close contact with the core layer 3 and the undercladding layer 2 and pressed to level the substrate 1 as shown in FIG. 1 (g). The overclad layer 8 is formed.

  Finally, as shown in FIG. 1H, a wiring electrode 9 is formed on the over clad layer 8 by copper foil pressure bonding and etching.

  Then, as shown in FIG. 1H, a surface emitting semiconductor laser (VCSEL: Vertical Cavity Surface-Emitting Laser) 10 (or an interposer substrate on which the VCSEL 10 is mounted), which is a separately manufactured light transmission element, is connected to this wiring. By performing bump mounting on the electrode 9 by flip chip, an optical wiring system is configured. Here, 11 is a light emitting surface of the VCSEL 10, 12 is a wiring electrode provided in the VCSEL 10, 13 is a solder bump for electrically coupling the wiring electrode 9 and the wiring electrode 12 provided in the VCSEL 10, 14 Is an emitted light beam from the VCSEL 10.

  Here, in the case where the VCSEL 10 in the visible band with a wavelength of 850 nm is used, the use of the copper electroless plating film 7 (metal thin film made of copper) makes it extremely higher than the case of the reflective film made of aluminum. Metal reflectivity can be obtained, and the same metal reflectivity as in the case of a reflective film made of gold or silver can be obtained.

  With the optical wiring system manufacturing method as described above, it is possible to easily form an optical waveguide having a reflective surface with high optical coupling efficiency due to metal reflection instead of total reflection.

  Further, in the manufacturing method of the optical wiring system as described above, since the reflection mirror at the end face of the optical waveguide is formed of a metal thin film, it is difficult for the reflectance to be reduced due to condensation or dust in the air on the end face of the optical waveguide. .

  The reflection mirror made of electroless plating as described above uses an optical waveguide formed on an auxiliary substrate mounted on a main substrate smaller than the main substrate, which is different from the substrate having the optical waveguide serving as the main substrate. It is also effective as a method of manufacturing a part of the optical wiring system for the optical waveguide on the auxiliary substrate when configuring the optical wiring system.

  In FIG. 1, the VCSEL 10 that is a light emitting element is applied as the light transmission element, but a PD (Photo Detector) that is a light receiving element may be applied as the light transmission element. By providing such an optical wiring system equipped with a PD and an optical wiring system equipped with a VCSEL 10 as a pair, data transmission by optical transmission can be performed.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIG. In addition, the same part as 1st embodiment mentioned above is shown with the same code | symbol, and description is also abbreviate | omitted (same also about subsequent embodiment). This embodiment is different from the first embodiment described above in the method of forming the over cladding layer.

  FIG. 2 is a schematic diagram showing a method for manufacturing an optical wiring system as a second embodiment of the present invention.

  2 (a) to 2 (f) are not different from FIGS. 1 (a) to 1 (f) of the first embodiment described above, and a description thereof will be omitted.

  When the copper electroless plating film 7 is formed, as shown in FIG. 2G, an over clad layer 15 is formed on the core layer 3 and the under clad layer 2 by spin coating, and post-baking or light irradiation is performed. And completely cured.

  After that, as shown in FIG. 2 (h), the wiring electrode 12 is formed on the over clad layer 15 by copper foil pressure bonding and etching, as in the first embodiment.

  Then, as shown in FIG. 2 (h), a separately manufactured VCSEL 10 (or an interposer substrate on which the VCSEL 10 is mounted) is flip-chip mounted on the wiring electrode 9 to constitute an optical wiring system. To do.

  With the optical wiring system manufacturing method as described above, it is possible to easily form an optical waveguide having a reflective surface with high optical coupling efficiency due to metal reflection instead of total reflection.

  According to the method for forming an optical wiring system of the present embodiment, the reflection mirror on the end face of the optical waveguide can be completely embedded in the overcladding layer 15 by forming the copper electroless plating film 7 that is a metal thin film. As a result, the electrode portion that joins the optical transmission element to the substrate can be brought close to the light reflecting mirror, so that the positional accuracy can be improved. Moreover, since it is completely embedded so as to be shielded from air, it is possible to reduce a decrease in reflectance due to air oxidation of metal reflection.

  Instead of the over clad layer 15, a core buried layer may be provided, and then an over clad layer may be provided. It is also effective to provide two or more over clad layers.

[Third embodiment]
A third embodiment of the present invention will be described with reference to FIG. 3 or FIG.

  FIG. 3 is a schematic diagram showing a method for manufacturing an optical wiring system as a third embodiment of the present invention.

  3 (a) to 3 (c) are not different from FIGS. 1 (a) to (c) of the first embodiment described above, and thus the description thereof is omitted.

  When an optical waveguide microstructure having a cross section 5 is formed in the core layer 3 by etching (anisotropic etching), the resist layer 4 on the core layer 3 is peeled off as shown in FIG. .

  Next, as shown in FIG. 3 (e), a minute portion having a hydrophilic portion 20a in the vicinity of the reverse tapered shape (cross section 5) of the end face of the core layer 3 of the optical waveguide formed in advance in FIG. 3 (c). The dielectric 20 is formed. The microdielectric 20 may be produced by combining a film forming technique such as coating, deposition, film adhesion, etc., and photolithography or etching, or may be produced by an ink jet or screen printing technique. For example, after a photosensitive material is applied on the substrate 1 to form a photosensitive material layer, the photosensitive material layer is exposed to multiple gradations of ultraviolet rays to form a multiple gradation ultraviolet exposure portion. Thereafter, the fine dielectric 20 can be formed on the substrate 1 by developing the photosensitive material layer. Further, the hydrophilic portion 20a on the microdielectric 20 may be a single material or a mixture in which the hydrophilic portion can be exposed to the surface in advance, or after the shape of the microdielectric 20 is formed, inkjet or immersion Alternatively, a film forming method and a patterning method may be combined. Thereafter, as shown in FIG. 3E, a copper metal thin film 21 made of electroless copper plating is formed on the microdielectric 20 by dipping in a copper electroless plating bath.

  Thereafter, as shown in FIG. 3 (f), the metal thin film 21 is further thickened by electrolytic plating to fill the gap with the end face of the core layer 3 and coat the outside of the end face of the core layer 3. The coating layer 22 is used. This metal coating layer 22 is also a kind of metal thin film. When the gap is very small, only the copper thin film 21 by electroless plating may be used. A plurality of types of metal thin films other than copper may be provided. That is, the metal coating layer 22 is in close contact with the end face of the optical waveguide and functions as a metal reflection mirror of the optical waveguide.

  Next, as shown in FIG. 3G, an over clad layer 23 is formed on the core layer 3 to produce an optical waveguide having a metal reflecting mirror (metal coating layer 22).

  Finally, as shown in FIG. 3 (h), the wiring electrode 9 is formed on the over clad layer 23 by copper foil pressure bonding and etching.

  Then, as shown in FIG. 3 (h), by separately mounting the VCSEL 10 (or the interposer substrate on which the VCSEL 10 is mounted), which is an optical transmission element, to the wiring electrode 9 by flip chip mounting, Configure the optical wiring system.

  With the optical wiring system manufacturing method as described above, it is possible to easily form an optical waveguide having a reflective surface with high optical coupling efficiency due to metal reflection instead of total reflection.

  According to the method for forming an optical wiring system of the present embodiment, the metal coating layer 22 formed on the microdielectric 20 is caused to function as a reflection mirror with respect to the core layer 3 of the optical waveguide layer. Since the microdielectric 20 of different portions can control the hydrophilic state, shape and accuracy thereof independently of the core layer 3, it is possible to easily form a metal reflection film, and more metal reflection film. Can be easily produced.

  A modification of the minute dielectric 20 will be described with reference to FIG. As shown in FIG. 4, a microdielectric 20 having a hydrophilic portion 20 a is provided on the substrate 1. The microdielectric 20 may be produced by combining a film forming technique such as coating, deposition, film adhesion, etc., and photolithography or etching, or may be produced by an ink jet or screen printing technique. Further, the hydrophilic portion 20a on the microdielectric 20 may be a single material or a mixture in which the hydrophilic portion can be exposed to the surface in advance, or after the shape of the microdielectric 20 is formed, inkjet or immersion Alternatively, a film forming method and a patterning method may be combined. Thereafter, a copper metal thin film 21 made of electroless copper plating is formed on the microdielectric 20 by dipping in a copper electroless plating bath.

  Thereafter, when the under-cladding layer 2, the core layer 3 and the over-cladding layer 23 are formed by laminating materials having fluidity such as spin coating, screen printing, ink jet, etc., the curvature with respect to the fluidity and curing conditions is increased. By optimizing the above, the planarity of the interface between the conventional under-cladding layer 2 or over-cladding layer 23 and the core layer 3 can be improved.

  As shown in FIG. 4, the microdielectric 20 in this modification has a substantially planar portion a corresponding to the core layer 3, and is a portion corresponding to the cladding layers 2 and 23 other than the core layer 3. The micro dielectric structure has a curved surface portion b. Such a microdielectric structure having a curved surface portion b has a diffusing action when a microdielectric having no curved surface portion b is deformed by heat, deformed by wet or dry etching, or formed by exposure. It can be formed by using an optical element or by providing an optical system or an optical element that reduces the resolution.

  With this formation method, the minute roughness of the reflecting mirror surface itself of the metal coating layer 22 is also reduced, so that the shape accuracy is improved and the surface roughness of the reflecting mirror is reduced. The coupling efficiency can be improved.

[Fourth embodiment]
A fourth embodiment of the present invention will be described with reference to FIG.

  FIG. 5 is a schematic diagram showing a method for manufacturing an optical wiring system as a fourth embodiment of the present invention.

  As shown in FIG. 5A, a micro dielectric 30 is formed on the substrate 1. For example, after a photosensitive material is applied on the substrate 1 to form a photosensitive material layer, the photosensitive material layer is exposed to multiple gradations of ultraviolet rays to form a multiple gradation ultraviolet exposure portion. Thereafter, the microdielectric 30 can be formed on the substrate 1 by developing the photosensitive material layer. A hydrophilic portion 30 a is formed on the surface of the micro dielectric 30. The hydrophilic portion 30a may be based on the material characteristics of the microdielectric 30 or may be a surface that has been subjected to a hydrophilic treatment after the microdielectric 30 is formed. When the hydrophilic treatment is performed, the entire surface of the micro dielectric 30 may be used, or the hydrophilic treatment may be performed by patterning. Such a micro dielectric 30 is preferably formed in a negative shape with respect to the shape of the end face of the optical waveguide so that the pattern of the end face of the optical waveguide can be transferred in advance. In addition, it is preferable to deform the surface shape of the microdielectric 30 in accordance with the thickness of the metal thin film formed in the next step described below.

  Thereafter, as shown in FIG. 5B, a copper metal thin film 31 made of electroless copper plating is formed on the surface of the microdielectric 30 by dipping in a copper electroless plating bath. This electroless plating may be formed alone, or it is effective to combine electroplating after electroless plating. In electroless plating, it is possible to give priority to the plating growth rate or to reduce the plating surface roughness by controlling the components and temperature of the electroless plating bath. More preferably, the plating growth rate is prioritized at the initial stage of electroless plating, and conditions are set so that the roughness of the plating surface is at an optical level at the end of the electroless plating growth.

  Next, as shown in FIG. 5C, the under cladding layer 2, the core layer 3, and the over cladding layer 32 are left on the substrate 1 while the metal thin film 31 formed on the micro dielectric 30 and on the surface thereof is left as it is. , And the microdielectric 30 is completely buried, and the surface is an overcladding layer 32.

  Finally, as shown in FIG. 5D, the wiring electrode 9 is formed on the over clad layer 32 by copper foil pressure bonding and etching.

  Then, as shown in FIG. 5D, by separately mounting the VCSEL 10 (or the interposer substrate on which the VCSEL 10 is mounted), which is a separately manufactured optical transmission element, on the wiring electrodes 9 by flip chip, Configure the optical wiring system.

In the manufacturing method of the optical wiring system according to the present embodiment, the shape processing step of the reflecting mirror of the optical waveguide is unnecessary, and the transfer negative pattern of the optical waveguide is formed in advance as the microdielectric 30 as a member different from the optical waveguide. Therefore, the mirror portion of the optical waveguide having a multilayer structure and having an inversely tapered shape in which the area of the core layer 3 decreases as the distance from the VCSEL 10 can be easily manufactured as a tapered structure with respect to the substrate. Thereby, it becomes possible to provide a manufacturing method of a more economical optical wiring system.
Since the microdielectric 30 forms a reflection mirror of an optical waveguide by providing a metal thin film 31 formed by electroless plating of metal on the surface, the material itself constituting the microdielectric 30 needs to be made of metal. Therefore, the fine dielectric 30 can be formed by using various patterning methods such as etching using photolithography, lift-off, nanoimprint, ink jet, screen printing, offset printing, laser ablation, etc. By improving the material cost and the process time, it becomes possible to improve the economic efficiency.

  Further, an intermediate layer may be provided between the minute dielectric 30 and the optical waveguide portion. The intermediate layer can increase adhesion, control the shape, and can be used as an increased reflection dielectric film of the metal thin film 31.

  Further, the minute dielectric 30 may not be completely embedded in the optical waveguide, and may be exposed from the over clad layer 32. Further, the microdielectric 30 may form a metal thin film 31 for a plurality of optical waveguides. Further, the metal thin film 31 of the microdielectric 30 is used as an electrode of an electric wiring system when used simultaneously with an optical wiring system, in addition to being used as a reflection mirror of an optical waveguide, or separately manufactured and mounted on a substrate. You may use as an electrode pad of an element, or an alignment mark.

[Fifth embodiment]
A fifth embodiment of the present invention will be described with reference to FIG.

  FIG. 6 is a schematic diagram showing a method for manufacturing an optical wiring system as a fifth embodiment of the present invention.

  First, as shown in FIG. 6A, a micro dielectric 40 is formed on the substrate 1. For example, after a photosensitive material is applied on the substrate 1 to form a photosensitive material layer, the photosensitive material layer is exposed to multiple gradations of ultraviolet rays to form a multiple gradation ultraviolet exposure portion. Then, the micro dielectric 40 can be formed on the substrate 1 by developing the photosensitive material layer. The minute dielectric 40 is preferably formed in a shape that is negative with respect to the shape of the end face of the optical waveguide so that the pattern of the end face of the optical waveguide can be transferred in advance. In addition, it is preferable to deform the surface shape of the micro dielectric 40 in accordance with the thickness of the metal thin film formed in the next step described below.

  Thereafter, as shown in FIG. 6B, the under-cladding layer 2, the core layer 3, and the over-cladding layer 41 are formed while the fine dielectric 40 is left on the substrate 1 as it is. At least a part is embedded, and the surface is an overclad layer 41.

  Thereafter, as shown in FIG. 6C, the micro dielectric 40 is removed from the substrate 1 by wet etching to form the end face 42 of the optical waveguide.

  Thereafter, unnecessary coupling agent is removed after inserting a coupling agent for hydrophilization treatment into a portion where the micro dielectric 40 is removed by an ink jet method or a printing method, as shown in FIG. A hydrophilic treatment layer 43 is formed on the end face 42 of the optical waveguide. At this time, in order to partially perform the hydrophilic treatment layer 43, it is also effective to previously form a protective layer on the over clad layer 41. The protective layer may be formed after removing the minute dielectric 40. By spraying the hydrophilization treatment liquid from the upper part of the substrate 1, it is possible to perform self-alignment and patterning except for the reverse tapered portion. Further, the over clad layer 41 may be formed continuously in advance.

  Thereafter, as shown in FIG. 6E, the substrate 1 is immersed in an electroless plating bath to form a copper metal thin film 44 made of electroless copper plating on the end face 42 of the optical waveguide.

  Although not particularly shown in the drawing, as in the first to fourth embodiments described above, a wiring electrode is formed on the upper portion of the overcladding layer 41 by copper foil pressure bonding and etching, and is an optical transmission element separately manufactured. An optical wiring system is configured by mounting a VCSEL (or an interposer substrate on which a VCSEL is mounted) on the wiring electrode by bump mounting using a flip chip.

  In the manufacturing method of the optical wiring system according to the present embodiment, the shape processing step of the reflection mirror of the optical waveguide is unnecessary, and the transfer negative pattern of the optical waveguide is formed in advance as the minute dielectric 40 as a member different from the optical waveguide. Therefore, the mirror portion of the optical waveguide having a multilayer structure and having an inversely tapered shape in which the area of the core layer 3 decreases as the distance from the VCSEL 10 can be easily manufactured as a tapered structure with respect to the substrate. Thereby, it becomes possible to provide a method for manufacturing an optical wiring system with higher economic efficiency.

[Sixth embodiment]
A sixth embodiment of the present invention will be described with reference to FIG.

  FIG. 7 is a schematic diagram showing a method for manufacturing an optical wiring system as a sixth embodiment of the present invention.

  First, as shown in FIG. 7A, a positive photosensitive material layer 71 is formed by applying a positive photosensitive material on the substrate 1. Next, as shown in FIG. 7B, the positive photosensitive material layer 71 is exposed to multiple gradations of ultraviolet rays to form a multiple gradation ultraviolet exposure portion 72. Thereafter, as shown in FIG. 7C, the positive photosensitive material layer 71 is developed to form a micro dielectric 73 on the substrate 1.

  Here, a manufacturing method of a minute dielectric of the optical wiring system by the multi-tone exposure method will be described with reference to FIG. In FIG. 8, 51 is an ultraviolet laser, 52 is a collimator lens, 53 is a homogenizer, 54 is a laser beam, 55 is a polarization beam splitter (PBS), 56 is a reflective spatial light modulator, 57 is a reduction imaging lens, and 71 is A positive photosensitive material layer, 1 is a substrate, 58 is a substrate support member, and 59a and 59b are substrate support member moving means.

  As shown in FIG. 8, the laser light emitted from the ultraviolet laser 51 is incident on the homogenizer 53 via the collimator lens 52, and the beam area intensity is made uniform by the homogenizer 53. The homogenizer 53 can be composed of an aspherical dihedral lens, or can be composed of two sets of fly-eye lenses or four sets of cylindrical lenses. In addition to the homogenizer 53, a laser beam coherent reduction optical element may be combined.

  The laser beam made uniform in this way is reflected by the PBS 55 and enters the reflective spatial light modulator 56. As the PBS 55, a cubic multilayer PBS or a wire grid polarizer can be used. As the reflective spatial light modulation element 56, an element in which a liquid crystal element called LCOS is formed on a silicon substrate, an element in which a reflection mirror and a liquid crystal element are formed on a polysilicon substrate, or the like can be used. In LCOS, the polarization direction can be controlled for each dot, but the reflected light from one dot of LCOS can be controlled in multiple gradations according to externally input data, or the reflected light from multiple dots of LCOS can be controlled by the dither method. By controlling to multiple gradations, it is used as an area gradation reflective mask. In addition, the LCOS can be dynamically vibrated by mechanical means, or pixel shift can be controlled by an optical element such as vertical alignment liquid crystal or TN liquid crystal, so that the area gradation can be controlled to a higher resolution. It is effective.

  The reflected light composed of the laser light reflected by the reflective spatial light modulator 56 is imaged on the positive photosensitive material layer 71 on the substrate 1 by the reduction imaging lens 57. By using a 14 μm LCOS dot and reducing it to 1/20, a 0.7 μm pixel can be formed. Even in the case of LCOS control of binary gradation, the positive photosensitive material layer 71 Thus, 64 gradations can be realized in units of about 5 μm. In addition, when LCOS is used for the exposure of 256 levels of laser light, it is possible to realize exposure of a laser beam having a very large number of gradations of 1024 gradations in units of about 1.4 μm. In these exposures, if necessary, an optical element having a diffusion function or a resolution reduction function is provided in a part of the coupling optical system, thereby eliminating the quantization step even at a discrete number of gradations such as 64 gradations. Thus, it is possible to realize gradation exposure that sufficiently changes as the exposure amount.

  As a result, even in an optical waveguide having a core layer with a core diameter of about 50 μm, by optimizing the γ characteristics of the photosensitive material and enhancing the solubility of the exposed part in the developer, the upper part of the substrate can be exposed and developed. It is possible to produce a taper-shaped microdielectric having a small area with high accuracy and very easily.

  According to such a method for manufacturing a microdielectric in an optical wiring system, the area distribution of the multi-tone exposure can be easily changed by arbitrarily controlling data input to the LCOS. By cooperating with 58 substrate support member moving means 59a and 59b, a minute dielectric corresponding to each individual design of each substrate 1 can be formed very easily and at high speed. In addition to the method of moving the substrate 1 itself, the entire upper exposure optical system or a part thereof may be moved, or a deflection optical means may be combined.

  The electrical wiring system has many types of boards to be manufactured, and electrode pads, through-holes, electrical wiring, etc. can be easily and quickly produced by photolithography and printing processes in response to individual design designs for each board. be able to. However, when a simple transmissive one-dot multi-tone mask or transmissive dither method multi-tone is used as a photolithographic process for patterning, a substrate on which a photolithography mask similar to IC manufacturing is manufactured. It is necessary to prepare for each type, and the cost is inferior when the number of manufactured sheets is small. In the manufacturing method of the optical wiring system according to the present embodiment, a multi-tone mask pattern corresponding to an individual design is formed using a reflective LCOS, and laser irradiation is performed so that even a small number of substrates are very economical. An optical wiring system can be formed with high performance and high speed.

  Note that a diffusing plate or a diffraction grating can be used as the diffusing means provided in the reduction imaging lens 57. Further, when one pixel of LCOS is sufficiently small, the reduction imaging lens 57 may use an equal magnification imaging system or an enlargement image system. In addition, since the laser light captured by the lens of the actual imaging system is affected by diffraction by LCOS or the like, the light utilization by changing the luminous flux that can be transmitted through the aperture corresponding to the area modulation pattern in LCOS. It is very effective to correct and control the spatial light modulation data by LOCS in advance in response to the fluctuation of the resolution and the fluctuation of the resolution due to the fluctuation of the NA of the reflected light and the fluctuation of the area distribution pattern. .

  This optical wiring system manufacturing method is very effective not only for manufacturing micro dielectrics, but also for directly forming a core layer having a reverse taper shape using a photo-curable photosensitive material. Is.

  The above is the description of the manufacturing method of the micro dielectric 73 of the optical wiring system by the multi-tone exposure method.

  When the micro dielectric 73 is formed in this manner, as shown in FIG. 7 (d), the copper metal thin film 74 made of electroless copper plating is immersed in a copper electroless plating bath to form the micro dielectric. 73 is formed.

  Subsequently, as shown in FIG. 7E, the under-cladding layer 2, the core layer 3, and the over-cladding layer 75 are left on the substrate 1 while the metal thin film 74 formed on the micro dielectric 73 and on the surface thereof is left as it is. , The micro dielectric 73 is completely embedded, and the surface is an over clad layer 75. Further, as shown in FIG. 7E, a positive photosensitive material layer 76 is formed again on the over clad layer 75.

  Next, as shown in FIG. 7F, the multi-tone ultraviolet exposure part 77 is formed by exposing the positive photosensitive material layer 76 with multi-tone ultraviolet rays. This multi-tone exposure uses a multi-tone exposure method using a spatial light modulator as shown in FIG. That is, as this multi-tone exposure method, the same method as the formation method of the minute dielectric 73 can be used, so that it is not necessary to provide an extra device on the line, which is very economical.

  Thereafter, as shown in FIG. 7G, the positive photosensitive material layer 76 is developed to form a microlens 78 on the over clad layer 75. Then, as shown in FIG. Over clad layer 79 is formed on top of 78 and over clad layer 75 by spin coating, and is completely cured by post-baking or light irradiation.

  Finally, as shown in FIG. 7I, the wiring electrode 9 is formed on the over clad layer 79 by copper foil pressing and etching. Then, a separately manufactured VCSEL 10 (or an interposer substrate on which the VCSEL 10 is mounted) is flip-chip mounted on the wiring electrode 9 to constitute an optical wiring system.

  The microlens 78 on the overcladding layer 75 can optically couple incident / exited light 80 of the VCSEL 10 (or the interposer substrate on which the VCSEL 10 is mounted) at an optical coupling portion of a reflection mirror (metal thin film 74) formed on the end face of the optical waveguide. it can. At this time, since the microlens 78 can optically combine parallel beams, a small core diameter of 50 μm can be input and output as a parallel beam with a diameter of 200 μm, which is four times or more. It becomes possible to greatly improve, and it becomes possible to realize a manufacturing method of an optical wiring system with higher process speed and higher economic efficiency.

  Here, a modification of the manufacturing method of the micro dielectric of the optical wiring system by the multi-tone exposure method will be described with reference to FIG. The manufacturing method of the micro dielectric shown in FIG. 9 is different from the manufacturing method of the micro dielectric described in FIG. 8 in the configuration of the imaging optical system. Accordingly, the same parts as those in the method for manufacturing the micro dielectric described with reference to FIG.

  As shown in FIG. 8, the imaging optical system according to the present embodiment includes an enlarged imaging lens 61, a transmissive area gradation mask 62, and a reduced imaging lens 63.

  The reflected light composed of the laser light reflected by the reflective spatial light modulator 56 is imaged on the transmissive area gradation mask 62 by the magnifying imaging lens 61, and combined by the transmissive area gradation mask 62. Gradation is controlled. The laser light subjected to complex gradation control in the transmissive area gradation mask 62 is imaged on the positive photosensitive material layer 71 on the substrate 1 by the reduction imaging lens 63.

  By using LCOS made of high-speed ferroelectric liquid crystal of two gradations as the reflective spatial light modulation element 56, and further using this one dot of 25 μm and enlarging to 20 times, the transmission type area gradation mask 62 is obtained. , The transmittance can be controlled in two gradations in units of 500 μm. Further, a plurality of types of multi-tone transmission patterns are formed on the transmissive area gradation mask 62 in units of 500 μm, and the type of transmissive area gradation mask 62 that is desired to be selectively subjected to multi-tone exposure. By switching one pixel of LCOS corresponding to the position and region of the multi-tone transmission pattern with two gray levels, a plurality of types of multi-tone transmission patterns can be easily controlled. The multi-tone transmission pattern of the transmissive area gray scale mask 62 selected in this way is reduced by a factor of 20 using a reduction lens, thereby realizing exposure of multi-tone laser light in units of 250 μm. You can also In these exposures, if necessary, an optical element having a diffusion function or a resolution reduction function is provided in a part of the coupling optical system, thereby eliminating the quantization step even at a discrete number of gradations such as 64 gradations. Thus, it is possible to realize gradation exposure that sufficiently changes as the exposure amount.

  As a result, even in an optical waveguide having a core layer with a core diameter of about 50 μm, by optimizing the γ characteristics of the photosensitive material and increasing the solubility of the exposed part in the developer, the upper part of the substrate is exposed by the exposure and development process. It is possible to very easily produce a minute dielectric having a small forward taper shape with a high area.

  In addition, since the multi-tone fixed pattern can be formed in advance on the transmissive area tone mask 62, the resolution can be improved. In particular, by using the magnifying imaging lens 61, even if the transmissive area gradation mask 62 is formed by the dither method, it can function as a very high resolution multi-gradation mask.

  In the present embodiment, the enlargement imaging lens 61 and the reduction imaging lens 63 are used. However, depending on the object to be exposed, the combination of enlargement, equal magnification, reduction, and the magnification thereof are used. It is also effective to control with an optimally designed zoom lens or an insertion variable power lens.

  In addition to using a binary LCOS (reflection type spatial light modulator 56) and a transmissive area gradation mask 62, multi-gradation is realized by LCOS, and the transmissive area gradation mask 62 is low gradation. It is preferable to optimize depending on the exposure target of the composite multi-gradation degree such as auxiliary use.

It is a schematic diagram which shows the manufacturing method of the optical wiring system of 1st embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the optical wiring system of 2nd embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the optical wiring system of 3rd embodiment of this invention. It is a schematic diagram which shows the modification of a micro dielectric. It is a schematic diagram which shows the manufacturing method of the optical wiring system of 4th embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the optical wiring system of 5th embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the optical wiring system of the 6th Embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the micro dielectric material of the optical wiring system by a multi-tone exposure method. It is a schematic diagram which shows the modification of the manufacturing method of the micro dielectric material of the optical wiring system by a multi-tone exposure method. It is sectional drawing which shows schematically the structural example of the conventional optical transmission element package.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 3 Optical waveguide layer 10 Optical transmission element 7, 21, 22, 31, 44, 74 Metal thin film 20, 30, 40, 73 Micro dielectric

Claims (15)

In an optical wiring system manufacturing method comprising an optical waveguide layer having an optical waveguide that is provided on a substrate and transmits an optical signal, and an optical transmission element that is optically coupled through the optical waveguide of the optical waveguide layer,
An inverse tapered shape forming step in which the end surface of the optical waveguide layer is an inverse tapered shape in which the area of the optical waveguide layer decreases as the distance from the optical transmission element increases.
A metal thin film forming step of forming a metal thin film that bends an optical signal on an end face of the optical waveguide layer having the reverse tapered shape;
An optical wiring system manufacturing method comprising: In the metal thin film forming step, a minute dielectric is formed on the substrate in the vicinity of an end surface of the optical waveguide layer having a reverse taper shape, and a metal thin film is formed between the minute dielectric and the end surface of the optical waveguide layer. Form,
The method of manufacturing an optical wiring system according to claim 1. In an optical wiring system manufacturing method comprising an optical waveguide layer having an optical waveguide that is provided on a substrate and transmits an optical signal, and an optical transmission element that is optically coupled through the optical waveguide of the optical waveguide layer,
Forming a micro dielectric on the substrate;
A metal thin film forming step of forming a metal thin film that bends an optical signal on the formed micro dielectric;
Comprising
The optical waveguide layer is provided in contact with the metal thin film formed on the micro dielectric,
An optical wiring system manufacturing method characterized by the above. In an optical wiring system manufacturing method comprising an optical waveguide layer having an optical waveguide that is provided on a substrate and transmits an optical signal, and an optical transmission element that is optically coupled through the optical waveguide of the optical waveguide layer,
Forming a microdielectric having a shape that is negative with respect to the shape of the end face of the optical waveguide layer on the substrate; and
An optical waveguide layer forming step of forming the optical waveguide layer in contact with the microdielectric;
Removing the microdielectric material from the substrate and forming an end surface of the optical waveguide layer having an inverse tapered shape in which the area of the optical waveguide layer is reduced as the distance from the optical transmission element is increased; and
A metal thin film forming step of forming a metal thin film that bends an optical signal on an end face of the optical waveguide layer having the reverse tapered shape;
An optical wiring system manufacturing method comprising: The minute dielectric has a curved surface structure except for a portion in contact with the end face of the optical waveguide layer.
The method of manufacturing an optical wiring system according to claim 3 or 4, Forming the metal thin film using electroless plating;
6. A method of manufacturing an optical wiring system according to claim 1, wherein The metal thin film is a copper thin film;
A method for manufacturing an optical wiring system according to any one of claims 1 to 6. The fine dielectric is formed by applying a multi-tone exposure to ultraviolet light on a photosensitive material layer formed by applying a photosensitive material on the substrate to form a multi-tone ultraviolet exposure portion, and then forming the photosensitive material layer. Formed by developing,
8. The method of manufacturing an optical wiring system according to claim 3, wherein Multi-tone exposure by a multi-tone exposure system using a spatial modulation element and laser light,
The method of manufacturing an optical wiring system according to claim 8. The multi-tone exposure system is also used to form a microlens that collects incident / exit light in the optical transmission element,
The method of manufacturing an optical wiring system according to claim 9. Multi-tone exposure by a multi-tone exposure system using a spatial modulation element and a multi-tone mask,
The method of manufacturing an optical wiring system according to claim 8. The multi-tone exposure system is also used to form a microlens that collects incident / exit light in the optical transmission element,
The method of manufacturing an optical wiring system according to claim 11. A substrate,
An optical waveguide layer provided on the substrate and having an optical waveguide for transmitting an optical signal;
An optical transmission element optically coupled through the optical waveguide of the optical waveguide layer;
An end surface of an inversely tapered shape that is formed in the optical waveguide layer and the area of the optical waveguide layer decreases as the distance from the optical transmission element increases;
A metal thin film formed on the end face of the optical waveguide layer and bending the optical signal;
An optical wiring system comprising: A substrate,
An optical waveguide layer provided on the substrate and having an optical waveguide for transmitting an optical signal;
An optical transmission element optically coupled through the optical waveguide of the optical waveguide layer;
An end surface of an inversely tapered shape that is formed in the optical waveguide layer and the area of the optical waveguide layer decreases as the distance from the optical transmission element increases;
A minute dielectric formed on the substrate near the end face of the optical waveguide layer;
A metal thin film formed between the minute dielectric and the end face of the optical waveguide layer;
An optical wiring system comprising: The metal thin film is a copper thin film;
The optical wiring system according to claim 13 or 14.

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