JP2005333018A - Optical component, optical communication device, electronic device, and manufacturing method for optical component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical component, an optical communication device, and an electronic device, which are capable of reducing light coupling loss and are highly reliable, and to provide a manufacturing method for the optical component. <P>SOLUTION: The optical component comprises an optical element 11 including a light emitter or a light receiver 13 having a projection 15 made of a transparent resin thereon, a translucent resin film 19 on which the optical element 11 is so placed as to bring the projection 15 into contact with the resin film 19, and a fixing means 17 which fixes the optical element 11 and the resin film 19 so that the projection 15 presses the resin film 19. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical component, an optical communication device, an electronic device, and an optical component manufacturing method that are preferably used in an optical communication system.

In recent years, development of optical communication systems has been progressing due to demands for higher speed and larger capacity of information communication.
Such an optical communication system basically has a configuration in which a light emitting element that converts an electrical signal into an optical signal and a light receiving element that converts an optical signal into an electrical signal are connected by an optical fiber. An optical communication module for optically connecting an optical element and an optical fiber is used in order to connect an optical fiber such as a light emitting element and a light receiving element to an optical fiber. For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2000-349307) discloses an optical communication module that can position an optical element and an optical fiber by using a through hole formed in a substrate (platform). . In this optical communication module, an example is described in which a resin having optical transparency is filled between an optical element fixed to a substrate and an optical fiber in order to relieve stress between the optical element and the substrate. Yes.
JP 2000-349307 A

However, when the light-transmitting resin is filled between the optical element and the substrate as in the above example, a fine gap due to bubbles or the like may occur at the time of filling, which may cause optical coupling loss.
On the other hand, when the optical element is placed on the substrate via the translucent resin film, if the optically transparent resin is filled between the optical element and the translucent resin film and cured, the optical transmission is performed. The side of the translucent resin film that contacts the optical fiber is recessed in a concave shape due to curing shrinkage of the translucent resin, and when the optical fiber is abutted against the translucent resin film, it is between the optical fiber and the translucent resin film. There is a possibility that voids are generated and optical coupling loss occurs.

  Accordingly, an object of the present invention is to provide an optical component, an optical communication device, an electronic apparatus, and a method for manufacturing an optical component that can reduce optical coupling loss and have high reliability.

  In order to solve the above problems, the present invention provides an optical element having a protrusion made of a transparent resin on a light emitting part or a light receiving part, and a translucent resin on which the optical element is placed so that the protrusion comes into contact with the optical element. An optical component comprising a film and fixing means for fixing the optical element and the translucent resin film so that the protruding portion presses the translucent resin film.

  According to such a configuration, the protrusion formed on the light emitting part or the light receiving part of the optical element is fixed so as to press the translucent resin film, and air is passed between the optical element and the translucent resin film. Since light can travel without intervention, light loss due to return light or the like can be reduced, and a highly reliable optical component can be provided. Further, when the underfill material is filled between the optical element and the translucent resin film, voids due to bubbles or the like are generated when the underfill material is filled, which may cause light loss. Also, when filling and curing the underfill material between the optical element and the translucent resin film, the side of the translucent resin film in contact with the optical fiber is recessed in a concave shape due to curing shrinkage of the translucent resin, When the optical fiber is abutted against the translucent resin film, a gap may be generated between the optical fiber and the translucent resin film, and optical coupling loss may occur. However, according to the present invention, such a problem does not occur because the previously formed protrusion is pressed against the translucent resin film. In addition, since the optical element is supported by the protrusions, the external stress can be further relaxed, and the impact resistance is improved. Furthermore, in general, there is a case where an underfill material containing a filler (hereinafter also referred to as a filler-containing underfill material) is desired to be relieved between the optical element and the mounting surface of the optical element in order to reduce thermal stress and the like. is there. However, when the filler-containing underfill material is disposed on the optical path, there is a risk of light loss due to light scattering by the filler. Moreover, in order to avoid the optical loss by a filler, it is difficult to arrange | position the underfill material containing a filler, and the underfill material which does not contain a filler. On the other hand, according to the present invention, the protruding portion of the optical element is fixed so as to press the translucent resin film, so that the end surface of the protruding portion and the translucent resin film are in close contact, and the filler-containing underfill material Even if it is used, the filler-containing underfill material does not enter the optical path between the light emitting section or the light receiving section and the light guide path such as an optical fiber, and the optical coupling loss can be reduced.

  It is preferable that a filler-containing underfill material is filled in a gap between the optical element and the translucent resin film. According to this, it becomes possible to relieve the stress with respect to the impact from the outside more. Moreover, it becomes possible to give an underfill material various characteristics by containing a filler in an underfill material. For example, by containing a filler, it is possible to adjust the thermal expansion coefficient and prevent interface peeling due to the difference in the thermal expansion coefficient between the optical element and the translucent resin film. Normally, an underfill material that does not contain a filler cannot adjust the thermal expansion coefficient, and therefore, when there is a difference in thermal expansion coefficient between the optical element and the optical element, the interface tends to peel off due to thermal shock. It is in.

  The immobilizing means fixes the optical element and the translucent resin film so that the protrusions press the translucent resin film to generate a refractive index distribution in the translucent resin film. Preferably it is a means.

  According to this, the translucent resin film can be made to act as a lens by pressing the translucent resin film with the protrusions to form a refractive index distribution. The collected light or the light entering the optical element can be collected. On the other hand, when a microlens is formed on a surface (light emitting surface or light receiving surface) on which a light emitting portion or a light receiving portion of an optical element is formed, and a lens effect is obtained by utilizing refraction on the surface of the microlens, It is necessary to maintain a predetermined distance from the translucent resin film so that the surface shape of the microlens is maintained. In contrast, in the present invention, since the refractive index distribution generated inside the translucent resin film is used, the distance between the optical element and the translucent resin film can be further narrowed, and the light guide path (optical fiber). It is possible to reduce the distance between and. Therefore, it is possible to further improve the optical coupling efficiency. Note that the refractive index distribution may be formed on both the protrusion and the translucent resin film.

The refractive index distribution preferably has a function as a convex lens. This makes it possible to collect light that passes through the translucent resin film.
The shape of the protruding portion is not particularly limited, but it is preferable that the light transmitting resin film can form a refractive index distribution having the same function as the convex lens. Specifically, the translucent resin film can be provided with a refractive index distribution such that the refractive index increases toward the center, and more specifically a hemispherical one.

  The immobilization means is a plurality of spacers arranged around the light emitting part or the light receiving part of the optical element, and the protrusion determines the limit value of the pressing force with which the translucent resin film is pressed. Preferably there is. According to this, it is possible to fix the protruding portion of the optical element in a state of being pressed against the translucent resin film, and it is possible to determine the limit value of the pressing force (pressing strength). The distribution can be controlled. Moreover, it becomes possible to prevent the translucent resin film from being damaged due to excessive pressing.

  The translucent resin film has a wiring film on at least one side, and the fixing means has a protruding shape protruding from the light emitting part or the light receiving part for electrical connection between the optical element and the wiring film. A connection terminal is preferable. According to this, since it is possible to serve both as a connection terminal for achieving electrical connection and a fixing means, the structure can be simplified.

  The translucent resin film has a hole portion formed so that the wiring film is exposed at a portion corresponding to a connection portion between the connection terminal and the wiring film, and the connection terminal includes the hole portion. It is preferable that it is connected to the wiring film via. According to this, since the light emitting surface or the light receiving surface of the optical element can be brought closer to the light guide path side, the optical coupling efficiency can be further improved.

  The light of the optical element is pressed so as to press the part corresponding to the part pressed by the projection of the optical element on the surface opposite to the side on which the optical element of the translucent resin film is mounted. An optical fiber fixed on the axis may be further included. By pressing the optical fiber against the translucent resin film, physical contact (PC) is possible, and light loss can be reduced. In addition, when the translucent resin film protrudes toward the optical fiber by being pressed by the protrusion of the optical element, the protrusion is further pushed back by the optical fiber, thereby generating a refractive index distribution, and as a convex lens. It is possible to have an action.

  The protrusion is preferably a microlens formed by a droplet discharge method. According to this, it becomes possible to easily control the lens shape. In addition, it is possible to form a convex refractive index distribution type lens having a higher refractive index toward the center.

Another aspect of the present invention is an optical communication device including the optical component. According to this, since the optical component is provided, it is possible to provide a highly reliable optical communication module with low optical coupling loss and good impact resistance.
Another aspect of the present invention is an electronic device including an optical component. According to this, since the optical component is provided, it is possible to provide a highly reliable optical communication module with low optical coupling loss and good impact resistance.

  Another aspect of the present invention includes a first step of forming a protrusion made of a transparent resin on the light emitting part or the light receiving part of the surface on which the light emitting part or the light receiving part of the optical element is formed, and the light emitting part Alternatively, a second step of forming a plurality of protruding connection terminals having a height of the main surface lower than the height of the protruding portion around the protruding portion of the surface on which the light receiving portion is formed, and a wiring film on at least one side And a third step of connecting the connection terminal to the wiring film such that a main surface of the connection terminal is in contact with the wiring film of the formed translucent resin film. Is.

  According to this, the height (gap setting height) of the main surface of the connection terminal is lower than the height of the protrusion. Therefore, when the optical element and the translucent resin film are joined, the pressing amount of the protrusion is adjusted by pressing the optical element until the main surface of the connection terminal is connected to the translucent resin film. It becomes possible to adjust the refractive index distribution generated by pressing the translucent resin film to a predetermined distribution. According to such a method, it is possible to manufacture an optical component having a small optical coupling loss and good impact resistance.

  Preferably, the protrusion is a microlens, and the first step is a step of forming a microlens by a droplet discharge method. According to this, it becomes possible to manufacture an optical component having a desired refractive index distribution by a simple method.

  Another aspect of the present invention includes a first step of forming a protrusion made of a transparent resin on the light emitting part or the light receiving part of the surface on which the light emitting part or the light receiving part of the optical element is formed, and the light emitting part Alternatively, the second step of forming a plurality of protruding connection terminals around the protrusion on the surface on which the light receiving portion is formed, and the connection terminal of the translucent resin film having a wiring film formed on at least one surface A third step of forming a hole in the translucent resin film so that the wiring film is exposed at a site to be installed, and a fourth step of connecting the connection terminal to the wiring film through the hole And a method for manufacturing an optical component. According to this, it becomes possible to easily manufacture an optical component in which the distance from the light emitting surface or the light receiving surface of the optical element to the light guide path is made closer.

  Preferably, the protrusion is a microlens, and the first step is a step of forming a microlens by a droplet discharge method. According to this, it becomes possible to manufacture an optical component having a desired refractive index distribution by a simple method.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a cross-sectional view for explaining an optical component according to this embodiment. 2A and 2B are diagrams for explaining the optical element used in the present embodiment. FIG. 2A is a perspective view and FIG. 2B is a top view.

  As shown in FIG. 1, the optical component 50 of the present embodiment is disposed around the optical element 11, the protrusion 15 made of a transparent resin provided on the light emitting part or the light receiving part 13 of the optical element 11, and the protrusion 15. The fixing means 17, the translucent resin film 19 on which the optical element 11 is placed, and the underfill material are mainly configured.

  The optical element 11 is mounted face-down on the translucent resin film 19 and placed on the translucent resin film 19 so that the light emitting part or the light receiving part 13 faces the translucent resin film 19. Therefore, light is exchanged between the optical element 11 and a light guide path (not shown in FIG. 1) such as an optical fiber through the translucent resin film 19. As the optical element 11, for example, a light emitting element such as a VCSEL (surface emitting laser) is used when the optical component 50 is used on the information transmitting side, and a light receiving element such as a PD is used when used on the information receiving side. Used. Hereinafter, in the present embodiment, a case where a VCSEL is used as the optical element 11 will be described as an example.

  As shown in FIGS. 2A and 2B, a protrusion 15 made of a transparent resin is formed on the light emitting portion 13 of the VCSEL 11, and an immobilization means 17 is provided around the protrusion 15. Is arranged.

  The protrusion 15 is for forming a refractive index distribution by pressing the translucent resin film 19 to generate an internal stress in the translucent resin film 19. Therefore, the shape of the protrusion 15 may be any shape that can form a refractive index distribution having a function as a convex lens in the translucent resin film 19. In the present embodiment, a hemispherical microlens is used as the protrusion 15. The protrusion 15 is made of a resin that can transmit laser light, such as an acrylic ultraviolet curable resin. The microlens as the protrusion 15 can be manufactured by, for example, dropping an ultraviolet curable resin or the like using a droplet discharge technique. The dripped resin becomes spherical due to surface tension, but the spherical state (radius, center position, etc.) changes depending on the dripping amount, so the lens shape can be adjusted by adjusting the dripping amount of the resin. is there.

  The immobilization unit 17 is configured to connect the VCSEL 11 and the light-transmitting resin film 19 to the VCSEL 11 and the light-transmitting resin film 19 so that the protrusion 15 formed on the VCSEL 11 presses the light-transmitting resin film 19 to generate a refractive index distribution. The resin film 19 is fixed. The fixing means 17 may also serve as a connection terminal for electrical connection between the wiring film 23 formed on the translucent resin film 19 described later and the VCSEL 11. The shape of the fixing means 17 (connection terminal) is not particularly limited as long as it has a protruding shape that protrudes from the surface on which the light emitting portion 13 of the VCSEL 11 is formed (hereinafter referred to as the light emitting surface 29). For example, a solder bump, a stud bump, or a wire bump is used. Further, the height of the main surface 18 of the fixing means 17 (the gap setting height for setting the interval between the VCSEL 11 and the translucent resin film 19) is set so that the protrusion 15 is fixed when the VCSEL 11 and the translucent resin film 19 are fixed. Is not particularly limited as long as it can press the translucent resin film 19.

  The immobilizing means 17 may serve as a spacer that determines the limit value of the pressing force with which the projection 15 presses the translucent resin film 19. When the translucent resin film 19 is a flat surface, from the viewpoint of determining the limit value of the pressing force, the height Y1 (gap setting height) of the main surface 18 of the fixing means 17 is set to be equal to that of the VCSEL 11. It is preferable that the height is lower than Y2. By adjusting the height Y1 of the main surface 18 of the fixing means 17, the limit value of the pressing force for pressing the translucent resin film 19 can be changed variously. It is possible to easily adjust the refractive index distribution formed in the desired distribution. In the case where the fixing means 17 also serves as a connection terminal, the constituent material of the fixing means 17 is not particularly limited as long as it has conductivity and can support the VCSEL 11. For example, Au ( Gold). The immobilization means 17 that functions as a connection terminal is formed, for example, above the anode electrode 33 and the cathode electrode 35.

  In the present embodiment, four fixing means 17 are formed in the vicinity (periphery) of each protrusion (microlens) 15. The number of fixing means 17 formed around each microlens 15 is not limited to four, and one or more desired numbers can be appropriately selected.

  The translucent resin film 19 is made of a resin that can transmit light, such as polyimide or epoxy resin. From the viewpoint of flexibility and easy handling, a polyimide film is preferably used. The translucent resin film 19 may include a wiring film 23 (first wiring film 23a or second wiring film 23b) formed on at least one side. The wiring film 23 is responsible for signal transmission with an electronic component such as a circuit chip (not shown), and is connected to the VCSEL 11 via a connection terminal (fixing means 17). The wiring film 23 is formed in a predetermined shape (wiring pattern) using a conductor such as copper. As such a translucent resin film 19, a flexible printed circuit board (FPC) may be used. Moreover, the wiring film 23 may be formed on both surfaces of the translucent resin film 19 as shown in FIG. In particular, in order to cope with the high-speed operation of the VCSEL 11, a microstrip line suitable for high-frequency signal transmission can be configured including the translucent resin film 19, the first wiring film 23a, and the second wiring film 23b. preferable. In FIG. 1, the first wiring film 23a formed on the upper surface side (VCSEL11 side) serves as a transmission line, and the second wiring film 23b formed on the lower surface side (opposite side where the VCSEL 11 is installed) is ground (reference). Potential).

  The underfill material 21 is filled between the VCSEL 11 and the translucent resin film 19 as necessary. When the underfill material 21 is filled, it is possible to relieve stress against an external impact. Further, by using an underfill material containing a filler, the underfill material can have various characteristics. For example, by including a filler such as silica and adjusting the coefficient of thermal expansion of the underfill material, it is possible to prevent interface peeling due to the difference in coefficient of thermal expansion between the optical element and the translucent resin film. In general, an underfill material that does not contain a filler has a large coefficient of thermal expansion, and therefore, when there is a difference in coefficient of thermal expansion between the optical element and the optical element, the interface tends to peel off due to thermal shock. .

  Next, the effect of the refractive index distribution formed on the translucent resin film 19 by the protrusion 15 will be described. FIG. 3 is a diagram for explaining the effect of the refractive index distribution formed on the translucent resin film 19. Here, FIG. 3A is a diagram showing a conventional optical component in which a refractive index distribution is not formed, and FIG. 3B is a diagram showing an optical component in which a refractive index distribution is formed.

  For example, a VCSEL that emits multimode oscillation with a radiation angle of about 35 degrees in all angles and has several modes depending on the radiation angle, and a high-speed GI type (Graded Index) with a core diameter of 50 μm A case where an optical fiber is used will be described as an example. Here, the NA of the GI type multimode optical fiber is about 0.21, and the angle of light that can be coupled is about 24 degrees. In addition, in the GI type multimode optical fiber, the angle of light that can be coupled is limited (smaller) as the distance from the center position increases, and becomes 0 at a radius of 25 μm at the end of the core. When the emitted light from the VCSEL is directly put into the GI type multimode optical fiber, as shown in FIG. 3A, when the refractive index distribution is not formed in the translucent resin film 19, the VCSEL 11 The light emitted from (a one-dot chain line in the figure) spreads in the direction of the emission angle of the VCSEL 11. Therefore, when the distance between the VCSEL and the GI type multimode optical fiber is wide, light with a larger angle is incident as the distance from the center of the GI type multimode optical fiber increases, and the light that can be coupled is reduced. become. For example, when it is assumed that the distance between the VCSEL 11 and the GI type multimode optical fiber is 110 μm and the space between the VCSEL 11 and the GI type multimode optical fiber is filled with a resin having a refractive index of 1.5 to 1.7, light having an emission angle of about 20 degrees or more is It will not be possible to couple to type multimode optical fiber. Therefore, if light of 20 degrees or more out of light having an emission angle of 35 degrees cannot be coupled, many VCSEL emission modes are not transmitted to the receiving side, and not only the signal loss is large, but also the signal waveform is distorted. . Further, since a coupling loss further occurs due to a shift in the center position between the VCSEL and the GI type multimode optical fiber, a high accuracy is required for the position accuracy.

  However, as shown in FIG. 3B, by forming a refractive index distribution having the function of a convex lens, it becomes possible to condense light emitted from the VCSEL 11 (dashed line in the figure). A signal with little coupling loss and small signal distortion can be transmitted. Therefore, it is possible to widen the margin for position adjustment.

  The refractive index distribution can be obtained by appropriately adjusting the shape of the protrusion 15, the selection of the material constituting the protrusion 15 and the translucent resin film 19, the height of the main surface 18 of the fixing means 17, and the like. Can be formed in a distribution.

  Next, the manufacturing method of the optical component 50 of this embodiment is demonstrated. FIG. 4 is a diagram for explaining a manufacturing process of the optical component 50. Hereinafter, in order to distinguish from the VCSEL wafer (base material) 100, the single VCSEL 11 is referred to as a VCSEL chip.

  First, as shown in FIG. 4A, a VCSEL wafer (mother base material) 100 to be a base material for each of a plurality of VCSEL chips is prepared. The VCSEL wafer 100 is a semiconductor substrate such as a GaAs substrate, for example, and a plurality of light emitting portions 13 are formed at predetermined intervals.

  Next, as shown in FIG. 4B, a microlens is formed as a protrusion 15 on one surface of the VCSEL wafer 100 and above each light emitting portion 13. Various methods can be adopted as a specific method for forming the microlens 15. In this embodiment, for example, each microlens 15 is formed by a droplet discharge method (so-called ink jet method).

  Specifically, as shown in FIG. 4B, a liquid material is dropped onto the VCSEL wafer 100 by the droplet discharge device 102, and the microlens 15 is formed by curing the dropped liquid material. As the liquid material to be dropped, for example, a photocurable resin material or a thermosetting resin material is preferably used. In this embodiment, an ultraviolet curable resin material is used. Since the dropped resin material is spheroidized by surface tension on the VCSEL wafer 100, the resin-made microlens 15 is obtained by irradiating the resin material with ultraviolet light and curing it. The microlens 15 having a desired shape (height, diameter, etc.) can be formed by appropriately selecting conditions such as the viscosity of the liquid resin material, the atmospheric temperature during formation, the surface shape of the VCSEL wafer 100 and the wettability. .

  Next, as shown in FIG. 4C, fixing means 17 whose main surface is lower than the top of each microlens 15 is formed at a plurality of locations on one surface of the VCSEL wafer 100. Here, the “uppermost portion” of the microlens 15 refers to the highest portion with respect to one surface (upper surface) of the VCSEL wafer 100, and in the illustrated example, the apex of the hemispherical microlens 15 corresponds to the substrate surface. . The fixing means 17 is formed so that the height of the main surface is lower than the apex of the microlens 15.

  Note that the order of forming the microlens 15 and the step of forming the fixing means 17 may be interchanged, or may be performed simultaneously.

  In the present embodiment, stud bumps are formed as the fixing means 17 by wire bonding. In this case, a pad made of Au (gold) or the like is provided in advance at a position where a stud bump on one surface of the VCSEL wafer 100 is to be formed. When a wire made of a conductive material such as Au is pressed against the pad and ultrasonic waves are applied, frictional heat is generated at the interface between the wire and the pad, and the tip of the wire is melted and welded to the pad. Thereafter, the stud bumps as shown in the figure are formed by tearing the wire.

  The arrangement state of the fixing means 17 is as shown in FIGS. 2 (A) and 2 (B). After the manufacturing process of the present embodiment is completed, the VCSEL chip 11 as illustrated is obtained. In addition, what is necessary is just to form the pad used at the time of formation of the stud bump mentioned above together with the formation of the anode electrode 33 and the cathode electrode 35 of VCSEL10, for example.

  Next, as shown in FIG. 4D, scribe lines 110 that divide the VCSEL wafer 100 into regions corresponding to the plurality of VCSEL chips 11 are formed. This process is performed using the dicing apparatus 106 provided with sharp blades, such as a diamond saw, for example. In this example, the protective sheet-like member 108 is used on the back surface (the other surface) of the VCSEL wafer 100 when the scribe line 110 is formed. As the sheet-like member 108, for example, a film made of a resin such as PET (polyethylene terephthalate) is used.

  Next, as shown in FIG. 4E, a crack 116 that separates the VCSEL wafer 100 into regions corresponding to the plurality of VCSEL chips 11 is formed. In this example, a blade 114 is struck from the back side (or front side) of the VCSEL wafer 100 to the position where the scribe line 110 of the VCSEL wafer 100 is formed, and each part of the VCSEL wafer 100 is cleaved along the crystal plane. By doing so, the crack 116 is formed.

  Next, as shown in FIG. 4F, the sheet-like member 108 is separated from the VCSEL wafer 100. Thereafter, by dividing the VCSEL wafer 100 along the above-described crack 116, a plurality of VCSEL chips 11 are obtained as shown in FIG.

  Next, as shown in FIGS. 5 (A) and 5 (B), the back surface of the VCSEL chip 11 is vacuum-adsorbed with the jig 120, and the translucent resin film 19 having the wiring film 23 formed on one side is applied to the translucent resin film 19. Flip chip bonding is performed by pressing the light emitting surface 29 downward. Specifically, the translucent resin film 19 (eg, polyimide film) is heated to about 250 ° C. and the VCSEL chip 11 is heated to about 380 ° C. to fix gold stud bumps or the like formed on the VCSEL chip 11. By pressing the means 17 against a metal pad such as a gold pad (not shown) provided on the translucent resin film 19, the gold are melted to form a metal bond. Here, when an acrylic ultraviolet curable resin, for example, is used as the material of the microlens 15, it is generally said that even a heat-resistant material cannot withstand a high temperature of 250 ° C. or higher. If so, for example, even if a temperature of 300 ° C. or higher is applied, there is often no problem. If the heat resistance of the resin constituting the microlens 15 is a problem, a bonding method using, for example, a solder ball other than the above-described metal bonding (gold-gold) (for example, a heating temperature of about 200 ° C.), or Other flip chip mounting methods such as a method in which a conductive adhesive is attached to the stud bumps and bonded with the conductive adhesive (for example, a heating temperature of about 150 ° C.) may be used.

  Here, in order to form a refractive index distribution in the translucent resin film 19, the microlens 15 is fixed to the translucent resin film 19 while being pressed. As a result, internal stress is generated in the microlens 15 and the translucent resin film 19, and a refractive index distribution is generated. Depending on the selection of the material constituting the microlens 15 and the translucent resin film 19, the refractive index distribution may be distributed more on the microlens 15 side, or more on the translucent resin film 19 side.

  In the present embodiment, stud bumps are used as the fixing means 17, and the stud bumps are pressed and joined so as to crush the tip portions. Therefore, in order for the microlens 15 to press the translucent resin film 19 when the VCSEL 11 and the translucent resin film 19 are bonded, the height of the microlens 15 is such that the height of the main surface 18 excluding the tip end portion of the stud bump. It is preferable to be higher than the height. This makes it possible to form the refractive index distribution more reliably. Further, since the translucent resin film 19 is pressed by the hemispherical microlens 15, internal stress is more strongly generated at the center portion, and the refractive index is increased. Therefore, the translucent resin film 19 in which the refractive index distribution is formed by the microlens 15 functions as a convex refractive index distribution type lens as a whole.

  Thereafter, as shown in FIG. 5C, the gap between the flip-chip bonded VCSEL 11 and the translucent resin film 19 is filled with an underfill material 21 whose thermal expansion coefficient is adjusted by a filler, and is cured and sealed. . When the thermal expansion coefficient of the underfill material 21 is set to an intermediate level between the thermal expansion coefficient of the VCSEL 11 and the thermal expansion coefficient of the translucent resin film 19, the peeling phenomenon due to thermal shock can be more effectively suppressed. As shown in FIG. 3A, when the underfill material 21 is filled without the projection (microlens) 15 interposed between the VCSEL 11 and the translucent resin film 19, the underfill material enters the light passage path. The material 21 will be filled. In this case, for example, when the underfill material 21 with a filler is used for the coefficient of thermal expansion, the light emitted from the VCSEL 11 by the filler may be absorbed and scattered, and the signal quality may deteriorate. However, according to the present embodiment, since the microlens 15 is interposed in the light passage path, the underfill material does not enter the passage path. Therefore, there is no risk of signal quality deterioration even when using an underfill material containing a filler, and since an underfill material with an adjusted coefficient of thermal expansion can be used, peeling due to thermal shock can be avoided. A highly reliable optical component 50 can be provided.

  According to the present embodiment, the translucent resin film 19 is pressed by the microlens as the projecting portion 15 to form a refractive index distribution, so that the translucent resin film 19 has a function as a lens. Therefore, the light emitted from the optical element (VCSEL) 11 can be collected. When a microlens is formed on the surface (light emitting surface 29) on which the light emitting portion of the optical element (VCSEL) 11 is formed and the lens effect is obtained by utilizing refraction on the surface of the microlens, the surface of the microlens It is necessary to maintain a predetermined distance from the translucent resin film so that the shape is maintained. In contrast, in the present embodiment, the microlens is used to form a refractive index distribution in the translucent resin film, and the effect as a lens is obtained from the refractive index distribution generated inside the translucent resin film. Therefore, the distance between the optical element and the translucent resin film can be further reduced. Therefore, the distance between the optical element (VCSEL) and the light guide path (optical fiber) can be reduced, and the optical coupling efficiency can be improved. In addition, since the optical element is supported by the protrusions and the fixing means, it is possible to relieve external stress and to improve the impact resistance.

  In the above example, the case where the optical component is applied to the transmission side has been described as an example. However, the present invention is not limited to this. Even when the present invention is applied to the receiving side, the light from the GI-type multimode optical fiber can be condensed into a smaller spot by the convex lens effect. For example, a PD (Photo Detector) used on the receiving side This is preferable because the adjustment margin can be increased. In addition, when the light spot is reduced, it is possible to use a high-speed PD having a small light receiving area, and thus it is possible to further increase the speed of optical communication.

  Further, for example, depending on the material of the material constituting the protrusion 15 and the translucent resin film 19, as shown in FIG. 6A, the translucent resin film 19 is formed by the protrusion 15 by the relaxation action of internal stress. The side opposite to the pressed side may bulge in a convex shape. However, also in this case, the portion deformed into the convex shape functions as a lens, and the same effect can be obtained. Further, as shown in FIG. 6B, the protruding portion of the translucent resin film 19 protruding in this way is corrected to a flat surface by pressing a light guide member 30 such as an optical fiber. Also good. Also in this case, the refractive index distribution is generated by pressing the convex portion, and the effect as a convex lens can be obtained.

(Second embodiment)
FIG. 7 is a diagram for explaining an optical component according to the second embodiment. 8A and 8B are diagrams for explaining the translucent resin film used in the second embodiment. FIG. 8A is a plan view and FIG. 8B is a cross-sectional view.

  As shown in FIG. 7, in the present embodiment, a hole 37 is provided at a position where the connection terminal 17 as a fixing means of the translucent resin film 19 is installed. The optical element 11 and the translucent resin film 19 are fixed by the connection terminal 17 through the hole 37. As shown in FIGS. 8A and 8B, the hole 37 is a wiring film formed on the lower surface of the translucent resin film 19 (the surface on the side opposite to where the optical element 11 is mounted). 23 is exposed. Thus, since the connection terminal 17 is connected to the wiring film 23 through the hole 37, the light emitting surface or the light receiving surface 29 of the optical element 11 and the optical element 11 of the translucent resin film 19 are opposite to each other. It becomes possible to further shorten the coupling distance with a light guide member such as an optical fiber (not shown) arranged on the side. In addition, since the connection terminal 17 enters the hole 37, the microlens as the projection 15 can press the translucent resin film 19 more reliably and form a refractive index distribution, which is preferable. .

FIG. 9 is a diagram for explaining a method of manufacturing an optical component according to the second embodiment. A case where a VCSEL is used as an optical element will be described as an example.
As in the first embodiment, the VCSEL chip 11 is formed.

  Next, as shown in FIG. 9A, the wiring film 23 is exposed at a portion to which the connection terminal 17 of the translucent resin film 19 in which the wiring film 23 such as Cu is patterned on one side is connected. A hole 37 is formed. Specifically, when the translucent resin film 19 is a polyimide film, the hole 37 is formed from the surface opposite to the side on which the wiring film 23 is formed, for example, by etching or laser.

  Next, as shown in FIG. 9B, the fixing means (stud bump) 17 is applied to the wiring film 23 exposed in the hole portion 37 through the hole portion 37 from the surface side where the hole portion 37 is formed. Flip chip bonding. At this time, a sufficient pressure is applied so that the protrusion 15 can press the translucent resin film 19.

  Next, as shown in FIG. 9C, the optical component 50 is obtained by filling the gap between the VCSEL chip 11 and the translucent resin film 19 with the filler-containing underfill material 21.

  According to the present embodiment, by providing the hole 37, it is possible to further narrow the distance between the light emitting surface 29 of the VCSEL 11 and a light guide member such as an optical fiber (not shown), and further reduce the coupling loss. Is possible. Further, since the gap between the light emitting surface 29 of the VCSEL 11 and the translucent resin film 19 is narrowed, it is possible to reliably press the translucent resin film 19 even when the protrusion (microlens) 15 is small. Even when a small microlens is used, the effect of a gradient index convex lens can be obtained.

(Optical communication device and electronic equipment)
The optical component 50 of the present invention is suitably used for an optical communication device. The optical communication device includes, for example, the optical component 50 of the present invention and a member such as a receptacle that holds a light guide member such as an optical fiber optically connected to the optical component 50.

  As an example of a member that holds the light guide member, for example, an optical fiber can be inserted into a base material made of a conductive material such as stainless steel, aluminum, or copper, or a non-conductive material such as glass, resin, or ceramic. Thus, a member having a hole capable of positioning the optical fiber and the optical element is mentioned.

  Moreover, the optical component or the optical communication apparatus of the present invention is suitably used for electronic devices such as personal computers, PDAs (portable information terminals), and electronic notebooks. Here, the electronic device means a general device that realizes a certain function using an electronic circuit or the like, and does not limit the configuration.

FIG. 1 is a cross-sectional view for explaining an optical component according to the first embodiment. FIG. 2 is a diagram for explaining an optical element used in the first embodiment. FIG. 3 is a diagram for explaining the effect of the refractive index distribution formed in the translucent resin film. FIG. 4 is a diagram for explaining a manufacturing process of the optical component according to the first embodiment. FIG. 5 is a diagram for explaining a manufacturing process of the optical component according to the first embodiment. FIG. 6 is a diagram for explaining a modification of the first embodiment. FIG. 7 is a diagram for explaining an optical component according to the second embodiment. FIG. 8 is a diagram for explaining a translucent resin film used in the second embodiment. FIG. 9 is a diagram for explaining a method of manufacturing an optical component according to the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Optical element, 13 ... Light emission part or light-receiving part, 15 ... Protrusion part (micro lens), 17 ... Fixing means (connection terminal), 18 ... Main surface, 19 ... Translucent resin film, 21: underfill material, 23 ... wiring film, 29 ... light emitting surface or light receiving surface, 30 ... light guide member, 33 ... anode electrode, 35 ... Cathode electrode, 37 ... hole, 50 ... optical component, 100 ... VCSEL wafer, 102 ... droplet discharge device, 104 ... light irradiation device, 106 ... dicing device, 108 ... Sheet-like member, 110 ... Scribe wire, 114 ... Blade, 116 ... Crack, 120 ... Jig

Claims (13)

An optical element having a protrusion made of a transparent resin on the light emitting part or the light receiving part;
A translucent resin film on which the optical element is placed so that the protrusion comes into contact;
Fixing means for fixing the optical element and the translucent resin film so that the protrusions press the translucent resin film;
An optical component comprising:   The optical component according to claim 1, wherein an underfill material containing a filler is filled in a gap between the optical element and the translucent resin film.   The immobilizing means fixes the optical element and the translucent resin film so that the protrusions press the translucent resin film to generate a refractive index distribution in the translucent resin film. The optical component according to claim 1, which is a means.   The optical component according to claim 3, wherein the refractive index distribution functions as a convex lens.   The fixing means is a plurality of spacers arranged around the light-emitting part or the light-receiving part of the optical element, and the protruding part determines a limit value of a pressing force for pressing the translucent resin film. Item 5. The optical component according to any one of Items 1 to 4. The translucent resin film comprises a wiring film on at least one side;
6. The fixing device according to claim 1, wherein the fixing means is a protruding connection terminal protruding from the light emitting unit or the light receiving unit for electrical connection between the optical element and the wiring film. Optical parts.   The translucent resin film has a hole portion formed so that the wiring film is exposed at a portion corresponding to a connection portion between the connection terminal and the wiring film, and the connection terminal includes the hole portion. The optical component according to claim 6, wherein the optical component is connected to the wiring film.   The light of the optical element is pressed so as to press the part corresponding to the part pressed by the projection of the optical element on the surface opposite to the side on which the optical element of the translucent resin film is mounted. The optical component according to claim 1, further comprising an optical fiber fixed on the axis.   The optical component according to claim 1, wherein the protrusion is a microlens formed by a droplet discharge method.   An optical communication apparatus comprising the optical component according to claim 1.   An electronic apparatus comprising the optical component according to claim 1. A first step of forming a protrusion made of a transparent resin on the light emitting part or the light receiving part of the surface on which the light emitting part or the light receiving part of the optical element is formed;
A second step of forming a plurality of protruding connection terminals having a height of a main surface lower than a height of the protruding portion around the protruding portion of the surface on which the light emitting portion or the light receiving portion is formed;
A third step of connecting the connection terminal to the wiring film such that the main surface of the connection terminal is in contact with the wiring film of the translucent resin film having the wiring film formed on at least one side;
The manufacturing method of the optical component characterized by including. A first step of forming a protrusion made of a transparent resin on the light emitting part or the light receiving part of the surface on which the light emitting part or the light receiving part of the optical element is formed;
A second step of forming a plurality of protruding connection terminals around the protruding portion of the surface on which the light emitting portion or the light receiving portion is formed;
A third step of forming a hole in the translucent resin film so that the wiring film is exposed at a portion where the connection terminal of the translucent resin film having the wiring film formed on at least one surface is installed;
A fourth step of connecting the connection terminal to the wiring film via the hole;
The manufacturing method of the optical component characterized by including.

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