JP2009081225A - Optical communication module and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical communication module capable of avoiding a fault caused by the outflow of an adhesive resin. <P>SOLUTION: According to this optical communication module, an optical path channel through which at least one of transmitted light or received light passes is formed at a semiconductor substrate, and at least one of optical devices is bonded to the semiconductor substrate with the adhesive resin. Further, the adhesive resin is composed of a hydrophobic first resin layer formed on the semiconductor substrate, and a second resin layer formed on the first resin layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an optical communication module used as a communication device and a manufacturing method thereof. The present invention particularly relates to an optical communication module in which optical elements for transmission / reception are collectively mounted on a substrate using a surface mounting method, and a method for manufacturing the same.

  In an optical communication network represented by FTTH (Fiber To The Home), a single-core bidirectional optical communication system is becoming widespread. In the single-core bidirectional optical communication system, the office building and the user are connected by a single optical fiber, and bidirectional communication is performed using two types of light having different wavelengths as transmission signals and reception signals, respectively.

  In a conventional bidirectional optical communication module, a laser module as a transmission unit and a photodiode as a reception unit are packaged separately. Then, these modules (transmission module, reception module) and a wavelength demultiplexer (wavelength filter) that branches the transmission light and the reception light are packaged together. Thereby, bidirectional communication is realized.

  However, in such a system, since it is necessary to separately adjust (such as optical axis adjustment) for the packaged transmission module and the reception module, the manufacturing cost increases. In addition, there is a problem that the entire module becomes large and it is difficult to reduce the size.

  As a method for solving these problems, a single-core bidirectional optical communication module described in Patent Document 1 (Japanese Patent Laid-Open No. 2006-154535) has been proposed. In the module described in Patent Document 2 and the like, the transmitter, the receiver, and the wavelength filter are collectively mounted on one substrate. Thereby, miniaturization and cost reduction of the optical communication module are realized.

  FIG. 1 is a perspective view showing the structure of a conventional single-core bidirectional optical communication module disclosed in Patent Document 1. As shown in FIG. FIG. 2 is a side view showing a state observed from side A (reception side) and side B (transmission side) of FIG. 1 and 2, on a silicon substrate 100 as a support substrate, an alignment mark 109 used for alignment with an element at the time of mounting, and a V groove 101 having a V-shaped cross section when viewed from the lateral direction. , 102 are formed by anisotropic etching. On this substrate 100, a laser chip (LD) 103 that emits light for transmission, a transmission side lens 104, a reception side lens 105, a light receiving element (PD) 106 that converts an optical signal into an electrical signal, a glass element 107, a wavelength The filter 108 is mounted and an optical communication module is manufactured.

  Next, a bidirectional communication method using the optical communication module disclosed in Patent Document 1 will be described. FIG. 3 is a plan view showing an optical path of the conventional optical communication module shown in FIG. FIG. 4 is a side view showing the optical path of the conventional optical communication module shown in FIG. 1 separately for the reception side and the transmission side. As shown in FIGS. 3 and 4, at the time of transmission, the transmission light 119 emitted from the LD 103 is collimated by the nearest lens 204, passes through the wavelength filter 108, and then collects on the optical fiber 112 by the ball lens 114. Be lit.

  At the time of reception, the reception light 120 emitted from the optical fiber 112 is diffracted by the ball lens 114 and then refracted by 90 ° by the reflection film of the wavelength filter 108 to reach the lens 105 on the reception side. The received light 120 is diffracted by the lens 105, passes through the light receiving side V groove 102, is reflected by a reflecting surface (not shown) formed on the terminal surface of the V groove 102, and passes through the glass element 107. It reaches the light receiving surface of the PD 106 mounted on the upper surface.

  In bidirectional communication by the above method, the LD 103 and the PD 106 mounted on one substrate must be electrically and optically separated (insulated) in order to avoid the influence of noise. Therefore, the glass element 107 is disposed between the substrate 100 and the PD 106, and an adhesive resin (122) is used for bonding the substrate 100 and the glass element 107.

  5 to 7 are a top view and a side view showing a part of the assembly process of the conventional optical communication module shown in FIG. 5 shows a state before applying the adhesive resin; FIG. 6 shows a state where the adhesive resin is applied; and FIG. 7 shows a state where the element is mounted on the adhesive resin.

  From the state shown in FIG. 5, first, as shown in FIG. 6, an adhesive resin 122 is applied around the V grooves 101 and 102 of the substrate 100. Next, as shown in FIG. 7, the glass element 107 is pressed and cured by heat and bonded.

  FIG. 8 is an explanatory view (side view) for illustrating problems of the conventional optical communication module shown in FIG. FIG. 9 is an explanatory diagram (side view / reception side optical path) for illustrating the problems of the conventional optical communication module shown in FIG.

  According to the method described in Patent Document 1, as shown in FIG. 8, when the adhesive resin 122 is applied excessively when the adhesive resin 122 is applied, or the glass element 107 is pressed from above the adhesive resin 122 when the element is mounted. Thus, a problem occurs when the resin 122 moves on the substrate 100. That is, a phenomenon in which the adhesive resin 122 flows into the V groove 102 and the alignment mark 109 occurs.

  The alignment mark 109 serves as a reference coordinate for calculating the element mounting position on the substrate 100 in the image recognition process when the element is mounted. For this reason, when the adhesive resin 122 flows into the alignment mark 109, the adhesive resin 122 becomes a shadow, and the alignment mark 109 cannot be accurately recognized. As a result, a recognition error occurs in image recognition, and the element cannot be mounted, or the element position is shifted.

  As shown in FIG. 9, the adhesive resin 122 that has flowed into the V-groove 102 is fixed so as to fill the inside of the V-groove 102, and covers the reflective layer 121. For this reason, the path of the received light 120 that reaches from the optical fiber is blocked by the adhesive resin 122, and the received light cannot normally reach the light receiving portion of the PD 106, and desired reception performance cannot be obtained.

  By the way, the surface of the semiconductor substrate gradually becomes hydrophilic due to the natural oxide film. Or it becomes hydrophilic by performing a thermal oxidation treatment. On the other hand, the resin used for fixing the optical element is hydrophobic. For this reason, it is difficult to control the application range of the adhesive resin, resulting in problems in yield and process time.

  In FIG. 9 of Patent Document 2 (Japanese Patent Laid-Open No. 2004-179578), in order to control the flow of the underfill material, a hydrophobic portion is formed corresponding to the electronic component mounting region on the surface of the solder resist, and It is disclosed that a hydrophilic portion is formed so as to surround the hydrophobic portion.

JP 2006-154535 A JP 2004-179578 A

  The present invention has been made in view of the above situation, and an object of the present invention is to provide an optical communication module capable of avoiding problems due to the outflow of adhesive resin and a method for manufacturing the same.

Another object of the present invention is to provide an optical communication module in which the application range of the adhesive resin can be easily controlled and a method for manufacturing the same.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided an optical communication module in which a plurality of optical elements are mounted on a semiconductor substrate, wherein at least one of transmission light and reception light is included in the semiconductor substrate. An optical path groove is formed, and at least one of the optical elements is bonded to the semiconductor substrate with an adhesive resin. The adhesive resin includes a hydrophobic first resin layer formed on the semiconductor substrate; and a second resin layer formed on the first resin layer. .

  The method for manufacturing an optical communication module according to the second aspect of the present invention includes a step of preparing a semiconductor substrate; a step of forming an optical path groove through which light for reception or transmission passes on the surface of the semiconductor substrate; Forming a hydrophobic first resin layer in a region on the semiconductor substrate on which the optical element is mounted; curing the first resin layer; and forming a first layer on the first resin layer; Forming the second resin layer; mounting the optical element on the resin layer before curing the second resin layer; and mounting the optical element after mounting the optical element. And a step of curing the layer.

Here, the hydrophobic first resin layer needs to have hydrophilicity that is weaker than at least the hydrophilicity of the semiconductor substrate surface. The first resin layer is preferably applied wider than the application range of the second resin layer. Actually, since the second resin layer (adhesive resin) spreads at the time of application or when the optical element is mounted, finally, the application range of the first resin layer and the second resin layer becomes substantially equal.

  According to the present invention configured as described above, by applying the hydrophobic first resin layer as a base on the surface of the hydrophilic semiconductor substrate, the irregularity of the second resin layer applied thereon No protrusion occurs and the adhesive resin can be applied in a desired range.

As a result, the adhesive resin can be prevented from reaching the alignment mark or the optical path groove, the shape of the alignment mark can be maintained, and the optical path inside the optical path groove can be secured.

  The optical communication module according to the present embodiment implements two-way communication of light by mounting both transmitting and receiving elements together on a single silicon substrate 200. A small groove (213) is formed on the silicon substrate 200 in the immediate vicinity of the V-groove (202) for the optical path and the alignment mark (209). This suppresses inflow into the alignment mark (209) and the V-groove (202) due to excessive resin at the time of resin application or element fixing or spread of the resin due to element pressing. As a result, a single element bidirectional optical communication module having a structure that realizes a precise element mounting process and secures an optical path of received light can be obtained.

  FIG. 10 is a perspective view showing the structure of the optical communication module according to the first embodiment of the present invention. FIG. 11 is a side view showing a state observed from the side surface A (reception side) and the side surface B (transmission side) in FIG.

  In the optical communication module according to the present embodiment, an optical path groove (201, 202) through which at least one of transmission light and reception light passes is formed in the semiconductor substrate (200), and at least one of the optical elements is an adhesive resin (222). Is adhered to the semiconductor substrate (200). The adhesive resin (222) includes a hydrophobic first resin layer (250) formed on the semiconductor substrate 200; a second resin layer (252) formed on the first resin layer (250). ).

  As optical elements, a light emitting element (203) that outputs light for transmission (transmission light); a light receiving element (206) that converts received light (received light) into an electrical signal; and a light receiving element (203). The wavelength filter (208) which branches the received light and the transmission light output from a light emitting element (203) can be included.

  As an optical element, an output silicon lens (204) that diffracts the transmitted light output from the light emitting element (203) and an input silicon lens (205) that diffracts the received light incident on the light receiving element (206). Can be included. The input silicon lens (204) is positioned with reference to the optical path groove (201). In addition, at least a part of the bottom surface of the light receiving element (206) is disposed on the optical path groove (202).

  As the first resin layer (250), an acrylic resin containing a long-chain alkyl group or a polyimide resin containing no ether bond can be used. As the second resin layer (252), a thermosetting resin such as a polyimide resin or an epoxy resin can be used.

  The semiconductor substrate 200 is made of a silicon wafer having grooves formed by dicing. As the light emitting element 203, a laser diode (LD) can be used. As the light receiving element 206, a photodiode (PD) can be used.

  The plurality of alignment marks 209 formed on the semiconductor substrate 200 and the V grooves 201 and 202 having a V-shaped cross section when viewed from the lateral direction are formed by anisotropic etching.

  In this embodiment, the light receiving element 206 is fixed on a glass member 207 mounted on the semiconductor substrate 200 by an adhesive resin 222. On the surface of the glass member 207 where the light receiving element 206 is mounted or on the surface opposite to the mounting surface, a reflective film (not shown) that reflects transmitted light is formed. By mounting the light receiving element 206 on the semiconductor substrate 202 via the glass member 207, the light emitting element 203 and the light receiving element 206 mounted on one semiconductor substrate 200 are electrically and optically separated (insulated). The

  The semiconductor substrate 200 is further formed with a plurality of concave alignment marks 209 that define positions on the substrate 200.

  The light receiving element 206 includes a main body portion made of a semiconductor substrate and a light receiving portion formed on the bottom surface side (glass member 207 side) of the main body portion. A wavelength filter (not shown) that blocks unnecessary light such as transmission light output from the light emitting element 203 is provided between the substrate 200 and the glass member 207 (the bottom surface of the glass member 207). .

  The optical transceiver module according to the present embodiment further includes an output silicon lens 204 that diffracts the transmitted light 219 output from the light emitting element 203, and an input silicon lens 205 that diffracts the received light 220 incident on the light receiving element 206. It has. Here, the silicon lenses 204 and 205 are positioned with reference to the optical path grooves 201 and 202 having a V-shaped cross section. At least a part of the bottom surface of the light receiving element 206 is disposed on the optical path groove 202. The optical path groove 202 is provided with a reflecting member (224) that guides the received light 220 diffracted by the input silicon lens 205 to the light receiving element 206.

  As shown in FIG. 10 and the like, the silicon lenses 204 and 205 have a structure in which a cylindrical lens portion having the same thickness is formed on a prismatic support portion. The outer periphery of the cylindrical lens portion is centered by contacting the inclined inner wall surfaces of the optical path grooves 201 and 202 having a V-shaped cross section.

  The basic configurations of the silicon lenses 204 and 205; the wavelength filter 208; the light emitting element 203; the light receiving element 206; and the optical path grooves (V grooves) 201 and 202 are disclosed in Japanese Patent Laid-Open No. 2006-154535. Can be used.

  FIG. 12 is a plan view showing an optical path of the optical communication module according to the first embodiment shown in FIG. FIG. 13 is a side view showing the optical path of the optical communication module according to the first embodiment shown in FIG. 10 separately for the reception side and the transmission side. A bidirectional communication method using the optical communication module of this embodiment will be described. As shown in FIGS. 12 and 13, during transmission, the transmission light 219 emitted from the LD 203 is collimated by the nearest silicon lens 204. Thereafter, the light enters the ball lens 214 through the wavelength filter 208 and is collected on the optical fiber 212.

  On the other hand, at the time of reception, the received light 220 emitted from the optical fiber 212 is diffracted by the ball lens 214 and then refracted by 90 ° by the reflection film of the wavelength filter 208 to reach the receiving-side silicon lens 205. The received light 220 is diffracted by the silicon lens 205, passes through the light path groove 202 on the light receiving side, and reaches the reflecting surface 224 (see FIG. 17) formed on the terminal surface of the groove 202. The light reflected by the reflecting surface 224 of the groove 202 reaches the light receiving surface of the light receiving element 206 mounted on the upper surface via the glass element 207.

  In processing (manufacturing) the silicon substrate 200 used in the optical communication module according to this embodiment, first, a resist is applied on the substrate 200, and a V-groove pattern (for mounting elements) based on the substrate design drawing ( 201, 202), an alignment pattern for alignment (209), and a filter mounting surface preparation pattern (248). Next, the substrate 200 is wet etched to form V grooves 201 and 202 for mounting elements and alignment marks 209 for alignment. At this time, the depth of each groove is determined by the etching time and the pattern width. The narrower the pattern width, the smaller the depth.

  Next, dicing is performed along a dicing line 205 in order to obtain a cross section of the V grooves 201 and 202 for mounting elements. Thereafter, dicing is performed along dicing lines 252 to separate the substrates, and the chips are separated into individual pieces.

  14 to 18 are a top view and a side view showing a part of the manufacturing process of the optical communication module according to the present embodiment, showing the process after the chips are separated. The application of the adhesive resin and the mounting of an optical element such as a silicon lens can be performed before the chips are separated.

  The method for manufacturing an optical communication module according to the present invention includes a step of preparing a semiconductor substrate 200; a step of forming optical path grooves (201, 202) through which light for reception or transmission passes on the surface of the semiconductor substrate 200; Forming a hydrophobic first resin layer (250) in a region on the semiconductor substrate 200 on which the optical elements (204, 205...) Are mounted; and curing the first resin layer (250). And; forming a second resin layer (252) on the first resin layer (250); and before curing the second resin layer (252), on the resin layer (252) A step of mounting the optical elements (204, 205...); And a step of curing the second resin layer (252) after mounting the optical elements (204, 205...).

  First, as shown in FIG. 14, the optical path grooves 201 and 202; the alignment mark 209; the first protection groove 213a; and the second protection groove 213b are formed in advance on the semiconductor substrate 200. These grooves 201, 202, 209, 213a, and 213b are formed by a well-known photolithography technique and anisotropic etching. A reflective film 224 is formed at the end of the optical path groove 202 on the receiving side.

  Next, as shown in the figure, an electrode pad 240 is formed at the end of the optical path groove 201 on the transmission side, and a solder film 242 for bonding the light emitting element 203 is further formed thereon. Thereafter, the light emitting element 203 is bonded and mounted on the solder film 242. At this time, the light emitting element 203 is picked up by a surface mounter, and the mounting coordinates of the light emitting element 203 are calculated from the alignment mark 209 placed on the semiconductor substrate 200 by image recognition. Thereafter, the center coordinates of the light emitting element 203 are similarly calculated by image recognition, and the position of the light emitting element 203 is adjusted by the surface mounter so that the two coordinates coincide. When the light emitting element 203 and the electrode pad 240 are connected via the solder film 242, the light emitting element 203 is pressure-bonded to the solder film 242, and then heat treatment is performed at a specified pressure and temperature (about 350 to 400 degrees).

  Next, as shown in FIG. 15, a hydrophobic first resin 250 is coated on the region where the optical element is mounted. The first resin 250 can be applied to the substrate 200 by, for example, spin coating, and thereafter, the hydrophobic resin is fixed (cured) at a target position by being irradiated with light and polymerized. As described above, as the first resin layer 250, an acrylic resin containing a long-chain alkyl group or a polyimide resin containing no ether bond can be used.

  Next, as shown in FIG. 16, a hydrophobic second resin layer (adhesive resin) 252 is applied on the first resin layer 250. At this time, since the hydrophobic resin aggregates away from the hydrophilic portion, the protrusion of the resin from a desired place is reduced. At this time, the second resin layer 252 is not cured.

  Subsequently, the optical elements are mounted on the second resin 252. The order of mounting the elements is basically the order of elements that require heat treatment at a high temperature and elements that require low-temperature treatment. It is preferable to make it. Further, the mounting position of each element is set by prior optical design.

  As shown in FIG. 17, a silicon lens 204 for collimating and emitting light from the light emitting element 203 is mounted. As in the case of the light emitting element 203, the silicon lens 204 is picked up by a surface mounter, image recognition is performed with the alignment mark 209 on the substrate 200, the mounting position is adjusted, and then the silicon lens 204 is pressure-bonded. Then, heat treatment at about 200 degrees is performed and fixed. At this time, the second resin layer 252 under the silicon lens 204 is cured.

  Similarly, a silicon lens 205 that guides light incident from the optical fiber 212 to the light receiving element 206 is mounted. Similar to the silicon lens 204 on the light emitting element side, the silicon lens 205 is picked up, image recognition is performed with the alignment mark 209 and the mounting position is adjusted, and then the silicon lens 205 is pressure-bonded and heat treatment is performed at about 200 degrees. To fix. At this time, the second resin layer 252 under the silicon lens 205 is cured.

  Next, the light receiving element 206 is mounted. When the glass element 207 and the light receiving element 206 are bonded, first, the electrode pad formed on the glass surface and the light receiving element 206 are bonded by solder. At this time, alignment is performed using alignment marks on the front surface of the glass and the back surface of the light receiving element 206 as in the case of bonding between the light emitting element and the substrate. Mounting of the light receiving element 206 on the glass element 207 is performed separately from the flow of mounting on the substrate 200. Further, the glass element 207 on which the light receiving element 206 is mounted on the substrate 200 is mounted after the silicon lens 205 is mounted and before the wavelength filter 208 is mounted, similarly to the mounting of the light receiving element 206.

  Next, as shown in FIG. 18, the wavelength filter 208 is mounted. The mounting procedure is the same as that of the silicon lenses 204 and 205 and the light receiving element 206. That is, after the resin 252 is applied to the mounting position, image recognition is performed between the alignment mark 209 and the filter 208, the position is adjusted, and then crimped and heat-treated to be fixed. Through the steps as described above, the single-core bidirectional optical communication module of this embodiment is manufactured.

  According to the first embodiment of the present invention, the adhesive resin 252 does not flow into the optical path groove 202 even when the element is mounted, and the optical path of the received light inside the optical path groove 202 can be secured.

As mentioned above, although the Example of this invention was described, this invention is not limited to these Examples at all, It can change in the category of the technical idea shown by the claim.

FIG. 1 is a perspective view showing the structure of a conventional optical communication module. FIG. 2 is a side view showing a state observed from side A (reception side) and side B (transmission side) of FIG. FIG. 3 is a plan view showing an optical path of the conventional optical communication module shown in FIG. FIG. 4 is a side view showing the optical path of the conventional optical communication module shown in FIG. 1 separately for the reception side and the transmission side. FIG. 5 is a top view and a side view showing a part of the assembly process of the conventional optical communication module shown in FIG. 1, and shows a state before applying an adhesive resin. 6 is a top view and a side view showing a part of the assembly process of the conventional optical communication module shown in FIG. FIG. 7 is a top view and a side view showing a part of the assembly process of the conventional optical communication module shown in FIG. 1, and shows a state in which an element is mounted on an adhesive resin. FIG. 8 is an explanatory view (side view) for illustrating problems of the conventional optical communication module shown in FIG. FIG. 9 is an explanatory diagram (side view / reception side optical path) for illustrating the problems of the conventional optical communication module shown in FIG. FIG. 10 is a perspective view showing the structure of the optical communication module according to the embodiment of the present invention. FIG. 11 is a side view showing a state observed from the side surface A (reception side) and the side surface B (transmission side) in FIG. FIG. 12 is a plan view showing an optical path of the optical communication module according to the embodiment of the present invention. FIG. 13 is a side view showing the optical path of the optical communication module according to the embodiment of the present invention separately for the reception side and the transmission side. FIG. 14 is a top view and a side view showing a part of the manufacturing process of the optical communication module according to the embodiment of the present invention. FIG. 15 is a top view and a side view showing a part of the manufacturing process of the optical communication module according to the embodiment of the present invention. FIG. 16 is a top view and a side view showing a part of the manufacturing process of the optical communication module according to the embodiment of the present invention. FIG. 17 is a top view and a side view showing a part of the manufacturing process of the optical communication module according to the embodiment of the present invention. FIG. 18 is a top view and a side view showing a part of the manufacturing process of the optical communication module according to the embodiment of the present invention.

Explanation of symbols

200 Semiconductor substrate 201 Transmission side optical path groove (V groove)
202 Receiving side optical path groove (V groove)
203 Light Emitting Element (LD)
204 Transmission-side silicon lens 205 Reception-side silicon lens 206 Light-receiving element (PD)
208 Wavelength filter (demultiplexer)
209 Alignment mark 250 First resin layer 252 Second resin layer

Claims (12)

In an optical communication module comprising a plurality of optical elements mounted on a semiconductor substrate,
The semiconductor substrate is formed with an optical path groove through which at least one of transmission light or reception light passes,
At least one of the optical elements is bonded to the semiconductor substrate by an adhesive resin;
The adhesive resin comprises a hydrophobic first resin layer formed on the semiconductor substrate; and a second resin layer formed on the first resin layer. module.   The optical element includes: a light emitting element that outputs light for transmission (transmitted light); a light receiving element that converts received light (received light) into an electrical signal; received light guided to the light receiving element; and the light emitting element. The optical communication module according to claim 1, further comprising a wavelength filter that branches output light to be transmitted. The optical element further includes an output silicon lens that diffracts transmission light output from the light emitting element, and an input silicon lens that diffracts reception light incident on the light receiving element,
The input silicon lens is positioned with reference to the optical path groove,
The optical communication module according to claim 2, wherein at least a part of the bottom surface of the light receiving element is disposed on the optical path groove.   4. The optical communication module according to claim 3, wherein the optical path groove is provided with a reflecting member that guides the received light diffracted by the input silicon lens to the light receiving element.   5. The optical communication module according to claim 1, wherein the first resin layer is made of an acrylic resin containing a long-chain alkyl group.   5. The optical communication module according to claim 1, wherein the first resin layer is made of a polyimide resin not including an ether bond. A step of preparing a semiconductor substrate;
Forming an optical path groove through which light for reception or transmission passes on the surface of the semiconductor substrate;
Forming a hydrophobic first resin layer in a region on the semiconductor substrate on which an optical element is mounted;
Curing the first resin layer;
Forming a second resin layer on the first resin layer;
Mounting the optical element on the resin layer before curing the second resin layer;
And a step of curing the second resin layer after mounting the optical element.   The optical element includes: a light emitting element that outputs light for transmission (transmitted light); a light receiving element that converts received light (received light) into an electrical signal; received light guided to the light receiving element; and the light emitting element. The method of manufacturing an optical communication module according to claim 7, further comprising a wavelength filter that branches output light to be transmitted. The optical element further includes an output silicon lens that diffracts transmission light output from the light emitting element, and an input silicon lens that diffracts reception light incident on the light receiving element,
The input silicon lens is positioned with reference to the optical path groove,
9. The method of manufacturing an optical communication module according to claim 8, wherein at least a part of the bottom surface of the light receiving element is disposed on the optical path groove.   10. The method of manufacturing an optical communication module according to claim 9, wherein the optical path groove is provided with a reflecting member that guides the received light diffracted by the input silicon lens to the light receiving element.   The method of manufacturing an optical communication module according to claim 7, 8, 9, or 10, wherein the first resin layer is made of an acrylic resin containing a long-chain alkyl group.   11. The method of manufacturing an optical communication module according to claim 7, wherein the first resin layer is made of a polyimide resin not including an ether bond.

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